Excellent repeatability, all-sapphire Fabry Perot optical Pressure sensor based on wet etching and direct bonding for
Optics Express
|July 16, 2021
Summary
This study introduces a robust sapphire extrinsic Fabry-Perot interferometer (EFPI) sensor for accurate dynamic pressure measurement in harsh conditions. It offers reliable performance across wide temperature and pressure ranges, ideal for demanding industrial applications.
Area of Science:
- Optical Sensing
- Materials Science
- Mechanical Engineering
Background:
- Harsh environments pose challenges for repeatable dynamic pressure measurement.
- Existing sensors may lack durability or accuracy under extreme conditions.
- Sapphire offers excellent material properties for high-temperature and high-pressure applications.
Purpose of the Study:
- To develop an all-sapphire extrinsic Fabry-Perot interferometer (EFPI) sensor.
- To enable repeatable dynamic pressure measurement in harsh environments.
- To calibrate pressure measurements using integrated temperature sensing.
Main Methods:
- Fabrication of the EFPI sensor using wet etching and direct bonding techniques.
- Utilizing temperature measurements from the EFPI for pressure calibration.
- Employing a cross-correlation function (CCF) algorithm for optical interrogation.
Main Results:
- The EFPI sensor demonstrates applicability in temperatures from 25°C to 800°C.
- The sensor operates within a pressure range of 0MPa to 5MPa.
- Achieved pressure sensitivity of 355.8nm/MPa and temperature sensitivity of 1.64nm/°C.
Conclusions:
- The all-sapphire EFPI sensor successfully addresses the challenge of repeatable dynamic pressure measurement in harsh environments.
- The sensor's compact size (8x8mm) and robust structure make it suitable for demanding applications.
- Significant potential for pressure monitoring in systems like jet engines and industrial gas turbines.
