Measuring pulsed picometer-displacement vibrations by optical interferometry
- 1 August 1976
- journal article
- research article
- Published by AIP Publishing in Applied Physics Letters
- Vol. 29 (3) , 183-185
- https://doi.org/10.1063/1.89017
Abstract
Optical interferometers are very sensitive if they operate at the point halfway between the peak and minimum of detected intensity. By introducing a 90° phase shift between orthogonal polarizations in the reference beam, the interferometer signals due to each polarization are in quadrature; squaring and summing the signals effectively stabilizes the operating point of the interferometer at the high‐sensitivity point, independent of the large low‐frequency variations in optical‐path difference caused by ambient disturbances. This method has been used to make stable (±0.5 dB) measurements of 2.5‐MHz ultrasound pulses of 1‐pm displacement.Keywords
This publication has 2 references indexed in Scilit:
- Some Aspects of Fringe Counting in Laser InterferometersIEEE Transactions on Instrumentation and Measurement, 1966
- Wavelength or Length Measurement by Reversible Fringe Counting*Journal of the Optical Society of America, 1953