Principles and practice of electrical engineering (1914)
Gray, Alexander, 1882-1921 · New York [etc.] McGraw-Hill Book Company, inc. · leaf 386
of 1,000,000 to 1 as determinedby the exposure of a photographic plate. The size of the pupil iscontrolled automatically by the intensity of the light and decreasesas the light intensity increases so as to limit the amount of lightthat can enter the eye. The sensibility of the optic nerve… … Ultra Red I, Ultra Violet Fig. 431.—Effect of color on the light efficiency. The light sensation produced by a given amount of radiantpower entering the eye depends on the color of the light. Whitelight is composite and, when passed through a prism, as shown inFig. 431, is divided up into its…
Electrical engineering
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