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What about an infrared laser? Something where a microburst would melt delicate insect wings, but a direct hit on a human eye would just warm it up a tiny bit. Possible?

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You basically can't make laser pulses safe and melt things at the same time, because by nature of having the energy in a short pulse created heat doesn't have time to distribute, so it doesn't matter if you hit a tiny thing or a tiny spot on a larger object, the damage done locally is the same.

I’m confused, are you saying that the minimum amount of energy in an infrared pulse sufficient to melt a fly’s wings (< 1mm) would necessarily also damage a human eye?

I have to believe there is a threshold value of safety, particularly with IR. You can tell me I’m wrong, but please provide a bit of physics to justify it.

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