【摘要】 中红外为分子的基频吸收带,利用可调谐二极管吸收光谱(TDLAS)技术,扫描气体的单根吸收谱线,可以对温室气体进行高灵敏度探测。介绍了利用2704nm波段激光器结合直接吸收的方法对温室气体进行探测的小型化光谱仪的研制。利用数字信号处理器(DSP)对吸收信号进行采集处理,并根据环境温度值和海拔高度对气体吸收浓度进行校正,同时对激光器波长进行锁定,保证了探测精度,最后对结果数据进行存储。系统采用电池供电,响应时间为1.6s,检测限为5×10-7,实验对系统进行了长时间测试,验证了系统的稳定性和可行性。更多还原

【Abstract】 Mid-infrared spectrum region is the fundamental absorption band of molecules.Tunable diode laser absorption spectroscopy(TDLAS)technology can be applied to detect greenhouse gas sensitively by scanning a single molecular absorption line.A miniaturized system based on the combination of direct absorption method and a 2704 nm band laser is presented,which is utilized to monitor carbon dioxide.Also,the digital signal processor(DSP)data acquisition system can be applied to acquire and process the absorption signal,as well as to revise the concentration according to the environment temperature and altitude.In order to eliminate the shift of wavelength and ensure the detection accuracy,the wavelength locking module is used and finally a SD card is used for data storage.The system is powered by a battery,the response time is 1.6 s and the detection limit is 5×10-7.It takes a long time to test the system,which ensures its stability and feasibility.更多还原