AUTOMATIC EXTINCTION RATIO MEASURING EQUIPMENT

摘要

PROBLEM TO BE SOLVED: To measure the extinction ratio of laser light accurately in a short time by delivering an output light, impinging on a rotating polarizer, to a photoelectric converter and subjecting an electric signal, amplified through a plurality of amplifiers, to A/D conversion thereby measuring the extinction ratio. ;SOLUTION: A polarizer 4 is fixed to a rotating disc 3 in the center thereof and a light to be measured is projected thereto. Output light from the polarizer 4 is received by a photodiode 5 which produces an electric signal subjected to photoelectric conversion. The electric signal is passed through amplifiers 7, 8 having different gain and subjected to A/D conversion before being processed by a signal processing computer 13.;COPYRIGHT: (C)1997,JPO