Comment on lightbulbs
Fedizen@lemmy.world 2 days agoThe 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.
Aceticon@lemmy.dbzer0.com 2 days ago
That’s not even close to reality.
Read the material linked.
Fedizen@lemmy.world 2 days ago
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.
Aceticon@lemmy.dbzer0.com 1 day ago
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 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 sence 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, which only emits photons whose energy exactly matches a specific quantum gap in that junction, hence all have the exact same wavelength so there are no other wavelengths to filter out and if you filter out that specific wavelength no light at all goes through 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 “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.
Fedizen@lemmy.world 12 hours ago
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 was dependent on that transparency.
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.