I built something similar from the high power red projector LEDs and cpu heatsinks about 8 years ago, but it was too cumbersome to use enough to get any sense of effects. Also I drove them a little too hard and you needed tanning bed glasses to be close enough to try it out.
Back when I built mine I had read a little of the theory behind them. Seemed to make sense. I don’t recall finding any solid scientific info.
I use an AA light with a red LED swap, on my eyes, pimples, and bruises…
Have not tried the larger coverage panels, like the one you linked (thanks for that, always appreciate a post with links). I would buy the mixed LED option, because Ive seen a lot of red light studies that use far red (730, 850, 900nm), not just visible red (660nm).
My understanding is red light is not harmful to tissue… eye protection that applies to UV light, does not apply to red spectrum.
the thread that got me interested in red light is this one:
I used to have a pile of webpages bookmarked on this topic. Some were peer reviewed studies. There are very specific wavelength ranges, four primary peaks, ranging from orange-red out through ~900nm IIRC. Finding emitters to match these peaks is expensive and complicated since most are different footprint/Vf/If. I settled on the idea of using a red filtered halogen bulb typically used in reptile terrariums. LEDs would be more efficient if you could match the peaks and would allow more functional power density before heat tolerance is reached, but low and slow IMO is better anyway. When I was having some stress induced skin issues, I was about to try this… but I never came around to it.
Found a familiar image real quick… Some data shows the visible peak split in two with peaks at ~620 and 675nm.
