Purpose:Illustrate two-slit interference using microwaves.
Description:Microwaves from the source at the right pass through a pair of slits and interfere in the region to the left of the slits. The interference pattern is picked up by a microwave receiver and displayed for the class using the overhead projector microammeter. The photograph at the left shows the receiver at the central maximum; in the center photograph the receiver is at the first side minimum.