Capacitance micrometry is a technique for measuring the relative displacement of two surfaces. As the spacing between the two surfaces changes so the capacitance changes. This short paper is a summary of recent measurements made to characterize and understand the linearity and scale factor.
Thomas R. Hicks,
Paul D. Atherton,
"Linearity of capacitance micrometry", Proc. SPIE 2865, Actuator Technology and Applications, (20 November 1996); doi: 10.1117/12.259036; https://doi.org/10.1117/12.259036