6C20.40 - Zone Plates

See paragraph one in the procedure section.
Code Number:
6C20.40
Demo Title:
Zone Plates
Condition:
Good
Principle:
Focusing by Plates and Lines
Area of Study:
Optics
Equipment:
Zone Plates (In Optics Table), Laser (2 to 5 mw.), Beam Expander lens, White Paper Screens, Object for imaging (Razor Blade), Green Laser Pointer.
Procedure:

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.

References:
  • 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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