Share Email Print

Proceedings Paper

Film Grain Noise In Partially Coherent Imaging
Author(s): P. Chavel; S. Lowenthal
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

Optical image formation (and processing) is strongly affected by film grain noise. The noise effects depend on the spatial coherence of the illumination. In this paper we shall analyse these phenomena in the case of Kehler illumination. The effective transmittance of any photographic image is instrument dependant due to diffusion by the grain (Callier effect). Thus the question arises : what is the meaningful physical quantity in image formation ? The Callier effect directly influences the contrast of weak modulations, which happens to be maximum in symmetric partially coherent illumination. Ultimately, the detection of weak modulations is not limited by the contrast but the signal to noise ratio. Using reasonable statistical assumptions for the noise behaviour, the optimal conditions for weak modulation detection will be discussed. This study is primarily devoted to'imaging problems, but it results may be partly extended to double-slit microdensitometry. In that case however, the illumination setup makes the complete study more difficult than in the K8hler illumination case.

Paper Details

Date Published: 25 October 1979
PDF: 11 pages
Proc. SPIE 0194, Applications of Optical Coherence, (25 October 1979); doi: 10.1117/12.957918
Show Author Affiliations
P. Chavel, Universite de Paris-Sud (France)
S. Lowenthal, Universite de Paris-Sud (France)

Published in SPIE Proceedings Vol. 0194:
Applications of Optical Coherence
William H. Carter, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?