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William T Rhodes

Publications and source records attributed to William T Rhodes.

2 recordsLinked to original sources

Imaging systems based on the encoding of optical coherence functions.

An imaging scheme is described that is based on the transmission of image-forming information encoded within optical coherence functions. The scheme makes use of dynamic random-valued encoding-decoding masks placed in the input-output planes of any linear optical system. The mask transmittance functions are complex conjugates of each other, as opposed to a similar coherence encoding scheme proposed earlier by two of this paper's authors that used identical masks. [Rhodes and Welch, in Euro-American Workshop on Optoelectronic Information Processing, SPIE Critical Review Series (SPIE, 1999), Vol. CR74, p. 1]. General analyses of the two coherence encoding schemes are performed by using the more general mutual coherence function as opposed to the mutual intensity function used in the earlier scheme. The capabilities and limitations of both encoding schemes are discussed by using simple examples that combine the encoding-decoding masks with free-space propagation, passage through a four-f system, and a single-lens imaging system.

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Nonuniform coherence sampling for fields produced by incoherent three-dimensional sources.

A nonuniform sampling scheme is described for measuring the mutual intensity of the wave field produced in a plane a distance z from a spatially incoherent, three-dimensional source object. Both uniform and nonuniform sampling are analyzed and discussed in detail, and comparisons of the two schemes are made. It is shown that nonuniform sampling requires fewer measurements than uniform sampling to specify the coherence function. Additionally, the smallest separation required between measurement points is larger for the nonuniform case.

Journal Article↗