Related Experiment Videos
Highly sensitive, wide dynamic range displacement sensor combining chromatic confocal system and phase-sensitive
Optics Express
|April 7, 2017
Summary
This study presents a novel displacement sensor achieving nanometer sensitivity. The innovative fiber-based system integrates chromatic confocal microscopy and phase-sensitive spectral optical coherence tomography for precise measurements.
Area of Science:
- Optical Metrology
- Nanotechnology
- Fiber Optics
Background:
- Accurate displacement sensing is crucial in various scientific and industrial fields.
- Existing sensors often face limitations in sensitivity, dynamic range, or complexity.
- Integrating multiple optical techniques offers potential for enhanced performance.
Purpose of the Study:
- To propose and validate a novel fiber-based displacement sensor.
- To achieve nanometer-level sensitivity within a submillimeter dynamic range.
- To demonstrate a robust method for displacement measurement using spectral multiplexing.
Main Methods:
- Integration of a chromatic confocal system and phase-sensitive spectral optical coherence tomography (PhS-SOCT) into a fiber-based Michelson interferometer.
- Spectral multiplexing to encode interference and confocal signals.
- Depth-resolved phase information for displacement evaluation and confocal signal for position-based unwrapping.
Main Results:
- A functional sensor system with a 0.102 mm dynamic range was successfully built and tested.
- Temperature-induced sample surface displacement was measured with high accuracy.
- Achieved a root mean square error of 3.9 nm for displacement measurements.
Conclusions:
- The proposed sensor effectively combines chromatic confocal and PhS-SOCT techniques for precise displacement sensing.
- The spectral multiplexing approach enables robust unwrapping of phase information.
- This technology offers a promising solution for high-sensitivity, moderate-range displacement measurements.