Quote:
Originally Posted by programmer
I'm no expert, but staying 'coherent' doesn't mean the light stays tight, focused and powerful, AFAIK.
http://onlinedictionary.datasegment....herent%20light
Lots of other reasons anyway.. beam divergence, aiming the beam at a 6mm target (eye pupil) over few hundred meters, IR filters in the laser, etc... |
The low degree of
angular dispersion of coherent light beams also allows
the use of such light in laser ranging, over distances
A lot of the cheap one people are buying of ebay do not have the ir filters.
as far as from the earth to the moon.