Optical fiber temperature sensor based on Fabry-Perot coating interference

In order to develop a miniature fiber-optic temperature sensor with simple structure, low cost and mass production, the principle of optical coating interference-based temperature sensor was analyzed. The coating formula of temperature sensing probe was designed by TFCalc formula designing software using ZrO2 and Al2O3 materials. The thin film was deposited on the tip of multimode fiber by using electron-beam evaporation in Nanguang ZZS1100-8/G box type vacuum coating machine. The measurement system of coating interference-based temperature sensor was interrogated. The experimental result shows that the wavelength shift of the fiber-optic temperature sensor is linear in the range of 200-600℃, and the correlation coefficient was calculated to be 99.7%, the sensitivity of temperature is 8.3710-6/℃. The temperature sensor based on Fabry-Perot interference is suitable for mass production with stable performance, accurate point measurement, narrow installation position or higher application requirements for integrated sensor.