6J11.42 - Mach's Bands

See paragraph one in the procedure section.
Code Number:
6J11.42
Demo Title:
Mach's Bands
Condition:
Excellent
Principle:
Eye Perception
Area of Study:
Optics, Human Biology
Equipment:
Mach Band disks, small DC motor, 0 to 20 volt power supply.
Procedure:

Place and tighten the desired pattern disk onto the motor shaft.  Adjust the voltage on the power supply until the black or white bands that shouldn't be present are indeed clearly visible.

References:
  • Richard Held, "Contour and Contrast", Scientific American, May 1974, p. 17.
  • R. W. Pohl, "(c) Mach's Bands", Physical Principles of Mechanics and Acoustics, p. 3.

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