Vibration-compensated interferometer for surface metrology

Chunyu Zhao, James H. Burge

Research output: Contribution to journalArticle

25 Scopus citations

Abstract

An advanced interferometer was built for surface metrology in environments with severe vibration. This instrument uses active control to compensate for effects of vibration to allow surface measurement with high-resolution phase-shifting interferometry. A digital signal processor and high-speed phase control from an electro-optic modulator allows phase measurements at 4000 Hz. These measurements are fed back into a real-time servo in the digital signal processor that provides a vibration-corrected phase ramp for the surface measurements taken at video rates. Unlike fringe locking, which compensates vibration to keep the phase constant, we show a true phase servo that allows the phase to be stabilized while it is ramped, enabling surface measurements using phase-shifting interferometry that requires multiple images with controlled phase shifts.

Original languageEnglish (US)
Pages (from-to)6215-6222
Number of pages8
JournalApplied optics
Volume40
Issue number34
DOIs
StatePublished - Dec 1 2001

ASJC Scopus subject areas

  • Atomic and Molecular Physics, and Optics
  • Engineering (miscellaneous)
  • Electrical and Electronic Engineering

Fingerprint Dive into the research topics of 'Vibration-compensated interferometer for surface metrology'. Together they form a unique fingerprint.

  • Cite this