6D20.47 - Gratings - Babinet's Principle

See paragraph one in the procedure section.
Code Number:
Demo Title:
Gratings - Babinet's Principle
Home Made Diffraction Gratings with Wire or Hair
Area of Study:
Diffraction grating, special transparency plate with slit and slat.

Put the diffraction grating on the head of the overhead projector.  When you put the special transparency plate on the overhead and turn it on you will have a spectrum of the primary colors on the top and the secondary colors directly underneath.

  • C. Hanisch, M. Ziese, W. Oehme, "Newton's Green and Goethe's Purple - Color Experiments With LEDs", TPT, Vol. 59, #9, Dec. 2021, p. 713.
  • Akira Hitachi, Momo Takata, "Babinet's Principle in the Fresnel Regime Studied Using Ultrasound", AJP, Vol. 78, # 7, July 2010, p. 678. 
  • H. F. Webster, "A Demonstration of Babinet's Principle Using Two-Dimensional Gratings", AJP, Vol. 39, #1, Jan. 1971, p. 123.
  • C. L. Andrews, "Demonstration of Babinet's Principle", AJP, Vol. 39, #1, Jan. 1971, p. 122.

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