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Main
Date: 15 Jun 2007 09:33:25
From:
Subject: What is a Solid State Emmiter?
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Does anyone know what a solid state emitter is? Is it an LED? Is it
like an LED?
http://www.vetta.com/Product_Lights_nMini.htm
Thanks,
alan.
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Date: 25 Jun 2007 06:06:09
From: bjw@mambo.ucolick.org
Subject: Re: What is a Solid State Emmiter?
|
On Jun 22, 7:08 pm, jim beam <spamvor...@bad.example.net > wrote:
> b...@mambo.ucolick.org wrote:
> > On Jun 20, 9:03 pm, jim beam <spamvor...@bad.example.net> wrote:
> >> Peter Cole wrote:
> >>> jim beam wrote:
> >>>> b...@mambo.ucolick.org wrote:
>
> >> what's the transition threshold between photons and phonons?
>
> > The way you've phrased this, your question does not make
> > any sense. Photons are light and phonons are mechanical
> > motions in a solid. The difference, for semiconductor
> > transitions, is that photons carry negligible momentum
> > and phonons have some momentum. So for an electron to
> > make a transition from one state to another state that
> > differs in momentum, it has to produce a phonon rather
> > than a photon. There's not a value of energy gap above
> > which transitions produce photons instead of phonons or
> > something like that.
>
> > Phonons aren't physical particles. They are a way of
> > representing the modes of vibration of a solid.
>
> thanks ben. this is indeed what i'm getting at. i've never seen
> momentum change described in any analysis of semiconductor electron
> energy theory. conduction, yes. excitation state transition, no.
> maybe i need to read more, but i'd welcome your enlightenment. peter
> seems to think i'm not asking a serious question.
One of my usual references for the quantum mechanics
of electrons in solids is Ashcroft and Mermin's "Solid
State Physics," but it's at my office. Anyway there
seem to be enough materials on the web.
The conduction band in a semiconductor gives the
energy range that electrons in some particular
set of quantum states are allowed to have. However,
electrons (unlike photons) have mass and so an
electron state with some energy may also have a significant
momentum. (Photons have momentum but it's insignificant
at these scales.)
The details of what momentum (p) an electron with
energy (E) has are pretty complex and depend on the
crystalline structure of the material.
http://people.deas.harvard.edu/~jones/ap216/lectures/ls_2/ls2_u7/sse_tut_1/solid1.html
Look at Figures 1.6.1 and 1.6.5 which give a schematic
idea of how the band gap arises in a crystal lattice.
These plot energy versus wavevector k; k is 1/wavelength
of the electron state (represented as a wave) and is here
equivalent to momentum, p = hbar*k. (hbar is Planck's
constant/2pi.)
In the plots on that page such as Figure 1.6.6, the band
structure is such that the energy is symmetric about k=0,
so an electron in some band will settle to the lowest
energy in that band at k=0 and have zero momentum.
However, in real semiconductors this is often not true
and the conduction band energy minimum is at non-zero
momentum. See the figure at
http://en.wikipedia.org/wiki/Indirect_bandgap
and panels (b) and (c) of Figure 4.6.1 at
http://ece-www.colorado.edu/~bart/book/book/chapter4/ch4_6.htm#fig4_6_1
(I gave this link earlier in the thread.)
Momentum is conserved. As section 4.6.1 of that page
discusses, in an indirect band gap material, in order
for an electron to drop from the conduction band to the
valence band it has to lose both energy and momentum.
Photons don't have enough momentum so the reaction
has to produce a phonon (a sound wave oscillation of the
crystal). The phonon can also carry off energy. In order
for any energy to go into light, a two-step process
has to occur involving electron, phonon, and photon.
Although these can occur, they are much less likely,
and so the vast majority of the time an electron will
drop out of the conduction band without producing light.
To make an LED or photodiode, visible or infrared, one
has to overcome this by using a semiconductor material
that has a direct band gap. And if that seems like
a pain in the butt, imagine designing electronic detectors
that work in the thermal infrared!
Ben
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Date: 25 Jun 2007 06:18:14
From: jim beam
Subject: Re: What is a Solid State Emmiter?
|
bjw@mambo.ucolick.org wrote:
> On Jun 22, 7:08 pm, jim beam <spamvor...@bad.example.net> wrote:
>> b...@mambo.ucolick.org wrote:
>>> On Jun 20, 9:03 pm, jim beam <spamvor...@bad.example.net> wrote:
>>>> Peter Cole wrote:
>>>>> jim beam wrote:
>>>>>> b...@mambo.ucolick.org wrote:
>>>> what's the transition threshold between photons and phonons?
>>> The way you've phrased this, your question does not make
>>> any sense. Photons are light and phonons are mechanical
>>> motions in a solid. The difference, for semiconductor
>>> transitions, is that photons carry negligible momentum
>>> and phonons have some momentum. So for an electron to
>>> make a transition from one state to another state that
>>> differs in momentum, it has to produce a phonon rather
>>> than a photon. There's not a value of energy gap above
>>> which transitions produce photons instead of phonons or
>>> something like that.
>>> Phonons aren't physical particles. They are a way of
>>> representing the modes of vibration of a solid.
>> thanks ben. this is indeed what i'm getting at. i've never seen
>> momentum change described in any analysis of semiconductor electron
>> energy theory. conduction, yes. excitation state transition, no.
>> maybe i need to read more, but i'd welcome your enlightenment. peter
>> seems to think i'm not asking a serious question.
>
> One of my usual references for the quantum mechanics
> of electrons in solids is Ashcroft and Mermin's "Solid
> State Physics," but it's at my office. Anyway there
> seem to be enough materials on the web.
>
> The conduction band in a semiconductor gives the
> energy range that electrons in some particular
> set of quantum states are allowed to have. However,
> electrons (unlike photons) have mass and so an
> electron state with some energy may also have a significant
> momentum. (Photons have momentum but it's insignificant
> at these scales.)
> The details of what momentum (p) an electron with
> energy (E) has are pretty complex and depend on the
> crystalline structure of the material.
>
> http://people.deas.harvard.edu/~jones/ap216/lectures/ls_2/ls2_u7/sse_tut_1/solid1.html
>
> Look at Figures 1.6.1 and 1.6.5 which give a schematic
> idea of how the band gap arises in a crystal lattice.
> These plot energy versus wavevector k; k is 1/wavelength
> of the electron state (represented as a wave) and is here
> equivalent to momentum, p = hbar*k. (hbar is Planck's
> constant/2pi.)
>
> In the plots on that page such as Figure 1.6.6, the band
> structure is such that the energy is symmetric about k=0,
> so an electron in some band will settle to the lowest
> energy in that band at k=0 and have zero momentum.
> However, in real semiconductors this is often not true
> and the conduction band energy minimum is at non-zero
> momentum. See the figure at
>
> http://en.wikipedia.org/wiki/Indirect_bandgap
>
> and panels (b) and (c) of Figure 4.6.1 at
>
> http://ece-www.colorado.edu/~bart/book/book/chapter4/ch4_6.htm#fig4_6_1
> (I gave this link earlier in the thread.)
>
> Momentum is conserved. As section 4.6.1 of that page
> discusses, in an indirect band gap material, in order
> for an electron to drop from the conduction band to the
> valence band it has to lose both energy and momentum.
> Photons don't have enough momentum so the reaction
> has to produce a phonon (a sound wave oscillation of the
> crystal). The phonon can also carry off energy. In order
> for any energy to go into light, a two-step process
> has to occur involving electron, phonon, and photon.
> Although these can occur, they are much less likely,
> and so the vast majority of the time an electron will
> drop out of the conduction band without producing light.
>
> To make an LED or photodiode, visible or infrared, one
> has to overcome this by using a semiconductor material
> that has a direct band gap. And if that seems like
> a pain in the butt, imagine designing electronic detectors
> that work in the thermal infrared!
>
> Ben
>
>
>
interesting stuff. thanks ben - i'll be reading more on that!
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Date: 25 Jun 2007 11:46:21
From: Peter Cole
Subject: Re: What is a Solid State Emmiter?
|
jim beam wrote:
> bjw@mambo.ucolick.org wrote:
>> To make an LED or photodiode, visible or infrared, one
>> has to overcome this by using a semiconductor material
>> that has a direct band gap. And if that seems like
>> a pain in the butt, imagine designing electronic detectors
>> that work in the thermal infrared!
>>
>> Ben
>>
>>
>>
> interesting stuff. thanks ben - i'll be reading more on that!
When you do, you may wish to revisit:
"all semiconductors emit electromagnetic radiation as excited electrons
drop to a less excited state"
Do get back to us.
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Date: 25 Jun 2007 22:25:29
From: jim beam
Subject: Re: What is a Solid State Emmiter?
|
Peter Cole wrote:
> jim beam wrote:
>> bjw@mambo.ucolick.org wrote:
>
>>> To make an LED or photodiode, visible or infrared, one
>>> has to overcome this by using a semiconductor material
>>> that has a direct band gap. And if that seems like
>>> a pain in the butt, imagine designing electronic detectors
>>> that work in the thermal infrared!
>>>
>>> Ben
>>>
>>>
>>>
>> interesting stuff. thanks ben - i'll be reading more on that!
>
> When you do, you may wish to revisit:
> "all semiconductors emit electromagnetic radiation as excited electrons
> drop to a less excited state"
>
> Do get back to us.
when i decypher the educational content of "Same as apples to oranges.",
i might.
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Date: 22 Jun 2007 16:16:10
From: bjw@mambo.ucolick.org
Subject: Re: What is a Solid State Emmiter?
|
On Jun 20, 9:03 pm, jim beam <spamvor...@bad.example.net > wrote:
> Peter Cole wrote:
> > jim beam wrote:
> >> b...@mambo.ucolick.org wrote:
>
> >>> When you say "that emission," what are you referring to
> >>> by "that"?
>
> >> the emission associated with an electron dropping from one band to
> >> another at a lower level. unless physics have changed any since i
> >> last did this stuff, that emission is a photon.
>
> > Or a phonon, hence non-radiative (non-optical) recombination, the
> > typical mode of indirect bandgap materials like silicon & germanium.
>
> what's the transition threshold between photons and phonons?
The way you've phrased this, your question does not make
any sense. Photons are light and phonons are mechanical
motions in a solid. The difference, for semiconductor
transitions, is that photons carry negligible momentum
and phonons have some momentum. So for an electron to
make a transition from one state to another state that
differs in momentum, it has to produce a phonon rather
than a photon. There's not a value of energy gap above
which transitions produce photons instead of phonons or
something like that.
Phonons aren't physical particles. They are a way of
representing the modes of vibration of a solid.
Ben
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Date: 22 Jun 2007 19:08:22
From: jim beam
Subject: Re: What is a Solid State Emmiter?
|
bjw@mambo.ucolick.org wrote:
> On Jun 20, 9:03 pm, jim beam <spamvor...@bad.example.net> wrote:
>> Peter Cole wrote:
>>> jim beam wrote:
>>>> b...@mambo.ucolick.org wrote:
>>>>> When you say "that emission," what are you referring to
>>>>> by "that"?
>>>> the emission associated with an electron dropping from one band to
>>>> another at a lower level. unless physics have changed any since i
>>>> last did this stuff, that emission is a photon.
>>> Or a phonon, hence non-radiative (non-optical) recombination, the
>>> typical mode of indirect bandgap materials like silicon & germanium.
>> what's the transition threshold between photons and phonons?
>
>
> The way you've phrased this, your question does not make
> any sense. Photons are light and phonons are mechanical
> motions in a solid. The difference, for semiconductor
> transitions, is that photons carry negligible momentum
> and phonons have some momentum. So for an electron to
> make a transition from one state to another state that
> differs in momentum, it has to produce a phonon rather
> than a photon. There's not a value of energy gap above
> which transitions produce photons instead of phonons or
> something like that.
>
> Phonons aren't physical particles. They are a way of
> representing the modes of vibration of a solid.
>
thanks ben. this is indeed what i'm getting at. i've never seen
momentum change described in any analysis of semiconductor electron
energy theory. conduction, yes. excitation state transition, no.
maybe i need to read more, but i'd welcome your enlightenment. peter
seems to think i'm not asking a serious question.
|
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Date: 23 Jun 2007 13:27:09
From: Peter Cole
Subject: Re: What is a Solid State Emmiter?
|
jim beam wrote:
> bjw@mambo.ucolick.org wrote:
>> On Jun 20, 9:03 pm, jim beam <spamvor...@bad.example.net> wrote:
>>> what's the transition threshold between photons and phonons?
>>
>>
>> The way you've phrased this, your question does not make
>> any sense. Photons are light and phonons are mechanical
>> motions in a solid.
>>
> thanks ben. this is indeed what i'm getting at. i've never seen
> momentum change described in any analysis of semiconductor electron
> energy theory.
> peter seems to think i'm not asking a serious question.
No, just an unanswerable one (nonsensical, as Ben says).
Perhaps this will help:
http://britneyspears.ac/physics/indirect/indirect.htm
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Date: 24 Jun 2007 06:54:36
From: Michael Press
Subject: Re: What is a Solid State Emmiter?
|
In article
<tZedneIzV55wyuDbnZ2dnUVZ_tfinZ2d@comcast.com >,
Peter Cole <peter_cole@comcast.net > wrote:
> jim beam wrote:
> > bjw@mambo.ucolick.org wrote:
> >> On Jun 20, 9:03 pm, jim beam <spamvor...@bad.example.net> wrote:
>
> >>> what's the transition threshold between photons and phonons?
> >>
> >>
> >> The way you've phrased this, your question does not make
> >> any sense. Photons are light and phonons are mechanical
> >> motions in a solid.
> >>
> > thanks ben. this is indeed what i'm getting at. i've never seen
> > momentum change described in any analysis of semiconductor electron
> > energy theory.
>
> > peter seems to think i'm not asking a serious question.
>
> No, just an unanswerable one (nonsensical, as Ben says).
>
> Perhaps this will help:
>
> http://britneyspears.ac/physics/indirect/indirect.htm
We have strayed quite a bit from bicycles.
<URL:http://britneyspears.ac/hepcj/images/g3/bsac031.jpg >
--
Michael Press
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Date: 23 Jun 2007 14:01:12
From: Bill Sornson
Subject: Re: What is a Solid State Emmiter?
|
Peter Cole wrote:
> jim beam wrote:
>> bjw@mambo.ucolick.org wrote:
>>> On Jun 20, 9:03 pm, jim beam <spamvor...@bad.example.net> wrote:
>
>>>> what's the transition threshold between photons and phonons?
>>>
>>>
>>> The way you've phrased this, your question does not make
>>> any sense. Photons are light and phonons are mechanical
>>> motions in a solid.
>>>
>> thanks ben. this is indeed what i'm getting at. i've never seen
>> momentum change described in any analysis of semiconductor electron
>> energy theory.
>
>> peter seems to think i'm not asking a serious question.
>
> No, just an unanswerable one (nonsensical, as Ben says).
>
> Perhaps this will help:
>
> http://britneyspears.ac/physics/indirect/indirect.htm
Omega headphones?
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Date: 20 Jun 2007 11:17:54
From: Kendall Willets
Subject: Re: What is a Solid State Emmiter?
|
On Jun 15, 9:33 am, aburde...@gmail.com wrote:
> Does anyone know what a solid state emitter is? Is it an LED? Is it
> like an LED?
>
> http://www.vetta.com/Product_Lights_nMini.htm
>
> Thanks,
>
> alan.
It's normally an led packaged with optic output, electrical
connections, and heat sinking, in some sort of surface-mount design.
But if it's $80.00, it's a ripoff.
Currently the best, Cree emitters run about $7-12 in single
quantities. Places like kaidomain.com and dealextreme.com will sell
you an entire 3W Cree-based flashlight with Li-ion battery and charger
for $30 or less, and they publish credible runtime graphs.
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Date: 20 Jun 2007 17:34:32
From: Bill
Subject: Re: What is a Solid State Emmiter?
|
Kendall Willets wrote:
> On Jun 15, 9:33 am, aburde...@gmail.com wrote:
>> Does anyone know what a solid state emitter is? Is it an LED? Is it
>> like an LED?
>>
>> http://www.vetta.com/Product_Lights_nMini.htm
>>
>> Thanks,
>>
>> alan.
>
> It's normally an led packaged with optic output, electrical
> connections, and heat sinking, in some sort of surface-mount design.
> But if it's $80.00, it's a ripoff.
>
> Currently the best, Cree emitters run about $7-12 in single
> quantities. Places like kaidomain.com and dealextreme.com will sell
> you an entire 3W Cree-based flashlight with Li-ion battery and charger
> for $30 or less, and they publish credible runtime graphs.
>
I'm using a Cat-Eye with 5 LEDs in parallel, so if one burns out the
other 4 will be just a bit brighter. It uses 4 AA rechargeable NiMH
batteries and will stay bright all night on one charge. Since the
rechargeables run 1.2 volts and alkalines run 1.5 volts you will get
more light from the alkalines, at first, but when you notice the light
dropping off it is time to buy some more. Since the Cat-Eye is
dismountable I use it as a flash light too, and it beats my
incandescent. The double duty is nice since I sometimes get off the bike
at night and try to sneak up on frogs and other night life in the
country. Do try to avoid proprietary Lithium batteries since the cost of
replacing them is often more than a whole new light.
Bill Baka
Note: The Cat-Eye only uses resistors and no fancy electronics.
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Date: 19 Jun 2007 05:18:52
From: bjw@mambo.ucolick.org
Subject: Re: What is a Solid State Emmiter?
|
On Jun 18, 7:39 pm, jim beam <spamvor...@bad.example.net > wrote:
> b...@mambo.ucolick.org wrote:
> > What are you talking about? The difference Peter
> > mentioned (direct/indirect gap materials) is completely
> > consistent with everything we know about Fermi
> > statistics. In indirect gap materials, photon
> > absorption or emission is accompanied by a phonon
> > (That's a sound wave in the material, for those
> > of you not used to the jargon.) Because it is a
> > two-step process, the energy of the photon will not
> > be precise. Also the light absorption and emission
> > is much less efficient. This is why LEDs and
> > photodiodes are made out of special materials,
> > not J. Random Semiconductor.
>
> > See Figure 4.6.1 in
> >http://ece-www.colorado.edu/~bart/book/book/chapter4/ch4_6.htm#4_6_1
>
> > It's true that all semiconductors also give off
> > heat in operation, which means they are emitting
> > thermal infrared radiation, but this is not the
> > same process as the one that makes LEDs and laser
> > diodes work. (LEDs and laser diodes emit both
> > visible or near-IR radiation in a relatively narrow
> > wavelength range, and the usual heat radiation.)
>
> but that emission is a function of the band gap! the narrower the gap,
> the longer the wavelength. "normal" semicons just have a longer wavelength.
When you say "that emission," what are you referring to
by "that"? The emission from photon transitions at the
energy of the band gap, or the thermal infrared
radiation? They are two quite different things.
"Normal" semiconductors don't just have a longer wavelength =
smaller band gap than LEDs. After all, LEDs come in a variety
of wavelengths from optical to near-infrared (say 1-2 micron
wavelength). Normal semiconductors just are miserably
inefficient emitters in the optical or near-IR because
of the indirect band gap business explained in the
Figure 4.6.1 that I referenced above.
> back in the days of glass-encased germanium semicons, you could scrape
> off the black paint and use them as emitters & receivers.
I don't doubt this. If you build detectors for very very
sensitive dark applications, you have to worry about
light leaks from electronics packaging, since typical
packages are often not opaque in the near-IR. However,
leaky optoisolators are a much more common problem than
leaky ordinary semiconductors, because ordinary semicons
emit a trivial amount of optical/near-IR light. That's
the red herring you claimed originally, for whatever
reason.
