Share Email Print

Proceedings Paper

Wavelength-tracking capabilities of a Fabry-Perot cavity
Author(s): Jack A Stone; Alois Stejskal
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

We have characterized the accuracy of atmospheric wavelength tracking based on a laser servolocked to a simple Fabry-Perot cavity. The motivations are (1) to explore a method for air refractive index measurement and (2) to determine the stability and accuracy of these cavities when employed as a length reference, with potential application to absolute distance interferometry, air-wavelength stabilized lasers, or similar applications. The Fabry-Perot cavity consists of mirrors optically contacted to an ultra-low-expansion spacer with the interior of the cavity open along its length to the surrounding air. Changes in laser frequency are monitored to determine changes in the refractive index of the gas in the cavity. We have studied limitations of this technique that arise from humidity effects, thermal distortion, and (for absolute refractive index measurements where the cavity must be evacuated) pressure-induced distortions. Comparing results from two cavities with very different lengths gives us a very sensitive probe of errors associated with end effects, and pressure-induced distortions can be measured by filling the cavity with helium, whose index of refraction is believed to be well known from ab initio calculations. The uncertainty of refractive index measurements can be greatly reduced when these sources of error are measured and corrected.

Paper Details

Date Published: 20 November 2003
PDF: 12 pages
Proc. SPIE 5190, Recent Developments in Traceable Dimensional Measurements II, (20 November 2003); doi: 10.1117/12.506313
Show Author Affiliations
Jack A Stone, National Institute of Standards and Technology (United States)
Alois Stejskal, National Institute of Standards and Technology (United States)

Published in SPIE Proceedings Vol. 5190:
Recent Developments in Traceable Dimensional Measurements II
Jennifer E. Decker; Nicholas Brown, Editor(s)

© SPIE. Terms of Use
Back to Top