A Hot-Polymer Fiber Fabry-Perot Interferometer Anemometer for Sensing Airflow

Area of Science:

• Optical sensing technologies
• Fiber optic instrumentation
• Anemometry

Background:

• Traditional anemometers face limitations in certain applications.
• Fiber Fabry-Perot interferometers (FFPIs) offer compact and sensitive sensing platforms.
• Developing novel sensing materials and configurations is crucial for advanced instrumentation.

Purpose of the Study:

• To propose and demonstrate the first hot-polymer fiber Fabry-Perot interferometer (HPFFPI) anemometer.
• To investigate the feasibility of using a heated polymer microcavity for airflow sensing.
• To evaluate the performance of the HPFFPI anemometer in terms of sensitivity and resolution.

Main Methods:

• Fabrication of an ultracompact fiber Fabry-Perot microcavity using a single-mode fiber endface and UV-cured polymer.
• Heating the polymer microcavity using a chip resistor to achieve a steady-state temperature above the ambient environment.
• Measuring airflow by detecting the wavelength shift of optical spectra caused by the cooling effect of the air on the hot polymer.
• Experimental evaluation of HPFFPI anemometers with varying cavity lengths and heating power.

Main Results:

• The HPFFPI anemometer demonstrated effective airflow measurement capabilities.
• A high sensitivity of 1.139 nm/(m/s) was achieved.
• A resolution of 0.0088 m/s was obtained for airflow within the 0–2.54 m/s range.
• Optimal performance was observed with a 10 μm cavity length and 0.402 W heating power.

Conclusions:

• The proposed HPFFPI is a viable and effective solution for airflow sensing.
• The device exhibits high sensitivity and resolution, making it suitable for precise air velocity measurements.
• This technology opens new avenues for compact and efficient optical anemometry.