6F10.20 - Filters

Code Number:
Demo Title:
Spectral Selectivity
Area of Study:
Optics, Astronomy
Filters - Edmund Scientific Set, Filters - Various glass, and Plastic.

We have used the filters in conjunction with the photoelectric effect demo (7A10.30) to show that the energy of light greatly affects the amount of radiation detected at the photocell.

In this case the detector is a photocell, but this can be equated to the eyes, radios, solar cells, or any other electromagnetic detector.

The set of three large round filters are Subtractive filters. The disks are cyan, magenta, and yellow. These can be used to show colors as they are used in the printing industry.

  • Robert M. Williamson,  "Filters for Color Mixing", TPT, Vol. 36, # 1, p.  22, Jan. 1998. 
  • David Keeports,  "When Yellow and Blue Make Red",  TPT, Vol. 33, # 7, p. 430, Oct. 1995.
  • James C. Kernohan, "Red, White, Blue, and Black", TPT, Vol. 29, # 2, Feb. 1991, p. 113.
  • Gordon McComb,  "Filters", Lasers, Ray Guns, & Light Cannons, p.  40- 42.
  • Janice VanCleave, "Use Colored Filters to Send Secret Messages", Super Science Challenges, p. 132.
  • Janice VanCleave, "51, Make a Color", Teaching the Fun of Physics, p. 82.
  • Janice VanCleave, "52, Secret Message", Teaching the Fun of Physics, p. 83.
  • Jearl Walker, "6.132, Colors of Green Glass and Green Velvet", The Flying Circus of Physics Ed. 2, p. 298.
  • Jearl Walker, "6.96, Alexandrite Effect", The Flying Circus of Physics Ed. 2, p. 279.
  • John H. Moore, Christopher C. Davis, Michael A. Coplan,  "Filters",  Building Scientific Apparatus 2nd Edition,  p. 164-168.
  • T. D. Rossing, C. J. Chiaverina, "Spectral and Monochromatic Filters", Light Science, Physics and Visual Arts, p. 181.
  • T. D. Rossing, C. J. Chiaverina, "Multilayer Interference Filters", Light Science, Physics and Visual Arts, p. 113.

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