Check out SAM's Laser FAQ for different methods of range finding.
Google for SAM's Laser FAQ (hosted on repairfaq.org) if you are generally
interested in lasers and everything around them (function, construction,
uses,...)

Here's the link to some Laser Experiments (range finder too) from SAM's
Laser FAQ: http://www.repairfaq.org/sam/laserexp.htm

MfG,
Do.Pe.

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