中文摘要：

在满足气体检测要求的前提下，为了能够使气体检测仪器的小型化以及低功耗，设计了袖珍式红外瓦斯检测仪．以集光源、光路、红外探测器于一体的红外传感模块为核心，修正了传统的气体吸收理论，采用差分式气体吸收技术设计出一种具有低成本、低功耗、低检测下限、高信噪比的袖珍式非线性甲烷检测仪．集成后的仪器采用干电池单电源供电，工作时总电流在150mA以内、总功耗小于0．9W，检测仪的电路增益为43．3dB．实验中进行了单、双通道气体检测实验，采用新配气方法在甲炕爆炸限内进行双通道气体检测实验，得到低检测下限和高灵敏度测试实验，最低检测下限都能够达50ppm．与传统的壁挂式检测仪器相比，该仪器以手持式的形式完全可以满足检测有害气体的需求．

英文摘要：

On the base of meeting requirements of gas detection, a low cost, tow-powe, detection, high SNR（signal to noise ratio） pocket methane detector was designed, with the improvement on the original gas absorption theory, and the eore sensing module contains a mid-infrared light source, optical path, a mid-infrared dual detector. The device adopted dry batteries single power supply, and totally the supply current was less than 150 mA while the power consumption was less than 0.9 W, and the gain of the circuit was 43.3 dB. The single and dual channel detection experiments were carried out to contrast, and with the novel proportioning gas method both the sensitivity and the minimum detection limit under low concentration range could reach to 50 parts per million. Compared with the pre-existing wal-mounted devices, this device satisfies the requirement of detecting explosive gases in a more convenient handheld style.