So, is this something that can actually make infrared light visible, or a coating that can be applied directly to sensors? (I suspect the headline is simply clickbait/a lie, just like most university press releases.)
Colour-changing magnifying glass gives clear view of infrared light
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Re: Colour-changing magnifying glass gives clear view of infrared light
#12This will almost certainly be used for weapons in short order. Currently if you want thermal imaging or very low light capability you have to use very expensive substrates. Being able to use CMOS detectors for MWIR/LWIR would instantly increase available resolutions by an order of magnitude at any given price point, assuming these filters are actually relatively cheap.
Yep, if it works at all, ITAR will slap it with a "Don't even think about using this for anything" label.
Re: Colour-changing magnifying glass gives clear view of infrared light
#13So, is this something that can actually make infrared light visible, or a coating that can be applied directly to sensors? (I suspect the headline is simply clickbait/a lie, just like most university press releases.)
Not unimaginable, a similar coating is on the inside of fluorescent lighting tubes.
The phosphor coating of fluorescent tubes downconverts UV light into visible wavelengths (is, lower energy/frequency) through the process of fluorescence. The UV photons excite the electrons of the phosphor molecules to higher energy states, after which they emit photons at lower frequencies/energies (visible light) as they fluoresce back to the ground state.
In this case however, the IR to visible light conversion actually increases the energy and frequency of emitted photons.
Total energy must be conserved, so extra energy is incorporated in some way for the upconversion.
There was a plastic film material I saw a few decades ago that lights up when you shine infrared light on it, which was useful for testing IR transmitters and receivers. IIRC, that material only worked when it was bathed in visible light for some time prior to use, where the absorbed visible light acted as an energy bath to provide the required energy for the photon upconversion.
Re: Colour-changing magnifying glass gives clear view of infrared light
#14Re: Colour-changing magnifying glass gives clear view of infrared light
#15Earlier quoted context omitted.
Not unimaginable, a similar coating is on the inside of fluorescent lighting tubes.
Not really, the coating on fluorescent tubes uses a quite different mechanism. The phosphor coating of fluorescent tubes downconverts UV light into visible wavelengths (is, lower energy/frequency) through the process of fluorescence. The UV photons excite the electrons of the phosphor molecules to higher energy states, after which they emit photons at lower frequencies/energies (visible light) as they fluoresce back…
The extra energy comes from visible light. To me it sounds a bit like how transistors amplify a signal without violating energy conservation.
Re: Colour-changing magnifying glass gives clear view of infrared light
#16Years ago I stumbled upon something related: it was a piece of transparent polymer or polycarbonate that would glow when exposed to infrared light. I tried to find it again repeatedly, but never managed to find it. Anyone knows this?
Re: Colour-changing magnifying glass gives clear view of infrared light
#17Earlier quoted context omitted.
Not unimaginable, a similar coating is on the inside of fluorescent lighting tubes.
Not really, the coating on fluorescent tubes uses a quite different mechanism. The phosphor coating of fluorescent tubes downconverts UV light into visible wavelengths (is, lower energy/frequency) through the process of fluorescence. The UV photons excite the electrons of the phosphor molecules to higher energy states, after which they emit photons at lower frequencies/energies (visible light) as they fluoresce back…
Thanks.
Re: Colour-changing magnifying glass gives clear view of infrared light
#18Does this glass need a power supply, or do two ir photons join to make a visible photon? A reverse of scintillation?
Re: Colour-changing magnifying glass gives clear view of infrared light
#19Years ago I stumbled upon something related: it was a piece of transparent polymer or polycarbonate that would glow when exposed to infrared light. I tried to find it again repeatedly, but never managed to find it. Anyone knows this?
Re: Colour-changing magnifying glass gives clear view of infrared light
#20This will almost certainly be used for weapons in short order. Currently if you want thermal imaging or very low light capability you have to use very expensive substrates. Being able to use CMOS detectors for MWIR/LWIR would instantly increase available resolutions by an order of magnitude at any given price point, assuming these filters are actually relatively cheap.