LEDs aren’t just more efficient at those voltages, those are literally the difference in voltage between one side of the LED and the other side when in operation - if you feed it less than that the LED will simply not work. (Note that these drop voltages are not actually an absolute value but rather a very steep curve relative to current, but for simplification we can treat those as absolute ON/OFF voltage values).
Also the phosphor doesn’t filter light - rather it absorbs light and re-emits it in different wavelengths, the process being such that the emitted light covers a range of wavelengths even if the input light has a single wavelength as is the case for LEDs - so it’s not at all light manipulation by filtering and mixing light sources.
That said I went looking at how phosphor is used in LEDs nowadays and judging from this they don’t use red LEDs emitters at all nowadays, only blue and UV ones, and then chose a phosphor (which can be any substance, not just Phosphorous) whose emission range is towards the desired light range.
The phosphorous coating here is serving to reduce the amount of blue light as an absorptive filter. Its just also doing other stuff. Idk if there’s a proper term for what its doing in whole, but your explanation is otherwise in line with what I’ve read.
your explanation is otherwise in line with what I’ve read.
That’s not even close to reality
That’s a bit incoherent.
Fwiw, I did read the article you linked. That’s one of the articles I looked at originally.
I’m just saying its innapropriate to say its “not a filter” because the coating is doing more than partially filtering a wavelength of light; Its a categorical error.
The coating’s primary engineering function is not a filter, so maybe its frustrating to hear it described as one but it is absolutely incorrect to say its not a filter because one of things its literally doing is filtering out a % of the blue light emitted by the diode.
A phospor absorbs the incoming light and then uses it as power for its own emission process, in a processes called “fluorescence” rather than “filtering”. It’s a very efficient process because almost all of the light coming in and absorbed by the fluorescent material ends up used to emit light.
A filter just cuts out (literally “filters out”) things other than what it’s supposed to let through. Filters just block stuff and thus cannot have on their output anything that’s not present on their input. Further, filtering can be very inefficient because everything that the filter doesn’t let through just ends up as waste heat.
Filtering doesn’t make any sense for light emitted by a diode junction because that specific light emission process emits light of a single wavelength - it’s a totally different process from incandescence and only emits photons whose energy exactly matches a specific quantum gap in that junction, hence all emitted photons have the exact same wavelength, thus there are no other wavelengths in the light emitted by the diode to filter out - thus if you filter out that specific wavelength, no light at all goes through the filter because there’s nothing else there.
Calling a phospor a “filter” is like calling a system with a solar panel connected to a green LED a “filter” - sure, the spectrum of the light coming in is not the same as that of the light going out, but that’s pretty much the only way the thing behaves the same as a filter - it does not share any of the other characteristics of a filter.
Anybody with a Physics or Engineering background will react the same as me when somebody describes a fluorescent material in front of a light source as “a filter” because per the scientific and engineering definitions “fluorescence” is not at all the same as “filtering”.
Whatever source you learned information about LED lights from, it’s really bad and shows no domain expertise, which is probably why you ended up with some things right in your explanations and others horribly wrong. If I was to guess, I would say that you “learned” it from AI, as getting the general stuff mostly right and the domain expertise details incredibly wrong is a common problem of AI.
I was looking at exactly the same pages you were. Try reading those articles (or use ctrl+f) if you want to know where the filter discription is from.
You don’t need to concoct a fictional story about where the information came from. Its clear your purpose here isn’t to inform anyone at this point. If you’ve ever talked to an engineer prior to this you would not have this opinion of my colleages.
And the analogy here is so bad. If the solar panel were partially transparent and part of system (the resulting spectra) was dependent on that transparency it would work.
Engineers say its “acting as a filter” because thats a way of analyzing the system. For all and intents and purposes anything can effectively be modeled as a filter in certain design situations has been called a filter. So yes, engineers do talk like this.
Source: used to work in an electronics hardware development lab with electrical, optical, and software engineers.
Mate, I have a Masters in Electronics Engineering and a partial degree in Physics.
I just didn’t want to pull the authoritativeness card out, so instead tried to explain things to you from basic principles.
You’re either confusing some other application with what I was talking about - which was the emitters used in LED light bulbs, the ones which look yellow when they’re switched off, the yellow stuff being the phospor - or you mentally over-generalized something you heard, either to an area were it doesn’t apply or missing the required context to make sense.
You keep throwing conjectures out there based on somewhat head scratching assumptions. And you’re doing it again. I am not an electrical engineer, but I have worked in the industry long enough to know the electronic definition of filter is not the optical definition and often optical engineers do model things as filters for ease. I write engineering reports for a living. I do the english part of the engineering because they’re usually pretty bad at it.
When I said that I am in agreement with everything you said except referring to the phospher as “not a filter” I was fully aware of what the coating was doing. I concurred with that. And you said it was nowhere close to reality. Which is truly incoherent.
What I’m saying you’re muddying things by saying its not a filter. This is the sort of thing the electrical and optical engineers would say during meetings and the project managers would get annoyed because they’d both be talking past each other.
So like knowing you’re an electrical engineer here isn’t surprising. Engineers (and especially electrical engineers in my experience, probably the lead exposure) in general are abysmally bad writers, poor communicators and often overstate their disagreements by being unaware of their audience. Its why I’m called in to clean up their messes.
Here are the LED drop voltages for reference.
