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by jdietrich 3222 days ago
It's not difficult to track eyes consistently using computer vision. It's not difficult to aim a laser beam using a mirror galvanometer. If you're struck in the eye with a UV laser beam, the blink reflex doesn't kick in - by the time you've noticed the pain in your eyes, it's already too late. The beam doesn't have to track with particularly high accuracy to cause certain blindness, especially if there's an array of beams.

A decent hardware hacker could build an area-denial laser turret in a long weekend with a couple of hundred bucks of parts. I hope to god that nobody ever does.
1 comments
wnkrshm 3222 days ago
A UV-laser would be humane, since UV (and shorter wavelengths) will interact with the outermost portion of your eye - visible light or the near IR (up to 1500) is what your imaging system operates on and it's focused onto the retina.

Edit: Also, the blink reflex isn't fast enough to save you from damage if the Class is higher than Class 2 (and even then it's a roll of the dice, since there are some who don't have that fabled reflex).

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gambiting 3222 days ago
Can you expand on why that would be humane?
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wnkrshm 3221 days ago
Shorter wavelengths (UV, extreme UV) are absorbed at the surface of organic tissue (and many other materials) and lead to ablation or heat transfer at the surface. So with shorter wavelengths, it'll mostly scar the cornea, which can be reshaped again using short wavelengths with a LASIK.

It might also cause damage to the lens and lead to cataracts, which can also be partially compensated today by getting a lens implant.

These ways of damaging your eye are extremely more preferable than having your retina or your nerves damaged in any way, since for that, no method of remedy exists yet.

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Filligree 3222 days ago
At a guess, it might be possible to at least partially fix the damage afterwards, by scraping off the damaged cells.

I wouldn't call that "humane", and it is a guess; it might not work at all. Nothing to do with war is 'humane', though.

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wnkrshm 3221 days ago
You're right, my choice of words was poor there, I didn't want to imply that there are any humane weapons or ways to wage war.

I think what I was trying to say is that if I could choose the wavelength to hit my eye, I'd pick extreme UV.

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