Laser line interferometric sensor for multipoint velocity and distance measurements with camera based 3D calibrations

Optical, non-contact velocity and position measurement techniques offer great opportunities of in-process monitoring for instance in turning lathes and microfluidics. This work presents a novel laser line interferometric sensor, which enables simultaneous multipoint velocity and distance measurements. The sensor system is developed with cylindrical lens based measurement volume expansion and line camera based full field detection. Meanwhile, a matrix camera based calibration method is presented for an essential 3D evaluation of fringe spacings in the measurement volume. Experimental results show that the sensor allows synchronous multipoint velocity and distance measurements with a submicron distance uncertainty and a relative velocity uncertainty of 10−3 .