"670nm light devices were based on simple commercial DC torches with ten 670nm LEDs mounted behind a light diffuser embedded in a tube that was 4cm in diameter. Energies at the cornea were approximately 40mW/cm² which often resulted in a mild green after image for approximately 5-10 seconds. Participants were asked to use the light to illuminate their dominant eye every morning for 3 minutes and to repeat this daily for 2 weeks. These metrics were selected because they fell within the range used in a large number of animal experiments. 670nm illumination was largely confined to the central retina comprising the peaks in rod and cone density."
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.
