
Declining eyesight improved by looking at deep red light - open-source-ux
https://www.ucl.ac.uk/news/2020/jun/declining-eyesight-improved-looking-deep-red-light
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MurMan
Stand by for a flood of "healing light" LED lights with all sorts of health
claims.

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pujjad
What's the best way to make them red torches?

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eyeball
How about a grow light like this?

[https://www.amazon.com/gp/aw/d/B0744GY7TP](https://www.amazon.com/gp/aw/d/B0744GY7TP)

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pujjad
What a great idea, thanks!

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ALittleLight
From the description:

"Extremely bright, do not look directly at the LED bulbs when the light is
working."

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pujjad
Maybe have them shine on to a neutral surface with some distance.

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ALittleLight
Possibly. Whenever I see this paper I'm reminded of the gap of not having some
12 dollar low power red led flashlight Amazon link. I'm looking at AliExpress
right now and idly considering buying a few purportedly red led flashlights
and finding a way to test them to confirm they are the right wavelength and
relatively low power.

Buy a thousand flashlights at 4 a piece on AliExpress, offer on Amazon at 12,
write a blog post about checking this effect on my parents, link to the paper,
share on hackernews and other sites with an Amazon link...

Still, I'd be kind of surprised if you could sell a thousand flashlights like
this, and it seems a fair amount of risk and effort for a few thousand return.

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eyeball
I'd worry about getting LEDs that put out UV or some unintended harmful
wavelength.

Is there reliable / cheap way to test wavelength being emitted?

