Theoretical Analysis of Optically Addressed Spatial Light Modulator with Electromagnetic Driven Micromirror for Optical Information Processing

A novel optically addressed spatial light modulator for optical information processing is proposed. The modulator is integrated with micromirror, on which magnetic material is electroplated, photodiode and electric coil. A phtotocurrent will flow in the electric coil and the mirror supported by four cantilevers is actuated by the generated magnetic forces. This movable mirror is placed parallel to another fixed mirror, which structure is called a Fabry-Perot interferometer configuration. Theoretical analysis is performed to estimate the electromagnetic forces acting on the mirror and the displacement of the mirror. Numerical simulations by three-dimensional coupled magneto-structural finite element analysis are also performed, resulting in good agreement with theoretical results. In addition, it is shown that the proposed modulator is effective for pattern recognition.