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- IR is just super red light. It's not significantly more dangerous as looking at a lightbulb can be, except human eyes cannot perceive IR and can't contract pupils or stare away by reflexes.

- UV is baby step towards X-rays. It's technically super blue light, but it's entering region where lights start splitting chemical bonds and bleaching stuffs like pathogens and human eyes.

- LASER is perfectly parallel beams of light. Because it's perfectly parallel and do not diverge, it behaves like sun under magnifying glass at all points in its path, which can be dangerous when the "sun" is high and "glass" focusing it tight.

High power IR lamp illuminating audiences from afar is almost safe as any searchlights. IR lasers can be dangerous. UV lamps are not so safe, UV lasers would be bad.




> LASER is perfectly parallel beams of light. Because it's perfectly parallel and do not diverge, it behaves like sun under magnifying glass at all points in its path

To first approximation, in the typical situations regular people deal with lasers. Inverse square rule still applies; laser light does spread out with distance.

That nitpick aside, your description is spot on.


Standard off the shelf, 5W white LED emitters come with a warning against eye damage from staring directly into the beam. Those suckers are bright, and while your pupils will automatically contract to minimize damage from visible light, the same is not true when they're hit with IR.


IR isn't just super red light, it's heat. Lol


So is regular light, in that sense. The IR that's used for this kind of application is 'near infrared', which is much closer to light than the IR emitted by most warm objects.


It's light, and some animals can see it, just not us. https://en.wikipedia.org/wiki/Infrared has some pictures from the right kind of cameras and telescopes.


It is the primary frequency of black body radiation at Earthly temperatures. But it is not the heat itself.




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