Title: NIST Develops High-Resolution Fabry-Perot Interferometry for Advanced Metrology
NIST researchers are developing advanced Fabry-Perot interferometry techniques for high-precision displacement measurements. This method, which operates at extremely low temperatures, can measure displacements as small as one picometer while covering distances up to several centimeters. The technique provides a direct link to the SI unit of length, defined by the speed of light.
The technology is being adapted for various challenging applications. One project involves creating a “calculable capacitor” that realizes the electrical unit of capacitance, the Farad, by measuring the displacement of an electrode over 5-10 cm. Another project focuses on MEMS accelerometers, using high-bandwidth optical probing to realize acceleration measurements traceable to SI units. Cutting-edge technologies like frequency combs, narrow-linewidth lasers, and optical modulation techniques are being employed in these advanced measurement systems.
Source: https://www.nist.gov/programs-projects/fabry-perot-displacement-interferometry
Keywords: Interferometry, Metrology, Displacement, SI units, Frequency comb
