High-precision thermal expansion measurements using small Fabry-Perot etalons

Mark J. Davis; Joseph S. Hayden; Daniel L. Farber

doi:10.1117/12.734423

12 September 2007 High-precision thermal expansion measurements using small Fabry-Perot etalons

Mark J. Davis, Joseph S. Hayden, Daniel L. Farber

Proceedings Volume 6673, Time and Frequency Metrology; 66730R (2007) https://doi.org/10.1117/12.734423
Event: Optical Engineering + Applications, 2007, San Diego, California, United States

Abstract

Coefficient of thermal expansion (CTE) measurements using small Fabry-Perot etalons were conducted on high and low thermal expansion materials differing in CTE by a factor of nearly 400. The smallest detectable change in length was ~10^-12 m. The sample consisted of a mm-sized Fabry-Perot etalon equipped with spherical mirrors; the material-under-test served as the 2.5 mm-thick spacer between the mirrors. A heterodyne optical setup was used with one laser locked to an ~780 nm hyperfine line of Rb gas and the other locked to a resonance of the sample etalon; changes in the beat frequency between the two lasers as a function of temperature directly provided a CTE value. The measurement system was tested using the high-CTE SCHOTT optical glass N-KF9 (CTE = 9.5 ppm/K at 23 °C). Measurements conducted under reproducibility conditions using five identically-prepared N-KF9 etalons demonstrate a precision of 0.1 ppm/K; absolute values (accuracy) are within 2-sigma errors with those made using mechanical dilatometers with 100-mm long sample rods. Etalon-based CTE measurements were also made on a high-CTE (~10.5 ppm/K), proprietary glass-ceramic used for high peak-pressure electrical feedthroughs and revealed statistically significant differences among parts made under what were assumed to be identical conditions. Finally, CTE measurements were made on etalons constructed from SCHOTT's ultra-low CTE Zerodur^(R) glass-ceramic (CTE about -20 ppb/K at 50 °C for the material tested herein).

Citation Download Citation

Mark J. Davis, Joseph S. Hayden, and Daniel L. Farber "High-precision thermal expansion measurements using small Fabry-Perot etalons", Proc. SPIE 6673, Time and Frequency Metrology, 66730R (12 September 2007); https://doi.org/10.1117/12.734423

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available