LIGHT RECEIVING MODULE FOR ENCODER AND OPTICAL ENCODER USING THE MODULE

摘要

PROBLEM TO BE SOLVED: To provide a light receiving module for encoder for easily judging an abnormality of a part such as a measuring light source, and an optical encoder using this module.;SOLUTION: This optical encoder is composed of the measuring light source A, a modulating plate B, and the light receiving module C. A current signal outputted from photodiodes 11 to 14 for receiving the measuring light passing through the modulating plate is converted into a voltage signal by amplifiers 21 to 24. A signal processing part 3 measures position information on the modulating plate B on the basis of the voltage signal from the amplifiers 21 to 24, and outputs the position information via a position information output part 4. A light quantity monitoring part 5 forms an adding voltage signal by adding the voltage signal from the amplifiers 21 to 24 by an adding part 5a, and judges an abnormality of the part such as the measuring light source A by comparing the adding voltage signal with comparison reference voltage in a light quantity judging part 5b, and outputs judgement result via an output part 6.;COPYRIGHT: (C)2004,JPO