Adhikari: Welder's glass effectively absorbs LIGO's one-micron infrared laser light
Rana Adhikari · The Technical Challenges of Measuring Gravitational Waves - Rana Adhikari of LIGO · Y Combinator · Sep 15, 2017 · at 48:08
Caltech physics professor Rana Adhikari explains how LIGO selects ultra-black materials to absorb stray scattered infrared laser light inside vacuum tubes.
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“It has a wavelength of one micron, and so for it some of the things that look black don't work, but if you have a special kind of welder's glass, it really works. Welder's glass is good as, good at absorbing pretty much everything with a longer wavelength than green. So that's one of the best materials to use for blackening”
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