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Not really, the coating on fluorescent tubes uses a quite different mechanism. The phosphor coating of fluorescent tubes downconverts UV light into visible wav
by jeffwass 5y ago
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 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.
- philprx 5y agoDo you have an URL or reference for this film? Thanks.
- ted_dunning 5y agohttps://www.newport.com/p/F-IRC2-F?xcid=goog-pla-F-IRC2-F&gclid=EAIaIQobChMIu_y31dDU9AIV-BmtBh1k1Qu7EAQYAiABEgJjc_D_BwE https://www.newport.com/p/F-IRC2-F?xcid=goog-pla-F-IRC2-F&gc...
- moring 5y ago"These shaking molecules can donate their energy to visible light that they encounter" The extra energy comes from visible light. To me it sounds a bit like how transistors amplify a signal without violating energy conservation.
- tinus_hn 5y agoThere is no fundamental limitation that would prevent the conversion of multiple IR photons into a single photon of some kind of visible light. The purpose here is to make the light visible, not to do a 100% efficient conversion.