高分辨率光纤法珀传感器解调系统设计

Design of high resolution fiber Fabry-Perot sensor demodulation system

光纤法珀传感器的腔长测量精度取决于解调系统的分辨率,现有的解调系统的分辨率多大于10 nm,难以实现10 nm以内腔长变化的测量。针对该问题,提出了以7 450像元数的线阵图像传感器为基础搭建解调系统,通过硬件设计与软件算法提高特征信号质量,完成腔长数据提取,实现了一种高分辨率光纤法珀传感器解调系统。实验结果表明,该系统在0~20μm的腔长测量范围内,实现了2.7 nm的光学分辨率,精度达到0.013 5%FS。

Measurement precision of cavity length of fiber Fabry-Perot sensors depends on the resolution of the demodulation system.Existing demodulation systems often have a resolution of greater than 10nm,which is difficult to measure changes in cavity length beyond 10 nm.Aiming at this issue,a demodulation system based on 7450 pixel linear array image sensor is proposed,which improves the quality of feature signals through hardware design and software algorithms,completes cavity length data extraction,and implementes a high-resolution fiber Fabry-Perot sensor demodulation system.The experimental results show that the system achieves an optical resolution of 2.7 nm and an precision of 0.0135%FS within the cavity length measurement range of 0~20μm.