Ben
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Date: 19 Jun 2007 21:05:53
From: jim beam
Subject: Re: What is a Solid State Emmiter?
|
bjw@mambo.ucolick.org wrote:
> On Jun 18, 7:39 pm, jim beam <spamvor...@bad.example.net> wrote:
>> b...@mambo.ucolick.org wrote:
>
>>> What are you talking about? The difference Peter
>>> mentioned (direct/indirect gap materials) is completely
>>> consistent with everything we know about Fermi
>>> statistics. In indirect gap materials, photon
>>> absorption or emission is accompanied by a phonon
>>> (That's a sound wave in the material, for those
>>> of you not used to the jargon.) Because it is a
>>> two-step process, the energy of the photon will not
>>> be precise. Also the light absorption and emission
>>> is much less efficient. This is why LEDs and
>>> photodiodes are made out of special materials,
>>> not J. Random Semiconductor.
>>> See Figure 4.6.1 in
>>> http://ece-www.colorado.edu/~bart/book/book/chapter4/ch4_6.htm#4_6_1
>>> It's true that all semiconductors also give off
>>> heat in operation, which means they are emitting
>>> thermal infrared radiation, but this is not the
>>> same process as the one that makes LEDs and laser
>>> diodes work. (LEDs and laser diodes emit both
>>> visible or near-IR radiation in a relatively narrow
>>> wavelength range, and the usual heat radiation.)
>> but that emission is a function of the band gap! the narrower the gap,
>> the longer the wavelength. "normal" semicons just have a longer wavelength.
>
> When you say "that emission," what are you referring to
> by "that"?
the emission associated with an electron dropping from one band to
another at a lower level. unless physics have changed any since i last
did this stuff, that emission is a photon. whether or not it's of a
wavelength to be visible to humans is another matter.
> The emission from photon transitions at the
> energy of the band gap, or the thermal infrared
> radiation? They are two quite different things.
indeed.
>
> "Normal" semiconductors don't just have a longer wavelength =
> smaller band gap than LEDs.
that's true - i was addressing those who were stuck on optical.
> After all, LEDs come in a variety
> of wavelengths from optical to near-infrared (say 1-2 micron
> wavelength). Normal semiconductors just are miserably
> inefficient emitters in the optical or near-IR because
> of the indirect band gap business explained in the
> Figure 4.6.1 that I referenced above.
they may indeed be dismal, but it doesn't mean they don't emit.
>
>> back in the days of glass-encased germanium semicons, you could scrape
>> off the black paint and use them as emitters & receivers.
>
> I don't doubt this. If you build detectors for very very
> sensitive dark applications, you have to worry about
> light leaks from electronics packaging, since typical
> packages are often not opaque in the near-IR. However,
> leaky optoisolators are a much more common problem than
> leaky ordinary semiconductors, because ordinary semicons
> emit a trivial amount of optical/near-IR light. That's
> the red herring you claimed originally, for whatever
> reason.
i wasn't talking about optoisolators, so /that/ is a herring.
|
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Date: 20 Jun 2007 08:14:01
From: Peter Cole
Subject: Re: What is a Solid State Emmiter?
|
jim beam wrote:
> bjw@mambo.ucolick.org wrote:
>> When you say "that emission," what are you referring to
>> by "that"?
>
> the emission associated with an electron dropping from one band to
> another at a lower level. unless physics have changed any since i last
> did this stuff, that emission is a photon.
Or a phonon, hence non-radiative (non-optical) recombination, the
typical mode of indirect bandgap materials like silicon & germanium.
|
| | | | |
Date: 20 Jun 2007 21:03:23
From: jim beam
Subject: Re: What is a Solid State Emmiter?
|
Peter Cole wrote:
> jim beam wrote:
>> bjw@mambo.ucolick.org wrote:
>
>>> When you say "that emission," what are you referring to
>>> by "that"?
>>
>> the emission associated with an electron dropping from one band to
>> another at a lower level. unless physics have changed any since i
>> last did this stuff, that emission is a photon.
>
> Or a phonon, hence non-radiative (non-optical) recombination, the
> typical mode of indirect bandgap materials like silicon & germanium.
what's the transition threshold between photons and phonons?
|
| | | | | |
Date: 22 Jun 2007 10:25:36
From: Peter Cole
Subject: Re: What is a Solid State Emmiter?
|
jim beam wrote:
> Peter Cole wrote:
>> jim beam wrote:
>>> bjw@mambo.ucolick.org wrote:
>>
>>>> When you say "that emission," what are you referring to
>>>> by "that"?
>>>
>>> the emission associated with an electron dropping from one band to
>>> another at a lower level. unless physics have changed any since i
>>> last did this stuff, that emission is a photon.
>>
>> Or a phonon, hence non-radiative (non-optical) recombination, the
>> typical mode of indirect bandgap materials like silicon & germanium.
>
> what's the transition threshold between photons and phonons?
Same as apples to oranges.
|
| | | | |
Date: 20 Jun 2007 16:28:02
From: still me
Subject: Re: What is a Solid State Emmiter?
|
On Wed, 20 Jun 2007 08:14:01 -0400, Peter Cole
<peter_cole@comcast.net > wrote:
>> the emission associated with an electron dropping from one band to
>> another at a lower level. unless physics have changed any since i last
>> did this stuff, that emission is a photon.
>
>Or a phonon, hence non-radiative (non-optical) recombination, the
>typical mode of indirect bandgap materials like silicon & germanium.
I thought "photon"s were those small pictures you see when you load
the pictures from your digital camera onto your PC before you pull in
the full images.
|
| |
Date: 18 Jun 2007 15:57:33
From: bjw@mambo.ucolick.org
Subject: Re: What is a Solid State Emmiter?
|
On Jun 18, 6:16 am, jim beam <spamvor...@bad.example.net > wrote:
> Peter Cole wrote:
> > jim beam wrote:
> >> Peter Cole wrote:
>
> >>> If you consider silicon and germanium to be "normal", then no, they
> >>> don't emit light typically during the process of recombination (e.g.
> >>> current flow through a p-n junction, the process which causes LED's
> >>> to emit photons (on a variety of wavelengths).
>
> >> they emit infrared!!! and the wavelength is very precise as a
> >> function of energy gap.
>
> > No, they do not. You are mistaken. Indirect bandgap materials require a
> > change in both electron energy and momentum to move from valence to
> > conduction band. Photon emission doesn't provide the necessary change in
> > momentum.
>
> so why didn't fermi pick up on that then? all my laser science would be
> up s-creek without him.
What are you talking about? The difference Peter
mentioned (direct/indirect gap materials) is completely
consistent with everything we know about Fermi
statistics. In indirect gap materials, photon
absorption or emission is accompanied by a phonon
(That's a sound wave in the material, for those
of you not used to the jargon.) Because it is a
two-step process, the energy of the photon will not
be precise. Also the light absorption and emission
is much less efficient. This is why LEDs and
photodiodes are made out of special materials,
not J. Random Semiconductor.
See Figure 4.6.1 in
http://ece-www.colorado.edu/~bart/book/book/chapter4/ch4_6.htm#4_6_1
It's true that all semiconductors also give off
heat in operation, which means they are emitting
thermal infrared radiation, but this is not the
same process as the one that makes LEDs and laser
diodes work. (LEDs and laser diodes emit both
visible or near-IR radiation in a relatively narrow
wavelength range, and the usual heat radiation.)
Ben
|
| | |
Date: 18 Jun 2007 19:39:13
From: jim beam
Subject: Re: What is a Solid State Emmiter?
|
bjw@mambo.ucolick.org wrote:
> On Jun 18, 6:16 am, jim beam <spamvor...@bad.example.net> wrote:
>> Peter Cole wrote:
>>> jim beam wrote:
>>>> Peter Cole wrote:
>>>>> If you consider silicon and germanium to be "normal", then no, they
>>>>> don't emit light typically during the process of recombination (e.g.
>>>>> current flow through a p-n junction, the process which causes LED's
>>>>> to emit photons (on a variety of wavelengths).
>>>> they emit infrared!!! and the wavelength is very precise as a
>>>> function of energy gap.
>>> No, they do not. You are mistaken. Indirect bandgap materials require a
>>> change in both electron energy and momentum to move from valence to
>>> conduction band. Photon emission doesn't provide the necessary change in
>>> momentum.
>> so why didn't fermi pick up on that then? all my laser science would be
>> up s-creek without him.
>
> What are you talking about? The difference Peter
> mentioned (direct/indirect gap materials) is completely
> consistent with everything we know about Fermi
> statistics. In indirect gap materials, photon
> absorption or emission is accompanied by a phonon
> (That's a sound wave in the material, for those
> of you not used to the jargon.) Because it is a
> two-step process, the energy of the photon will not
> be precise. Also the light absorption and emission
> is much less efficient. This is why LEDs and
> photodiodes are made out of special materials,
> not J. Random Semiconductor.
>
> See Figure 4.6.1 in
> http://ece-www.colorado.edu/~bart/book/book/chapter4/ch4_6.htm#4_6_1
>
> It's true that all semiconductors also give off
> heat in operation, which means they are emitting
> thermal infrared radiation, but this is not the
> same process as the one that makes LEDs and laser
> diodes work. (LEDs and laser diodes emit both
> visible or near-IR radiation in a relatively narrow
> wavelength range, and the usual heat radiation.)
>
but that emission is a function of the band gap! the narrower the gap,
the longer the wavelength. "normal" semicons just have a longer wavelength.
back in the days of glass-encased germanium semicons, you could scrape
off the black paint and use them as emitters & receivers.
|
| | | |
Date: 19 Jun 2007 02:59:23
From: Bill
Subject: Re: What is a Solid State Emmiter?
|
jim beam wrote:
>
> back in the days of glass-encased germanium semicons, you could scrape
> off the black paint and use them as emitters & receivers.
Heh.
I have some in a drawer or box somewhere with clear tops. Like a 1955
photo-transistor. I have 2N107 and 2N170 pairs, along with some CK722's
and a lot of old weird stuff that I either saved for 50+ years or found
on Ebay.
Lots of 1N34 diodes, too.
I still preferred cat whiskers on Gillette blue blades oxide coating.
Bill (showing my age) Baka
|
| |
Date: 18 Jun 2007 08:26:46
From: bjw@mambo.ucolick.org
Subject: Re: What is a Solid State Emmiter?
|
On Jun 15, 9:46 am, Victor Kan <victor....@gmail.com > wrote:
> On Jun 15, 12:33 pm, aburde...@gmail.com wrote:
>
> > Does anyone know what a solid state emitter is? Is it an LED? Is it
> > like an LED?
>
> >http://www.vetta.com/Product_Lights_nMini.htm
>
> Yep, it's an LED.
>
> Maybe the term "solid state emitter" harkens back to the days when
> transistor based electronics came on the market and where brands
> wanted you to know your TV or whatever was "solid state" and turned on
> right away rather than having to warm up.
>
> Maybe with bike lights, they're playing up the solid state for
> durability against vibration and impacts, as well as not having to
> "warm up" (as HID lights do).
LEDs are solid state light sources, as opposed to glass
bulbs that are either evacuated or filled with some
exotic gas, and driven by filaments or discharges.
In that respect, they are quite analogous to the
difference between "solid state" and vacuum-tube TVs,
although of course even solid-state TVs used an
evacuated CRT until recently. It is kind of funny
that "solid state" was once a popular marketing term,
disappeared, and now reappears. I can't quite agree with
the person who called it marketing hype, since it's
a legitimate technical term. It's just that people
don't really recall what "solid state" was in contrast to.
Ben
|
| |
Date: 17 Jun 2007 19:03:16
From: Johnny Sunset
Subject: Re: What is a Solid State Emmiter?
|
On Jun 17, 8:35 pm, Bill Baka wrote:
> jim beam wrote:
> >http://hyperphysics.phy-astr.gsu.edu/hbase/solids/fermi.html
>
> Christ,
Does He read rec.bicycles.tech, and if so, would He respond to Bill
Baka?
> Now I'm going to start shit with you guys.
> Photons are a myth.
> Light is an electromagnetic phenomena but of a higher frequency than
> traditional radio.
> That much is simple.
> Photons CAN'T exist because light radiates in all directions, and one
> photon would be like a grain of sand going in one and only one direction.
> Normal light is radiated in all directions.
> My definition of a photon is one wavelength of light = 1 photon.
> Of course the Piled Higher and Deeper crowd will call me nuts, but they
> have earned the right to be wrong due to their 8 years of education,
> misled though it may be.
> If photons existed they would have to be of an infinite array of sizes
> to accommodate all the colors and wavelengths.
> Sorry, but photons aren't logical.
> Bill Baka, E.E., not Ph.D.
Bill Baka proves Albert Einstein wrong. Get the Nobel committee to
revoke his prize!!!
--
Tom Sherman - Holstein-Friesland Bovinia
The weather is here, wish you were beautiful
|
| | |
Date: 17 Jun 2007 22:04:27
From: Bill
Subject: Re: What is a Solid State Emmiter?
|
Johnny Sunset wrote:
> On Jun 17, 8:35 pm, Bill Baka wrote:
>> jim beam wrote:
>>> http://hyperphysics.phy-astr.gsu.edu/hbase/solids/fermi.html
>> Christ,
>
> Does He read rec.bicycles.tech, and if so, would He respond to Bill
> Baka?
>
>> Now I'm going to start shit with you guys.
>> Photons are a myth.
>> Light is an electromagnetic phenomena but of a higher frequency than
>> traditional radio.
>> That much is simple.
>> Photons CAN'T exist because light radiates in all directions, and one
>> photon would be like a grain of sand going in one and only one direction.
>> Normal light is radiated in all directions.
>> My definition of a photon is one wavelength of light = 1 photon.
>> Of course the Piled Higher and Deeper crowd will call me nuts, but they
>> have earned the right to be wrong due to their 8 years of education,
>> misled though it may be.
>> If photons existed they would have to be of an infinite array of sizes
>> to accommodate all the colors and wavelengths.
>> Sorry, but photons aren't logical.
>> Bill Baka, E.E., not Ph.D.
>
> Bill Baka proves Albert Einstein wrong. Get the Nobel committee to
> revoke his prize!!!
>
> --
> Tom Sherman - Holstein-Friesland Bovinia
> The weather is here, wish you were beautiful
>
>
I can't help it if he was working with flawed data, or if it is taught
as an unquestionable law in college. The concept of photons doesn't
work. It is just one unit of energy, as in one full wavelength.
What I learned in college was to question 'everything' or you would
never discover 'anything'. The sound barrier used to be regarded as
unbreakable and that any human who tried it would be killed by the
forces. Chuck Yeager proved that one wrong.
It may eventually be possible to travel faster than the speed of light,
but not for a few hundred years, if at all. How would you detour around
a space pebble at light speed++, since you would never see it?
A probe maybe, but a manned ship is unlikely.
Now think about those poor little photons traveling 14 billion light
years just for us to see in the Hubble space telescope.
Aren't we special?
Grow up. We don't have wings yet we fly. Is God pissed off at us?
Bill Baka
|
| |
Date: 16 Jun 2007 17:53:09
From: Johnny Sunset
Subject: Re: What is a Solid State Emmiter?
|
On Jun 16, 7:50 pm, datakoll aka gene daniels wrote:
> nixie! once upon, there was a vacuum tube emitting green light. for
> example, the closer to resonance with whatever, russian sub, american
> destroyer-the greener the tube became! far out no?
> during this period, immediately following the Cambrian, Asian
> languages failed exceeding surfaces technical translation, especially
> the south koreans, exceeding LV standup comedy surfaces from jungle
> jims to atom bomb assembly and ridiculed widely but mostly by the
> British who had moved to california. Chinese is not immune but
> pandemic, control is apparently violent.
INDEED!
--
Tom Sherman - Holstein-Friesland Bovinia
|
| |
Date: 17 Jun 2007 00:50:02
From: datakoll
Subject: Re: What is a Solid State Emmiter?
|
nixie! once upon, there was a vacuum tube emitting green light. for
example, the closer to resonance with whatever, russian sub, american
destroyer-the greener the tube became! far out no?
during this period, immediately following the Cambrian, Asian
languages failed exceeding surfaces technical translation, especially
the south koreans, exceeding LV standup comedy surfaces from jungle
jims to atom bomb assembly and ridiculed widely but mostly by the
British who had moved to california. Chinese is not immune but
pandemic, control is apparently violent.
|
| | |
Date: 16 Jun 2007 21:48:31
From: Bill
Subject: Re: What is a Solid State Emmiter?
|
datakoll wrote:
> nixie! once upon, there was a vacuum tube emitting green light. for
> example, the closer to resonance with whatever, russian sub, american
> destroyer-the greener the tube became! far out no?
> during this period, immediately following the Cambrian, Asian
> languages failed exceeding surfaces technical translation, especially
> the south koreans, exceeding LV standup comedy surfaces from jungle
> jims to atom bomb assembly and ridiculed widely but mostly by the
> British who had moved to california. Chinese is not immune but
> pandemic, control is apparently violent.
>
>
??????????????????????????
Bill Baka
|
| |
Date: 15 Jun 2007 19:23:42
From: jim beam
Subject: Re: What is a Solid State Emmiter?
|
aburdette@gmail.com wrote:
> Does anyone know what a solid state emitter is? Is it an LED? Is it
> like an LED?
>
> http://www.vetta.com/Product_Lights_nMini.htm
>
> Thanks,
>
> alan.
>
/that/ is an led. a "solid state emitter" could be a multitude of things.
|
| |
Date: 16 Jun 2007 01:57:27
From: Mike Lackey
Subject: Re: What is a Solid State Emmiter?
|
It's hard to know for sure, because no technical specs are given. But my
first impression is some marketing bozo is looking for a way to distinguish
his product from other LED lights by using the term "emitter" instad of
"light emitting diode". IMHO, more "buycycling" hype.
However, Luxeon was one of the fist to successfully market high-intensity
LED's, many of their products were designed to conveniently replace
flashlight bulbs. Google for Luxeon and it should become apparent. Perhaps
a "Super Lux" is some marketing bozo's attempt way of saying it's a
Luxeon-style LED.
One thing for sure, LED lights will only get better in the future, as
high-intensity technology (and optics) continue to both improve and come
down in price.
Mike Lackey
Madison, AL
<aburdette@gmail.com > wrote in message
news:1181925205.403818.64560@p77g2000hsh.googlegroups.com...
> Does anyone know what a solid state emitter is? Is it an LED? Is it
> like an LED?
>
> http://www.vetta.com/Product_Lights_nMini.htm
>
> Thanks,
>
> alan.
>
|
| | |
Date: 16 Jun 2007 19:27:23
From: Phil
Subject: Re: What is a Solid State Emmiter?
|
Mike Lackey wrote:
> It's hard to know for sure, because no technical specs are given. But my
> first impression is some marketing bozo is looking for a way
> to distinguish his product from other LED lights by using the term
> "emitter" instad of "light emitting diode". IMHO, more "buycycling"
> hype.
> However, Luxeon was one of the fist to successfully market
> high-intensity LED's, many of their products were designed to
> conveniently replace flashlight bulbs. Google for Luxeon and it
> should become apparent. Perhaps a "Super Lux" is some marketing
> bozo's attempt way of saying it's a Luxeon-style LED.
>
> One thing for sure, LED lights will only get better in the future, as
> high-intensity technology (and optics) continue to both improve and
> come down in price.
Luxeon is so last-generation. Check out Cree XR-Es. 60 lumens per watt at
1W? That's in the high range of fluorescent.
--
Phil
|
| | |
Date: 16 Jun 2007 10:04:53
From: A R:nen
Subject: Re: What is a Solid State Emmiter?
|
"Mike Lackey" <mr.blutarsky@mchsi.com > writes:
> It's hard to know for sure, because no technical specs are given. But my
> first impression is some marketing bozo is looking for a way to distinguish
> his product from other LED lights by using the term "emitter" instad of
> "light emitting diode".
