Laser scanning is how some of the more delicate things are handled. Visual scanning is easy enough to do for home users, it's also useful for certain artifacts from last century like county fair audiographs - people spoke into a transducer and a pen drew the wave on a paper. Don't know if that's what they were called, but I've seen some of these demodulated, and voices from the void speak to you after 100 years.
That is neat, for the audiographs, did they originally have a way to read/playback the sound or was it just a way to capture a recording and they had no idea it would ever be heard as recorded?
It was just one of those geegaws you got at the fair. Speak into the device, it puts the audiogram on a paper and you take it home as a souvenir. There was no way to play them back.
Still neat.