Patent ID: 6023323
Filing Date: 2000-02-08
Classification: G01S

Abstract:
An optical device for measuring the distance to a remote object, the device comprising:a light source;a light receiver having a going light sensor and a returning light sensor;an electrical signal processing unit connected to said going and returning light sensors;a returning light guide way leading to said returning light sensor;an optical member for reflecting going light from said light source toward the remote object and for reflecting returning light from the remote object toward said returning light guide way along which said returning light travels to the returning light sensor;a reference optical track having one end directed to said light source and the other end directed to said going light sensor, so that a first part of the going light from said light source travels to said going light sensor through said reference optical track; anda light transmitting member having predetermined length and having a first end directed to said light source and a second end directed to said returning light sensor, so that a second part of the going light from said light source travels to said returning light sensor through said light transmitting member,wherein said electric signal processing unit computes a calculated length of said light transmitting member based on said first and second parts of the going light, and compares said calculated and predetermined lengths for effecting a temperature compensation of the measured distance to the object.