Total Internal Reflection with Blackboard Optics

PIRA 6A44.10

Total internal reflection can be demonstrated with the use of a Blackboard Optics ray box and large plexiglass prism, as shown at near right. The plexiglass prism can be rotated to show refraction at angles of incidence greater than, equal to, and less than, the critical angle.

The ray box requires 10 or 12 V AC.  The Blackboard Optics Transformer shown below provides this. The room needs to be dark in order for the rays to be clearly visible to a large class.