Fraunhofer holograms

We want to calculate the far field or Fraunhofer region for a square aperture. This aperture can be represented in one dimension as a rectangular or Rect function. Hence the Fourier transform of this will be a one dimensional sine function, where sinc(x) = sin(x)/x. The sine finction is shown in Fig. 1.3 and is one of the fundamental structures that dominates the information generated by computer generated holograms... 

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