But a diode only has an anode and a cathode, have they actually come
up with a light-emitting (garden-variety) transistor? No, I didn't
think so either. (Also, I'd like to see a vacuum tube LED, as opposed
to solid state. Ok, the heater does glow a bit, but that's about as
effective as using a cigarette as a light.)
|
| | | |
Date: 21 Jun 2007 03:52:05
From: Johnny Sunset
Subject: Re: What is a Solid State Emmiter?
|
On Jun 21, 12:20 am, Michael Press wrote:
> In article
> <6zjei.15375$2v1.7...@newssvr14.news.prodigy.net>,
>
> Bill Baka wrote:
> > Michael Press wrote:
> > > In article
> > > <MPG.20e253a3ef3feaf2989...@news.verizon.net>,
> > > RBrickston wrote:
>
> > >> In article <EOWdi.148$K44....@newssvr13.news.prodigy.net>,
> > >> b...@comcast.net says...
> > >>> I'm not bullshitting,
> > >> This would be a first.
>
> > >> <snipped the dumbest part>
>
> > >>> I think you just made my kill file.
> > >>> You are too obnoxious even for me.
> > >>> Bill Baka
>
> > >> Oh my, in Billy the Braggart's "killfile"... *such* a heartbreaker.
>
> > > How about I reply to all of your replies to Baka until
> > > he adds me to his kill-file?
>
> > 1. You haven't kill-filed Dolan yet?
> > 2. You got your wish since you choose to be the voice of arrogance.
> > Plonk!!
>
> Bravely bold Sir Robin rode forth from Camelot.
> He was not afraid to die, O brave Sir Robin.
> He was not at all afraid to be killed in nasty ways,
> Brave, brave, brave, brave Sir Robin!
>
> He was not in the least bit scared to be mashed into a pulp,
> Or to have his eyes gouged out and his elbows broken,
> To have his kneecaps split and his body burned away
> And his limbs all hacked and mangled, brave Sir Robin!
>
> His head smashed in and his heart cut out
> And his liver removed and his bowels unplugged
> And his nostrils raped and his bottom burned off
> And his ...
In the frozen land of Nador, they were forced to eat Robin's
minstrels.
And there was much rejoicing.
--
Tom Sherman - Holstein-Friesland Bovinia
The weather is here, wish you were beautiful
|
| | | | |
Date: 21 Jun 2007 10:01:48
From: RonSonic
Subject: Re: What is a Solid State Emmiter?
|
On Thu, 21 Jun 2007 03:52:05 -0700, Johnny Sunset <sunsetss0003@yahoo.com >
wrote:
>On Jun 21, 12:20 am, Michael Press wrote:
>> In article
>> <6zjei.15375$2v1.7...@newssvr14.news.prodigy.net>,
>>
>> Bill Baka wrote:
>> > Michael Press wrote:
>> > > In article
>> > > <MPG.20e253a3ef3feaf2989...@news.verizon.net>,
>> > > RBrickston wrote:
>>
>> > >> In article <EOWdi.148$K44....@newssvr13.news.prodigy.net>,
>> > >> b...@comcast.net says...
>> > >>> I'm not bullshitting,
>> > >> This would be a first.
>>
>> > >> <snipped the dumbest part>
>>
>> > >>> I think you just made my kill file.
>> > >>> You are too obnoxious even for me.
>> > >>> Bill Baka
>>
>> > >> Oh my, in Billy the Braggart's "killfile"... *such* a heartbreaker.
>>
>> > > How about I reply to all of your replies to Baka until
>> > > he adds me to his kill-file?
>>
>> > 1. You haven't kill-filed Dolan yet?
>> > 2. You got your wish since you choose to be the voice of arrogance.
>> > Plonk!!
>>
>> Bravely bold Sir Robin rode forth from Camelot.
>> He was not afraid to die, O brave Sir Robin.
>> He was not at all afraid to be killed in nasty ways,
>> Brave, brave, brave, brave Sir Robin!
>>
>> He was not in the least bit scared to be mashed into a pulp,
>> Or to have his eyes gouged out and his elbows broken,
>> To have his kneecaps split and his body burned away
>> And his limbs all hacked and mangled, brave Sir Robin!
>>
>> His head smashed in and his heart cut out
>> And his liver removed and his bowels unplugged
>> And his nostrils raped and his bottom burned off
>> And his ...
>
> In the frozen land of Nador, they were forced to eat Robin's
>minstrels.
>
> And there was much rejoicing.
Yeah.
Ron
|
| | | |
Date: 16 Jun 2007 16:10:38
From: Mike Lackey
Subject: Re: What is a Solid State Emmiter?
|
Vacuum tube LED = Nixie tube.
http://www.amug.org/~jthomas/watch.html
You may not be able to see where you're going, but you'll know the time.
Mike Lackey
Madison, AL
"A R:nen" <oronkain@ling.helsinki.fi > wrote in message
news:ysrxvedonzvu.fsf@ruuvi.it.helsinki.fi...
> "Mike Lackey" <mr.blutarsky@mchsi.com> writes:
>
>> It's hard to know for sure, because no technical specs are given. But my
>> first impression is some marketing bozo is looking for a way to
>> distinguish
>> his product from other LED lights by using the term "emitter" instad of
>> "light emitting diode".
>
> But a diode only has an anode and a cathode, have they actually come
> up with a light-emitting (garden-variety) transistor? No, I didn't
> think so either. (Also, I'd like to see a vacuum tube LED, as opposed
> to solid state. Ok, the heater does glow a bit, but that's about as
> effective as using a cigarette as a light.)
|
| | | | |
Date: 16 Jun 2007 09:27:51
From: jim beam
Subject: Re: What is a Solid State Emmiter?
|
Mike Lackey wrote:
> Vacuum tube LED = Nixie tube.
>
> http://www.amug.org/~jthomas/watch.html
now /that/ is rad!
>
> You may not be able to see where you're going, but you'll know the time.
>
> Mike Lackey
> Madison, AL
>
>
> "A R:nen" <oronkain@ling.helsinki.fi> wrote in message
> news:ysrxvedonzvu.fsf@ruuvi.it.helsinki.fi...
>> "Mike Lackey" <mr.blutarsky@mchsi.com> writes:
>>
>>> It's hard to know for sure, because no technical specs are given. But my
>>> first impression is some marketing bozo is looking for a way to
>>> distinguish
>>> his product from other LED lights by using the term "emitter" instad of
>>> "light emitting diode".
>> But a diode only has an anode and a cathode, have they actually come
>> up with a light-emitting (garden-variety) transistor? No, I didn't
>> think so either. (Also, I'd like to see a vacuum tube LED, as opposed
>> to solid state. Ok, the heater does glow a bit, but that's about as
>> effective as using a cigarette as a light.)
>
>
|
| | | |
Date: 16 Jun 2007 06:41:06
From: jim beam
Subject: Re: What is a Solid State Emmiter?
|
A R:nen wrote:
> "Mike Lackey" <mr.blutarsky@mchsi.com> writes:
>
>> It's hard to know for sure, because no technical specs are given. But my
>> first impression is some marketing bozo is looking for a way to distinguish
>> his product from other LED lights by using the term "emitter" instad of
>> "light emitting diode".
>
> But a diode only has an anode and a cathode, have they actually come
> up with a light-emitting (garden-variety) transistor? No, I didn't
> think so either.
actually, /all/ semicons emit light when they conduct, you just don't
usually get to see it because of the casing. and it's usually in the
infra-red spectrum.
> (Also, I'd like to see a vacuum tube LED, as opposed
> to solid state.
??? bizarre!
> Ok, the heater does glow a bit, but that's about as
> effective as using a cigarette as a light.)
you're not clear on the concept of what an led actually is.
|
| | | | |
Date: 17 Jun 2007 04:37:47
From: Bill
Subject: Re: What is a Solid State Emmiter?
|
jim beam wrote:
> A R:nen wrote:
>> "Mike Lackey" <mr.blutarsky@mchsi.com> writes:
>>
>>> It's hard to know for sure, because no technical specs are given.
>>> But my first impression is some marketing bozo is looking for a way
>>> to distinguish his product from other LED lights by using the term
>>> "emitter" instad of "light emitting diode".
>>
>> But a diode only has an anode and a cathode, have they actually come
>> up with a light-emitting (garden-variety) transistor? No, I didn't
>> think so either.
>
> actually, /all/ semicons emit light when they conduct, you just don't
> usually get to see it because of the casing. and it's usually in the
> infra-red spectrum.
>
>
>> (Also, I'd like to see a vacuum tube LED, as opposed
>> to solid state.
>
> ??? bizarre!
>
>> Ok, the heater does glow a bit, but that's about as
>> effective as using a cigarette as a light.)
>
> you're not clear on the concept of what an led actually is.
A vacuum tube LED is called a light bulb, except for the fact that it
does not use a vacuum but an inert gas so as to not oxidize the filament.
LED's are made up of all kinds of strange mixes of elements and rarely
use that much, if any, Silicon. There are Gallium-Arsenide,
Indium-Gallium-Arsenide, and enough to give me a headache just trying to
remember the combinations. There are even LASER LEDs made on big metal
heat sinks. Just Google LED manufacturers if you want an instant
headache. I work in electronics and gave up trying to memorize
everything over ten years ago. As the Internet matured, so did the
information overload. No one person, engineer, Einstein or not, can
possibly track all the stuff being done these days.
Just think of a light buld where the filament is NOT Tungsten.
Bill Baka
|
| | | | | |
Date: 16 Jun 2007 21:55:22
From: jim beam
Subject: Re: What is a Solid State Emmiter?
|
Bill wrote:
> jim beam wrote:
>> A R:nen wrote:
>>> "Mike Lackey" <mr.blutarsky@mchsi.com> writes:
>>>
>>>> It's hard to know for sure, because no technical specs are given.
>>>> But my first impression is some marketing bozo is looking for a way
>>>> to distinguish his product from other LED lights by using the term
>>>> "emitter" instad of "light emitting diode".
>>>
>>> But a diode only has an anode and a cathode, have they actually come
>>> up with a light-emitting (garden-variety) transistor? No, I didn't
>>> think so either.
>>
>> actually, /all/ semicons emit light when they conduct, you just don't
>> usually get to see it because of the casing. and it's usually in the
>> infra-red spectrum.
>>
>>
>>> (Also, I'd like to see a vacuum tube LED, as opposed
>>> to solid state.
>>
>> ??? bizarre!
>>
>>> Ok, the heater does glow a bit, but that's about as
>>> effective as using a cigarette as a light.)
>>
>> you're not clear on the concept of what an led actually is.
>
> A vacuum tube LED is called a light bulb
eh? incandescent filament bears as much resemblance to led as the
workings of an internal combustion engine do to nuclear fission. the
physics are /totally/ different.
>, except for the fact that it
> does not use a vacuum but an inert gas so as to not oxidize the filament.
> LED's are made up of all kinds of strange mixes of elements and rarely
> use that much, if any, Silicon. There are Gallium-Arsenide,
> Indium-Gallium-Arsenide, and enough to give me a headache just trying to
> remember the combinations. There are even LASER LEDs made on big metal
> heat sinks. Just Google LED manufacturers if you want an instant
> headache. I work in electronics and gave up trying to memorize
> everything over ten years ago. As the Internet matured, so did the
> information overload. No one person, engineer, Einstein or not, can
> possibly track all the stuff being done these days.
except that it's all searchable. and readable. if you can be bothered
before pronouncing in a way that evidences neither have been attempted.
> Just think of a light buld where the filament is NOT Tungsten.
http://www.centennialbulb.org/
|
| | | | | | |
Date: 17 Jun 2007 05:09:25
From: Bill
Subject: Re: What is a Solid State Emmiter?
|
jim beam wrote:
> Bill wrote:
>>
>> A vacuum tube LED is called a light bulb
>
> eh? incandescent filament bears as much resemblance to led as the
> workings of an internal combustion engine do to nuclear fission. the
> physics are /totally/ different.
That was a put on, as in joke. A triode is like a vacuum mode FET.
Depletion mode, but the same general idea. Make a cascode circuit with a
BJT on top and you have a fair imitation of a pentode. I am not trying
to be a serious source of information here.
>
>> , except for the fact that it does not use a vacuum but an inert gas
>> so as to not oxidize the filament.
>> LED's are made up of all kinds of strange mixes of elements and rarely
>> use that much, if any, Silicon. There are Gallium-Arsenide,
>> Indium-Gallium-Arsenide, and enough to give me a headache just trying
>> to remember the combinations. There are even LASER LEDs made on big
>> metal heat sinks. Just Google LED manufacturers if you want an instant
>> headache. I work in electronics and gave up trying to memorize
>> everything over ten years ago. As the Internet matured, so did the
>> information overload. No one person, engineer, Einstein or not, can
>> possibly track all the stuff being done these days.
>
> except that it's all searchable. and readable. if you can be bothered
> before pronouncing in a way that evidences neither have been attempted.
Out of a few dozen manufacturers who are all searching for the Holy
Grail of LEDs, there are probably a few dozen combinations of elements
that can be induced to produce some kind of light. I still have about
200 basic red LEDs from the 1970's that my employer gave to me when they
were cleaning house for "Inventory tax time". I have a key chain light
that uses a 1998 super bright (at the time) LED and a lithium battery
that a salesman gave to me at work, and it still works.
>
>
>> Just think of a light buld where the filament is NOT Tungsten.
>
> http://www.centennialbulb.org/
I heard of one in the firehouse in Palo Alto or somewhere in the Silicon
Valley area that had been on for over 100 years as of 1990 something.
Is that it?
BTW, the white LEDs in my Cat-Eye lamp run at 3.3 volts rather than the
typical 1.4 volts of the more common LEDs. Even that may not be safe to
say as geometries and compositions change seemingly week by week.
Bill Baka
|
| | | | | | | |
Date: 16 Jun 2007 22:31:34
From: jim beam
Subject: Re: What is a Solid State Emmiter?
|
Bill wrote:
> jim beam wrote:
>> Bill wrote:
>>>
>>> A vacuum tube LED is called a light bulb
>>
>> eh? incandescent filament bears as much resemblance to led as the
>> workings of an internal combustion engine do to nuclear fission. the
>> physics are /totally/ different.
>
> That was a put on, as in joke. A triode is like a vacuum mode FET.
> Depletion mode, but the same general idea. Make a cascode circuit with a
> BJT on top and you have a fair imitation of a pentode. I am not trying
> to be a serious source of information here.
no you're not. the physics are still way different. applications may
be analogous, but fission and combustion both produce heat.
>>
>>> , except for the fact that it does not use a vacuum but an inert gas
>>> so as to not oxidize the filament.
>>> LED's are made up of all kinds of strange mixes of elements and
>>> rarely use that much, if any, Silicon. There are Gallium-Arsenide,
>>> Indium-Gallium-Arsenide, and enough to give me a headache just trying
>>> to remember the combinations. There are even LASER LEDs made on big
>>> metal heat sinks. Just Google LED manufacturers if you want an
>>> instant headache. I work in electronics and gave up trying to
>>> memorize everything over ten years ago. As the Internet matured, so
>>> did the information overload. No one person, engineer, Einstein or
>>> not, can possibly track all the stuff being done these days.
>>
>> except that it's all searchable. and readable. if you can be
>> bothered before pronouncing in a way that evidences neither have been
>> attempted.
>
> Out of a few dozen manufacturers who are all searching for the Holy
> Grail of LEDs, there are probably a few dozen combinations of elements
> that can be induced to produce some kind of light. I still have about
> 200 basic red LEDs from the 1970's that my employer gave to me when they
> were cleaning house for "Inventory tax time". I have a key chain light
> that uses a 1998 super bright (at the time) LED and a lithium battery
> that a salesman gave to me at work, and it still works.
>>
>>
>>> Just think of a light buld where the filament is NOT Tungsten.
>>
>> http://www.centennialbulb.org/
>
> I heard of one in the firehouse in Palo Alto or somewhere in the Silicon
> Valley area that had been on for over 100 years as of 1990 something.
> Is that it?
>
> BTW, the white LEDs in my Cat-Eye lamp run at 3.3 volts rather than the
> typical 1.4 volts of the more common LEDs. Even that may not be safe to
> say as geometries and compositions change seemingly week by week.
> Bill Baka
bill, you cite band gaps, but how is it that you don't associate that
with operation voltage?
|
| | | | | | | | |
Date: 18 Jun 2007 01:19:09
From: Bill
Subject: Re: What is a Solid State Emmiter?
|
jim beam wrote:
> Bill wrote:
>> jim beam wrote:
>>> Bill wrote:
>>>>
>>>> A vacuum tube LED is called a light bulb
>>>
>>> eh? incandescent filament bears as much resemblance to led as the
>>> workings of an internal combustion engine do to nuclear fission. the
>>> physics are /totally/ different.
>>
>> That was a put on, as in joke. A triode is like a vacuum mode FET.
>> Depletion mode, but the same general idea. Make a cascode circuit with
>> a BJT on top and you have a fair imitation of a pentode. I am not
>> trying to be a serious source of information here.
>
> no you're not. the physics are still way different. applications may
> be analogous, but fission and combustion both produce heat.
>
>
>>>
>>>> , except for the fact that it does not use a vacuum but an inert gas
>>>> so as to not oxidize the filament.
>>>> LED's are made up of all kinds of strange mixes of elements and
>>>> rarely use that much, if any, Silicon. There are Gallium-Arsenide,
>>>> Indium-Gallium-Arsenide, and enough to give me a headache just
>>>> trying to remember the combinations. There are even LASER LEDs made
>>>> on big metal heat sinks. Just Google LED manufacturers if you want
>>>> an instant headache. I work in electronics and gave up trying to
>>>> memorize everything over ten years ago. As the Internet matured, so
>>>> did the information overload. No one person, engineer, Einstein or
>>>> not, can possibly track all the stuff being done these days.
>>>
>>> except that it's all searchable. and readable. if you can be
>>> bothered before pronouncing in a way that evidences neither have been
>>> attempted.
>>
>> Out of a few dozen manufacturers who are all searching for the Holy
>> Grail of LEDs, there are probably a few dozen combinations of elements
>> that can be induced to produce some kind of light. I still have about
>> 200 basic red LEDs from the 1970's that my employer gave to me when
>> they were cleaning house for "Inventory tax time". I have a key chain
>> light that uses a 1998 super bright (at the time) LED and a lithium
>> battery that a salesman gave to me at work, and it still works.
>>>
>>>
>>>> Just think of a light buld where the filament is NOT Tungsten.
>>>
>>> http://www.centennialbulb.org/
>>
>> I heard of one in the firehouse in Palo Alto or somewhere in the
>> Silicon Valley area that had been on for over 100 years as of 1990
>> something.
>> Is that it?
>>
>> BTW, the white LEDs in my Cat-Eye lamp run at 3.3 volts rather than
>> the typical 1.4 volts of the more common LEDs. Even that may not be
>> safe to say as geometries and compositions change seemingly week by week.
>> Bill Baka
>
> bill, you cite band gaps, but how is it that you don't associate that
> with operation voltage?
Probably because this is not the electronics engineering group?
That might be a bit overly tech, even here.
If I put pointers to all the manufacturers and the chemical makeup of
all the LEDs I can find, it will be a long list, and will anybody here
really care to visit all of those.
The key-chain light I got from a salesman back in 1998 or early 1999
still works and hasn't dimmed in 8 years. That one is Rohm.
