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Published on: August 5, 2009
Time-resolved vibration measurement with temporal speckle pattern interferometry.
Jochen Kauffmann1, Hans J Tiziani
1Institut für Technische Optik, Universität Stuttgart, Germany. jkauffmann@smt.zeiss.de
Applied Optics
|August 24, 2006
Summary
Temporal speckle pattern interferometry (TSPI) measures rough surface displacement using pointwise evaluation. This optical technique enables accurate, time-resolved vibration measurements, even for large displacements.
Area of Science:
- Optical Measurement Techniques
- Surface Metrology
- Vibration Analysis
Background:
- Rough technical surfaces require precise displacement measurement.
- Existing methods may face limitations with decorrelation and large displacements.
Purpose of the Study:
- To develop an inexpensive fiber-optical point sensor based on TSPI.
- To investigate the theoretical accuracy of TSPI for vibration measurement.
- To validate TSPI performance against a high-precision vibrometer.
Main Methods:
- Temporal speckle pattern interferometry (TSPI) tracks time-dependent speckle modulation.
- Pointwise evaluation of speckle modulation without reference to neighboring pixels.
- Development of a fiber-optical point sensor concept.
Main Results:
- TSPI enables independent point sensing for displacement measurement.
- Incremental phase tracking allows for time-resolved mechanical vibration analysis.
- The developed sensor concept shows good agreement with high-precision vibrometer measurements for loudspeaker membrane vibrations.
Conclusions:
- TSPI is a viable technique for measuring displacement and vibrations on rough surfaces.
- The developed fiber-optical sensor offers a cost-effective solution for precise measurements.
- TSPI's ability to handle large displacements and reduce decorrelation effects is significant.
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