Diffraction - Introduction

The apparatus for demonstrating diffraction of red and green light by patterns on a diffraction plate is shown.

On the following four pages are paired images formed by red and green laser light that has passed through one of the ten patterns, A through F, on the diffraction plate shown here. The photographs below the diffraction plate show the arrangement of laser, diffraction plate, screen, and ruler. Closeups of the patterns formed on the screen by red and green laser light after passing through pattern A (a 0.04 mm wide single slit) on the diffraction plate are included.