Abstract

We have previously reported a technique for suppressing one of the two first-order diffracted beams from binary phase-only gratings written onto spatial light modulators by writing the cosine and sine filters onto separate halves of a spatial light modulator. We report the use of this phase-encoding technique for constructing binary approximations to continuous phase-only filters for use in optical correlators. Computer simulations of these filters are given. These results show that our new filters do not recognize inverted occurrences of the input object in contrast to binary phase-only filters made using previous techniques. In addition, these filters yield a greatly improved SNR over earlier types of filters.

© 1989 Optical Society of America

Optical correlator performance of binary phase-only filters using Fourier and Hartley transforms

Don M. Cottrell, Roger A. Lilly, Jeffrey A. Davis, and Timothy Day
Appl. Opt. 26(18) 3755-3761 (1987)

Improved synthetic discriminant function performance using Fresnel lens-encoded binary phase-only filters

Jeffrey A. Davis, Stuart H. Drayton, Don M. Cottrell, and Jeffrey E. Davis
Appl. Opt. 29(17) 2594-2599 (1990)

Fresnel lens-encoded binary phase-only filters for optical pattern recognition

Jeffrey A. Davis, Don M. Cottrell, Jeffrey E. Davis, and Roger A. Lilly
Opt. Lett. 14(13) 659-661 (1989)

Binary encoding of gray-scale nonlinearly transformed filters for optical pattern recognition

Bahram Javidi and Qing Tang
Appl. Opt. 31(20) 4034-4041 (1992)

Amplitude encoded phase-only filters

Mary A. Flavin and Joseph L. Horner
Appl. Opt. 28(9) 1692-1696 (1989)