High-speed electrooptical A/D converter

摘要

An electrooptical analog-to-digital (A/D) converter. A laser beam is coupled into a waveguide which has been fabricated on an electrooptical crystal such as a lithium niobate LiNbO3 crystal. Electrodes are placed relative to the waveguide to form an electrooptical prism and an analog signal is fed to the electrodes. A modulated laser beam passing through the electrooptical prism is deflected in the plane of the waveguide in proportion to the applied analog signal. The deflected beam is expanded in the y-direction by diffraction-spreading or by a beam-spreading lens and falls on a ribbon-fiber, coded detector array. The array effectively codes the analog signal, translating the position of the deflected beam into a coded digital word which is representative of the magnitude of the analog signal.