A laser sensor technique for measuring 3D surfaces based on the polarized heterodyne astigmatic principle

L. R. Qiu*, X. M. Ding

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

Abstract

A laser measurement technique based on polarized heterodyne astigmatic principle is proposed for high precision three-dimensional (3D) profile measurement. In the presented system, the defocus astigmatic signal coming from the polarized reflection of the detected 3D surface is used to determine the position of the surface. The work of tracing, scanning and processing of the detected 3D surface is performed by combining the system with an ultra precision laser coordinate measuring machine (CMM). Compared with the current heterodyne astigmatic measuring technique, a polarization incidence and Glan-Thompson prism (GP) is used in the novel polarized heterodyne astigmatic measuring method. The anti-interference ability of the optical sensing system is significantly improved. The undesired influence on the measurement results, caused by fluctuation of surrounding brightness, by the intensity disturbance of the laser source, and by the multi-reflection among optical elements, is effectively restrained. Experimental results show that the stability of the optical sensing system is better than 2%. The resolution of the system is better than 0.005μm.

Original languageEnglish
Pages (from-to)483-488
Number of pages6
JournalKey Engineering Materials
Volume295-296
DOIs
Publication statusPublished - 2005
Externally publishedYes

Keywords

  • 3D surface measurement
  • Defocus error signal
  • Polarization heterodyne astigmatism

Fingerprint

Dive into the research topics of 'A laser sensor technique for measuring 3D surfaces based on the polarized heterodyne astigmatic principle'. Together they form a unique fingerprint.

Cite this