6D30.58 - Interference - Dusty Mirror

Code Number:
Demo Title:
Interference - Dusty Mirror
Scattered Interference
Area of Study:
Astronomy, Optics
Laser, Screen with Hole, Dust, and Mounted Regular Mirror (Not a Front Surface Mirror).

See also 6F40.80 in Optics.

Place the white screen with the hole in it onto the laser using the attached magnet.  Sprinkle a light coat of chalk dust or Lycopodium powder onto the mirror and aim the laser at it.  Adjust the mirror so that the reflection from the mirror goes directly back to the laser.  You should be able to observe the scattered interference pattern on the white screen.

  • Arnab Pal, Pradipta Panchadhyayee, Kriti R. Sahu, Debapriyo Syam, "A Novel Method for Measurement of the Refractive indices of Transparent Solid Media Using Laser Interferometry", TPT, Vol. 60, #1, Jan. 2022, p. 51.
  • Charles A. Sawicki, "Easy and Inexpensive Demonstration of Light Interference", TPT, Vol. 39, #1, Jan. 2001, p. 16.
  • Cyril Isenberg, "Laser Diffraction Experiments with Pseudoliquids and Pseudosolids", TPT, Vol. 38, #7, Oct. 2000, p. 411.
  • Javier González, Anayeli Bravo, and Karol Juárez, "Interference of Laser Light Scattered from a 'Dusty' Plane Mirror", AJP, Vol. 67, #9, Sept. 1999, p. 839. 
  • F. A. Fischbach, J. S. Bond, "Fraunhofer Diffraction Patterns of Microparticles", AJP, Vol. 52, #6, June 1984, p. 519.
  • A. K. Aggarwal and P. C. Gupta, "Scatter Light Interference Using Laser Speckles", AJP, Vol. 46, #11, Nov. 1978, p. 1193.
  • Guenter Schwarz, "Historical Note on 'White-Light Interference Fringes'", AJP, Vol. 35, #11, Nov. 1967, p. ix.
  • Robert H. Webb, "White-Light Interference Fringes", AJP, Vol. 35, #3, Mar. 1967, p. xxii.
  • T. Kallard, "Interference in Scattered Light", Exploring Laser Light, p. 183.
  • Jearl Walker, "6.110. Colored Rings from a Misty or Dusty Mirror", The Flying Circus of Physics Ed. 2, p. 287.
  • Yaakov Kraftmakher, "4.1. Interference of Light", Experiments and Demonstrations in Physics, ISBN 981-256-602-3, p. 221.

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