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> BUT about 10 years ago, it became practical to use frequency doubling in LEDs to generate light really close to the mercury light - the LEDs are not carcinoge
by detaro 5y ago
> BUT about 10 years ago, it became practical to use frequency doubling in LEDs to generate light really close to the mercury light - the LEDs are not carcinogenic and cataractogenic.
What makes the LED light not dangerous that way? As far as I understand, what makes UVC effective is also what makes it dangerous.
- Gibbon1 5y agoI did the same as the parent. The answer is that mercury based UV lamps produce a spiky broad spectrum including emission lines really where you don't want them. And not very much at the frequency that is most effective at destroying RNA/DNA. 220nm is important because it's very effective at cross linking thymine. UV LEDs can be manufactured to produce a very narrow spectrum centered on 220nm. So with an LED the total amount of UV produced is much less and doesn't include problematic frequencies that cause eye and tissue damage. Supposedly, I don't work in this space. Note most UV LED's aren't suitable for sterilization. If it comes in a plastic case and costs 30 cents, it's certainly not.
- ecesena 5y ago> UV LEDs can be manufactured to produce a very narrow spectrum centered on 220nm Does anyone know of any manufacturer? I don't think they exist yet?
- mrsulaj 5y agoFull disclosure: I'm the founder of UVX Inc., a University of British Columbia company integrating Far-UVC technology into smart devices. Unfortunately, current state-of-the-art UV LEDs do not produce enough power at the 220nm wavelength to be commercially viable. The current state-of-the-art uses KrCl excimer lamps to generate this light, with optical filters to eliminate spillage in the undesired frequencies (> 230nm).
- Gibbon1 5y agoThanks for the reply. > KrCl excimer lamps https://en.wikipedia.org/wiki/Excimer_lamp https://en.wikipedia.org/wiki/Excimer_lamp