ELECTROOPTICAL SCANNING DEVICE

摘要

An electrooptical scanning device for deflection of an optical beam of light across an image plane. The device comprises a body of electrooptical crystal material and a periodic array of parallel, spaced electrodes associated with one surface of the body. A light beam entering the crystal body is caused to interact with electric fields established at the one surface by step applied voltages to the electrode array that influence the deflection of the light beam at the moment of total internal reflection at the one surface. By varying the magnitude of the applied voltages across the electrodes, a corresponding approximation of a desired phase retardation can be produced along the phase front of the light beam. The phase retardation across the light beam can be designed to produce a linear phase front angled beam or can be designed to produce a curvalinear phase front forming a focused spot at the image plane. With the changing of the magnitude of the applied voltages across the electrode array, the beam or spot may be made to move about or scan across the image plane.