Miniature fiber-optic high temperature sensor based on a hybrid structured Fabry-Perot interferometer

Area of Science:

• Optoelectronics
• Fiber Optics
• Sensor Technology

Background:

• High-temperature sensing is critical in various industrial applications.
• Existing fiber-optic sensors face limitations in extreme temperature environments.
• Miniaturized sensors offer advantages in space-constrained or harsh conditions.

Purpose of the Study:

• To propose and demonstrate a miniature fiber-optic sensor for high-temperature measurements.
• To investigate the performance of a novel Fabry-Perot (FP) interferometric sensor design.
• To analyze the sensor's response to thermal variations up to 1000°C.

Main Methods:

• Fabrication of a sensor head using fusion splicing of hollow-core fiber, single-mode fiber, and photonic crystal fiber to create dual FP cavities.
• Measurement of reflection spectra at elevated temperatures.
• Analysis of spectral data in the spatial frequency domain to determine temperature effects.

Main Results:

• The sensor successfully operated at temperatures up to 1000°C with 50°C increments.
• The thermal-optic effect was found to be more significant than thermal expansion in the cavity material.
• The sensor demonstrated a clear and measurable response to temperature changes.

Conclusions:

• The miniature FP interferometric fiber-optic sensor is a viable solution for high-temperature sensing applications.
• The sensor design exhibits robustness and sensitivity in extreme thermal conditions.
• Further development could lead to widespread adoption in industries requiring precise high-temperature monitoring.