6C20.20 - Diffraction - Hair and Pins

Code Number:
Demo Title:
Diffraction - Hair and Pins
Edge Diffraction
Area of Study:
Optics, Astronomy
Helium-Neon Laser (2 to 5 mW), Optics Bench, Tape Measure (25 ft), Hair Stretched on a 35mm Slide Holder, and Styrofoam Block with Pins and Washers.

Screw the diffusing lens onto the laser and place either the hair, pins, or washers into the diffused beam.  A shadow of the object should appear on the screen with multiple bright and dark outlines.

  • Rebecca Messer, "Single Slit Interference Made Easy with a Strand of Hair and a Laser", TPT, Vol. 56, #1, Jan. 2018, p. 58.
  • Thomas B. Greenslade Jr., "Diffraction by a Cat's Whisker", TPT, Vol. 38, #7, Oct. 2000, p. 422.
  • Robert P. Bauman, "Diffraction and Non-Diffraction Fringes", TPT, Vol. 34, #6, Sept. 1996, p. 339. 
  • G. R. Davies, "Interference and Diffraction Corridor Demonstrations", TPT, Vol. 33, #4, Apr. 1995, p. 244.
  • Walter Scheider, "Bringing One of the Great Moments of Science to the Classroom", TPT, Vol. 24, #4, Apr. 1986, p. 217.
  • Robert Barrett, Kenneth Lodge, and Martha Schreffler, "Photographing Diffraction Patterns Without a Camera", TPT, Vol. 16, #3, Mar. 1978, p. 180.
  • R. C. Nicklin and J. Dinkins, "Laser Diffraction Photography", TPT, Vol. 12, #5, May 1974, p. 295.
  • Salvatore Ganci, "Fraunhofer Diffraction by a Thin Wire and Babinet's Principle", AJP, Vol. 73, #1, Jan. 2005, p. 83.
  • John Macdonald and Seán V. O'Leary, "Measuring the Diameter of a Hair with a Steel Rule", AJP, Vol. 62, #8, Aug. 1994, p. 763.
  • Yeu Pyng Hwu, "Diffraction Pattern of a Hair", AJP, Vol. 45, #4, April 1977, p. 404.
  • S. M. Curry and A. L. Schawlow, "Measuring the Diameter of a Hair by Diffraction", AJP, Vol. 42, #5, May 1974, p. 412.
  • T. C. Sayetta, "Interference Fringe Demonstrations", AJP, Vol. 41, #7,  July 1973, p. 931. 
  • Allen L. Moen and David L. Vander Meulen, "Fresnel Diffraction Using a He-Ne Gas Laser", AJP, Vol. 38, #9, Sep. 1970, p. 1095.
  • Guenter Schwarz, "Historical Note on 'White-Light Interference Fringes'”, AJP, Vol. 35, #11, Nov. 1967, p. ix.
  • John Harris, "Photographing Diffraction Effects", AJP, Vol. 35, #2, Feb. 1967.
  • "O-532. Human Hair Diameter with Laser", DICK and RAE Physics Demo Notebook, 1993.
  • "O-530. Needle, Slit, and Razor Blade", DICK and RAE Physics Demo Notebook, 1993.
  • "M-034. Hair Diameter", DICK and RAE Physics Demo Notebook, 1993.
  • T. Kallard, "Measuring the Diameter of a Hair by Diffraction", Exploring Laser Light, p. 202.
  • Yaakov Kraftmakher, "4.2, Diffraction of Light", Experiments and Demonstrations in Physics, ISBN 981-256-602-3, p. 227.
  • Charles Taylor, "3.15", The Art and Science of Lecture Demonstration, p. 149 - 150.
  • T. D. Rossing and C. J. Chiaverina, "5.6, Diffraction", Light Science, Physics and Visual Arts, p. 113.
  •  Roman Ya. Kerzerashvili, "Abstract: Advanced Optics with Laser Pointer and Metersticks", 2005 Apparatus Competition, Salt Lake City, UT.

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