CAJ | 학술논문

基于中红外光谱吸收技术，利用一氧化碳（CO ）气体分子在4.6μm处的基频吸收带，采用新脉冲的红外光源和双通道的热释电探测器，研制了一种CO浓度检测系统。该系统主要由脉冲调制式宽带热光源、开放式椭球聚光镜/气室、双通道探测器、主控及信号处理模块构成。通过优化开放式椭球聚光镜/气室，气体吸收光程达到40 cm ，探测器输出电信号的幅度增加约为原来的2～3倍。因此，采用椭球聚光镜后，将在一定程度上提高系统的信噪比从而改善系统的性能指标。利用配备的CO气体样品，研究了该系统对CO气体的传感特性。实验结果显示，该系统的最小检测下限为10 ppm ，在该浓度点的测量误差约为14％；在20～25000 ppm范围内的测量误差小于7.8％；对0 ppm气体样品的连续50分钟测量结果的最大偏差约为3 ppm ，标准差约为0.18 ppm。同基于量子级联激光器和分布反馈激光器的CO检测系统相比，该系统具有性价比高、光路结构简单等优势，从而在煤矿、环保等场合下的CO检测方面具有较好应用前景。
기우중홍외광보흡수기술，이용일양화탄（CO ）기체분자재4.6μm처적기빈흡수대，채용신맥충적홍외광원화쌍통도적열석전탐측기，연제료일충CO농도검측계통。해계통주요유맥충조제식관대열광원、개방식타구취광경/기실、쌍통도탐측기、주공급신호처리모괴구성。통과우화개방식타구취광경/기실，기체흡수광정체도40 cm ，탐측기수출전신호적폭도증가약위원래적2～3배。인차，채용타구취광경후，장재일정정도상제고계통적신조비종이개선계통적성능지표。이용배비적CO기체양품，연구료해계통대CO기체적전감특성。실험결과현시，해계통적최소검측하한위10 ppm ，재해농도점적측량오차약위14％；재20～25000 ppm범위내적측량오차소우7.8％；대0 ppm기체양품적련속50분종측량결과적최대편차약위3 ppm ，표준차약위0.18 ppm。동기우양자급련격광기화분포반궤격광기적CO검측계통상비，해계통구유성개비고、광로결구간단등우세，종이재매광、배보등장합하적CO검측방면구유교호응용전경。
Based on infrared spectral absorption technique ,a carbon monoxide (CO) detection system was developed using the fundamental absorption band at the wavelength of 4.6 μm of CO molecule and adopting pulse-modulated wideband incandescence and dual-channel detector .The detection system consists of pulse-modulated wideband incandescence ,open ellipsoid light-collec-tor gas-cell ,dual-channel detector ,main-control and signal-processing module .By optimizing open ellipsoid light-collector gas-cell ,the optical path of the gas absorption reaches 40 cm ,and the amplitude of the electrical signal from the detector is 2 to 3 times larger than the original signal .Therefore ,by using the ellipsoidal condenser ,the signal-to-noise ratio of the system will be to some extent increased to improve performance of the system .With the prepared standard CO gas sample ,sensing characteris-tics on CO gas were investigated .Experimental results reveal that ,the limit of detection (LOD) is about 10 ppm ;the relative er-ror at the LOD point is less than 14% ,and that is less than 7.8% within the low concentration range of 20~180 ppm ;the maxi-mum absolute error of 50 min long-term measurement concentration on the 0 ppm gas sample is about 3 ppm ,and the standard deviation is as small as 0.18 ppm .Compared with the CO detection systems utilizing quantum cascaded lasers (QCLs) and dis-tributed feedback lasers (DFBLs) ,the proposed sensor shows potential applications in CO detection under the circumstances of coal-mine and environmental protection ,by virtue of high performance-cost ratio ,simple optical-path structure ,etc .