Optical system phase error compensator

摘要

A method for compensating for phase errors in an optical data processing system for performing a Fourier transformation analysis of a data source. The aberrations of the system are holographically recorded by passing an object beam through the system and the optical data source in a direction opposite to that of the DC read beam used in the transformation analysis. The object beam and a reference beam derived from a common coherent light source are generated by the system and directed to an optical memory wherein the interference pattern between the object and reference beam is recorded. The data source is analyzed by providing a read beam incident the optical memory along a path in the reverse direction of the reference beam. In such manner, a reconstruction beam emanating from the hologram is directed back through the data source to display the Fourier transform of the data in the data source. The reconstruction beam thus serves to automatically compensate for phase errors introduced into the system by thickness variations of the data source as well as from the lenses in the system.