High-Sensitivity Liquid Level Sensor Based on Seven Core Fiber
A liquid level sensor based on a single mode-peanut-seven core-peanut-single mode fiber structure is developed.The sensor uses the"peanut structure"as a fiber coupler to improve the coupling efficiency of the single-mode fiber and seven-core fiber.The first fiber"peanut structure"is used to excite the cladding mode,and the second fiber"peanut structure"couples the cladding mode with the core mode to produce interference.Because a phase difference between the cladding and core-based modes appears as they transmit through the seven-core fiber,when the liquid level of the environmental solution changes,the phase difference changes,eventually changing the transmission spectrum.In this study,the liquid level and temperature response characteristics of the sensors with seven-core fiber lengths of 24,28,and 32 mm were experimentally studied.The experimental results show that with the increase of the liquid level,the transmission spectrum of the sensor shows a blue shift.The liquid level sensitivities of the three sensors are-0.4069,-0.2739,and-0.1653 nm/mm,and their liquid level measurement ranges are 24,28,and 32 mm,respectively.In the water temperature range of 35‒90℃,the transmission spectrum of the sensor shows a red shift with an increase in temperature.The temperature sensitivities of the three sensors are 0.0885,0.0740,and 0.0879 nm/℃.The experiment shows that the sensor has the characteristics of high sensitivity,low cost,and simple fabrication,indicating that it has a good application prospect in the petrochemical industry and other fields.
NETL
NSTL
万方数据
