I used to work in the opto business, specifically long-haul fiber-optic transmitters, so we were always working with high power lasers. The physiological effects of shooting a laser into your eye was not my area of expertise, but I remember from those days was that any single-wavelength light can cause very serious and permanent eye damage. Essentially, your iris is designed to close to control the amount of light hitting the retina, and if it fails to do so, permanent damage can occur in the retina. I think what happens in the case of lasers and LEDs is that there are wavelengths of light to which your iris does not react, allowing all of that light to just saturate the retina. Again, not my area of expertise, but that was my layman’s understanding of it. What’s surprising to me about your blue LED comment is that I thought the issue was related to the fact that our lasers were infrared, and so they were outside the visible spectrum. I thought this was the reason why the iris would not properly close to protect the retina, essentially because we could not “see” the light they were making. But, this is a diverse forum, there are probably some ophthalmologists floating around here somewhere, that could set us straight.