Analysis of a micro-optical light modulator

A light modulator with microlens arrays in a confocal arrangement and with various filters in the common focal plane of the arrays, which are translated with the help of piezoelectric actuators, is proposed. The theoretical analysis deals with the influence of the lens arrays on the performance of the modulator. The system is investigated for spatially incoherent beams. It is shown that the configuration is suited for efficient modulation of radiation emitted by multimode fibers. A choice of the proper focal length. of the microlens arrays and lens pitch d results in a good transmission efficiency(above 90%) combined with a large number of possible switching states. (C) 1997 Optical Society of America.