The Jameco link below is only a start.
http://www.jameco.com/webapp/wcs/stores/servlet/CategoryDisplay?storeId=10001&catalogId=10001&langId=-1&categoryId=1520
Here is the high output section.
http://www.jameco.com/webapp/wcs/stores/servlet/CategoryDisplay?storeId=10001&catalogId=10001&langId=-1&categoryId=152020
Here's a RED one 630 nm and 1.8 volts.
http://www.jameco.com/webapp/wcs/stores/servlet/ProductDisplay?langId=-1&storeId=10001&catalogId=10001&productId=197616
Here's an Orange one at 634 nm and 2.3 volts.
http://www.jameco.com/webapp/wcs/stores/servlet/ProductDisplay?langId=-1&storeId=10001&catalogId=10001&productId=197683
Did you notice that only 4 nm makes the distinction between red and
orange? That's cutting it kind of close.
And here is a white at 3.5 volts.
http://www.jameco.com/webapp/wcs/stores/servlet/ProductDisplay?langId=-1&storeId=10001&catalogId=10001&productId=183231
There is also a link to a PDF file to show the wavelengths and
chemistry. This manufacturer, whom I have never heard of before, does
not use a simple LED to energize a flourescent to get white, as some
have suggested, but puts out a spectrum that is heavy on the blue end.
I could post more from Jameco, Mouser, Allied, etc....., until people
got sick of the subject.
Bill Baka
|
| | | | | | | | | |
Date: 18 Jun 2007 06:18:59
From: jim beam
Subject: Re: What is a Solid State Emmiter?
|
Bill wrote:
> jim beam wrote:
>> Bill wrote:
>>> jim beam wrote:
>>>> Bill wrote:
>>>>>
>>>>> A vacuum tube LED is called a light bulb
>>>>
>>>> eh? incandescent filament bears as much resemblance to led as the
>>>> workings of an internal combustion engine do to nuclear fission.
>>>> the physics are /totally/ different.
>>>
>>> That was a put on, as in joke. A triode is like a vacuum mode FET.
>>> Depletion mode, but the same general idea. Make a cascode circuit
>>> with a BJT on top and you have a fair imitation of a pentode. I am
>>> not trying to be a serious source of information here.
>>
>> no you're not. the physics are still way different. applications may
>> be analogous, but fission and combustion both produce heat.
>>
>>
>>>>
>>>>> , except for the fact that it does not use a vacuum but an inert
>>>>> gas so as to not oxidize the filament.
>>>>> LED's are made up of all kinds of strange mixes of elements and
>>>>> rarely use that much, if any, Silicon. There are Gallium-Arsenide,
>>>>> Indium-Gallium-Arsenide, and enough to give me a headache just
>>>>> trying to remember the combinations. There are even LASER LEDs made
>>>>> on big metal heat sinks. Just Google LED manufacturers if you want
>>>>> an instant headache. I work in electronics and gave up trying to
>>>>> memorize everything over ten years ago. As the Internet matured, so
>>>>> did the information overload. No one person, engineer, Einstein or
>>>>> not, can possibly track all the stuff being done these days.
>>>>
>>>> except that it's all searchable. and readable. if you can be
>>>> bothered before pronouncing in a way that evidences neither have
>>>> been attempted.
>>>
>>> Out of a few dozen manufacturers who are all searching for the Holy
>>> Grail of LEDs, there are probably a few dozen combinations of
>>> elements that can be induced to produce some kind of light. I still
>>> have about 200 basic red LEDs from the 1970's that my employer gave
>>> to me when they were cleaning house for "Inventory tax time". I have
>>> a key chain light that uses a 1998 super bright (at the time) LED and
>>> a lithium battery that a salesman gave to me at work, and it still
>>> works.
>>>>
>>>>
>>>>> Just think of a light buld where the filament is NOT Tungsten.
>>>>
>>>> http://www.centennialbulb.org/
>>>
>>> I heard of one in the firehouse in Palo Alto or somewhere in the
>>> Silicon Valley area that had been on for over 100 years as of 1990
>>> something.
>>> Is that it?
>>>
>>> BTW, the white LEDs in my Cat-Eye lamp run at 3.3 volts rather than
>>> the typical 1.4 volts of the more common LEDs. Even that may not be
>>> safe to say as geometries and compositions change seemingly week by
>>> week.
>>> Bill Baka
>>
>> bill, you cite band gaps, but how is it that you don't associate that
>> with operation voltage?
>
> Probably because this is not the electronics engineering group?
> That might be a bit overly tech, even here.
> If I put pointers to all the manufacturers and the chemical makeup of
> all the LEDs I can find, it will be a long list, and will anybody here
> really care to visit all of those.
> The key-chain light I got from a salesman back in 1998 or early 1999
> still works and hasn't dimmed in 8 years. That one is Rohm.
>
> The Jameco link below is only a start.
> http://www.jameco.com/webapp/wcs/stores/servlet/CategoryDisplay?storeId=10001&catalogId=10001&langId=-1&categoryId=1520
>
>
> Here is the high output section.
> http://www.jameco.com/webapp/wcs/stores/servlet/CategoryDisplay?storeId=10001&catalogId=10001&langId=-1&categoryId=152020
>
>
> Here's a RED one 630 nm and 1.8 volts.
> http://www.jameco.com/webapp/wcs/stores/servlet/ProductDisplay?langId=-1&storeId=10001&catalogId=10001&productId=197616
>
>
> Here's an Orange one at 634 nm and 2.3 volts.
> http://www.jameco.com/webapp/wcs/stores/servlet/ProductDisplay?langId=-1&storeId=10001&catalogId=10001&productId=197683
>
>
> Did you notice that only 4 nm makes the distinction between red and
> orange? That's cutting it kind of close.
>
> And here is a white at 3.5 volts.
> http://www.jameco.com/webapp/wcs/stores/servlet/ProductDisplay?langId=-1&storeId=10001&catalogId=10001&productId=183231
>
>
> There is also a link to a PDF file to show the wavelengths and
> chemistry. This manufacturer, whom I have never heard of before, does
> not use a simple LED to energize a flourescent to get white, as some
> have suggested, but puts out a spectrum that is heavy on the blue end.
>
> I could post more from Jameco, Mouser, Allied, etc....., until people
> got sick of the subject.
>
> Bill Baka
but that's the point! the larger the band gap, the larger the voltage
required! you change chemistry to change the band gap and voltage
varies accordingly!
|
| | | | | | | | | | |
Date: 18 Jun 2007 20:53:14
From: Bill
Subject: Re: What is a Solid State Emmiter?
|
jim beam wrote:
> Bill wrote:
>> And here is a white at 3.5 volts.
>> http://www.jameco.com/webapp/wcs/stores/servlet/ProductDisplay?langId=-1&storeId=10001&catalogId=10001&productId=183231
>>
>>
>> There is also a link to a PDF file to show the wavelengths and
>> chemistry. This manufacturer, whom I have never heard of before, does
>> not use a simple LED to energize a flourescent to get white, as some
>> have suggested, but puts out a spectrum that is heavy on the blue end.
>>
>> I could post more from Jameco, Mouser, Allied, etc....., until people
>> got sick of the subject.
>>
>> Bill Baka
>
>
> but that's the point! the larger the band gap, the larger the voltage
> required! you change chemistry to change the band gap and voltage
> varies accordingly!
I know that, but part of my point was that the number of chemistries is
growing as people search for real 'white' light, and not the blueish
tint that was shown in the pdf I pointed to, or a super efficient and
bright chemistry that will surpass all previous attempts. All of the
traffic lights in my somewhat backwater town have gone to single
wavelength red, yellow, green that can be seen even in bright sunlight.
I have only seen one light with one burned out LED in the green and they
don't see fit to replace it since it has been like that for over 2 years.
Mainstream LEDs emit in one very tight wavelength, kind of the light
version of a radio crystal.
Even I don't want to try to calculate the band gaps that are used all
over the map, like the Jameco part I referred to. That one tries to be
white and the spectrum is not a spike at one wavelength but a wide blue
tapering off on the red end of things. I had to download Chinese fonts
for my Acrobat just to see the whole data sheet, and I only want to
spend so much 'unpaid' time on research.
Pay me and I will make a spreadsheet of every LED ever made and the band
gaps of all the possible materials.
There are probably only a handful of people who care what makes the
light as long as it works.
I'm one since I have a Cat-Eye 5 LED setup with through hole white LEDs
and I might want to upgrade it if I can find some better white LEDs.
I was also thinking of building a miniature boost/buck universal
converter to drive the LEDs at whatever brightness I wanted to dial in
with an old fashioned pot. 3.3 volts on the LEDs, 4.8 volts from my NiMH
batteries, and 6 volts from Alkalines. I wouldn't mind sucking the
Alkalines for their last gasp, but the NiMH rechargeables might not like
that very much.
OK, enough electronic stuff.
Bill Baka
|
| | | | | | | | | | | |
Date: 18 Jun 2007 19:52:49
From: jim beam
Subject: Re: What is a Solid State Emmiter?
|
Bill wrote:
> jim beam wrote:
>> Bill wrote:
>>> And here is a white at 3.5 volts.
>>> http://www.jameco.com/webapp/wcs/stores/servlet/ProductDisplay?langId=-1&storeId=10001&catalogId=10001&productId=183231
>>>
>>>
>>> There is also a link to a PDF file to show the wavelengths and
>>> chemistry. This manufacturer, whom I have never heard of before, does
>>> not use a simple LED to energize a flourescent to get white, as some
>>> have suggested, but puts out a spectrum that is heavy on the blue end.
>>>
>>> I could post more from Jameco, Mouser, Allied, etc....., until people
>>> got sick of the subject.
>>>
>>> Bill Baka
>>
>>
>> but that's the point! the larger the band gap, the larger the voltage
>> required! you change chemistry to change the band gap and voltage
>> varies accordingly!
>
> I know that, but part of my point was that the number of chemistries is
> growing as people search for real 'white' light, and not the blueish
> tint that was shown in the pdf I pointed to, or a super efficient and
> bright chemistry that will surpass all previous attempts. All of the
> traffic lights in my somewhat backwater town have gone to single
> wavelength red, yellow, green that can be seen even in bright sunlight.
> I have only seen one light with one burned out LED in the green and they
> don't see fit to replace it since it has been like that for over 2 years.
> Mainstream LEDs emit in one very tight wavelength, kind of the light
> version of a radio crystal.
> Even I don't want to try to calculate the band gaps that are used all
> over the map, like the Jameco part I referred to. That one tries to be
> white and the spectrum is not a spike at one wavelength but a wide blue
> tapering off on the red end of things. I had to download Chinese fonts
> for my Acrobat just to see the whole data sheet, and I only want to
> spend so much 'unpaid' time on research.
> Pay me and I will make a spreadsheet of every LED ever made and the band
> gaps of all the possible materials.
so what? doesn't mean a thing if you don't understand what you're
looking at!
> There are probably only a handful of people who care what makes the
> light as long as it works.
> I'm one since I have a Cat-Eye 5 LED setup with through hole white LEDs
> and I might want to upgrade it if I can find some better white LEDs.
> I was also thinking of building a miniature boost/buck universal
> converter to drive the LEDs at whatever brightness I wanted to dial in
> with an old fashioned pot. 3.3 volts on the LEDs, 4.8 volts from my NiMH
> batteries, and 6 volts from Alkalines. I wouldn't mind sucking the
> Alkalines for their last gasp, but the NiMH rechargeables might not like
> that very much.
irrelevant.
> OK, enough electronic stuff.
please bill, please.
|
| | | | | | | | | | | | |
Date: 22 Jun 2007 22:06:07
From: Johnny Sunset
Subject: Re: What is a Solid State Emmiter?
|
On Jun 21, 9:01 am, RonSonic <ronso...@tampabay.rr.com > wrote:
> On Thu, 21 Jun 2007 03:52:05 -0700, Johnny Sunset <sunsetss0...@yahoo.com>
> wrote:
>
>
>
> >On Jun 21, 12:20 am, Michael Press wrote:
> >> In article
> >> <6zjei.15375$2v1.7...@newssvr14.news.prodigy.net>,
>
> >> Bill Baka wrote:
> >> > Michael Press wrote:
> >> > > In article
> >> > > <MPG.20e253a3ef3feaf2989...@news.verizon.net>,
> >> > > RBrickston wrote:
>
> >> > >> In article <EOWdi.148$K44....@newssvr13.news.prodigy.net>,
> >> > >> b...@comcast.net says...
> >> > >>> I'm not bullshitting,
> >> > >> This would be a first.
>
> >> > >> <snipped the dumbest part>
>
> >> > >>> I think you just made my kill file.
> >> > >>> You are too obnoxious even for me.
> >> > >>> Bill Baka
>
> >> > >> Oh my, in Billy the Braggart's "killfile"... *such* a heartbreaker.
>
> >> > > How about I reply to all of your replies to Baka until
> >> > > he adds me to his kill-file?
>
> >> > 1. You haven't kill-filed Dolan yet?
> >> > 2. You got your wish since you choose to be the voice of arrogance.
> >> > Plonk!!
>
> >> Bravely bold Sir Robin rode forth from Camelot.
> >> He was not afraid to die, O brave Sir Robin.
> >> He was not at all afraid to be killed in nasty ways,
> >> Brave, brave, brave, brave Sir Robin!
>
> >> He was not in the least bit scared to be mashed into a pulp,
> >> Or to have his eyes gouged out and his elbows broken,
> >> To have his kneecaps split and his body burned away
> >> And his limbs all hacked and mangled, brave Sir Robin!
>
> >> His head smashed in and his heart cut out
> >> And his liver removed and his bowels unplugged
> >> And his nostrils raped and his bottom burned off
> >> And his ...
>
> > In the frozen land of Nador, they were forced to eat Robin's
> >minstrels.
>
> > And there was much rejoicing.
>
> Yeah.
Ni!
--
Tom Sherman - Holstein-Friesland Bovinia
The weather is here, wish you were beautiful
|
| | | | | | | | | | | | |
Date: 18 Jun 2007 20:30:47
From: Bill
Subject: Re: What is a Solid State Emmiter?
|
jim beam wrote:
> Bill wrote:
>> jim beam wrote:
>>> Bill wrote:
>>>> And here is a white at 3.5 volts.
>>>> http://www.jameco.com/webapp/wcs/stores/servlet/ProductDisplay?langId=-1&storeId=10001&catalogId=10001&productId=183231
>>>>
>>>>
>>>> There is also a link to a PDF file to show the wavelengths and
>>>> chemistry. This manufacturer, whom I have never heard of before,
>>>> does not use a simple LED to energize a flourescent to get white, as
>>>> some have suggested, but puts out a spectrum that is heavy on the
>>>> blue end.
>>>>
>>>> I could post more from Jameco, Mouser, Allied, etc....., until
>>>> people got sick of the subject.
>>>>
>>>> Bill Baka
>>>
>>>
>>> but that's the point! the larger the band gap, the larger the
>>> voltage required! you change chemistry to change the band gap and
>>> voltage varies accordingly!
>>
>> I know that, but part of my point was that the number of chemistries
>> is growing as people search for real 'white' light, and not the
>> blueish tint that was shown in the pdf I pointed to, or a super
>> efficient and bright chemistry that will surpass all previous
>> attempts. All of the traffic lights in my somewhat backwater town have
>> gone to single wavelength red, yellow, green that can be seen even in
>> bright sunlight.
>> I have only seen one light with one burned out LED in the green and
>> they don't see fit to replace it since it has been like that for over
>> 2 years.
>> Mainstream LEDs emit in one very tight wavelength, kind of the light
>> version of a radio crystal.
>> Even I don't want to try to calculate the band gaps that are used all
>> over the map, like the Jameco part I referred to. That one tries to be
>> white and the spectrum is not a spike at one wavelength but a wide
>> blue tapering off on the red end of things. I had to download Chinese
>> fonts for my Acrobat just to see the whole data sheet, and I only want
>> to spend so much 'unpaid' time on research.
>> Pay me and I will make a spreadsheet of every LED ever made and the
>> band gaps of all the possible materials.
>
> so what? doesn't mean a thing if you don't understand what you're
> looking at!
I found out long ago that you can't learn everything and anyone who
claims to is either an idiot or lier. I'm an E.E. who just uses the
parts so I don't need to know all the band gaps. I do get paid for
designing circuits that use these parts and I am very money motivated.
>
>
>> There are probably only a handful of people who care what makes the
>> light as long as it works.
>> I'm one since I have a Cat-Eye 5 LED setup with through hole white
>> LEDs and I might want to upgrade it if I can find some better white LEDs.
>> I was also thinking of building a miniature boost/buck universal
>> converter to drive the LEDs at whatever brightness I wanted to dial in
>> with an old fashioned pot. 3.3 volts on the LEDs, 4.8 volts from my
>> NiMH batteries, and 6 volts from Alkalines. I wouldn't mind sucking
>> the Alkalines for their last gasp, but the NiMH rechargeables might
>> not like that very much.
>
> irrelevant.
Only if you want to buy new rechargeables every week. Kind of defeats
the purpose. I haven't seen any bicycle headlights that claimed to have
an active circuit for maximizing either battery life or brightness or
even just a level adjust other than a high/low resistor switch.
>
>
>> OK, enough electronic stuff.
>
> please bill, please.
>
>
How about enough physics stuff from you then?
Bill Baka
|
| | | | | | | | | | | | | |
Date: 18 Jun 2007 20:58:53
From: jim beam
Subject: Re: What is a Solid State Emmiter?
|
Bill wrote:
> jim beam wrote:
>> Bill wrote:
>>> jim beam wrote:
>>>> Bill wrote:
>>>>> And here is a white at 3.5 volts.
>>>>> http://www.jameco.com/webapp/wcs/stores/servlet/ProductDisplay?langId=-1&storeId=10001&catalogId=10001&productId=183231
>>>>>
>>>>>
>>>>> There is also a link to a PDF file to show the wavelengths and
>>>>> chemistry. This manufacturer, whom I have never heard of before,
>>>>> does not use a simple LED to energize a flourescent to get white,
>>>>> as some have suggested, but puts out a spectrum that is heavy on
>>>>> the blue end.
>>>>>
>>>>> I could post more from Jameco, Mouser, Allied, etc....., until
>>>>> people got sick of the subject.
>>>>>
>>>>> Bill Baka
>>>>
>>>>
>>>> but that's the point! the larger the band gap, the larger the
>>>> voltage required! you change chemistry to change the band gap and
>>>> voltage varies accordingly!
>>>
>>> I know that, but part of my point was that the number of chemistries
>>> is growing as people search for real 'white' light, and not the
>>> blueish tint that was shown in the pdf I pointed to, or a super
>>> efficient and bright chemistry that will surpass all previous
>>> attempts. All of the traffic lights in my somewhat backwater town
>>> have gone to single wavelength red, yellow, green that can be seen
>>> even in bright sunlight.
>>> I have only seen one light with one burned out LED in the green and
>>> they don't see fit to replace it since it has been like that for over
>>> 2 years.
>>> Mainstream LEDs emit in one very tight wavelength, kind of the light
>>> version of a radio crystal.
>>> Even I don't want to try to calculate the band gaps that are used all
>>> over the map, like the Jameco part I referred to. That one tries to
>>> be white and the spectrum is not a spike at one wavelength but a wide
>>> blue tapering off on the red end of things. I had to download Chinese
>>> fonts for my Acrobat just to see the whole data sheet, and I only
>>> want to spend so much 'unpaid' time on research.
>>> Pay me and I will make a spreadsheet of every LED ever made and the
>>> band gaps of all the possible materials.
>>
>> so what? doesn't mean a thing if you don't understand what you're
>> looking at!
>
> I found out long ago that you can't learn everything and anyone who
> claims to is either an idiot or lier.
ok...
> I'm an E.E. who just uses the
> parts so I don't need to know all the band gaps.
so how do you design if you don't know theory?
> I do get paid for
> designing circuits that use these parts
ok...
> and I am very money motivated.
that's logically irrelevant!
>>
>>
>>> There are probably only a handful of people who care what makes the
>>> light as long as it works.
>>> I'm one since I have a Cat-Eye 5 LED setup with through hole white
>>> LEDs and I might want to upgrade it if I can find some better white
>>> LEDs.
