Poisson Spot
From UO Physics Demonstration Catalog
Return to Diffraction and Interference
Description:
A laser beam with a beam expander attatchment is aimed at the ball bearing which is held by the lens apparatus. The interference pattern, which is now large enough to see clearly, is projected onto a screen or wall. The bright spot at the center of the pattern, Poisson's spot, is the result of light waves being bent around the ball bearing.
A video camera will be required to show the spot in a classroom
Location:
- Laser: Shelf M-2
- Lens/Ball Bearing Holder: Shelf M-3
