Calibration of Piezoelectric Driven Mirrors for Laser Resonators
AEROSPACE CORP EL SEGUNDO CA LAB OPERATIONS
Pagination or Media Count:
A new technique for measuring small displacements of piezoelectric driven mirrors in which is employed an acousto-optic modulator and optical heterodyning has been applied to the calibration of piezoelectric driven mirror systems for laser resonator cavities. In this technique, a phase detector is used to measure the phase change when a mirror, driven by the piezoelectric translator, moves. Measurements obtained by means of this technique have been compared with measurements obtained with the traditional interferometer methods and have proven to be more precise. The increased precision was attributed to higher signal to noise ratios typically obtained with frequency modulated, relative to amplitude modulated, systems where intensity fluctuations exist in the system. The increased signal to noise ratio is advantageous when, as frequency increases, the output voltage from the driving power amplifier falls off. For a given amplifier, frequency response data of the piezoelectric driver mirror combination can be determined at higher frequencies. In the case at hand, the frequency has been extended from 15 to 40 kHz.
- Lasers and Masers
- Acoustooptic and Optoacoustic Devices