6J11.55 - Perception - Optic Tops

Code Number:
Demo Title:
Perception - Optic Tops
Depth Perception by the Eye
Area of Study:
Optics, Human Biology
Optic Top with Spirals, Spiral Cutout, CD's, and Pennies.

Spin the disk and observe it for 30 seconds without moving your eyes from the center of the disk.  If you look away from the disk and stare at another surface, the surface will appear to expand or contract.  The effects seen will depend on the direction in which the disk was spun.

A set of optics tops are in 6J11.30 with the Zoetrope.

  • Jair Lúcio Prados Ribeiro, "Myopia Glasses and Optical Power Estimation: An Easy Experiment", TPT, Vol. 53, #2, Feb. 2015, p. 101.
  • Martin Gardner, "The Bent Playing Card", TPT, Vol. 30, #9, Dec. 1992, p. 532.
  • Frank Oppenheimer, "The Study of Perception as a Part of Teaching Physics", AJP, Vol. 42, #7, July 1974, p. 531.
  • George M. Hopkins', "An Artificial Spectrum", Experimental, Science Volume Two, p. 243.
  • Martin Gardner, "The Bent Playing Card", Science Tricks, p. 74.
  • Paul Doherty and Don Rathjen, "Depth Spinner", The Cheshire Cat, p. 43.
  • Paul Doherty and Don Rathjen, "Squirming Palm", The Cheshire Cat, p. 97.
  • Janice VanCleave, "Wagon Wheel", 201 Awesome, Magical, Bizarre, & Incredible Experiments, p. 37.
  • Janice VanCleave, "Wagon Wheel", Biology for Every Kid - 101 Easy Experiments That Really Work, p. 160 - 161.
  • Raymond Bruman, "Shimmer", Exploratorium Cookbook I, p. 39.1 - 39.2.
  • Raymond Bruman, "Three Spinners", Exploratorium Cookbook I, 41.1 - 41.4.
  • Brown, "An Optical Illusion", More Science for You - 112 Illustrated Exp., p. 4.
  • Bobby Mercer, "Mesmerizing CD Top", Junk Drawer Physics, IBSN 978-1-61374-920-3, p. 1 - 4.
  • Jess Romeo, "The Original Illusions", Popular Science, Spring 2020, p. 114.

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