Laser interferometer and its measuring method

Abstract

Abstract PURPOSE: To constitute a small-size and solid interferometer, by using a semiconductor laser as the laser light source. CONSTITUTION: A laser interferometer is composed of laser light source 10 consisting of a semiconductor laser, thermostat 12 which holds laser light source 10 at a prescribed temperature, half mirror 22 which divides the laser beam being incident through collimator 14 from light source 10 and projects this divided laser beam to moving corner cube 20 of a moving reflector, which moves vertically together with fixed corner cube 16 of a fixed reflector and measurer 18 which are fixed and arranged, and synthesizes reflection lights again, photodetector 24 which detects the interference fringe from half mirror 22, and measuring circuit 26 which obtains displacement of measurer 18 on the basis of the output of photodetector 24. In case of measurement of the height of the object to be measured, handle 66 is operated to move measuring point 28 vertically, and values x 1 and x 2 for two masters having known height l 1 and l 2 are read, and next, (x) for the object to be measured is read, thus obtaining height l x accurately by operating [(x-x 1 )(l 2 - l 1 )/(x 2 -x 1 )]+l 1 . COPYRIGHT: (C)1981,JPO&Japio

Inventors

• 👤 Motonobu Bando
• 👤 Satoshi Omori

Bibliographic Details