Alternate Theory of Color Perception
Szeszol, Jim                             Naperville Central H.S.
                                         420-6417
                           
Objective:
To observe an alternative theory of color perception.
Apparatus needed:
A) Color wheel(s), wooden safety matches (for spindles), masking 
tape. 
B) Black and white slide positives.
Procedure:
A) Activity - assemble color wheel(s) and spin; observe colors in 
   daylight and under fluorescent light.  Have students form a possible theory.
B) Land projections - two black and white slides (positives) are 
   prepared and projected as outlined in "The Physics Teacher," March
   1968, p. 129.  Full color images, not possible with Newtonian 
   theory, are produced.
Discussion:
Edwin Land's (of the Polaroid Land Corp.) "Retinex Theory" 
states that the eye processes black and white gray scales using three 
photoreceptors.  Each photoreceptor processes the signals differently 
and then combines the processed information to produce colored images 
in the brain.
References:
Land, Edwin H.  "Experiments in Color Vision," Scientific American, 
May 1959.
Land, Edwin H.  "The Retinex," American Scientist, 52, 1964.
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