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Applied Optics

Applied Optics


  • Editor: Joseph N. Mait
  • Vol. 51, Iss. 26 — Sep. 10, 2012
  • pp: 6275–6281

Laser differential confocal radius measurement system

Ruoduan Sun, Lirong Qiu, Jiamiao Yang, and Weiqian Zhao  »View Author Affiliations

Applied Optics, Vol. 51, Issue 26, pp. 6275-6281 (2012)

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A laser differential confocal radius measurement system with high measurement accuracy is developed for optical manufacturing and metrology. The system uses the zero-crossing point of the differential confocal intensity curve to precisely identify the cat’s-eye and confocal positions and uses an interferometer to measure the distance between these two positions, thereby achieving a high-precision measurement for the radius of curvature. The coaxial measuring optical path reduces the Abbe error, and the air-bearing slider reduces the motion error. The error analysis indicates the theoretical accuracy of the system is up to 2 ppm, and the experiment shows that the system has high focusing sensitivity and is little affected by environmental fluctuations; the measuring repeatability is between 4 and 12 ppm.

© 2012 Optical Society of America

OCIS Codes
(120.0120) Instrumentation, measurement, and metrology : Instrumentation, measurement, and metrology
(180.1790) Microscopy : Confocal microscopy
(220.4840) Optical design and fabrication : Testing

ToC Category:
Instrumentation, Measurement, and Metrology

Original Manuscript: March 2, 2012
Revised Manuscript: August 8, 2012
Manuscript Accepted: August 8, 2012
Published: September 5, 2012

Ruoduan Sun, Lirong Qiu, Jiamiao Yang, and Weiqian Zhao, "Laser differential confocal radius measurement system," Appl. Opt. 51, 6275-6281 (2012)

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