6h44.11 Total Internal Reflection with Triangular Slab
6h44.11 Total Internal Reflection with Triangular Slab
PURPOSE: To show total internal reflection.
DESCRIPTION: Using the black board optics a single light pencil is made incident on a 45, 45, 90 triangle. Two different methods can be used produce total internal reflection, as shown in the photographs.
In the method shown at left in the photograph the ray is incident perpendicular to the first surface and at 45 degrees to the second surface, exiting at 90 degrees and completing one total internal reflection. In the next method, shown at right above, the ray enters perpendicular to the first surface, is incident internally at 45 degrees to the second surface, is again incident internally to another 45 degree surface, and exits parallel to the intitial entrance after completing two total internal reflections.
EQUIPMENT: Black Board Optics single ray projector and triangular slab as photographed, portable white board.