gyre wrote:We examined a laser sold as green, which was a red laser converted to green.
I think this amplified it's effective output at the same time.
The manufacturers didn't care about regulations.
Impressive results, but far brighter than legal.
I don't understand what you mean? You can't convert a red laser to green. Green lasers are made by converting IR into green by "pumping" it through wavelength-doubling crystals. Visible red is not used, however.
Risky wrote:I was warned about the blue ones this year, from a friend who makes lasers and has put on several shows this summer in Reno.
He suggested high rated UV protection glasses to protect your eyes from injury.
There are available in shades or clears.
Those are generally not going to help you at BM. UV protection glasses have different meanings, but generally means wavelengths less than 400nm (UVA and UVB protection). People might think this means sunglasses, but these are even worse than no goggles because the darkness will dilate your pupils, and they will not block against blue light, only UVA and UVB, which is around 400nm, not 445nm. Clear, if I get your meaning as non-colored, is not going to help you in the least either. These are blue
lasers (445nm), not UV lasers. Maybe they block UVB or something, but if you can see blue, you can see those lasers, and they can blind you. Nor are many goggles designed to protect against the kinds of power densities as these lasers have. A laser beam is a lot different than the UV that might come from, for example, welding arcs (though neither is good).
Even if protective, such goggles would be generally useless for most people. People play with these lasers night, not during the day, and nobody is going to wear welding goggles, or any goggles for that matter, that reduce the visibility of light during the night. There are potentially usable goggles, but certainly not for cheap. I've got actual laser protection goggles for 445nm through UV, and they cost about $100. They're yellow tint, for maximum visible light throughput outside the protection range, but I can't imagine people wanting to wear them at night, nor should they. I also tested other goggles that were similar (but uncertified) to see if there were cheaper alternatives for protecting against 445nm--they didn't hold up, and started melting quickly. Of course you won't have a sustained beam on your face, but still, even in short bursts, it didn't protect.
Cheap, protective goggles are red laser enhancement goggles: goggles with red filters designed to make it easier to see red laser beams, but in doing so help filter out other wavelengths. Nobody would use one at BM, let alone at night. Using them in full daylight takes its toll on your vision, and reduces visibility substantially. I wouldn't even bother with those.
Your best protection is distance, because the beam diverges and also scatters on particles in the air as it passes through them. The 445nm lasers are also multimode and have poor beamspecs, causing them to perform poorly at distances. This doesn't mean you can't still get hurt, but it gives you time to close your eyes or look away, and get out of the vicinity of an idiot who doesn't understand the laser in his or her hands.