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You can use the Fresnel lens in an old projection TV as a laser.

https://www.youtube.com/watch?v=OmlXR2nsis4




Laser is light amplification by stimulated emission of radiation. Fresnel lens doesn't amplify light it focuses it. It is not stimulated, it is just passive component.


This is true, but I don't think many people think of laser as anything other than "dangerous light." That's how I used it. Colloquial meanings can be frustrating when they clash with the technical meaning, but trying to fight them is typically futile.

https://www.merriam-webster.com/dictionary/laser

>> "2 : something resembling a laser beam in accuracy, speed, or intensity "

I gave up on fighting "CPU means the entire computer" a long time ago.


> This is true, but I don't think many people think of laser as anything other than "dangerous light."

"Many people" have taken first year physics, or at least read a wikipedia article, and understand that the defining feature of a laser is its coherence.

But, sure. It's 2020. We live in a post-factual society, words have no meaning and it's impossible to know anything. Why resist?




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