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Working equation for a Fabry-Perot cavity based optical pressure standard
Published
Author(s)
Yuanchao Yang, Patrick Egan, Tom Rubin
Abstract
From basics of Fabry-Perot (FP) resonator and roundtrip phase, a complete working equation for a FP cavity based optical pressure standard (OPS) is derived and presented which includes corrections of reflection phase-shift, diffraction and pressure-induced distortion. The correction from diffraction, i.e. Gouy phase, is negligible. To operate an OPS as a primary standard, two unknown parameters, i.e. mirror dispersion coefficient epsilon_alpha and pressure distortion coefficient d_m, in the working equation should be determined independently. Methods to determine epsilon_alpha and d_m are described and applied to an OPS developed at the National Institute of Metrology (NIM), China. Thermodynamic effect observed in the determination of d_m is also discussed.
Proceedings Title
2023 CCM & IMEKO International Conference on Pressure and Vacuum Metrology
Yang, Y.
, Egan, P.
and Rubin, T.
(2024),
Working equation for a Fabry-Perot cavity based optical pressure standard, 2023 CCM & IMEKO International Conference on Pressure and Vacuum Metrology, Rockville, MD, US, [online], https://doi.org/10.21014/tc16-2023.09, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=933955
(Accessed October 8, 2025)