High-Resolution, Fast-Response Optical Fiber Temperature Sensor With a Large Measurement Range Based on Fiber-Tip Alumina Fabry–Pérot Interferometer

We present an alumina-tip optical fiber Fabry–Pérot interferometric temperature sensor exhibiting high-temperature performance, rapid response, and high resolution. Fabricated by fusion splicing an alumina microdisk directly to a single-mode fiber, the sensor achieves robust, stable operation without complex fabrication processes or adhesives. Experimental evaluation confirms a measurement range extending to 1000°C, with sensitivity of 28.66 pm/°C, a resolution of 0.042°C, and a rapid response time of approximately 13 ms. Compared to state-of-the-art optical fiber FPI sensors, our alumina-tip sensor offers superior overall performance, effectively addressing critical demands for high-resolution, fast-response temperature measurement in extreme environments including aerospace, structural monitoring, metallurgy, and emerging flash-based thermal processing technologies.