Interferometric dynamic measurement: techniques based on high-speed imaging or a single photodetector.

Area of Science:

• Optical Metrology
• Noncontact Measurement
• Dynamic Deformation Analysis

Background:

• Optical interferometry is crucial for noncontact measurement of dynamic deformation in industry.
• Accurate real-time measurement requires satisfying the Nyquist sampling theorem.
• Existing techniques, high-speed cameras and single photodetectors, have limitations in temporal range and measurement points.

Purpose of the Study:

• To discuss advancements in camera-based and photodetector-based interferometry for dynamic deformation measurement.
• To explore methods for enhancing temporal measurement range and addressing single-point limitations.
• To highlight research efforts in improving interferometric techniques for industrial applications.

Main Methods:

• Camera-based interferometry: introduction of carrier, image processing, phase extraction algorithms, and multiwavelength techniques for extended temporal range.
• Photodetector-based interferometry: focus on single-point and multipoint laser Doppler vibrometers for measurements under extreme conditions.

Main Results:

• Analysis of image processing and phase extraction algorithms for camera-based systems.
• Demonstration of laser Doppler vibrometers for challenging measurement scenarios.
• Overview of strategies to overcome limitations in temporal measurement range and spatial coverage.

Conclusions:

• Significant research efforts are dedicated to enhancing optical interferometry for industrial dynamic deformation measurement.
• Both camera-based and photodetector-based techniques are evolving to meet stringent industrial requirements.
• Improvements aim to increase measurement speed, range, and applicability in diverse industrial settings.