>>> I was also thinking of building a miniature boost/buck universal
>>> converter to drive the LEDs at whatever brightness I wanted to dial
>>> in with an old fashioned pot. 3.3 volts on the LEDs, 4.8 volts from
>>> my NiMH batteries, and 6 volts from Alkalines. I wouldn't mind
>>> sucking the Alkalines for their last gasp, but the NiMH rechargeables
>>> might not like that very much.
>>
>> irrelevant.
>
> Only if you want to buy new rechargeables every week. Kind of defeats
> the purpose. I haven't seen any bicycle headlights that claimed to have
> an active circuit for maximizing either battery life or brightness or
> even just a level adjust other than a high/low resistor switch.
it's irrelevant to led/incandescence differentiation!
>>
>>
>>> OK, enough electronic stuff.
>>
>> please bill, please.
>>
>>
> How about enough physics stuff from you then?
then stop bullshitting then! then.
|
| | | | | | | | | | | | | | |
Date: 19 Jun 2007 20:14:28
From: Bill
Subject: Re: What is a Solid State Emmiter?
|
jim beam wrote:
> Bill wrote:
>> jim beam wrote:
>>> Bill wrote:
>>
>> I found out long ago that you can't learn everything and anyone who
>> claims to is either an idiot or lier.
>
> ok...
>
>> I'm an E.E. who just uses the parts so I don't need to know all the
>> band gaps.
>
> so how do you design if you don't know theory?
All I need to know is that it puts out the light I need in the package I
need. I don't run to study the physics of a Mos-Fet before I decide to
design it in, as long as it is reliable. I know the 'theory' but I don't
need to research every LED and how much Silicon, Germanium, Gallium,
Arsenic, Indium, or whatever else is in the mix.
>
>
>> I do get paid for designing circuits that use these parts
>
> ok...
>
>> and I am very money motivated.
>
> that's logically irrelevant!
Only if you are a rich heir.
>
>
>>
>> Only if you want to buy new rechargeables every week. Kind of defeats
>> the purpose. I haven't seen any bicycle headlights that claimed to
>> have an active circuit for maximizing either battery life or
>> brightness or even just a level adjust other than a high/low resistor
>> switch.
>
> it's irrelevant to led/incandescence differentiation!
We've been over this.
>
>
>>>
>>>
>>>> OK, enough electronic stuff.
>>>
>>> please bill, please.
>>>
>>>
>> How about enough physics stuff from you then?
>
> then stop bullshitting then! then.
I'm not bullshitting, but you seem determined to make an ongoing debate
over that which is obvious. I could cheat and look up all the various
chemistries and then look up the element and quote you a bunch of
numbers that I could pick out of the periodic table and subsequent
references to that element and it's electron shells.
Do I want to take the time when I have a foot and a half pile of
electronics, physics, medical research journals, and other stuff to read?
No way do I put you on top of that list.
I think you just made my kill file.
You are too obnoxious even for me.
Bill Baka
|
| | | | | | | | | | | | | | | |
Date: 19 Jun 2007 21:03:50
From: jim beam
Subject: Re: What is a Solid State Emmiter?
|
Bill wrote:
> jim beam wrote:
>> Bill wrote:
>>> jim beam wrote:
>>>> Bill wrote:
>>>
>>> I found out long ago that you can't learn everything and anyone who
>>> claims to is either an idiot or lier.
>>
>> ok...
>>
>>> I'm an E.E. who just uses the parts so I don't need to know all the
>>> band gaps.
>>
>> so how do you design if you don't know theory?
>
> All I need to know is that it puts out the light I need in the package I
> need. I don't run to study the physics of a Mos-Fet before I decide to
> design it in, as long as it is reliable.
if you don't understand the theory, how are you going to figure out
whether you want bipolar, fet, or any of the hybrids?
> I know the 'theory' but I don't
> need to research every LED and how much Silicon, Germanium, Gallium,
> Arsenic, Indium, or whatever else is in the mix.
you don't need to know chemistry, but you need to know how they work!!!
>>
>>
>>> I do get paid for designing circuits that use these parts
>>
>> ok...
>>
>>> and I am very money motivated.
>>
>> that's logically irrelevant!
>
> Only if you are a rich heir.
>>
>>
>>>
>>> Only if you want to buy new rechargeables every week. Kind of defeats
>>> the purpose. I haven't seen any bicycle headlights that claimed to
>>> have an active circuit for maximizing either battery life or
>>> brightness or even just a level adjust other than a high/low resistor
>>> switch.
>>
>> it's irrelevant to led/incandescence differentiation!
>
> We've been over this.
translation: "i don't want to admit i don't know what i'm talking about".
>>
>>
>>>>
>>>>
>>>>> OK, enough electronic stuff.
>>>>
>>>> please bill, please.
>>>>
>>>>
>>> How about enough physics stuff from you then?
>>
>> then stop bullshitting then! then.
>
> I'm not bullshitting, but you seem determined to make an ongoing debate
> over that which is obvious. I could cheat and look up all the various
> chemistries and then look up the element and quote you a bunch of
> numbers that I could pick out of the periodic table and subsequent
> references to that element and it's electron shells.
it's not chemistry bill, it's physics. led's do not work by
incandescence. incandescents do not work by stimulated emissions.
> Do I want to take the time when I have a foot and a half pile of
> electronics, physics, medical research journals, and other stuff to read?
> No way do I put you on top of that list.
the only reason you have a pile is that you don't read it! as evidenced
by this thread!
> I think you just made my kill file.
> You are too obnoxious even for me.
> Bill Baka
perfect. thank you.
|
| | | | | | | | | | | | | | | |
Date: 20 Jun 2007 01:57:41
From: RBrickston
Subject: Re: What is a Solid State Emmiter?
|
In article <EOWdi.148$K44.110@newssvr13.news.prodigy.net >,
bbaka@comcast.net says...
> I'm not bullshitting,
This would be a first.
<snipped the dumbest part >
> I think you just made my kill file.
> You are too obnoxious even for me.
> Bill Baka
>
Oh my, in Billy the Braggart's "killfile"... *such* a heartbreaker.
|
| | | | | | | | | | | | | | | | |
Date: 20 Jun 2007 15:15:13
From: Michael Press
Subject: Re: What is a Solid State Emmiter?
|
In article
<MPG.20e253a3ef3feaf298968a@news.verizon.net >,
RBrickston <rb20170REMOVE@yahoo.com > wrote:
> In article <EOWdi.148$K44.110@newssvr13.news.prodigy.net>,
> bbaka@comcast.net says...
> > I'm not bullshitting,
>
> This would be a first.
>
> <snipped the dumbest part>
>
> > I think you just made my kill file.
> > You are too obnoxious even for me.
> > Bill Baka
> >
>
> Oh my, in Billy the Braggart's "killfile"... *such* a heartbreaker.
How about I reply to all of your replies to Baka until
he adds me to his kill-file?
--
Michael Press
|
| | | | | | | | | | | | | | | | | |
Date: 21 Jun 2007 00:24:34
From: Bill
Subject: Re: What is a Solid State Emmiter?
|
Michael Press wrote:
> In article
> <MPG.20e253a3ef3feaf298968a@news.verizon.net>,
> RBrickston <rb20170REMOVE@yahoo.com> wrote:
>
>> In article <EOWdi.148$K44.110@newssvr13.news.prodigy.net>,
>> bbaka@comcast.net says...
>>> I'm not bullshitting,
>> This would be a first.
>>
>> <snipped the dumbest part>
>>
>>> I think you just made my kill file.
>>> You are too obnoxious even for me.
>>> Bill Baka
>>>
>> Oh my, in Billy the Braggart's "killfile"... *such* a heartbreaker.
>
> How about I reply to all of your replies to Baka until
> he adds me to his kill-file?
>
1. You haven't kill-filed Dolan yet?
2. You got your wish since you choose to be the voice of arrogance.
Plonk!!
|
| | | | | | | | | | | | | | | | | | |
Date: 20 Jun 2007 22:20:40
From: Michael Press
Subject: Re: What is a Solid State Emmiter?
|
In article
<6zjei.15375$2v1.7738@newssvr14.news.prodigy.net >,
Bill <bbaka@comcast.net > wrote:
> Michael Press wrote:
> > In article
> > <MPG.20e253a3ef3feaf298968a@news.verizon.net>,
> > RBrickston <rb20170REMOVE@yahoo.com> wrote:
> >
> >> In article <EOWdi.148$K44.110@newssvr13.news.prodigy.net>,
> >> bbaka@comcast.net says...
> >>> I'm not bullshitting,
> >> This would be a first.
> >>
> >> <snipped the dumbest part>
> >>
> >>> I think you just made my kill file.
> >>> You are too obnoxious even for me.
> >>> Bill Baka
> >>>
> >> Oh my, in Billy the Braggart's "killfile"... *such* a heartbreaker.
> >
> > How about I reply to all of your replies to Baka until
> > he adds me to his kill-file?
> >
> 1. You haven't kill-filed Dolan yet?
> 2. You got your wish since you choose to be the voice of arrogance.
> Plonk!!
Bravely bold Sir Robin rode forth from Camelot.
He was not afraid to die, O brave Sir Robin.
He was not at all afraid to be killed in nasty ways,
Brave, brave, brave, brave Sir Robin!
He was not in the least bit scared to be mashed into a pulp,
Or to have his eyes gouged out and his elbows broken,
To have his kneecaps split and his body burned away
And his limbs all hacked and mangled, brave Sir Robin!
His head smashed in and his heart cut out
And his liver removed and his bowels unplugged
And his nostrils raped and his bottom burned off
And his ...
--
Michael Press
|
| | | | | | | | | | |
Date: 18 Jun 2007 15:09:55
From: RBrickston
Subject: Re: What is a Solid State Emmiter?
|
In article <0d6dnW_bt6_eG-vbnZ2dnUVZ_qXinZ2d@speakeasy.net >,
spamvortex@bad.example.net says...
> Bill wrote:
<mercy snip >
> >
> > There is also a link to a PDF file to show the wavelengths and
> > chemistry. This manufacturer, whom I have never heard of before, does
> > not use a simple LED to energize a flourescent to get white, as some
> > have suggested, but puts out a spectrum that is heavy on the blue end.
> >
> > I could post more from Jameco, Mouser, Allied, etc....., until people
> > got sick of the subject.
> >
> > Bill Baka
>
>
> but that's the point! the larger the band gap, the larger the voltage
> required! you change chemistry to change the band gap and voltage
> varies accordingly!
>
Baka's post just proves that he's a regurgitator of information found on
the web; and he's not very good at it. Bottom line: not a wisp of
original thought, unless he's making something up about himself.
|
| | | | |
Date: 16 Jun 2007 18:28:32
From: Peter Cole
Subject: Re: What is a Solid State Emmiter?
|
jim beam wrote:
> actually, /all/ semicons emit light when they conduct, you just don't
> usually get to see it because of the casing. and it's usually in the
> infra-red spectrum.
I'm afraid you're quite wrong.
http://en.wikipedia.org/wiki/Led :
"The wavelength of the light emitted, and therefore its colour, depends
on the band gap energy of the materials forming the p-n junction. In
silicon or germanium diodes, the electrons and holes recombine by a
non-radiative transition which produces no optical emission, because
these are indirect band gap materials. The materials used for an LED
have a direct band gap with energies corresponding to near-infrared,
visible or near-ultraviolet light."
|
| | | | | |
Date: 16 Jun 2007 20:30:02
From: jim beam
Subject: Re: What is a Solid State Emmiter?
|
Peter Cole wrote:
> jim beam wrote:
>
>> actually, /all/ semicons emit light when they conduct, you just don't
>> usually get to see it because of the casing. and it's usually in the
>> infra-red spectrum.
>
> I'm afraid you're quite wrong.
no, i'm quite right. re-read my post. "light" isn't just visible.
>
> http://en.wikipedia.org/wiki/Led :
>
> "The wavelength of the light emitted, and therefore its colour, depends
> on the band gap energy of the materials forming the p-n junction. In
> silicon or germanium diodes, the electrons and holes recombine by a
> non-radiative transition which produces no optical
note: OPTICAL.
> emission, because
> these are indirect band gap materials. The materials used for an LED
> have a direct band gap with energies corresponding to near-infrared,
> visible or near-ultraviolet light."
that's why i said infra-red. normal semiconductors emit in infra-red.
with chemistry, you can tune the band gap to optical energies, and thus
get visible emissions. but you don't do that for standard semicons!
look up the band gap energies and correlate them to emission spectrum.
|
| | | | | | |
Date: 17 Jun 2007 17:46:40
From: Peter Cole
Subject: Re: What is a Solid State Emmiter?
|
jim beam wrote:
> Peter Cole wrote:
>> jim beam wrote:
>>
>>> actually, /all/ semicons emit light when they conduct, you just don't
>>> usually get to see it because of the casing. and it's usually in the
>>> infra-red spectrum.
>>
>> I'm afraid you're quite wrong.
>
> no, i'm quite right. re-read my post. "light" isn't just visible.
>
>>
>> http://en.wikipedia.org/wiki/Led :
>>
>> "The wavelength of the light emitted, and therefore its colour,
>> depends on the band gap energy of the materials forming the p-n
>> junction. In silicon or germanium diodes, the electrons and holes
>> recombine by a non-radiative transition which produces no optical
>
> note: OPTICAL.
>
>> emission, because these are indirect band gap materials. The materials
>> used for an LED have a direct band gap with energies corresponding to
>> near-infrared, visible or near-ultraviolet light."
>
> that's why i said infra-red. normal semiconductors emit in infra-red.
> with chemistry, you can tune the band gap to optical energies, and thus
> get visible emissions. but you don't do that for standard semicons!
> look up the band gap energies and correlate them to emission spectrum.
Actually, you're still wrong. Originally you said "all semiconductors
emit light", which is wrong.
Now you say "normal semiconductors emit in the infra-red". I'm not at
all sure what you mean by "normal". Infra-red light is still light
(photons).
If you consider silicon and germanium to be "normal", then no, they
don't emit light typically during the process of recombination (e.g.
current flow through a p-n junction, the process which causes LED's to
emit photons (on a variety of wavelengths).
In silicon and other "indirect bandgap" materials, the energy of
recombination is released via phonons rather than photons.
photons = optical = light.
phonons are not photons.
|
| | | | | | | |
Date: 18 Jun 2007 07:45:37
From: =?ISO-8859-1?Q?G=FCnther?= Schwarz
Subject: Re: What is a Solid State Emmiter?
|
Peter Cole wrote:
> jim beam wrote:
>> that's why i said infra-red. normal semiconductors emit in
>> infra-red. with chemistry, you can tune the band gap to optical
>> energies, and thus
>> get visible emissions. but you don't do that for standard semicons!
> Actually, you're still wrong. Originally you said "all semiconductors
> emit light", which is wrong.
>
> Now you say "normal semiconductors emit in the infra-red". I'm not at
> all sure what you mean by "normal". Infra-red light is still light
> (photons).
>
> If you consider silicon and germanium to be "normal", then no, they
> don't emit light typically during the process of recombination (e.g.
> current flow through a p-n junction, the process which causes LED's to
> emit photons (on a variety of wavelengths).
>
> In silicon and other "indirect bandgap" materials, the energy of
> recombination is released via phonons rather than photons.
Sorry Peter, but with all the BS jb writes in this thread he is
obviously a hopeless case. Teaching an empty bottle calculus will be
easier than correcting all this nonsense. It hurts to read it, so I
won't go through all of it.
The only thing he is right about is that all semiconductor devices are
at ambient temperature when not in use and heat up during operation. So
they emit black body radiation. To make use of this effect for lighting
applications Edison commercialized the light bulb. A much more
practical device than silicon above the melting temperature for
lighting up your home place :-)
Günther
|
| | | | | | | | |
Date: 18 Jun 2007 06:17:11
From: jim beam
Subject: Re: What is a Solid State Emmiter?
|
� Schwarz wrote:
> Peter Cole wrote:
>
>> jim beam wrote:
>
>>> that's why i said infra-red. normal semiconductors emit in
>>> infra-red. with chemistry, you can tune the band gap to optical
>>> energies, and thus
>>> get visible emissions. but you don't do that for standard semicons!
>
>> Actually, you're still wrong. Originally you said "all semiconductors
>> emit light", which is wrong.
>>
>> Now you say "normal semiconductors emit in the infra-red". I'm not at
>> all sure what you mean by "normal". Infra-red light is still light
>> (photons).
>>
>> If you consider silicon and germanium to be "normal", then no, they
>> don't emit light typically during the process of recombination (e.g.
>> current flow through a p-n junction, the process which causes LED's to
>> emit photons (on a variety of wavelengths).
>>
>> In silicon and other "indirect bandgap" materials, the energy of
>> recombination is released via phonons rather than photons.
>
> Sorry Peter, but with all the BS jb writes in this thread he is
> obviously a hopeless case. Teaching an empty bottle calculus will be
> easier than correcting all this nonsense. It hurts to read it, so I
> won't go through all of it.
> The only thing he is right about is that all semiconductor devices are
> at ambient temperature when not in use and heat up during operation. So
> they emit black body radiation. To make use of this effect for lighting
> applications Edison commercialized the light bulb. A much more
> practical device than silicon above the melting temperature for
> lighting up your home place :-)
>
> Günther
eh? anything above 0K emits black body radiation!
|
| | | | | | | | | |
Date: 18 Jun 2007 20:43:05
From: =?ISO-8859-1?Q?G=FCnther?= Schwarz
Subject: Re: What is a Solid State Emmiter?
|
jim beam wrote:
> � Schwarz wrote:
>> Peter Cole wrote:
>>
>>> jim beam wrote:
>>> In silicon and other "indirect bandgap" materials, the energy of
>>> recombination is released via phonons rather than photons.
>>
>> Sorry Peter, but with all the BS jb writes in this thread he is
>> obviously a hopeless case.
>> The only thing he is right about is that all semiconductor devices
>> are at ambient temperature when not in use and heat up during
>> operation. So they emit black body radiation.
> eh? anything above 0K emits black body radiation!
Bingo, you've got my point. As Peter already explained with much more
patience than I have a silicon based device is as interesting as a cup
of coffee as far as the emission of electromagnetic radiation is
concerned.
And just in case some experts want to jump in here: There are effects
like transitions in core levels which involve the emissions of photons.
There also have been serious and ongoing efforts in building a silicon
based laser, IIRC mostly by exploiting finite size effects to shape the
band structure. Up to now with no convincing success. I consider none
of this to be relevant for this discussion.
Günther
|
| | | | | | | | | | |
Date: 18 Jun 2007 19:44:32
From: jim beam
Subject: Re: What is a Solid State Emmiter?
|
� Schwarz wrote:
> jim beam wrote:
>
>> � Schwarz wrote:
>>> Peter Cole wrote:
>>>
>>>> jim beam wrote:
>
>>>> In silicon and other "indirect bandgap" materials, the energy of
>>>> recombination is released via phonons rather than photons.
>>> Sorry Peter, but with all the BS jb writes in this thread he is
>>> obviously a hopeless case.
>
>>> The only thing he is right about is that all semiconductor devices
>>> are at ambient temperature when not in use and heat up during
>>> operation. So they emit black body radiation.
>
>> eh? anything above 0K emits black body radiation!
>
> Bingo, you've got my point. As Peter already explained with much more
> patience than I have a silicon based device is as interesting as a cup
> of coffee as far as the emission of electromagnetic radiation is
> concerned.
> And just in case some experts want to jump in here: There are effects
> like transitions in core levels which involve the emissions of photons.
that's what i keep trying to have you guys understand!!!
> There also have been serious and ongoing efforts in building a silicon
> based laser, IIRC mostly by exploiting finite size effects to shape the
> band structure. Up to now with no convincing success.
eh?
http://www.mtmi.vu.lt/pfk/funkc_dariniai/diod/led.htm
and dopant is not substrate.
