Lasers are pretty much magic — it’s all done with mirrors. Not every laser, of course, but in the 1980s, the most common lasers in commercial applications were probably the helium-neon laser, which used a couple of mirrors on the end of a chamber filled with gas and a high-voltage discharge to produce a wonderful red-orange beam.
This is a companion discussion topic for the original entry at https://hackaday.com/2024/04/24/more-mirrors-and-a-little-audio-mean-more-laser-power/