Low-frequency harmonic vibration analysis with double-pulsed addition electronic speckle pattern interferometry
Abstract
We describe the control of a pulsed laser for measuring harmonic vibrations with a double-pulsed addition electronic speckle pattern interferometry. The basic requirement is to synchronize the laser pulses both to a known position of the object vibration cycle and to a charge coupled device camera. It is shown theoretically and experimentally that a t low object-vibration frequencies these synchronization requirements can cause instabilities in the laser output. A synchronization scheme to overcome these problems is described and experimental results presented at several low object-vibration frequencies. Addition fringe visibility is improved in real-time with an electronic filter.
- Publication:
-
Optical Engineering
- Pub Date:
- September 1996
- DOI:
- 10.1117/1.600869
- Bibcode:
- 1996OptEn..35.2641M