6H50.90 - Haidinger's Brush

Code Number:
6H50.90
Demo Title:
Haidinger's Brush
Condition:
Excellent
Principle:
Atmospheric Polarization
Area of Study:
Optics
Equipment:
Haidinger's Brush Apparatus (Polarizer plate with cellophane tape at 45 degrees to the polarization axis that has been cut into 30 degree isosceles triangles and arranges on a Plexiglas plate).
Procedure:

Take the plate outdoors.  Look through the apparatus at different points of the sky and observe the polarization.  Polarization of clouds and other phenomenon can also be observed with this apparatus.

An alternative is to place the apparatus onto an overhead projector.  Rotate another polarizer above this and observe the patterns.

References:
  • L.-J. Thoms, et al, "Using the Naked Eye to Analyze Polarized lIght From a Smartphone", TPT, Vol 59, #5, May 2021, p. 337.
  • Bill Reid, "Haidinger's Brush", TPT, Vol. 28, #9, Dec. 1990, p. 598.
  • H. Richard Crane, "How Does the Honeybee Sense Polarization?", TPT, Vol. 28, #7, Oct. 1990, p. 504.
  • "Sky polarization", The Flying Circus of Physics, flyingcircusofphysics.com, p. 295.
  • "Haidinger's brush", The Flying Circus of Physics, flyingcircusofphysics.com, p. 319.
  • C.S. Ciaverini and T.D. Ressilye, "Polarization by Scattering", Light Science Physics and Visual Aids, p. 159.
  • C. Harvey Palmer, "Experiment B11: Demonstraion of Brewster's bands, Haidinger's Bands, and Fabry-Perot Bands", Optics - Experiments and Demonstrations, John Hopkins Press, 1962, p. 188.
  • C. Harvey Palmer, "Experiment C2: Haidinger's Brush and the Observation of Polarization in Nature", Optics - Experiments and Demonstrations, John Hopkins Press, 1962, p. 255.
  • C. Harvey Palmer, "Experiment B8: Demonstration of Fizeau and Haidinger Bands", Optics - Experiments and Demonstrations, John Hopkins Press, 1962, p. 171.
  • "Bee-brained", P. 36.


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