> Check out SAM's Laser FAQ for different methods of range finding.

I like the idea from Gordon's _The Robot Builder's Bonanza_: put two
sheets of difraction grating in front of the laser.

You then have a pattern. By looking at the pattern with a camera you can
determine all sorts of things: distance, irregularities in the surface,
slope, etc.

And if all you want to do is to find the distane with a cheap laser pointer,
just turn to somebody who knows the distance and ask him if he'll tell you
the distance if you'll give him the laser pointer...  :)

(Sort of like how you can find the height of a building with a barameter.)
--
D. Jay Newman           !
jay@sprucegrove.com     ! Xander: Giles, don't make cave-slayer unhappy.
http://enerd.ws/robots/ !

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.