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Super Resolved Imaging in Wigner-Based Phase Space      199


                 After the coded spatial information is passed through the finite
               aperture of the imaging lens, we have a multiplication of this aperture
               by the overall spectral distribution:


                              x


                      rect         U(  )G(  x −   ,p( ,t),  ,t) d    x  (6.13)
                                      x
                                               x
                              x
               We denoted the spatial width of the aperture by    x . The decoding
               mask is attached to the output plane, and thus its Fourier transform
               performs an additional convolution operation with the overall expres-
               sion of Eq. (6.13).

                                                        x

                          G d (  x −   ,p( ,t),  ,t) rect
                                  x
                                                      x
                                                                    (6.14)





                           ×   U(  )G(  −   ,p( ,t),  ,t) d  d
                                   x   x   x             x   x
               where G d is the Fourier transform of the decoding mask g d :

                G d (  x ,p( ,t),  ,t) =  g d (x, p( ,t),  ,t) exp (−2 ix  x x) dx (6.15)
                 Assuming that the decoding mask is the complex conjugate of the
               encoding mask, we have
                                       g d (x) = g (x)              (6.16)
                                              ∗
               which means that


                                              ∗
                                     G d (  x ) = G (−  x )         (6.17)
               and thus the expression of Eq. (6.14) becomes

                                                               x
                                 ∗

                     U R (  x ) =  G (−  x +   ,p( ,t),  ,t) rect
                                         x
                                                             x
                                                                    (6.18)





                             ×   U(  )G(  −   ,p( ,t),  ,t) d  d
                                    x    x   x             x  x
               where U R is the spectrum of the reconstructed image u R :

                             U R (  x ) =  u R (x) exp (−2 ix  x x) dx  (6.19)
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