Demonstrations

Thin Film Interference - Air Wedges with Sodium Light

Code Number :	6D30.30
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Condition :	Good
Principle :	Thin Film Interference
Area of Study :	Optics
Equipment :	Sodium Lamp with Power Supply and Accessories, Round Glass Plates (2).
Procedure :	Plug the sodium lamp into the power supply and turn on. Allow about 5 minutes warm-up time. Adjust the screens in front of the lamp so that the light is directed onto the round plates directly in front of the lamp. Place one of the plates on top of the other. As the air is driven from between the two plates interference patterns are observed.

References

Walter H. Kruschwitz, "Interference Bands Observable at a Distance From a Light Source", TPT, Vol. 44, # 4, Apr. 2006, p. 248.

Brian Jones, "The Little Shop of Physics", TPT, Vol. 34, # 8, Nov. 1996, p. 514.

G. R. Davies, "Interference and Diffraction Corridor Diffraction," TPT, Vol. 33, # 4, p. 244 - 247, April 1995.

Zenon Gubanski, "Interference of Light Coming From an Air Wedge", TPT, Vol. 7, # 8, Nov. 1969, p. 455.

Walter H. Kruschwitz, "Interference Bands Observable at a Distance from a Light Source", TPT, Vol. 13, # 5, May 1975, p. 296.

C. R. Wheeler, P. N. Hendricksen, R. D. Ramsier, "Visibility of Thin-Film Interference Fringes", AJP, Vol. 72, # 2, Feb. 2004, p. 279.

D. G. Sargood, "On the Use of Float Glass in Lecture Demonstration Experiments in Optics", AJP, Vol. 46, (2), Feb. 1978, p. 187.

Ol-15,18: Freier and Anderson, A Demonstration Handbook for Physics.

O-455: "Air Wedge Between Glass," DICK and RAE Physics Demo Notebook.

L-70: Richard Manliffe Sutton, Demonstration Experiments in Physics.

"7.3: Interference and Diffraction," Cunningham and Herr, Hands-On Physics Activities, p. 467.

"Bridge Light," The Magic Wand & Other Experiments in Light & Color, Exploratorium, p. 12-15.

"Bright Light," Exploratorium Science Snackbook, 13-1.

Raymond Bruman, "Bridge Light," Exploratorium Cookbook I, p. 9.1 - 9.2.

Mail Questions and Comments to: Dale Stille