QC 351 A7 no. 24 / A lens system may be judged by its ability to relay information from
object to image. A pertinent criterion of optical quality is h, the change
in entropy between corresponding sampling points in the object and image
planes. Since h is a unique function of the optical pupil, for a given
bandpass 20 of the object, through the proper choice of a pupil function it
is possible to maximize h at a given Q. Physically, the optimum pupil function is an absorption coating applied to a diffraction - limited lens system.
A numerical procedure is established for determining, with arbitrary accuracy, the optimum absorption coating, the resulting transfer function, and
the maximum h, all at a given 0. These quantities are determined, both for
the one -dimensional pupil and the circular pupil, in the approximation that
the optimum pupil function may be represented as a Fourier - ( Bessel) series
of five terms. The computed values of
hmax,
at a sequence of 52 values, are
estimated to be correct to 0.2% for the 1 -D pupil, and to 0.5% for the
circular pupil. The optimum pupil functions are apodizers at small S2 and
superresolvers at large 0. Finally, we use the computed curve of hmax to
relate the concept of "information transfer" to that of "classical resolving
power ": we show that a binary object (as defined) cannot radiate information to the image when the spacing between object sampling points is less
than 0.87 times the Rayleigh resolution length.
| Identifer | oai:union.ndltd.org:arizona.edu/oai:arizona.openrepository.com:10150/621617 |
| Date | 15 March 1968 |
| Creators | Frieden, B. Roy |
| Publisher | Optical Sciences Center, University of Arizona (Tucson, Arizona) |
| Source Sets | University of Arizona |
| Language | en_US |
| Detected Language | English |
| Type | Technical Report |
| Rights | Copyright © Arizona Board of Regents |
| Relation | Optical Sciences Technical Report 24 |
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