6D30.85 - Interference - Microscope Slide and Soldering Gun

See paragraph one in the procedure section.
Code Number:
Demo Title:
Interference - Microscope Slide and Soldering Gun
Interference & Thermal Expansion
Area of Study:
Laser with expanding lens, microscope slide, soldering gun.

Reflect the expanded laser beam off of the microscope slide and onto the screen.  A readily visible interference pattern should be observed.  Heat the soldering gun and hold the tip to the back side of the slide.  The thermal expansion of the slide should change the interference pattern a great deal where the tip is touching the slide.

  • Kevin T. Kilty, "A Simple Interferometer", TPT, Vol. 35, #8, Nov. 1997, p. 507.
  • T. Kallard, "Interference Demonstration with Plane Parallel Glass Plates", Exploring Laser Light, p. 117.
  • Gordon McComb,  Lasers, Ray Guns, & Light Cannons - Projects from the Wizard's Workbench, p. 154.

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