LEDs aren’t just more efficient at those voltages, those are literally the difference in voltage between one side of the LED and the other side when in operation - if you feed it less than that the LED will simply not work. (Note that these drop voltages are not actually an absolute value but rather a very steep curve relative to current, but for simplification we can treat those as absolute ON/OFF voltage values).
Also the phosphor doesn’t filter light - rather it absorbs light and re-emits it in different wavelengths, the process being such that the emitted light covers a range of wavelengths even if the input light has a single wavelength as is the case for LEDs - so it’s not at all light manipulation by filtering and mixing light sources.
That said I went looking at how phosphor is used in LEDs nowadays and judging from this they don’t use red LEDs emitters at all nowadays, only blue and UV ones, and then chose a phosphor (which can be any substance, not just Phosphorous) whose emission range is towards the desired light range.
I’ve corrected my original post.
The phosphorous coating here is serving to reduce the amount of blue light as an absorptive filter. Its just also doing other stuff. Idk if there’s a proper term for what its doing in whole, but your explanation is otherwise in line with what I’ve read.
That’s not even close to reality.
Read the material linked or just google it yourself.
That’s a bit incoherent.
Fwiw, I did read the article you linked. That’s one of the articles I looked at originally.
I’m just saying its innapropriate to say its “not a filter” because the coating is doing more than partially filtering a wavelength of light; Its a categorical error.
The coating’s primary engineering function is not a filter, so maybe its frustrating to hear it described as one but it is absolutely incorrect to say its not a filter because one of things its literally doing is filtering out a % of the blue light emitted by the diode.
A phospor absorbs the incoming light and then uses it as power for its own emission process, in a processes called “fluorescence” rather than “filtering”. It’s a very efficient process because almost all of the light coming in and absorbed by the fluorescent material ends up used to emit light.
A filter just cuts out (literally “filters out”) things other than what it’s supposed to let through. Filters just block stuff and thus cannot have on their output anything that’s not present on their input. Further, filtering can be very inefficient because everything that the filter doesn’t let through just ends up as waste heat.
Filtering doesn’t make any sense for light emitted by a diode junction because that specific light emission process emits light of a single wavelength - it’s a totally different process from incandescence and only emits photons whose energy exactly matches a specific quantum gap in that junction, hence all emitted photons have the exact same wavelength, thus there are no other wavelengths in the light emitted by the diode to filter out - thus if you filter out that specific wavelength, no light at all goes through the filter because there’s nothing else there.
Calling a phospor a “filter” is like calling a system with a solar panel connected to a green LED a “filter” - sure, the spectrum of the light coming in is not the same as that of the light going out, but that’s pretty much the only way the thing behaves the same as a filter - it does not share any of the other characteristics of a filter.
Anybody with a Physics or Engineering background will react the same as me when somebody describes a fluorescent material in front of a light source as “a filter” because per the scientific and engineering definitions “fluorescence” is not at all the same as “filtering”.
Whatever source you learned information about LED lights from, it’s really bad and shows no domain expertise, which is probably why you ended up with some things right in your explanations and others horribly wrong. If I was to guess, I would say that you “learned” it from AI, as getting the general stuff mostly right and the domain expertise details incredibly wrong is a common problem of AI.
I was looking at exactly the same pages you were. Try reading those articles (or use ctrl+f) if you want to know where the filter discription is from.
You don’t need to concoct a fictional story about where the information came from. Its clear your purpose here isn’t to inform anyone at this point. If you’ve ever talked to an engineer prior to this you would not have this opinion of my colleages.
And the analogy here is so bad. If the solar panel were partially transparent and part of system (the resulting spectra) was dependent on that transparency it would work.
Engineers say its “acting as a filter” because thats a way of analyzing the system. For all and intents and purposes anything can effectively be modeled as a filter in certain design situations has been called a filter. So yes, engineers do talk like this.
Source: used to work in an electronics hardware development lab with electrical, optical, and software engineers.
Mate, I have a Masters in Electronics Engineering and a partial degree in Physics.
I just didn’t want to pull the authoritativeness card out, so instead tried to explain things to you from basic principles.
You’re either confusing some other application with what I was talking about - which was the emitters used in LED light bulbs, the ones which look yellow when they’re switched off, the yellow stuff being the phospor - or you mentally over-generalized something you heard, either to an area were it doesn’t apply or missing the required context to make sense.
You keep throwing conjectures out there based on somewhat head scratching assumptions. And you’re doing it again. I am not an electrical engineer, but I have worked in the industry long enough to know the electronic definition of filter is not the optical definition and often optical engineers do model things as filters for ease. I write engineering reports for a living. I do the english part of the engineering because they’re usually pretty bad at it.
When I said that I am in agreement with everything you said except referring to the phospher as “not a filter” I was fully aware of what the coating was doing. I concurred with that. And you said it was nowhere close to reality. Which is truly incoherent.
What I’m saying you’re muddying things by saying its not a filter. This is the sort of thing the electrical and optical engineers would say during meetings and the project managers would get annoyed because they’d both be talking past each other.
So like knowing you’re an electrical engineer here isn’t surprising. Engineers (and especially electrical engineers in my experience, probably the lead exposure) in general are abysmally bad writers, poor communicators and often overstate their disagreements by being unaware of their audience. Its why I’m called in to clean up their messes.