> I consider none
> of this to be relevant for this discussion.
>
> Günther
|
| | | | | | | | | | | |
Date: 19 Jun 2007 07:58:24
From: =?ISO-8859-1?Q?G=FCnther?= Schwarz
Subject: Re: What is a Solid State Emmiter?
|
jim beam wrote:
> � Schwarz wrote:
>> And just in case some experts want to jump in here: There are effects
>> like transitions in core levels which involve the emissions of
>> photons.
>
> that's what i keep trying to have you guys understand!!!
I can't comment on all the stuff you posted about mechanics and
metallurgy on rbt, but on semiconductors you have proven to be
completely ignorant. Get a good textbook about semiconductor physics
and then come back. EOD.
Günther
|
| | | | | | | | | | | | |
Date: 19 Jun 2007 21:05:04
From: jim beam
Subject: Re: What is a Solid State Emmiter?
|
� Schwarz wrote:
> jim beam wrote:
>
>> � Schwarz wrote:
>
>>> And just in case some experts want to jump in here: There are effects
>>> like transitions in core levels which involve the emissions of
>>> photons.
>> that's what i keep trying to have you guys understand!!!
>
> I can't comment on all the stuff you posted about mechanics and
> metallurgy on rbt, but on semiconductors you have proven to be
> completely ignorant. Get a good textbook about semiconductor physics
> and then come back. EOD.
>
> Günther
>
the energy released in electron "demotion" is by photon emission. the
energy of that photon is determined by the level at which it started and
to which it drops. the larger the drop, the more energetic the emission.
|
| | | | | | | | | | | |
Date: 18 Jun 2007 20:22:05
From: Bill
Subject: Re: What is a Solid State Emmiter?
|
jim beam wrote:
> � Schwarz wrote:
>> There also have been serious and ongoing efforts in building a silicon
>> based laser, IIRC mostly by exploiting finite size effects to shape the
>> band structure. Up to now with no convincing success.
>
> eh?
>
> http://www.mtmi.vu.lt/pfk/funkc_dariniai/diod/led.htm
>
> and dopant is not substrate.
>
I snipped somebody but....
There was a semi-based laser built into a TO-3 power transistor shell
about ten years back but I never did anything more than look at the data
sheet, so they could be real (or not). In 2001 I was involved in
military work for the UAVs that have become so popular and the targeting
and range finding laser used about 400 volts so I am guessing it wasn't
a diode.
Beyond that I claim ignorance since I am not working with them now.
Bill Baka
|
| | | | | | | |
Date: 17 Jun 2007 15:10:19
From: jim beam
Subject: Re: What is a Solid State Emmiter?
|
Peter Cole wrote:
> jim beam wrote:
>> Peter Cole wrote:
>>> jim beam wrote:
>>>
>>>> actually, /all/ semicons emit light when they conduct, you just
>>>> don't usually get to see it because of the casing. and it's usually
>>>> in the infra-red spectrum.
>>>
>>> I'm afraid you're quite wrong.
>>
>> no, i'm quite right. re-read my post. "light" isn't just visible.
>>
>>>
>>> http://en.wikipedia.org/wiki/Led :
>>>
>>> "The wavelength of the light emitted, and therefore its colour,
>>> depends on the band gap energy of the materials forming the p-n
>>> junction. In silicon or germanium diodes, the electrons and holes
>>> recombine by a non-radiative transition which produces no optical
>>
>> note: OPTICAL.
>>
>>> emission, because these are indirect band gap materials. The
>>> materials used for an LED have a direct band gap with energies
>>> corresponding to near-infrared, visible or near-ultraviolet light."
>>
>> that's why i said infra-red. normal semiconductors emit in infra-red.
>> with chemistry, you can tune the band gap to optical energies, and
>> thus get visible emissions. but you don't do that for standard
>> semicons! look up the band gap energies and correlate them to emission
>> spectrum.
>
> Actually, you're still wrong. Originally you said "all semiconductors
> emit light", which is wrong.
infrared /is/ light. if you want to be more precise, maybe i could have
stated it as "all semiconductors emit electromagnetic radiation as
excited electrons drop to a less excited state". but that emission is
still "light" as a function of band gap energy and therefore frequency.
>
> Now you say "normal semiconductors emit in the infra-red". I'm not at
> all sure what you mean by "normal". Infra-red light is still light
> (photons).
infrared /is/ light - that's what i've been saying!
>
> If you consider silicon and germanium to be "normal", then no, they
> don't emit light typically during the process of recombination (e.g.
> current flow through a p-n junction, the process which causes LED's to
> emit photons (on a variety of wavelengths).
they emit infrared!!! and the wavelength is very precise as a function
of energy gap.
>
> In silicon and other "indirect bandgap" materials, the energy of
> recombination is released via phonons rather than photons.
phonons are a function of atomic vibration - completely different from
electromagnetic radiation from within an atom's electron orbits.
>
> photons = optical = light.
>
> phonons are not photons.
indeed. photons are electromagnetic. electrons decaying from a high
energy to a low one emit electromagnetic energy - photons. the
frequency of which is a function of the energy drop.
http://hyperphysics.phy-astr.gsu.edu/hbase/solids/fermi.html
|
| | | | | | | | |
Date: 18 Jun 2007 07:15:10
From: Peter Cole
Subject: Re: What is a Solid State Emmiter?
|
jim beam wrote:
> Peter Cole wrote:
>> If you consider silicon and germanium to be "normal", then no, they
>> don't emit light typically during the process of recombination (e.g.
>> current flow through a p-n junction, the process which causes LED's to
>> emit photons (on a variety of wavelengths).
>
> they emit infrared!!! and the wavelength is very precise as a function
> of energy gap.
No, they do not. You are mistaken. Indirect bandgap materials require a
change in both electron energy and momentum to move from valence to
conduction band. Photon emission doesn't provide the necessary change in
momentum.
|
| | | | | | | | | |
Date: 18 Jun 2007 06:16:07
From: jim beam
Subject: Re: What is a Solid State Emmiter?
|
Peter Cole wrote:
> jim beam wrote:
>> Peter Cole wrote:
>
>>> If you consider silicon and germanium to be "normal", then no, they
>>> don't emit light typically during the process of recombination (e.g.
>>> current flow through a p-n junction, the process which causes LED's
>>> to emit photons (on a variety of wavelengths).
>>
>> they emit infrared!!! and the wavelength is very precise as a
>> function of energy gap.
>
> No, they do not. You are mistaken. Indirect bandgap materials require a
> change in both electron energy and momentum to move from valence to
> conduction band. Photon emission doesn't provide the necessary change in
> momentum.
so why didn't fermi pick up on that then? all my laser science would be
up s-creek without him.
|
| | | | | | | | | | |
Date: 18 Jun 2007 12:04:55
From: Peter Cole
Subject: Re: What is a Solid State Emmiter?
|
jim beam wrote:
> Peter Cole wrote:
>> jim beam wrote:
>>> Peter Cole wrote:
>>
>>>> If you consider silicon and germanium to be "normal", then no, they
>>>> don't emit light typically during the process of recombination (e.g.
>>>> current flow through a p-n junction, the process which causes LED's
>>>> to emit photons (on a variety of wavelengths).
>>>
>>> they emit infrared!!! and the wavelength is very precise as a
>>> function of energy gap.
>>
>> No, they do not. You are mistaken. Indirect bandgap materials require
>> a change in both electron energy and momentum to move from valence to
>> conduction band. Photon emission doesn't provide the necessary change
>> in momentum.
>
> so why didn't fermi pick up on that then? all my laser science would be
> up s-creek without him.
This was originally published in 1952 by Shockley and Reid, and in the
same year (independently) by Hall. You're just a little out of date.
|
| | | | | | | | |
Date: 18 Jun 2007 01:35:13
From: Bill
Subject: Re: What is a Solid State Emmiter?
|
jim beam wrote:
> http://hyperphysics.phy-astr.gsu.edu/hbase/solids/fermi.html
Christ,
Now I'm going to start shit with you guys.
Photons are a myth.
Light is an electromagnetic phenomena but of a higher frequency than
traditional radio.
That much is simple.
Photons CAN'T exist because light radiates in all directions, and one
photon would be like a grain of sand going in one and only one direction.
Normal light is radiated in all directions.
My definition of a photon is one wavelength of light = 1 photon.
Of course the Piled Higher and Deeper crowd will call me nuts, but they
have earned the right to be wrong due to their 8 years of education,
misled though it may be.
If photons existed they would have to be of an infinite array of sizes
to accommodate all the colors and wavelengths.
Sorry, but photons aren't logical.
Bill Baka, E.E., not Ph.D.
|
| | | | | | | | | |
Date: 18 Jun 2007 03:42:14
From: RBrickston
Subject: Re: What is a Solid State Emmiter?
|
In article <ljldi.14836$RX.10727@newssvr11.news.prodigy.net >,
bbaka@comcast.net says...
> jim beam wrote:
> > http://hyperphysics.phy-astr.gsu.edu/hbase/solids/fermi.html
>
> Christ,
> Now I'm going to start shit with you guys.
> Photons are a myth.
> Light is an electromagnetic phenomena but of a higher frequency than
> traditional radio.
> That much is simple.
> Photons CAN'T exist because light radiates in all directions, and one
> photon would be like a grain of sand going in one and only one direction.
> Normal light is radiated in all directions.
> My definition of a photon is one wavelength of light = 1 photon.
> Of course the Piled Higher and Deeper crowd will call me nuts, but they
> have earned the right to be wrong due to their 8 years of education,
> misled though it may be.
> If photons existed they would have to be of an infinite array of sizes
> to accommodate all the colors and wavelengths.
> Sorry, but photons aren't logical.
> Bill Baka, E.E., not Ph.D.
0 1 2 3 4 5 6 7 8 9 10 +10dB
|
| | | | | | |
Date: 16 Jun 2007 21:47:20
From: Bill
Subject: Re: What is a Solid State Emmiter?
|
jim beam wrote:
> Peter Cole wrote:
>> jim beam wrote:
>>
>>> actually, /all/ semicons emit light when they conduct, you just don't
>>> usually get to see it because of the casing. and it's usually in the
>>> infra-red spectrum.
>>
>> I'm afraid you're quite wrong.
>
> no, i'm quite right. re-read my post. "light" isn't just visible.
>
>>
>> http://en.wikipedia.org/wiki/Led :
>>
>> "The wavelength of the light emitted, and therefore its colour,
>> depends on the band gap energy of the materials forming the p-n
>> junction. In silicon or germanium diodes, the electrons and holes
>> recombine by a non-radiative transition which produces no optical
>
> note: OPTICAL.
>
>> emission, because these are indirect band gap materials. The materials
>> used for an LED have a direct band gap with energies corresponding to
>> near-infrared, visible or near-ultraviolet light."
>
> that's why i said infra-red. normal semiconductors emit in infra-red.
> with chemistry, you can tune the band gap to optical energies, and thus
> get visible emissions. but you don't do that for standard semicons!
> look up the band gap energies and correlate them to emission spectrum.
Hey, guys....
Heat is infra-red. Extremely infra-red becomes ultra high frequency
radio waves. The different colors of LEDs are due to the band-gap
energies involved in the chemical cocktail used to make the LED.
Each blend puts out light in a very narrow, almost spike, wavelength.
Red is around 750nM and Blue near UV is around 400nM, or 0.4 microns.
The human eye (retina) can detect down to 300nM but the lens cuts out
the light up to about 400nM. I didn't look this up, but Isaac Asimov
mentioned that a friend had cataract surgery and could see shades of
purple that others could only imagine. It was in the preface of one of
his sci-fi books around 1960. He was not only a writer but a real
professor, so I think that one would prove to be true. Finding a
reference might be a bit rough, but the Opthalmology association should
mention it somewhere.
Super high frequency radio == infra-red.
Super infra-red == ultra UHF radio.
Simple?
Bill Baka
|
| | | | | | | |
Date: 17 Jun 2007 20:13:35
From: Friday
Subject: Re: What is a Solid State Emmiter?
|
Bill wrote:
> jim beam wrote:
>> Peter Cole wrote:
>>> jim beam wrote:
>>>
>>>> actually, /all/ semicons emit light when they conduct, you just
>>>> don't usually get to see it because of the casing. and it's usually
>>>> in the infra-red spectrum.
>>>
>>> I'm afraid you're quite wrong.
>>
>> no, i'm quite right. re-read my post. "light" isn't just visible.
>>
>>>
>>> http://en.wikipedia.org/wiki/Led :
>>>
>>> "The wavelength of the light emitted, and therefore its colour,
>>> depends on the band gap energy of the materials forming the p-n
>>> junction. In silicon or germanium diodes, the electrons and holes
>>> recombine by a non-radiative transition which produces no optical
>>
>> note: OPTICAL.
>>
>>> emission, because these are indirect band gap materials. The
>>> materials used for an LED have a direct band gap with energies
>>> corresponding to near-infrared, visible or near-ultraviolet light."
>>
>> that's why i said infra-red. normal semiconductors emit in infra-red.
>> with chemistry, you can tune the band gap to optical energies, and
>> thus get visible emissions. but you don't do that for standard
>> semicons! look up the band gap energies and correlate them to emission
>> spectrum.
>
>
> Hey, guys....
> Heat is infra-red. Extremely infra-red becomes ultra high frequency
> radio waves. The different colors of LEDs are due to the band-gap
> energies involved in the chemical cocktail used to make the LED.
> Each blend puts out light in a very narrow, almost spike, wavelength.
> Red is around 750nM and Blue near UV is around 400nM, or 0.4 microns.
> The human eye (retina) can detect down to 300nM but the lens cuts out
> the light up to about 400nM. I didn't look this up, but Isaac Asimov
> mentioned that a friend had cataract surgery and could see shades of
> purple that others could only imagine. It was in the preface of one of
> his sci-fi books around 1960. He was not only a writer but a real
> professor, so I think that one would prove to be true. Finding a
> reference might be a bit rough, but the Opthalmology association should
> mention it somewhere.
> Super high frequency radio == infra-red.
> Super infra-red == ultra UHF radio.
> Simple?
> Bill Baka
If you ever opened the back of an old valve radio you would see that the
rectifier valves do indeed glow, and therefore are in the visible
spectrum of light, and they rectify, which makes them diodes, light
emitting diodes.
Friday
|
| | | | | | | | |
Date: 18 Jun 2007 01:22:23
From: Bill
Subject: Re: What is a Solid State Emmiter?
|
Friday wrote:
> Bill wrote:
>>
>>
>> Hey, guys....
>> Heat is infra-red. Extremely infra-red becomes ultra high frequency
>> radio waves. The different colors of LEDs are due to the band-gap
>> energies involved in the chemical cocktail used to make the LED.
>> Each blend puts out light in a very narrow, almost spike, wavelength.
>> Red is around 750nM and Blue near UV is around 400nM, or 0.4 microns.
>> The human eye (retina) can detect down to 300nM but the lens cuts out
>> the light up to about 400nM. I didn't look this up, but Isaac Asimov
>> mentioned that a friend had cataract surgery and could see shades of
>> purple that others could only imagine. It was in the preface of one of
>> his sci-fi books around 1960. He was not only a writer but a real
>> professor, so I think that one would prove to be true. Finding a
>> reference might be a bit rough, but the Opthalmology association
>> should mention it somewhere.
>> Super high frequency radio == infra-red.
>> Super infra-red == ultra UHF radio.
>> Simple?
>> Bill Baka
>
> If you ever opened the back of an old valve radio you would see that the
> rectifier valves do indeed glow, and therefore are in the visible
> spectrum of light, and they rectify, which makes them diodes, light
> emitting diodes.
>
> Friday
I collect old high end 'valve' radios, and as you said the tubes are
both. With the old radios like my prize Hammarlund I don't even need to
turn on the lights and can get news directly from other countries before
it gets watered down for broadcast in the 'free' United States.
Bill Baka
|
| | | | | | | | |
Date: 17 Jun 2007 20:54:10
From: Mike Lackey
Subject: Re: What is a Solid State Emmiter?
|
"Electron movement may be acclereated by the addition of energy. Heat is
one form of energy which can be conveniently used to speed up the electron.
For example, if the tempature of a metal is gradually raised, the electrons
in the metal gain velocity. When the metal becomes hot enough, some
electrons may acquire sufficent speed to break away from the surface of the
metal.".
RCA Receiving Tube manual, (c) 1975.
What you are seeing when you look at the valves of an old radio are the
"heaters" that heat metal surfaces, whicn in turn provide a flow of
electrons from plate to cathode. Actually, the flow is from cathode to
plate, but that is a different subject for a different time. It is this
flow of electrons which provide the "valve" effect, allowing the valve to
vary the plate voltage relative to the grid voltate. This "phenoma" can be
used to implement voltage amplification, or amplitude modulationn, or
frequency modulation, whatever cranks your tractor.
A rectifier tube follows the same laws of physics: it is not exempt. It
does not provide energy because it glows: rather, the glow heats a small
pice of metal, which in turn provides a flow of electrons (energy) necessary
to transform AC to DC. Without the glow, a rectifier tube cannot conduct
energy from one potential to another.
Inside each rectifier tube (inside each vacuum tube) is a "heater", nothing
more than a smaller version of the household electric heaters you can buy at
Lowe's or Wally World. The heater heats a small piece of metal, which in
turn causes a release of electrons from plate to cathode when the plate is
positively charged (relative to the cathode). The glow does not "provide"
the energy, it only "enables" the energy present on the metals to flow. In
a majoriy of circuits, "energy present" is nothing more than a AC voltage
provided by a transformer (when plate is positively charged relative to
cathode). A rectifier tube behaves very much like an LED, but it does not
glow because it is an LED, rather the glow enables it to behave like an LED.
The remainder of the tubes inside an old valve radio do not behave as LEDs.
They are not LEDs because they glow: nor does the glow indicate they are
LEDs. They are most commonely used as linear voltage amplifers (in triode
of pentode mode), or as frequency or voltage modulators, depending on the
application. Regardless, they glow because a heater inside a tube is
elevating the tempature of a piece of metal, which is in turn provides a
(controllable) flow of electrons. Once again, the glow does not imply they
are LEDs.
Mike Lackey
Madison, AL
Friday" <nowhere@sometime.net.au > wrote in message
news:4675265b_5@news.peopletelecom.com.au...
> Bill wrote:
>> jim beam wrote:
>>> Peter Cole wrote:
>>>> jim beam wrote:
>>>>
>>>>> actually, /all/ semicons emit light when they conduct, you just don't
>>>>> usually get to see it because of the casing. and it's usually in the
>>>>> infra-red spectrum.
>>>>
>>>> I'm afraid you're quite wrong.
>>>
>>> no, i'm quite right. re-read my post. "light" isn't just visible.
>>>
>>>>
>>>> http://en.wikipedia.org/wiki/Led :
>>>>
>>>> "The wavelength of the light emitted, and therefore its colour, depends
>>>> on the band gap energy of the materials forming the p-n junction. In
>>>> silicon or germanium diodes, the electrons and holes recombine by a
>>>> non-radiative transition which produces no optical
>>>
>>> note: OPTICAL.
>>>
>>>> emission, because these are indirect band gap materials. The materials
>>>> used for an LED have a direct band gap with energies corresponding to
>>>> near-infrared, visible or near-ultraviolet light."
>>>
>>> that's why i said infra-red. normal semiconductors emit in infra-red.
>>> with chemistry, you can tune the band gap to optical energies, and thus
>>> get visible emissions. but you don't do that for standard semicons!
>>> look up the band gap energies and correlate them to emission spectrum.
>>
>>
>> Hey, guys....
>> Heat is infra-red. Extremely infra-red becomes ultra high frequency radio
>> waves. The different colors of LEDs are due to the band-gap energies
>> involved in the chemical cocktail used to make the LED.
