Swing arm optical coordinate-measuring machine: High precision measuring ground aspheric surfaces using a laser triangulation probe

Yuhao Wang, Peng Su, Robert E. Parks, Chang Jin Oh, James H. Burge

Research output: Contribution to journalArticle

18 Scopus citations


The swing arm optical coordinate-measuring machine (SOC), a profilometer with a distance measuring interferometric sensor for in situ measurement of the topography of aspheric surfaces, has shown a precision rivaling the full aperture interferometric test. To further increase optical manufacturing efficiency, we enhance the SOC with an optical laser triangulation sensor for measuring test surfaces in their ground state before polishing. The calibrated sensor has good linearity and is insensitive to the angular variations of the surfaces under testing. Sensor working parameters such as sensor tip location, projection beam angle, and measurement direction are calibrated and incorporated in the SOC data reduction software to relate the sensor readout with the test surface sag. Experimental results show that the SOC with the triangulation sensor can measure aspheric ground surfaces with an accuracy of 100 nm rms or better.

Original languageEnglish (US)
Article number073603
JournalOptical Engineering
Issue number7
StatePublished - Jul 1 2012



  • Aspherics
  • Ground surface metrology
  • Laser triangulation sensor
  • Optical testing
  • Profilometry
  • Swing arm profilometer

ASJC Scopus subject areas

  • Atomic and Molecular Physics, and Optics
  • Engineering(all)

Cite this