PURPOSE: Interference of a laser beam using Fresnel's mirror.
DESCRIPTION: Fresnel's mirror consists of two adjacent nearly parallel dielectric plates. The laser beam reflects at a small angle off the two plates to create interference on a distant screen. The angle of one of the plates can be independently varied about a vertical hinge in the center of the mirror. A 2cm focal length convex lens is used to focus the interference pattern on a nearby screen.
REFERENCES: (PIRA unknown.)
EQUIPMENT: Laser cart with Fresnel's mirror, 2cm focal length convex lens.
SETUP TIME: None.
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