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CHAPTER6





                            Super Resolved Imaging



                              in Wigner-Based Phase


                                                             Space






               Zeev Zalevsky
               School of Engineering, Bar-Ilan University
               Ramat-Gan, Israel






          6.1 Introduction
               Super resolution (SR) is a field integrating the sciences of optics with
               the expertise of image processing and computer vision science. 1–7
               Basically any imaging system, digital as well as a human eye, has a
               limited capability to separate close spatial features. This limitation can
               be related either to the diffraction or to the geometry of the imaging
                           1
               sensing array. In the case of diffraction, given an imaging lens with
               limited aperture size, not all the rays reflected from the object are
               collected by the lens. According to Rayleigh criteria, 8–10  this limitation
               is proportional to the product of the wavelength of the illumination
               and the F number of the optics (the ratio of the focal length to the
               diameter of the lens). Thus, the smaller the F number, the better the
               spatial separation becomes. In the case of the geometry of the sensing
               array, the smaller the pixels are, i.e., the denser the spatial sampling of
               the space, the better the capability to reconstruct closer point sources
               originated from the imaged object. 1
                 To overcome the limitation of a given imaging system, one may
               convert the spatial degrees of freedom, which before could not pass
               through the limited spectral bandwidth of the imaging system, into
               other domains that the imaging system can transmit, and then after



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