基于马赫-泽德干涉仪级联结构的高灵敏度光纤温度传感器  

Sensitivity-enhanced Optical Fiber Temperature Sensor Based on the Cascaded Lyot Filter and Mach-Zehnder Interferometer

作　　者：王梓丞 田凯迪 匡崇葳 赵玉欣[1] 张相军[1] WANG Zicheng;TIAN Kaidi;KUANG Chongwei;ZHAO Yuxin;ZHANG Xiangjun(School of Instrumentation Science and Engineering,Harbin Institute of Technology,Harbin 150001,CHN)

机构地区：[1]哈尔滨工业大学仪器科学与工程学院,哈尔滨150001

出　　处：《半导体光电》2024年第5期759-766,共8页Semiconductor Optoelectronics

摘　　要：光纤温度传感器由于其结构的小型化和抗电磁干扰能力强受到了研究者的广泛关注,但目前部分传感器灵敏度无法满足实际需求。针对这一问题,提出了一种基于Lyot滤波器和马赫-泽德干涉仪级联的高灵敏度光纤温度传感器。马赫-泽德干涉仪由两个级联的气泡型凸锥组成,因其全保偏光纤结构具有较好的稳定性。同时,作为传感干涉仪的Lyot滤波器是通过在两个线偏振器之间以45°角熔接一段保偏光纤制成。通过调整Lyot滤波器中传感部分保偏光纤的长度,使其自由光谱范围接近马赫-泽德干涉仪,从而产生游标效应增强级联传感器的灵敏度。实验结果表明,Lyot滤波器的灵敏度为-1.4 nm/℃,级联传感器的灵敏度提高到-28.3 nm/℃,灵敏度放大倍数为20.2。所提出的光纤温度传感器偏振稳定性强、制作简单、灵敏度高,能够满足工业领域中的高精度应用需求。Optical fiber temperature sensors gave attracted significant interest owing to their compact structure and resistance to electromagnetic interference.Nevertheless,it is imperative to enhance the detection sensitivity to adequately fulfill the existing requirements.This study proposes and demonstrates a sensitivity-enhanced optical fiber temperature sensor using the cascaded Lyot filter and Mach-Zehnder interferometer(MZI),based on the Vernier effect.The MZI has two consecutive bubble-type upper tapers and is employed as a reference interferometer,owing to the exceptional stability of its totally polarization-maintaining fiber(PMF)construction.A Lyot filter is created by fusion splicing a segment of PMF at a 45°angle between two linear polarizers,functioning as a sensing interferometer.The sensitivity of the cascaded sensor is improved through the Vernier effect,which is produced when the length of the sensing PMF in the Lyot filter is modified to closely match the free spectral range(FSR)of the MZI.Experimental results reveal the sensitivity of the Lyot filter is-1.4 nm/℃,while the cascaded sensor achieves an increased sensitivity of-28.3 nm/℃,with a sensitivity amplification factor of 20.2.The proposed PMF sensor structure leverages the controllable polarization characteristics to enhance system performance,effectively addressing the issue of detection errors that arise from the fluctuating polarization state of the optical signal being transmitted throughout the sensitivity test.This proposed optical fiber temperature sensor,with a robust polarization stability,simple fabrication,and high sensitivity,is suitable for high-precision industrial applications.

关 键 词：光纤传感器 游标效应 马赫-泽德干涉仪 Lyot滤波器 温度 

分 类 号：TP212.11[自动化与计算机技术—检测技术与自动化装置]