>> Each blend puts out light in a very narrow, almost spike, wavelength.
>> Red is around 750nM and Blue near UV is around 400nM, or 0.4 microns.
>> The human eye (retina) can detect down to 300nM but the lens cuts out the
>> light up to about 400nM. I didn't look this up, but Isaac Asimov
>> mentioned that a friend had cataract surgery and could see shades of
>> purple that others could only imagine. It was in the preface of one of
>> his sci-fi books around 1960. He was not only a writer but a real
>> professor, so I think that one would prove to be true. Finding a
>> reference might be a bit rough, but the Opthalmology association should
>> mention it somewhere.
>> Super high frequency radio == infra-red.
>> Super infra-red == ultra UHF radio.
>> Simple?
>> Bill Baka
>
> If you ever opened the back of an old valve radio you would see that the
> rectifier valves do indeed glow, and therefore are in the visible spectrum
> of light, and they rectify, which makes them diodes, light emitting
> diodes.
>
> Friday
|
| | | | | | | | | |
Date: 17 Jun 2007 21:52:58
From: R Brickston
Subject: Re: What is a Solid State Emmiter?
|
On Sun, 17 Jun 2007 20:54:10 GMT, "Mike Lackey"
<mr.blutarsky@mchsi.com > wrote:
>"Electron movement may be acclereated by the addition of energy. Heat is
>one form of energy which can be conveniently used to speed up the electron.
>For example, if the tempature of a metal is gradually raised, the electrons
>in the metal gain velocity. When the metal becomes hot enough, some
>electrons may acquire sufficent speed to break away from the surface of the
>metal.".
>
>RCA Receiving Tube manual, (c) 1975.
>
>What you are seeing when you look at the valves of an old radio are the
>"heaters" that heat metal surfaces, whicn in turn provide a flow of
>electrons from plate to cathode. Actually, the flow is from cathode to
>plate, but that is a different subject for a different time. It is this
>flow of electrons which provide the "valve" effect, allowing the valve to
>vary the plate voltage relative to the grid voltate. This "phenoma" can be
>used to implement voltage amplification, or amplitude modulationn, or
>frequency modulation, whatever cranks your tractor.
>
>A rectifier tube follows the same laws of physics: it is not exempt. It
>does not provide energy because it glows: rather, the glow heats a small
>pice of metal, which in turn provides a flow of electrons (energy) necessary
>to transform AC to DC. Without the glow, a rectifier tube cannot conduct
>energy from one potential to another.
>
>Inside each rectifier tube (inside each vacuum tube) is a "heater", nothing
>more than a smaller version of the household electric heaters you can buy at
>Lowe's or Wally World. The heater heats a small piece of metal, which in
>turn causes a release of electrons from plate to cathode when the plate is
>positively charged (relative to the cathode). The glow does not "provide"
>the energy, it only "enables" the energy present on the metals to flow. In
>a majoriy of circuits, "energy present" is nothing more than a AC voltage
>provided by a transformer (when plate is positively charged relative to
>cathode). A rectifier tube behaves very much like an LED, but it does not
>glow because it is an LED, rather the glow enables it to behave like an LED.
>
>The remainder of the tubes inside an old valve radio do not behave as LEDs.
>They are not LEDs because they glow: nor does the glow indicate they are
>LEDs. They are most commonely used as linear voltage amplifers (in triode
>of pentode mode), or as frequency or voltage modulators, depending on the
>application. Regardless, they glow because a heater inside a tube is
>elevating the tempature of a piece of metal, which is in turn provides a
>(controllable) flow of electrons. Once again, the glow does not imply they
>are LEDs.
>
>Mike Lackey
>Madison, AL
OR--Like I said earlier: They glow only because of voltage used to
produce the heat to make the thing work, the actual diode function is
independent of the current that produces the light emission.
|
| | | | | | | | |
Date: 17 Jun 2007 12:44:47
From: R Brickston
Subject: Re: What is a Solid State Emmiter?
|
On Sun, 17 Jun 2007 20:13:35 +0800, Friday <nowhere@sometime.net.au >
wrote:
>Bill wrote:
>> jim beam wrote:
>>> Peter Cole wrote:
>>>> jim beam wrote:
>>>>
>>>>> actually, /all/ semicons emit light when they conduct, you just
>>>>> don't usually get to see it because of the casing. and it's usually
>>>>> in the infra-red spectrum.
>>>>
>>>> I'm afraid you're quite wrong.
>>>
>>> no, i'm quite right. re-read my post. "light" isn't just visible.
>>>
>>>>
>>>> http://en.wikipedia.org/wiki/Led :
>>>>
>>>> "The wavelength of the light emitted, and therefore its colour,
>>>> depends on the band gap energy of the materials forming the p-n
>>>> junction. In silicon or germanium diodes, the electrons and holes
>>>> recombine by a non-radiative transition which produces no optical
>>>
>>> note: OPTICAL.
>>>
>>>> emission, because these are indirect band gap materials. The
>>>> materials used for an LED have a direct band gap with energies
>>>> corresponding to near-infrared, visible or near-ultraviolet light."
>>>
>>> that's why i said infra-red. normal semiconductors emit in infra-red.
>>> with chemistry, you can tune the band gap to optical energies, and
>>> thus get visible emissions. but you don't do that for standard
>>> semicons! look up the band gap energies and correlate them to emission
>>> spectrum.
>>
>>
>> Hey, guys....
>> Heat is infra-red. Extremely infra-red becomes ultra high frequency
>> radio waves. The different colors of LEDs are due to the band-gap
>> energies involved in the chemical cocktail used to make the LED.
>> Each blend puts out light in a very narrow, almost spike, wavelength.
>> Red is around 750nM and Blue near UV is around 400nM, or 0.4 microns.
>> The human eye (retina) can detect down to 300nM but the lens cuts out
>> the light up to about 400nM. I didn't look this up, but Isaac Asimov
>> mentioned that a friend had cataract surgery and could see shades of
>> purple that others could only imagine. It was in the preface of one of
>> his sci-fi books around 1960. He was not only a writer but a real
>> professor, so I think that one would prove to be true. Finding a
>> reference might be a bit rough, but the Opthalmology association should
>> mention it somewhere.
>> Super high frequency radio == infra-red.
>> Super infra-red == ultra UHF radio.
>> Simple?
>> Bill Baka
>
>If you ever opened the back of an old valve radio you would see that the
>rectifier valves do indeed glow, and therefore are in the visible
>spectrum of light, and they rectify, which makes them diodes, light
>emitting diodes.
>
>Friday
I think not. They glow only because of voltage used to produce the
heat to make the thing work, the actual diode function is independent
of the current that produces the light emission.
|
| | | | | | | | | |
Date: 17 Jun 2007 22:20:21
From: Friday
Subject: Re: What is a Solid State Emmiter?
|
R Brickston wrote:
> On Sun, 17 Jun 2007 20:13:35 +0800, Friday <nowhere@sometime.net.au>
> wrote:
>
>> Bill wrote:
>>> jim beam wrote:
>>>> Peter Cole wrote:
>>>>> jim beam wrote:
>>>>>
>>>>>> actually, /all/ semicons emit light when they conduct, you just
>>>>>> don't usually get to see it because of the casing. and it's usually
>>>>>> in the infra-red spectrum.
>>>>> I'm afraid you're quite wrong.
>>>> no, i'm quite right. re-read my post. "light" isn't just visible.
>>>>
>>>>> http://en.wikipedia.org/wiki/Led :
>>>>>
>>>>> "The wavelength of the light emitted, and therefore its colour,
>>>>> depends on the band gap energy of the materials forming the p-n
>>>>> junction. In silicon or germanium diodes, the electrons and holes
>>>>> recombine by a non-radiative transition which produces no optical
>>>> note: OPTICAL.
>>>>
>>>>> emission, because these are indirect band gap materials. The
>>>>> materials used for an LED have a direct band gap with energies
>>>>> corresponding to near-infrared, visible or near-ultraviolet light."
>>>> that's why i said infra-red. normal semiconductors emit in infra-red.
>>>> with chemistry, you can tune the band gap to optical energies, and
>>>> thus get visible emissions. but you don't do that for standard
>>>> semicons! look up the band gap energies and correlate them to emission
>>>> spectrum.
>>>
>>> Hey, guys....
>>> Heat is infra-red. Extremely infra-red becomes ultra high frequency
>>> radio waves. The different colors of LEDs are due to the band-gap
>>> energies involved in the chemical cocktail used to make the LED.
>>> Each blend puts out light in a very narrow, almost spike, wavelength.
>>> Red is around 750nM and Blue near UV is around 400nM, or 0.4 microns.
>>> The human eye (retina) can detect down to 300nM but the lens cuts out
>>> the light up to about 400nM. I didn't look this up, but Isaac Asimov
>>> mentioned that a friend had cataract surgery and could see shades of
>>> purple that others could only imagine. It was in the preface of one of
>>> his sci-fi books around 1960. He was not only a writer but a real
>>> professor, so I think that one would prove to be true. Finding a
>>> reference might be a bit rough, but the Opthalmology association should
>>> mention it somewhere.
>>> Super high frequency radio == infra-red.
>>> Super infra-red == ultra UHF radio.
>>> Simple?
>>> Bill Baka
>> If you ever opened the back of an old valve radio you would see that the
>> rectifier valves do indeed glow, and therefore are in the visible
>> spectrum of light, and they rectify, which makes them diodes, light
>> emitting diodes.
>>
>> Friday
>
> I think not. They glow only because of voltage used to produce the
> heat to make the thing work, the actual diode function is independent
> of the current that produces the light emission.
Does it glow or doesn't it?
|
| | | | | | | | | | |
Date: 17 Jun 2007 07:36:59
From: jim beam
Subject: Re: What is a Solid State Emmiter?
|
Friday wrote:
> R Brickston wrote:
>> On Sun, 17 Jun 2007 20:13:35 +0800, Friday <nowhere@sometime.net.au>
>> wrote:
>>
>>> Bill wrote:
>>>> jim beam wrote:
>>>>> Peter Cole wrote:
>>>>>> jim beam wrote:
>>>>>>
>>>>>>> actually, /all/ semicons emit light when they conduct, you just
>>>>>>> don't usually get to see it because of the casing. and it's
>>>>>>> usually in the infra-red spectrum.
>>>>>> I'm afraid you're quite wrong.
>>>>> no, i'm quite right. re-read my post. "light" isn't just visible.
>>>>>
>>>>>> http://en.wikipedia.org/wiki/Led :
>>>>>>
>>>>>> "The wavelength of the light emitted, and therefore its colour,
>>>>>> depends on the band gap energy of the materials forming the p-n
>>>>>> junction. In silicon or germanium diodes, the electrons and holes
>>>>>> recombine by a non-radiative transition which produces no optical
>>>>> note: OPTICAL.
>>>>>
>>>>>> emission, because these are indirect band gap materials. The
>>>>>> materials used for an LED have a direct band gap with energies
>>>>>> corresponding to near-infrared, visible or near-ultraviolet light."
>>>>> that's why i said infra-red. normal semiconductors emit in
>>>>> infra-red. with chemistry, you can tune the band gap to optical
>>>>> energies, and thus get visible emissions. but you don't do that
>>>>> for standard semicons! look up the band gap energies and correlate
>>>>> them to emission spectrum.
>>>>
>>>> Hey, guys....
>>>> Heat is infra-red. Extremely infra-red becomes ultra high frequency
>>>> radio waves. The different colors of LEDs are due to the band-gap
>>>> energies involved in the chemical cocktail used to make the LED.
>>>> Each blend puts out light in a very narrow, almost spike, wavelength.
>>>> Red is around 750nM and Blue near UV is around 400nM, or 0.4 microns.
>>>> The human eye (retina) can detect down to 300nM but the lens cuts
>>>> out the light up to about 400nM. I didn't look this up, but Isaac
>>>> Asimov mentioned that a friend had cataract surgery and could see
>>>> shades of purple that others could only imagine. It was in the
>>>> preface of one of his sci-fi books around 1960. He was not only a
>>>> writer but a real professor, so I think that one would prove to be
>>>> true. Finding a reference might be a bit rough, but the Opthalmology
>>>> association should mention it somewhere.
>>>> Super high frequency radio == infra-red.
>>>> Super infra-red == ultra UHF radio.
>>>> Simple?
>>>> Bill Baka
>>> If you ever opened the back of an old valve radio you would see that
>>> the rectifier valves do indeed glow, and therefore are in the visible
>>> spectrum of light, and they rectify, which makes them diodes, light
>>> emitting diodes.
>>>
>>> Friday
>>
>> I think not. They glow only because of voltage used to produce the
>> heat to make the thing work, the actual diode function is independent
>> of the current that produces the light emission.
>
> Does it glow or doesn't it?
it doesn't glow as part of the rectifier function!!! you're talking
ordinary incandescence.
|
| | | | | | | | | | | |
Date: 17 Jun 2007 23:15:30
From: Friday
Subject: Re: What is a Solid State Emmiter?
|
jim beam wrote:
> Friday wrote:
>> R Brickston wrote:
>>> On Sun, 17 Jun 2007 20:13:35 +0800, Friday <nowhere@sometime.net.au>
>>> wrote:
>>>
>>>> Bill wrote:
>>>>> jim beam wrote:
>>>>>> Peter Cole wrote:
>>>>>>> jim beam wrote:
>>>>>>>
>>>>>>>> actually, /all/ semicons emit light when they conduct, you just
>>>>>>>> don't usually get to see it because of the casing. and it's
>>>>>>>> usually in the infra-red spectrum.
>>>>>>> I'm afraid you're quite wrong.
>>>>>> no, i'm quite right. re-read my post. "light" isn't just visible.
>>>>>>
>>>>>>> http://en.wikipedia.org/wiki/Led :
>>>>>>>
>>>>>>> "The wavelength of the light emitted, and therefore its colour,
>>>>>>> depends on the band gap energy of the materials forming the p-n
>>>>>>> junction. In silicon or germanium diodes, the electrons and holes
>>>>>>> recombine by a non-radiative transition which produces no optical
>>>>>> note: OPTICAL.
>>>>>>
>>>>>>> emission, because these are indirect band gap materials. The
>>>>>>> materials used for an LED have a direct band gap with energies
>>>>>>> corresponding to near-infrared, visible or near-ultraviolet light."
>>>>>> that's why i said infra-red. normal semiconductors emit in
>>>>>> infra-red. with chemistry, you can tune the band gap to optical
>>>>>> energies, and thus get visible emissions. but you don't do that
>>>>>> for standard semicons! look up the band gap energies and correlate
>>>>>> them to emission spectrum.
>>>>>
>>>>> Hey, guys....
>>>>> Heat is infra-red. Extremely infra-red becomes ultra high frequency
>>>>> radio waves. The different colors of LEDs are due to the band-gap
>>>>> energies involved in the chemical cocktail used to make the LED.
>>>>> Each blend puts out light in a very narrow, almost spike, wavelength.
>>>>> Red is around 750nM and Blue near UV is around 400nM, or 0.4 microns.
>>>>> The human eye (retina) can detect down to 300nM but the lens cuts
>>>>> out the light up to about 400nM. I didn't look this up, but Isaac
>>>>> Asimov mentioned that a friend had cataract surgery and could see
>>>>> shades of purple that others could only imagine. It was in the
>>>>> preface of one of his sci-fi books around 1960. He was not only a
>>>>> writer but a real professor, so I think that one would prove to be
>>>>> true. Finding a reference might be a bit rough, but the
>>>>> Opthalmology association should mention it somewhere.
>>>>> Super high frequency radio == infra-red.
>>>>> Super infra-red == ultra UHF radio.
>>>>> Simple?
>>>>> Bill Baka
>>>> If you ever opened the back of an old valve radio you would see that
>>>> the rectifier valves do indeed glow, and therefore are in the
>>>> visible spectrum of light, and they rectify, which makes them
>>>> diodes, light emitting diodes.
>>>>
>>>> Friday
>>>
>>> I think not. They glow only because of voltage used to produce the
>>> heat to make the thing work, the actual diode function is independent
>>> of the current that produces the light emission.
>>
>> Does it glow or doesn't it?
>
> it doesn't glow as part of the rectifier function!!! you're talking
> ordinary incandescence.
Just say yes or no.
|
| | | | | | | | | | | | |
Date: 17 Jun 2007 08:26:15
From: jim beam
Subject: Re: What is a Solid State Emmiter?
|
Friday wrote:
> jim beam wrote:
>> Friday wrote:
>>> R Brickston wrote:
>>>> On Sun, 17 Jun 2007 20:13:35 +0800, Friday <nowhere@sometime.net.au>
>>>> wrote:
>>>>
>>>>> Bill wrote:
>>>>>> jim beam wrote:
>>>>>>> Peter Cole wrote:
>>>>>>>> jim beam wrote:
>>>>>>>>
>>>>>>>>> actually, /all/ semicons emit light when they conduct, you just
>>>>>>>>> don't usually get to see it because of the casing. and it's
>>>>>>>>> usually in the infra-red spectrum.
>>>>>>>> I'm afraid you're quite wrong.
>>>>>>> no, i'm quite right. re-read my post. "light" isn't just visible.
>>>>>>>
>>>>>>>> http://en.wikipedia.org/wiki/Led :
>>>>>>>>
>>>>>>>> "The wavelength of the light emitted, and therefore its colour,
>>>>>>>> depends on the band gap energy of the materials forming the p-n
>>>>>>>> junction. In silicon or germanium diodes, the electrons and
>>>>>>>> holes recombine by a non-radiative transition which produces no
>>>>>>>> optical
>>>>>>> note: OPTICAL.
>>>>>>>
>>>>>>>> emission, because these are indirect band gap materials. The
>>>>>>>> materials used for an LED have a direct band gap with energies
>>>>>>>> corresponding to near-infrared, visible or near-ultraviolet light."
>>>>>>> that's why i said infra-red. normal semiconductors emit in
>>>>>>> infra-red. with chemistry, you can tune the band gap to optical
>>>>>>> energies, and thus get visible emissions. but you don't do that
>>>>>>> for standard semicons! look up the band gap energies and
>>>>>>> correlate them to emission spectrum.
>>>>>>
>>>>>> Hey, guys....
>>>>>> Heat is infra-red. Extremely infra-red becomes ultra high
>>>>>> frequency radio waves. The different colors of LEDs are due to the
>>>>>> band-gap energies involved in the chemical cocktail used to make
>>>>>> the LED.
>>>>>> Each blend puts out light in a very narrow, almost spike, wavelength.
>>>>>> Red is around 750nM and Blue near UV is around 400nM, or 0.4 microns.
>>>>>> The human eye (retina) can detect down to 300nM but the lens cuts
>>>>>> out the light up to about 400nM. I didn't look this up, but Isaac
>>>>>> Asimov mentioned that a friend had cataract surgery and could see
>>>>>> shades of purple that others could only imagine. It was in the
>>>>>> preface of one of his sci-fi books around 1960. He was not only a
>>>>>> writer but a real professor, so I think that one would prove to be
>>>>>> true. Finding a reference might be a bit rough, but the
>>>>>> Opthalmology association should mention it somewhere.
>>>>>> Super high frequency radio == infra-red.
>>>>>> Super infra-red == ultra UHF radio.
>>>>>> Simple?
>>>>>> Bill Baka
>>>>> If you ever opened the back of an old valve radio you would see
>>>>> that the rectifier valves do indeed glow, and therefore are in the
>>>>> visible spectrum of light, and they rectify, which makes them
>>>>> diodes, light emitting diodes.
>>>>>
>>>>> Friday
>>>>
>>>> I think not. They glow only because of voltage used to produce the
>>>> heat to make the thing work, the actual diode function is independent
>>>> of the current that produces the light emission.
>>>
>>> Does it glow or doesn't it?
