Humidity and temperature sensor based on a Mach-Zehnder interferometer with a pokal taper and peanut taper

摘要

An optical fiber sensor for simultaneous measurement of humidity and temperature is proposed and investigated. The sensor is composed of a pokal taper and a peanut taper spliced at both ends of a single-mode fiber, respectively. In the experiment, the variations of the dip wavelength are used to measure the parameter sensing characteristics. The sensing area is coated with a concentration of 1 mg/ml graphene dispersion by using the optical driven deposition method. Experimental results show that the sensor has a good linear relationship with temperature and humidity. When the humidity measurement range is 30%RH similar to 70%RH, the sensitivities are 0.059 nm/%RH and 0.133 nm/%RH, respectively. When the temperature measurement range is 0 degrees C similar to 40 degrees C, the sensitivities are 0.254 nm/degrees C and 0.269 nm/degrees C, respectively. This sensor has the advantages of small size, low cost, and high response. (C) 2019 Optical Society of America