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Aren't rats nocturnal? Seems like a very poor study.

Lab rats are brown rats, which aren't nocturnal, but active day and night. I'm not sure that's important for a test of damage to the eye, but there you go.

Their vision is still really different to that of humans.

Sounds like you have some background on this. Would you elaborate? In particular, how the differences make the research unlikely to be meaningful with respect to humans?

I have no background in eyes but I have on rats. I can't affirm that the differences would make that study invalid.

I can however tell you a few facts about rat eyes.

- Their eyes are sensitive to ultraviolet.

- They have a dichromatic vision, two sets of cones instead of three. (some short wavelengths of ultraviolet/blue and a lot of greens)

- They cannot reshape their lenses.

- They have a lot more photo-receptors on their retina than us.

- They are something between farsighted and nearsighted.

- Poor binocular vision but big field of view.

Albino rats have more differences but I doubt they would have used any of those in a study on eyes.

Rats do get the same kind of eyes disease humans do (cataracts, etc.) however their sensitivity to light is really different. I don't think that it is ideal to use such different eyes to test LEDs sensitivity.

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