3 April 1989 Vibration Measurement By Closed-Loop Laser-Interferometry
Author Affiliations +
Proceedings Volume 1121, Interferometry '89; (1989) https://doi.org/10.1117/12.961311
Event: Interferometry '89, 1989, Warsaw, Poland
A laser interferometer with highly linear transfer characteristics for the undistorted measurement of mechanical vibrations is described. The linear transfer behavior is derived by a control loop which holds the optical phase difference within the interferometer on a constant value. As a phase-shifting element we use a linearized PZT actuator with integrated displacement sensor. With this interferometer harmonic and nonhannonic vibrations can be measured over 5 decades in the range of 1 Å to 25 μm. The frequency range extends from really DC to about 10 kHz (-3dB limiting frequency). Within the control loop we use primarily a proportional-integral controller with an integrated Wien-Robinson band-rejection filter which suppresses the resonance frequency of the PZT-actuator. This allows to increase the limiting frequency of the closed-loop interferometer by a factor 3 in contrast to a control loop without a rejection filter.
© (1989) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
W. Baetz, W. Baetz, W. Holzapfel, W. Holzapfel, "Vibration Measurement By Closed-Loop Laser-Interferometry", Proc. SPIE 1121, Interferometry '89, (3 April 1989); doi: 10.1117/12.961311; https://doi.org/10.1117/12.961311

Back to Top