Synthesis of a Holographic Beamformer Using a Separability Constraint

Abstract

In applications such as laser radar, active coherent imaging (possibly using phase retrieval), and optical data processing, it is often desired to uniformly illuminate a rectangular area that is in the far-field of the source. When using a laser with a Gaussian (TEMoo) intensity distribution as a source, an optical device is required to modify the near-field complex amplitude distribution of the beam such that its phase and intensity become uniform upon propagation to the far-field. We investigated the use of a holographic system to efficiently redistribute the beam energy into a near-field sinc(x) sinc(y) complex amplitude distribution. This holographic system was synthesized using the Gerchberg-Saxton algorithm.