Dynamic phase evaluation in sparse-sampled temporal speckle pattern sequence.

Area of Science:

• Optical Metrology
• Experimental Mechanics
• Vibration Analysis

Background:

• Modern manufacturing demands advanced inspection techniques for vibration characterization and dynamic testing.
• Speckle interferometry is a key technique for dynamic measurement due to its accuracy and whole-field capabilities.
• Traditional methods require dense temporal sampling for phase retrieval, limiting applications.

Purpose of the Study:

• To propose a novel method for phase evaluation of sparse-sampled speckle patterns.
• To enable accurate dynamic measurement with sampling rates below two points per temporal cycle.
• To overcome limitations of traditional dense-sampling requirements in speckle interferometry.

Main Methods:

• Development of a new phase evaluation algorithm for sparse speckle data.
• Utilizing electronic/digital speckle pattern interferometry (ESPI/DSPI).
• Conducting dynamic experiments with a high-speed camera for validation.

Main Results:

• The proposed method effectively retrieves wrapped phase information from sparse-sampled speckle patterns.
• Demonstrated feasibility for complicated phase retrieval scenarios.
• Successful application in dynamic experiments validating the technique's performance.

Conclusions:

• The developed method significantly enhances the applicability of speckle interferometry for dynamic testing.
• It allows for accurate vibration characterization with reduced data acquisition requirements.
• This advancement supports stringent inspection needs in modern manufacturing.