The Curious Bands of Talbot.

We call attention to an old phenomenon that can still intrigue students in a contemporary physics course. Talbot's bands are investigated in an undergraduate laboratory project by utilizing commonly available apparatus. Variations of band spacing throughout the visible spectrum are measured. The effects on the pattern of retardance of the thin glass plates in the system and of the width of the grating or prism also are observed. An elementary theory is applied to describe these measurements and observations.