Huh, my bad, I thought thermal sources (ie. like random hot stuff, not glowing hot stuff) emitted a wide band of frequencies including near-IR, but fair enough. You'd still get it from any sort of incandescent light source right? (same as a sodium lamp)
> but with important advantages
What's the benefit over using any other single frequency visible light?
Even if the atmosphere absorbs most of a particular band, if any of it gets through, your mask is going to be messy, which kind of ruins the point; I don't know anything can really fix that for outdoor purposes?
I mean, broadly speaking, all you need is a way to emit a sharp frequency band and avoid having any environmental pollution in the same band.
If there's a good way to do that in near-IR, it would work; but I feel like the same could be said about pretty much any frequency.
I'm not aware of anything specific about near-IR that makes it particularly attractive.
(but, clearly, I'm no expert in near-IR)
> but with important advantages
What's the benefit over using any other single frequency visible light?
Even if the atmosphere absorbs most of a particular band, if any of it gets through, your mask is going to be messy, which kind of ruins the point; I don't know anything can really fix that for outdoor purposes?
I mean, broadly speaking, all you need is a way to emit a sharp frequency band and avoid having any environmental pollution in the same band.
If there's a good way to do that in near-IR, it would work; but I feel like the same could be said about pretty much any frequency.
I'm not aware of anything specific about near-IR that makes it particularly attractive.
(but, clearly, I'm no expert in near-IR)