Rapid displacement sensor based on fitting scan

Abstract

A rapid displacement sensor with a varifocal lens based on a method of fitting scan is proposed for 3D surface profiling. The focal length of the varifocal lens can be adjusted by varying the driving current. By detecting the reflective power of the reflected laser, the displacement can be obtained. By integrating a LabVIEW program based on a Levenberg-Marquardt algorithm in this system, the measuring speed can be substantially improved. Finally, the 3D surface profile of a step-height sample was successfully scanned by this displacement sensor.