Glass Light Pipe
Safety Warnings
Warning: Laser Safety
Purpose
Demonstrates total internal reflection by guiding light through the glass walls of a bowl or baking dish. The visible light path shows the principle behind fiber optics at a macroscopic scale students can directly observe.
Figure 1:
Blue light injected at the rim travels through the curved glass wall via total internal reflection, clearly visible in a darkened room.
Figure 2:
View from above showing blue light confined within the glass wall thickness as it travels around the rim.
Figure 3:
A green laser pointer directed into the glass rim. The beam enters the glass edge and propagates through the walls via total internal reflection.
Figure 4:
A green laser travels the length of a Pyrex baking dish wall via total internal reflection. The straight geometry makes the light path easy to follow.