Abstract

Two-dimensional multiple beam splitters (MBSs) are needed in parallel processing, optical communication, optical interconnects, and applications alike. In this paper, we demonstrate the use of a liquid crystal television spatial light modulator (in phase-only modulation mode) to implement a real-time programmable MBS. The SLM we used has a pixel size of the order of 80 µm, and is capable of phase modulation at a continuous level. The structure of the MBS is first designed with a computer based on an adaptive iterative technique. The major physical features of the SLM, i.e., the pixel gap (or the dead zone), phase and amplitude variations of the SLMs grid structure, have also been considered in designing the MBS. The computer-designed MBS is then sent to the SLM, and another iteration based on the feedback in an optical architecture is conducted. The purpose of this step is to fine tune the design of the MBS to account for the detail pixel structure of the SLM. As a result, an optimum programmable MBS with high diffraction efficiency and high diffraction-spots uniformity can be made.

© 1991 Optical Society of America