Physics at the University of Virginia
Academics People Research Announcements Facilities Adminstration Home Updates

Return to Demo Lab Homepage

Al Tobias (wat4y) - Office: Gibson S123 & Physics 218, (434) 924-0538


Physics Demo Manual

Demonstrations are cataloged according to PIRA Bibliography

PLEASE REQUEST DEMOS WELL IN ADVANCE

Due to Physics Building renovations, the lead time to set up demo requests has increased due to the need to transport equipment across campus. Please be kind and let me know well ahead of time what you need.


Choose a Topic or Enter a keyword to search:
I cannot find what I want!


You have selected the following Demos:
  • None Selected

Choose a subtopic:
(Clicking a green button will add that demo to your list)
 Geometrical Optics
 Diffraction
  video  - Interference and Diffraction
 Arago's (Poisson's) Spot
 Razor Edge Diffraction
 Interference
 Color
 Polarization
 The Eye

Arago's (Poisson's) Spot

Purpose:

A non-intuitive illustration of the wave theory of light.

Procedure:

Point the setup at the screen (the farther away from the screen, the better). Note that the green laser has a beam expander on it. Therefore, place your "second" lens at the focus of the laser beam to minimize effects of lens abberation, since at the focus one minimizes the area the light projects on the lens.

Hints:

The razor edge and the Poisson spot are on the same mount. We have used 188mm or -20cm lens.
In room 203 use a regular camera and #4 light setup to project the diffraction pattern on the big screen.

Equipment:

  • Small Bead on Glass Plate
  • Optical Stand
  • Laser
  • 18.8 cm Lens and stand