6C20.40 - Zone Plates

See paragraph one in the procedure section.
Code Number:
Demo Title:
Zone Plates
Focusing by Plates and Lines
Area of Study:
Zone Plates (In Optics Table), Laser (2 to 5 mw.), Beam Expander lens, White Paper Screens, Object for imaging (Razor Blade), Green Laser Pointer.

Put the beam expander on the laser and direct this expanded beam onto one of the zone plates. Observe the focusing properties and characteristics.

A CD or DVD without the silvered coating may be used as a zone plate.  Use an overhead projector or a slide projector as a light source and hold the CD or DVD near a screen to see the focusing effect.

  • Paul Gluck, "Compact Disk Optics", TPT, Vol. 40, #8, Nov. 2002, p. 468.
  • Vicente Moreno, Juan Felix Roman, and Jose Ramon Salgueiro, "High Efficiency Diffractive Lenses: Deduction of Kinoform Profile", AJP, Vol. 65, #6, June 1997, p. 556.
  • Charles W. Clark and Yurii N. Demkov, "Making Zone Plates with a Laser Printer", AJP, Vol. 59, #2, Feb. 1991, p. 158.
  • H. Malcolm Childers and David E. Stone, "Solution to the Fresnel Zone Plate Problem", AJP, Vol. 37, #7, July 1969, p. 721.
  • Ol-23:  Freier and Anderson, A Demonstration Handbook for Physics.
  • Wallace A. Hilton, "I-15", Experiments in Optical Physics, p. 41.
  • T. Kallard, "Optical Method for Producing Zone Plates", Exploring Laser Light, p. 234.
  • C. Harvey Palmer, "Experiment B13: Demonstration of Fresnel Diffraction by Circular Apertures and Obstructions",  Optics - Experiments and Demonstrations, John Hopkins Press, 1962.

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