[sdiy] Theremin

[Paul Perry]

At 09:09 PM 6/07/04 +0200,Roman wrote:
>proffesional laser distance meters used by construction workers measure
>from 30cm up to 30m with 1mm resolution, or was it 1cm, can't remember.

I've seen distance measurers that are actually ultrasonic, but have a 
laser diode built in, so you can see where you are pointing it.
You could use a mirror to see whether the light beam is doing the measuring.

paul perry Melbourne Australia