基于红外差分检测的甲烷气体传感器

鉴于红外吸收法检测甲烷气体浓度时，误差的补偿是提高检测精度的核心。通常采用各种差分吸收技术来进行误差的补偿，减少各种干扰。基于红外差分检测原理，设计一种双波长差分甲烷传感器。利用旋转滤光盘控制滤波和光的通过，使测量光和参考光分时通过光路，实现了单光源单光路单探测器结构，消除了光源功率波动、光路损耗以及探测器的不稳定带来的误差，提高了检测精度。实验表明，在0～6%浓度范围内，该传感器最大相对误差小于1%。

Methane gas sensor based on infrared difference detection

In infrared absorption detection of methane, the key to improve detecting precision is to compensate the errors. Various differential absorption techniques are usually adopted to compensate the errors, which reduce different kinds of interferences. On the basis of infrared differential detection, a dual-wavelength difference methane sensor was designed. A rotating filter was used to control the filtering and passing through of the light, which made the detecting light and reference light pass through the optical path in a time-sharing way. The sensor structure of single-source single-light-path and single-detector was implemented, eliminating the errors caused by the source power fluctuations, the light-path loss and the detector instability. The experiments show that the sensor has high measurement precision: in the concentration range of 0~6%, the maximum relative error is less than 1%.