>>
>> it doesn't glow as part of the rectifier function!!! you're talking
>> ordinary incandescence.
>
> Just say yes or no.
incandescence is not rectification!!! do you understand physics? yes
or no.
|
| | | | | | | | | | | | | |
Date: 18 Jun 2007 01:24:42
From: Bill
Subject: Re: What is a Solid State Emmiter?
|
jim beam wrote:
> Friday wrote:
>>
>> Just say yes or no.
>
> incandescence is not rectification!!! do you understand physics? yes
> or no.
Some guys will argue with a rock and lose.
These meaningless arguments are fun to watch, though.
Bill Baka
|
| | | | | | | | | | | | | | |
Date: 18 Jun 2007 06:14:04
From: jim beam
Subject: Re: What is a Solid State Emmiter?
|
Bill wrote:
> jim beam wrote:
>> Friday wrote:
>>>
>>> Just say yes or no.
>>
>> incandescence is not rectification!!! do you understand physics? yes
>> or no.
>
> Some guys will argue with a rock and lose.
> These meaningless arguments are fun to watch, though.
> Bill Baka
incandescence is /still/ not rectification bill.
|
| | | | | | | | | | | | | | | |
Date: 18 Jun 2007 13:29:22
From: Bill
Subject: Re: What is a Solid State Emmiter?
|
jim beam wrote:
> Bill wrote:
>> jim beam wrote:
>>> Friday wrote:
>>>>
>>>> Just say yes or no.
>>>
>>> incandescence is not rectification!!! do you understand physics?
>>> yes or no.
>>
>> Some guys will argue with a rock and lose.
>> These meaningless arguments are fun to watch, though.
>> Bill Baka
>
> incandescence is /still/ not rectification bill.
Why bother? Incandescence is just light emitted from a variable resistor
filament. The low resistance at turn on is what makes the weakest point
go Supernova when you turn on a bulb that is ready to go out with a
bang, err, flash.
IF the bulb was a vacuum and IF there was a plate (anode) you could call
it a very bright rectifier, but then you would have only a very
primitive tube with no indirectly heated cathode.
Bill Baka
|
| | | | | | | | | | | | | | | | |
Date: 18 Jun 2007 19:35:36
From: jim beam
Subject: Re: What is a Solid State Emmiter?
|
Bill wrote:
> jim beam wrote:
>> Bill wrote:
>>> jim beam wrote:
>>>> Friday wrote:
>>>>>
>>>>> Just say yes or no.
>>>>
>>>> incandescence is not rectification!!! do you understand physics?
>>>> yes or no.
>>>
>>> Some guys will argue with a rock and lose.
>>> These meaningless arguments are fun to watch, though.
>>> Bill Baka
>>
>> incandescence is /still/ not rectification bill.
>
> Why bother? Incandescence is just light emitted from a variable resistor
> filament. The low resistance at turn on is what makes the weakest point
> go Supernova when you turn on a bulb that is ready to go out with a
> bang, err, flash.
> IF the bulb was a vacuum and IF there was a plate (anode) you could call
> it a very bright rectifier, but then you would have only a very
> primitive tube with no indirectly heated cathode.
> Bill Baka
but there's still no similarity in physics bill. just like fission and
combustion both produce heat, but their physics are totally different.
|
| | | | | | | | | | | | | | | | | |
Date: 19 Jun 2007 03:13:01
From: Bill
Subject: Re: What is a Solid State Emmiter?
|
jim beam wrote:
> Bill wrote:
>> Why bother? Incandescence is just light emitted from a variable
>> resistor filament. The low resistance at turn on is what makes the
>> weakest point go Supernova when you turn on a bulb that is ready to go
>> out with a bang, err, flash.
>> IF the bulb was a vacuum and IF there was a plate (anode) you could
>> call it a very bright rectifier, but then you would have only a very
>> primitive tube with no indirectly heated cathode.
>> Bill Baka
>
> but there's still no similarity in physics bill. just like fission and
> combustion both produce heat, but their physics are totally different.
I know that, so I think I got mis-quoted somewhere along the line or at
least mis-understood. This is bicycle tech, not physics tech, so why go
all hyper scientific? At least I didn't say "Thermionic valve".
LEDs have electrons jumping all over the place to make light while
conducting electricity and their chemical makeup influences the actual
wavelength of the light emitted, but there are so many varieties that I
would actually have to read up on it again. The one thing that does seem
to be constant is that some LEDs produce 600 nm exactly, while another
will produce 604 nm exactly, regardless of current, just bright or dim.
That is physics. Incandescence is dependent on temperature so hotter
equals shorter wavelengths. This explains why Quartz-Halogens that burn
so hot look bluer than normal headlights.
I get it, but don't want to make a big deal on the bicycle groups.
Bill Baka
|
| | | | | | | | | | | | | | | | | | |
Date: 18 Jun 2007 20:24:05
From: jim beam
Subject: Re: What is a Solid State Emmiter?
|
Bill wrote:
> jim beam wrote:
>> Bill wrote:
>>> Why bother? Incandescence is just light emitted from a variable
>>> resistor filament. The low resistance at turn on is what makes the
>>> weakest point go Supernova when you turn on a bulb that is ready to
>>> go out with a bang, err, flash.
>>> IF the bulb was a vacuum and IF there was a plate (anode) you could
>>> call it a very bright rectifier, but then you would have only a very
>>> primitive tube with no indirectly heated cathode.
>>> Bill Baka
>>
>> but there's still no similarity in physics bill. just like fission
>> and combustion both produce heat, but their physics are totally
>> different.
>
> I know that, so I think I got mis-quoted somewhere along the line or at
> least mis-understood. This is bicycle tech, not physics tech, so why go
> all hyper scientific? At least I didn't say "Thermionic valve".
> LEDs have electrons jumping all over the place to make light while
> conducting electricity and their chemical makeup influences the actual
> wavelength of the light emitted, but there are so many varieties that I
> would actually have to read up on it again. The one thing that does seem
> to be constant is that some LEDs produce 600 nm exactly, while another
> will produce 604 nm exactly, regardless of current, just bright or dim.
> That is physics. Incandescence is dependent on temperature so hotter
> equals shorter wavelengths. This explains why Quartz-Halogens that burn
> so hot look bluer than normal headlights.
> I get it, but don't want to make a big deal on the bicycle groups.
> Bill Baka
you don't get it because you were trying to equate incandescence with
what is essentially laser behavior. trying to fudge by saying that
because it's only bike tech, it's not going to get a proper explanation
is disgraceful.
|
| | | | | | | | | | | | | | | | | | | |
Date: 18 Jun 2007 20:38:10
From: Bill
Subject: Re: What is a Solid State Emmiter?
|
jim beam wrote:
> Bill wrote:
>> jim beam wrote:
>>> Bill wrote:
>>>> Why bother? Incandescence is just light emitted from a variable
>>>> resistor filament. The low resistance at turn on is what makes the
>>>> weakest point go Supernova when you turn on a bulb that is ready to
>>>> go out with a bang, err, flash.
>>>> IF the bulb was a vacuum and IF there was a plate (anode) you could
>>>> call it a very bright rectifier, but then you would have only a very
>>>> primitive tube with no indirectly heated cathode.
>>>> Bill Baka
>>>
>>> but there's still no similarity in physics bill. just like fission
>>> and combustion both produce heat, but their physics are totally
>>> different.
>>
>> I know that, so I think I got mis-quoted somewhere along the line or
>> at least mis-understood. This is bicycle tech, not physics tech, so
>> why go all hyper scientific? At least I didn't say "Thermionic valve".
>> LEDs have electrons jumping all over the place to make light while
>> conducting electricity and their chemical makeup influences the actual
>> wavelength of the light emitted, but there are so many varieties that
>> I would actually have to read up on it again. The one thing that does
>> seem to be constant is that some LEDs produce 600 nm exactly, while
>> another will produce 604 nm exactly, regardless of current, just
>> bright or dim.
>> That is physics. Incandescence is dependent on temperature so hotter
>> equals shorter wavelengths. This explains why Quartz-Halogens that
>> burn so hot look bluer than normal headlights.
>> I get it, but don't want to make a big deal on the bicycle groups.
>> Bill Baka
>
> you don't get it because you were trying to equate incandescence with
> what is essentially laser behavior. trying to fudge by saying that
> because it's only bike tech, it's not going to get a proper explanation
> is disgraceful.
I got it the first time. I am not always totally stick up my ass
serious. Fission and fusion both produce heat and light, but by
different means. Am I going there?
Hell no.
I'm going to watch the boob tube now.
Bill Baka
|
| | | | | | | | | | | | | | | | | | | | |
Date: 19 Jun 2007 13:02:29
From: RBrickston
Subject: Re: What is a Solid State Emmiter?
|
In article <LcIdi.2110$vi5.1530@newssvr17.news.prodigy.net >,
bbaka@comcast.net says...
> jim beam wrote:
> > Bill wrote:
> >> jim beam wrote:
> >>> Bill wrote:
> >>>> Why bother? Incandescence is just light emitted from a variable
> >>>> resistor filament. The low resistance at turn on is what makes the
> >>>> weakest point go Supernova when you turn on a bulb that is ready to
> >>>> go out with a bang, err, flash.
> >>>> IF the bulb was a vacuum and IF there was a plate (anode) you could
> >>>> call it a very bright rectifier, but then you would have only a very
> >>>> primitive tube with no indirectly heated cathode.
> >>>> Bill Baka
> >>>
> >>> but there's still no similarity in physics bill. just like fission
> >>> and combustion both produce heat, but their physics are totally
> >>> different.
> >>
> >> I know that, so I think I got mis-quoted somewhere along the line or
> >> at least mis-understood. This is bicycle tech, not physics tech, so
> >> why go all hyper scientific? At least I didn't say "Thermionic valve".
> >> LEDs have electrons jumping all over the place to make light while
> >> conducting electricity and their chemical makeup influences the actual
> >> wavelength of the light emitted, but there are so many varieties that
> >> I would actually have to read up on it again. The one thing that does
> >> seem to be constant is that some LEDs produce 600 nm exactly, while
> >> another will produce 604 nm exactly, regardless of current, just
> >> bright or dim.
> >> That is physics. Incandescence is dependent on temperature so hotter
> >> equals shorter wavelengths. This explains why Quartz-Halogens that
> >> burn so hot look bluer than normal headlights.
> >> I get it, but don't want to make a big deal on the bicycle groups.
> >> Bill Baka
> >
> > you don't get it because you were trying to equate incandescence with
> > what is essentially laser behavior. trying to fudge by saying that
> > because it's only bike tech, it's not going to get a proper explanation
> > is disgraceful.
>
> I got it the first time. I am not always totally stick up my ass
> serious. Fission and fusion both produce heat and light, but by
> different means. Am I going there?
> Hell no.
> I'm going to watch the boob tube now.
> Bill Baka
Boob tube, with yourself as the star.
|
| | | | | | | | | |
Date: 17 Jun 2007 07:06:25
From: jim beam
Subject: Re: What is a Solid State Emmiter?
|
R Brickston wrote:
> On Sun, 17 Jun 2007 20:13:35 +0800, Friday <nowhere@sometime.net.au>
> wrote:
>
>> Bill wrote:
>>> jim beam wrote:
>>>> Peter Cole wrote:
>>>>> jim beam wrote:
>>>>>
>>>>>> actually, /all/ semicons emit light when they conduct, you just
>>>>>> don't usually get to see it because of the casing. and it's usually
>>>>>> in the infra-red spectrum.
>>>>> I'm afraid you're quite wrong.
>>>> no, i'm quite right. re-read my post. "light" isn't just visible.
>>>>
>>>>> http://en.wikipedia.org/wiki/Led :
>>>>>
>>>>> "The wavelength of the light emitted, and therefore its colour,
>>>>> depends on the band gap energy of the materials forming the p-n
>>>>> junction. In silicon or germanium diodes, the electrons and holes
>>>>> recombine by a non-radiative transition which produces no optical
>>>> note: OPTICAL.
>>>>
>>>>> emission, because these are indirect band gap materials. The
>>>>> materials used for an LED have a direct band gap with energies
>>>>> corresponding to near-infrared, visible or near-ultraviolet light."
>>>> that's why i said infra-red. normal semiconductors emit in infra-red.
>>>> with chemistry, you can tune the band gap to optical energies, and
>>>> thus get visible emissions. but you don't do that for standard
>>>> semicons! look up the band gap energies and correlate them to emission
>>>> spectrum.
>>>
>>> Hey, guys....
>>> Heat is infra-red. Extremely infra-red becomes ultra high frequency
>>> radio waves. The different colors of LEDs are due to the band-gap
>>> energies involved in the chemical cocktail used to make the LED.
>>> Each blend puts out light in a very narrow, almost spike, wavelength.
>>> Red is around 750nM and Blue near UV is around 400nM, or 0.4 microns.
>>> The human eye (retina) can detect down to 300nM but the lens cuts out
>>> the light up to about 400nM. I didn't look this up, but Isaac Asimov
>>> mentioned that a friend had cataract surgery and could see shades of
>>> purple that others could only imagine. It was in the preface of one of
>>> his sci-fi books around 1960. He was not only a writer but a real
>>> professor, so I think that one would prove to be true. Finding a
>>> reference might be a bit rough, but the Opthalmology association should
>>> mention it somewhere.
>>> Super high frequency radio == infra-red.
>>> Super infra-red == ultra UHF radio.
>>> Simple?
>>> Bill Baka
>> If you ever opened the back of an old valve radio you would see that the
>> rectifier valves do indeed glow, and therefore are in the visible
>> spectrum of light, and they rectify, which makes them diodes, light
>> emitting diodes.
>>
>> Friday
>
> I think not. They glow only because of voltage used to produce the
> heat to make the thing work, the actual diode function is independent
> of the current that produces the light emission.
indeed.
|
| | | | | | | |
Date: 17 Jun 2007 11:49:43
From: R Brickston
Subject: Re: What is a Solid State Emmiter?
|
On Sat, 16 Jun 2007 21:47:20 -0700, Bill <bbaka@comcast.net > wrote:
>jim beam wrote:
>> Peter Cole wrote:
>>> jim beam wrote:
>>>
>>>> actually, /all/ semicons emit light when they conduct, you just don't
>>>> usually get to see it because of the casing. and it's usually in the
>>>> infra-red spectrum.
>>>
>>> I'm afraid you're quite wrong.
>>
>> no, i'm quite right. re-read my post. "light" isn't just visible.
>>
>>>
>>> http://en.wikipedia.org/wiki/Led :
>>>
>>> "The wavelength of the light emitted, and therefore its colour,
>>> depends on the band gap energy of the materials forming the p-n
>>> junction. In silicon or germanium diodes, the electrons and holes
>>> recombine by a non-radiative transition which produces no optical
>>
>> note: OPTICAL.
>>
>>> emission, because these are indirect band gap materials. The materials
>>> used for an LED have a direct band gap with energies corresponding to
>>> near-infrared, visible or near-ultraviolet light."
>>
>> that's why i said infra-red. normal semiconductors emit in infra-red.
>> with chemistry, you can tune the band gap to optical energies, and thus
>> get visible emissions. but you don't do that for standard semicons!
>> look up the band gap energies and correlate them to emission spectrum.
>
>
>Hey, guys....
>Heat is infra-red. Extremely infra-red becomes ultra high frequency
>radio waves. The different colors of LEDs are due to the band-gap
>energies involved in the chemical cocktail used to make the LED.
>Each blend puts out light in a very narrow, almost spike, wavelength.
>Red is around 750nM and Blue near UV is around 400nM, or 0.4 microns.
>The human eye (retina) can detect down to 300nM but the lens cuts out
>the light up to about 400nM. I didn't look this up, but Isaac Asimov
>mentioned that a friend had cataract surgery and could see shades of
>purple that others could only imagine. It was in the preface of one of
>his sci-fi books around 1960. He was not only a writer but a real
>professor, so I think that one would prove to be true. Finding a
>reference might be a bit rough, but the Opthalmology association should
>mention it somewhere.
>Super high frequency radio == infra-red.
>Super infra-red == ultra UHF radio.
>Simple?
>Bill Baka
Billy can regurgitate without knowledge, obviously.
|
| | |
Date: 16 Jun 2007 02:22:41
From: Bill
Subject: Re: What is a Solid State Emmiter?
|
Mike Lackey wrote:
> It's hard to know for sure, because no technical specs are given. But my
> first impression is some marketing bozo is looking for a way to distinguish
> his product from other LED lights by using the term "emitter" instad of
> "light emitting diode". IMHO, more "buycycling" hype.
>
> However, Luxeon was one of the fist to successfully market high-intensity
> LED's, many of their products were designed to conveniently replace
> flashlight bulbs. Google for Luxeon and it should become apparent. Perhaps
> a "Super Lux" is some marketing bozo's attempt way of saying it's a
> Luxeon-style LED.
>
> One thing for sure, LED lights will only get better in the future, as
> high-intensity technology (and optics) continue to both improve and come
> down in price.
>
> Mike Lackey
> Madison, AL
>
>
> <aburdette@gmail.com> wrote in message
> news:1181925205.403818.64560@p77g2000hsh.googlegroups.com...
>> Does anyone know what a solid state emitter is? Is it an LED? Is it
>> like an LED?
>>
>> http://www.vetta.com/Product_Lights_nMini.htm
>>
>> Thanks,
>>
>> alan.
>>
>
>
I found one bike site that was selling 3 watt single LED lights. Too bad
the top 2 were proprietary batteries, but there were 3 or 4 more that
used AA's, and NiMH rechargeable are not that hard to find. I use a
Cat-Eye with 5 LEDs and 4 AA rechargeable batteries. The NiMH only put
out about 1.2 volts and the Alkaline 1.5 volts so there will be a light
output issue, but my Cat-Eye is bright enough unless you want to be a
fast night rider, something I have learned not to do in the country or
on bad roads.
Bill Baka
|
| |
Date: 15 Jun 2007 09:52:13
From:
Subject: Re: What is a Solid State Emmiter?
|
On Jun 15, 11:46 am, Victor Kan <victor....@gmail.com > wrote:
> On Jun 15, 12:33 pm, aburde...@gmail.com wrote:
>
> > Does anyone know what a solid state emitter is? Is it an LED? Is it
> > like an LED?
>
> >http://www.vetta.com/Product_Lights_nMini.htm
>
> Yep, it's an LED.
>
> Maybe the term "solid state emitter" harkens back to the days when
> transistor based electronics came on the market and where brands
> wanted you to know your TV or whatever was "solid state" and turned on
> right away rather than having to warm up.
>
> Maybe with bike lights, they're playing up the solid state for
> durability against vibration and impacts, as well as not having to
> "warm up" (as HID lights do).
Thanks guys!
|
| |
Date: 15 Jun 2007 16:46:39
From: Victor Kan
Subject: Re: What is a Solid State Emmiter?
|
On Jun 15, 12:33 pm, aburde...@gmail.com wrote:
> Does anyone know what a solid state emitter is? Is it an LED? Is it
> like an LED?
>
> http://www.vetta.com/Product_Lights_nMini.htm
Yep, it's an LED.
Maybe the term "solid state emitter" harkens back to the days when
transistor based electronics came on the market and where brands
wanted you to know your TV or whatever was "solid state" and turned on
right away rather than having to warm up.
Maybe with bike lights, they're playing up the solid state for
durability against vibration and impacts, as well as not having to
"warm up" (as HID lights do).
|
| |
Date: 15 Jun 2007 17:43:09
From: Ben Micklem
Subject: Re: What is a Solid State Emmiter?
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in article 1181925205.403818.64560@p77g2000hsh.googlegroups.com,
aburdette@gmail.com at aburdette@gmail.com wrote on 15/6/07 17:33:
> Does anyone know what a solid state emitter is? Is it an LED?
Yes.
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