6D30.20 • Thin Films: Soap Film Interference

Location: Cabinet 6

Photo of the Demonstration at the University of Texas at Austin:

Instructions / Notes:

• Faculty: The thin film reflection starts out clear, then develops color bands with a couple of minutes.
• White light from a slide projector is reflected off the soap bulb onto a screen.
• Please, position the reflected image so that a majority of the students can view it.
• Demo Staff: The slide projector needs a to have a blank slide installed in the vertical position.
• Please switch off the bulb and leave the fan running for a bit when the demo is not in use.

Last updated on June 8, 2026