Comment by gjs4786 | Hacker News Reader

Comment by gjs4786 | Hacker News Reader

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While interesting, this would almost be more interesting if it was discussing some of the other applications I a think of, such as photovoltaic cells. By converting IR light to visible light, they should be able to improve the efficiency of silicon-based PV cells.

Another application I can think of would be for greenhouses. By converting IR light to visible light, you can increase the amount of useful light for plants (and animals), increasing the photosynthesis (PAR) and plant growth. Mars comes to mind. Surely there would need to be a lot of refinement, but if it can increase useable light 2x, assuming the usable light increase occurs mostly 2 hours before dawn and 2 hours after dusk and dawn, and 2 hours after, for a 12 hour day, that's a 33% boost in efficiency. Half that to be conservative and ~15% is no joke, either

There is little IR light around, compared to visible light.

Plants could have evolved the ability to use IR light, but they didn't bother.

In fact, for plants it's more important being able to tightly regulate light absorption, which is why leaves are not black.

I’m not sure how I would measure this, but it doesn’t match my experience.

I have a Gen 3 WP PVS-14 that I use quite a bit. There is sufficient IR light outdoors pretty much all the time to see quite clearly with it, even with a new moon. The only time it’s difficult to use passively is if it’s extremely overcast. Even then, the tiny, weak IR LED on the device itself is enough to reach out to 50 yards or so.

Think about standing in front of a bright infrared source, like a space heater. You can't see the infrared, but you can feel it on your skin.

If you pay attention you can pick up more subtle infrared sources, for instance certain kind of light bulbs. But in general it feels pretty "dark."

this speaks more to the sensitivity of gen 3 white phosphorous than the abundance of infrared

as you say, it only takes a weak LED to work as a flood light

Only if it requires less input power than it outputs, which it probably doesn't.

A giant space film at the Lagrange point that upconverts (and down converts?) to only the photons that plants crave. Global warming and sunburns gone! Pollinators that see uv are done for, but we are going to kill them by accident anyway.

Edit: Also, put it in the windows of cars and houses and get rid of all the street lights so we can see stars again!

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