Resolution limits of extrinsic Fabry-Perot interferometric displacement sensors utilizing wavelength scanning...

Area of Science:

• Optical Engineering
• Metrology
• Sensor Technology

Background:

• Extrinsic Fabry-Perot interferometers (EFPIs) are widely used for high-resolution displacement sensing.
• Understanding factors limiting EFPI resolution is crucial for optimizing sensor design and performance.
• Existing models may not fully capture the interplay between optical setup and interrogator parameters.

Purpose of the Study:

• To investigate and analytically model the factors limiting the resolution of EFPI-based displacement sensors.
• To develop a predictive model correlating EFPI resolution with optical setup and sensor interrogator parameters.
• To provide a framework for optimizing sensor design for specific resolution requirements.

Main Methods:

• Development of an analytical model for EFPI resolution based on optical parameters.
• Systematic analysis of the dependency of resolution on key setup and interrogator variables.
• Experimental validation of the analytical model using a prototype EFPI sensor.

Main Results:

• A comprehensive analytical model was established, predicting EFPI sensor resolution.
• The model accurately estimates resolution limits based on given optical configurations.
• Experimental results demonstrated a wide dynamic range (tens of microns to 5 mm) and high baseline resolution (14 pm).
• Experimental data showed strong agreement with the predictions of the developed analytical model.

Conclusions:

• The developed analytical model effectively predicts extrinsic Fabry-Perot interferometric sensor resolution.
• The model serves as a valuable tool for designing and optimizing EFPI sensors for desired performance.
• The study confirms the feasibility of achieving high resolution and a large dynamic range with EFPI technology.