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If your fiber network could heat the match hotter than the moon, why wouldn't the match heat the moon instead? How do you cram all the ends of those fibers (with total surface area equal to the moon) into a target smaller than the moon? Fiber optics aren't lasers.



Because reversing the system isnt straitforwards. Fiber tends to bend light back towards the middle of the fiber. Shining light back down the middle doesnt mean it will reappear at the same point, which is important for many types of lasers.

Archers see this. Many archery sights use fiber to make nice illuminated dots, without batteries or leds. The light appearing out the end of the fiber is brighter than the skin, a rare practical use of "naked" optical fibers.

https://www.nanoptics.com/service/replacement-bowsight-fiber...

The above are junk fiber (little internal lensing) but you can see the effect.




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