Spatial and temporal coherence of filtered thermal light.

Appl Opt

Departimento di Fisica, Università degli Studi di Genova, Via Dodecaneso 33, 16146 Genova, Italy.

Published: November 2003

When a filter is placed in front of a double slit illuminated by a primary source of finite extent, the theory of partial coherence predicts that in general the interference fringes do not acquire unit visibility even as the passband of the filter is made arbitrarily narrow. The effect of reducing the filter bandwidth is that the visibility of the fringes tends to the modulus of the spectral degree of coherence and that more interference fringes become visible. A systematic experimental verification of these theoretical predictions is lacking so far and is provided here from the use of a highly sensitive CCD camera.

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http://dx.doi.org/10.1364/ao.42.006239DOI Listing

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