Abstract

A highly accurate method of optical path-length measurement is introduced by use of a scanning heterodyne optical interferometer with no moving parts. The instrument has demonstrated the potential to measure optical path length at angstrom resolution over continuous thickness in the micrometer range. This optical path length can be used to calculate the thickness of any material if the refractive index is known or to measure the refractive index of the material if the thickness is known. The instrument uses a single acousto-optic device in an in-line ultra-stable reflective geometry to implement rapid scanning in the microsecond domain for thickness measurements of the test medium.

© 2003 Optical Society of America

High-speed path-length scanning with a multiple-pass cavity delay line

Pei-Lin Hsiung, Xingde Li, Christian Chudoba, Ingmar Hartl, Tony H. Ko, and James G. Fujimoto
Appl. Opt. 42(4) 640-648 (2003)

Common-path interferometer for frequency-domain optical coherence tomography

Andrei B. Vakhtin, Daniel J. Kane, William R. Wood, and Kristen A. Peterson
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Circularly polarized optical heterodyne interferometer for optical activity measurement of a quartz crystal

Chien Chou, Wen-Chuan Kuo, and Chien-Yuan Han
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Scanning laser differential-heterodyne interferometer for flying-height measurement

Bryan Kok Ann Ngoi, Krishnan Venkatakrishnan, and Bo Tan
Appl. Opt. 39(4) 578-584 (2000)

Submicrosecond speed optical coherence tomography system design and analysis by use of acousto-optics

Nabeel A. Riza and Zahid Yaqoob
Appl. Opt. 42(16) 3018-3026 (2003)