Diffraction pattern sampling using a holographic optical element in an imaging configuration.

The use of a segmented holographic optical element (HOE) and detector array combination to sample the power spectrum in a coherent optical Fourier transform system is discussed. Each segment of the HOE redirects the incident energy to a corresponding detector, and this performs an integration over the selected region of the spectrum. An arrangement which is optimal for most systems is for the HOE to act as a lens array, forming an image of the object on each detector element. The imaging requirement is a major factor of system design and a general equation relating system parameters is derived. The effects of imaging aberrations and diffraction effects are also considered.