Page 102 - Introduction to Information Optics
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2.4. Fourier Transform Processing





                                              Reference
                                                object























                                                               Correlation
                                                                 peak






                         Fig. 2.16. Spatial invariant property of a JTC.


       The corresponding JTPS can be shown as


                                      2
                        I(p, q) = \F(p, q)\ [l + cos(2a 0p + y 0q)].  (2.44)
          By taking the inverse Fourier transform of /(p, q), we have the following
       complex light distribution at the output plane:

                       2/(x, y) (g) /*(x, >') + /(x, v) ® /*(x - 2a 0, y -
                                                                      (2.45)
                                        + /*(x, y)(x)/(x+2a 0 ,y +

       which is sketched in Fig. 2.16b. Thus, we see that the JTC preserves the shift
       invariant property.
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