Optical modulator

摘要

The invention relates to an optical modulator in which an interim light beam is split, by means of a double-refracting (birefringent) crystal, into an ordinary beam and into an extraordinary beam, polarised perpendicular thereto. According to the invention, two optically identical double-refracting crystals are arranged in one plane one behind the other in such a manner that their optical axes run with mirror-imaged symmetry relative to a vertical imaginary plane between these two. In this plane, a chopper is arranged, by means of which either the ordinary or the extraordinary beam can be fed to the second crystal, so that an ordinary or an extraordinary light beam, polarised perpendicular thereto, leaves the second crystal coaxially to the light beam entering the first crystal. <IMAGE>