Device for imposing a field tilt for approximating the inherent field curvature of a focusing element in a free space optical device

摘要

An optical beam path directing system has a field-flattening optically transmissive wedge installed in spatially dispersed beam paths upstream of the planar surface of a micro electro-mechanical switch (MEMS) or liquid crystal array. The parameters of the field-flattening wedge and its location in the diffracted beam paths are defined such that the wedge effectively rotates a "best fit' planar surface approximation of the curvilinear focal plane of a concave reflector into coplanar coincidence with the optical signal-receiving surface of the MEMS. As a result, loss variation is essentially flat and minimized across the optical signal transmission band.