A Caltech Library Service

An optical vernier technique for in situ measurement of the length of long Fabry-Pérot cavities

Rakhmanov, M. and Evans, M. and Yamamoto, H. (1999) An optical vernier technique for in situ measurement of the length of long Fabry-Pérot cavities. Measurement Science and Technology, 10 (3). pp. 190-194. ISSN 0957-0233. doi:10.1088/0957-0233/10/3/013.

See Usage Policy.


Use this Persistent URL to link to this item:


We propose a method for in situ measurement of the length of kilometre-sized Fabry-Pérot cavities in laser gravitational wave detectors. The method is based on the vernier, which occurs naturally when the laser beam incident on the cavity has a sideband. By changing the length of the cavity over several wavelengths we obtain a set of carrier resonances alternating with sideband resonances. From the measurement of the separation between the carrier and a sideband resonance we determine the length of the cavity. We apply the technique to the measurement of the length of a Fabry-Pérot cavity in the Caltech 40m interferometer and discuss the accuracy of the technique.

Item Type:Article
Related URLs:
URLURL TypeDescription
Additional Information:Copyright © Institute of Physics and IOP Publishing Limited 1999. Received 19 May 1998, in final form 12 November 1998, accepted for publication 2 December 1998. Print publication: Issue 3 (March 1999). We are very grateful to G Hu for setting up the data acquisition for the experiment. We also thank S Whitcomb, A Lazzarini, J Camp and A Arodzero for discussions and their comments on the paper. This work is supported by the National Science Foundation of the USA under cooperative agreement PHY-9210038.
Subject Keywords:length measurement, vernier, Fabry-Pérot cavity, cavity length, Pound-Drever signal, LIGO
Issue or Number:3
Record Number:CaltechAUTHORS:RAKRAKmst99
Persistent URL:
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:10202
Deposited By: Archive Administrator
Deposited On:16 Apr 2008
Last Modified:08 Nov 2021 21:06

Repository Staff Only: item control page