Astronomy > Stellar Astronomy DCS# 6D20.75

LASER SPECKLE



APPARATUS
green laser pointer
202-21-B5
converging lens
202-09-C2
diffusing screen
202-21-B5

DESCRIPTION
Model the effect the atmosphere and/or interstellar medium has on star light by directing the laser beam through the ground glass screen on to the projection screen.  Bright and dark patches can be seen, caused by interference of light scattered by the diffusing screen.  Move the screen around by hand for turbulence.
NOTES

Focus the beam on the screen with the converging lens for a larger pattern. 

Use a screen behind the setup to block reflections.


REFERENCE
Physics Education, Volume 31, issue 3 (May 01, 1996), p. 138-142