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Night vision glasses: nanocrystals allow direct vision into infrared

smh.com.au

1–10 of 29 posts

Re: Night vision glasses: nanocrystals allow direct vision into infrared

#4

I wonder what other applications this could support. Better colour displays, where a monochromatic LED is converted to one of R, G and B?

I think they said it right there Military applications. And if price is low enough, you could use it to enable people to do outdoor work at night when it's less hot in arid/hot areas with less risk of injury (due to better vision), etc.

Re: Night vision glasses: nanocrystals allow direct vision into infrared

#7
Reading the article it hints at the reality that it doesn't actually work like passive glasses as it implies. the blueshift effect happens because they're using a laser to excite the crystal and it later emits the shifted light, but you have to pump a lot of energy in for that output. Simple conservation of energy implies this won't work for normal night vision applications, instead they want to shine a laser spotlight and use the reflected infrared laser light for vision. cool material science for sure, but not a replacement for nightvision goggles which don't broadcast your position with a bight spotlight.

Re: Night vision glasses: nanocrystals allow direct vision into infrared

#8

Reading the article it hints at the reality that it doesn't actually work like passive glasses as it implies. the blueshift effect happens because they're using a laser to excite the crystal and it later emits the shifted light, but you have to pump a lot of energy in for that output. Simple conservation of energy implies this won't work for normal night vision applications, instead they want to shine a laser spotlig…

> but not a replacement for nightvision goggles which don't broadcast your position with a bight spotlight.

To be fair that's exactly where NVD technology started out https://en.wikipedia.org/wiki/Zielger%C3%A4t_1229

Re: Night vision glasses: nanocrystals allow direct vision into infrared

#9

I wonder what other applications this could support. Better colour displays, where a monochromatic LED is converted to one of R, G and B?

Nanocrystals (semiconductor quantum dots) are already being used for some LCD displays to increase color gamut. Using QDs for LED emitters is an area of active R&D.

Re: Night vision glasses: nanocrystals allow direct vision into infrared

#10

Reading the article it hints at the reality that it doesn't actually work like passive glasses as it implies. the blueshift effect happens because they're using a laser to excite the crystal and it later emits the shifted light, but you have to pump a lot of energy in for that output. Simple conservation of energy implies this won't work for normal night vision applications, instead they want to shine a laser spotlig…

> Simple conservation of energy implies this won't work for normal night vision applications

Not at all. For a single photon, sure. But in aggregate many low-energy photons can charge a material to emit fewer high-energy photons. Ex. https://www.newport.com/f/near-infrared-nir-sensor-cards

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