6A44.42 - Frustrated Total Internal Reflection - Steal the Signal

Code Number:
Demo Title:
Frustrated Total Internal Reflection - Steal the Signal
Barrier Penetration, Critical Angle, and Cladding Properties
Area of Study:
Laser, Light Pipes, Small Clamps, Glycerin, and Watch Glass.

See also 7A50.10 in Modern Physics.

Two sets of fiber optics light pipes from the fiber optics demonstrator kit may be used to show some interesting effects. Press them together with a C-clamp where the light beam bounces off the edge in one and the beam will be directed into the other pipe. Or you can wet the end of one of the light pipes with glycerin and press to the other light pipe at the position where the laser beam strikes the edge. The laser beam should be directed outside the first light pipe and into the second.

  • G. Calzà, T. López-Arias, L.M. Gratton, S. Oss, "Playing with Refraction", TPT, Vol. 48, # 4, April 2010, p. 270.
  • Dale Edgar, "Simulating Optical Fibers", TPT, Vol.26, # 8, Nov. 1988, p. 504.
  • A. A. Stahlhofen, "Comment on 'Frustrated Total Internal Reflection: A Simple Application and Demonstration, AJP, Vol. 71, # 5, May 2003, p. 494", AJP, Vol. 72, # 3, March 2004, p. 412.
  • F. P. Zanella, D. V. Magalhaes, M. M. Oliveira, R. F. Bianchi, L. Misoguti, and C. R. Mendonca, "Frustrated Total Internal Reflection: A Simple Application and Demonstration", AJP, Vol. 71, # 5, May 2003, p. 494.
  • Joe L. Ferguson, "A Many-Concept Optics Demonstration", AJP, Vol. 52, #4, Apr. 1984, p. 377.
  • I. Godeny, F. J. Kedves, and D. Beke, "Total Reflection of Light and Water Waves", AJP, Vol. 45, # 6, June 1977, p. 550.
  • T. Kallard, "Demonstrating the Penetration of Laser Light Beyond a Totally Reflecting Interface", Exploring Laser Light, p. 65.
  • T. Kallard, "Fingerprint Observation by Frustrated Total Reflection", Exploring Laser Light, p. 64.
  • 0-258: "Light Vanish in Oil/Vaseline", DICK and RAE Physics Demo Notebook.

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