Edward Sklar


The effect of the relief image in a coherent optical system was minimized by matching the average refractive index of the emulsion ne with that of a liquid of a known refractive index nl. A match of ne and nl was determined by minimizing the intensity of the first side order of the Fraunhofer diffraction pattern of a sine-wave image. A match of ne and nl can be made exactly only when the surface gelatin associated with the silver and the differential tanning effects of development are not present. Under other conditions ne is not homogeneous. The intensity of the Fraunhofer pattern was however reduced from 70% of the d.c. in air to only 0.25% of the d.c. in a liquid of nl, which approximates ne best.

Library of Congress Subject Headings

Images, Photographic

Publication Date


Document Type


Department, Program, or Center

School of Photographic Arts and Sciences (CIAS)


Not Listed


Note: imported from RIT’s Digital Media Library running on DSpace to RIT Scholar Works in December 2013.

Physical copy available from RIT's Wallace Library at TR222 .S55


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