Monolithic Structure-Optical Fiber Sensor with Temperature Compensation for Pressure Measurement

Area of Science:

• Optoelectronics and Photonics
• Materials Science
• Sensor Technology

Background:

• Traditional pressure sensors often face limitations in harsh environments.
• Developing robust, high-performance sensors for seepage pressure monitoring is crucial in various industrial applications.
• Existing fiber optic sensors may lack stability or require complex fabrication methods.

Purpose of the Study:

• To propose and demonstrate a novel all-fused-silica optical fiber pressure sensor.
• To develop a monolithic sensor structure using advanced laser welding techniques.
• To achieve accurate and stable seepage pressure measurement with temperature compensation.

Main Methods:

• Fabrication of a diaphragm-assisted Fabry-Perot interferometer (FPI) and fiber Bragg grating (FBG) using a femtosecond laser.
• Investigating laser heat conduction welding and deep penetration welding for monolithic sensor construction.
• Utilizing the FBG for environmental temperature compensation of FPI pressure readings.

Main Results:

• A monolithic, adhesive-free FPI pressure sensor was successfully developed via all-laser-welding.
• The sensor exhibited good linearity, excellent resolution, hysteresis, and long-term stability across different temperatures.
• Temperature compensation using FBG significantly minimized variations in seepage pressure responses.

Conclusions:

• The proposed all-fused-silica optical fiber sensor offers a robust and reliable solution for seepage pressure monitoring.
• The monolithic, laser-welded structure enhances sensor durability and performance.
• Effective temperature compensation ensures accurate measurements in varying environmental conditions.