Glass Bead Reflector-Variable Index
This applet shows how light is transmitted and reflected in a glass bead with a reflective coating on the back side. These types of beads are used in reflective materials worn by highway workers so that they are easy to see. You can change the angle that light enters the bead by moving the dot at the right end of the "incident ray" You can change where the light enters the bead by moving the lower dot on the right side of the bead. You can change the size of the bead by dragging the yellow circle on the top of the bead.