[OPTICAL REVIEW Vol. 8, No. 5 (2001) 318-322]
Optical Fractional Derivative Matched Correlator
Yan ZHANG1,*, Ben-Yuan GU2 and Naohiro TANNO1,3
1Graduate Program of Human Sensing and Functional Sensor Engineering, Graduate School of Science and Engineering, Yamagata University, 4-3-16, Johnan, Yonezawa, 992-8510 Japan, 2Institute of Physics, Academia Sinica, P. O. Box 603, Beijing, 100080 China, 3JSTC, Regional Joint Research Project of Yamagata Prefecture, Yamagata, 990-2473 Japan
(Received December 6, 2000; Accepted May 28, 2001)
We suggest a new optical matched correlator which combines the fractional derivative with the conventional correlation for application to space shift-invariant pattern recognition. This new correlator possesses the favorable feature of being able to enhance the discrimination capability and anti-interference to noise ability over that of the conventional matched spatial filter. Varying the fractional order enables one to trade off between the light efficiency and the discrimination ability of the correlator.
Key words : image processing, pattern recognition, correlator, fractional differentiation