LASER INTERFEROMETER FOR POSITION MEASUREMENT AND CONTROL

A modular two-frequency laser interferometer system has been developed for position measurement and control. The two-frequency design of the interferometer, based on a highly stable Zeeman laser head provides great measurement range, stability and low sensitivity to noise. It has been used for single and double axis measurements. The accuracy and reliability has been tested by means of displacement measurements on an MVM 7500 milling machine in a range of 5 m and the data has been compared with those measured by a Hewlett-Packard Laser Measurement System. The high resolution version of the laser interferometer has a resolution of 0.01 mum. With the two axis system preliminary measurements were made on the Ultraturn turntable where it was used as position transducer in the control loop of the axle-drive.