Brightness conserving optical system for modifying beam symmetry

Abstract

An optical system for use in conjunction with a one or two dimensional array of high brightness sources where such sources are individually rotated by multiple reflective elements and in turn may be captured by beam filling optics and subsequently re-imaged by symmetric and asymmetric optics where the asymmetric optics preferentially image a single dimension while leaving the focus in the second dimension largely unaffected. In this manner and by properly selecting the spacing as well as the width of the line sources, and by properly designing the symmetric and asymmetric optics, the array of high brightness sources can be reformatted in a brightness conserving manner that allows the reformatted beam to simultaneously have an arbitrary ratio of image length to image width and arbitrary divergences in the respective dimensions. The multiple reflective elements provide the means of re-formatting between dimensions and in general consist of two reflecting surfaces that rotate sources such that the source axis initially parallel to the line passing through all sources is rotated to be perpendicular to the line passing through all sources. The system is particularly useful in reformatting beams from multiple sources of arrays of semiconductor lasers.