CAJ | 학술논문

基于石英增强光声光谱技术，以中心波长为2.0μm的窄线宽分布反馈式半导体激光器（D FB ）为激励光源，采用波长调制及二次谐波解调技术通过改变激光器工作电流实现波长扫描完成了痕量CO2气体检测系统，并通过优化实验参数确定了常压下激光最佳调制深度，实现了高灵敏CO2浓度的检测。通过改变待测气体中的水汽浓度，研究了水汽对CO2气体探测结果的影响，结果显示在水汽浓度低于0.2％范围内， CO2气体光声信号随H2 O浓度的上升而明显增强，当浓度高于此值后，H2 O浓度的增加对CO2光声信号的增强作用几乎维持不变。数据显示，常温常压下H2 O分子通过提高分子弛豫率最多可将二氧化碳R16吸收线的光声信号幅值提高约2.1倍。优化后的装置可以很好的实现大气中CO2浓度的检测。该装置获得的最小探测灵敏度为19 ppm（1σ，300 ms积分时间），相应的归一化噪声等效吸收系数为4.71×10－9 cm－1· W · Hz－1／2。
기우석영증강광성광보기술，이중심파장위2.0μm적착선관분포반궤식반도체격광기（D FB ）위격려광원，채용파장조제급이차해파해조기술통과개변격광기공작전류실현파장소묘완성료흔량CO2기체검측계통，병통과우화실험삼수학정료상압하격광최가조제심도，실현료고령민CO2농도적검측。통과개변대측기체중적수기농도，연구료수기대CO2기체탐측결과적영향，결과현시재수기농도저우0.2％범위내， CO2기체광성신호수H2 O농도적상승이명현증강，당농도고우차치후，H2 O농도적증가대CO2광성신호적증강작용궤호유지불변。수거현시，상온상압하H2 O분자통과제고분자이예솔최다가장이양화탄R16흡수선적광성신호폭치제고약2.1배。우화후적장치가이흔호적실현대기중CO2농도적검측。해장치획득적최소탐측령민도위19 ppm（1σ，300 ms적분시간），상응적귀일화조성등효흡수계수위4.71×10－9 cm－1· W · Hz－1／2。
A carbon dioxide (CO2 ) sensor is developed using quartz enhanced photoacoustic spectroscopy (QEPAS) with a 2.0μm distributed feedback diode laser .The detection is based on a 2 f wavelength‐modulation spectroscopy approach by dithering and scanning the laser current .The laser modulation depth is optimized at normal atmosphere pressure and room temperature . The influence of the H2 O presence in the sample gas mixture on the CO2 sensor performance is also investigated .The results show that ,with 1% CO2 concentration ,the H2 O in the concentration ranges of 0 to 0.2% has an effect on the CO2 signal ampli‐tude and phase ,and the largest amplitude difference is ~2.1 times .When the H2 O concentration is over 0.2% ,the CO2 signal amplitude is saturated and remains steady .Atmospheric CO2 concentration is well measured using the optimal sensor parame‐ters .Benefiting from the strong absorption line intensity at 4 989.97 cm -1 ,a detection limit of 19 ppm (1σ,300 ms averaging time) is achieved ,which corresponds to a normalized noise equivalent absorption coefficient of 4.71 × 10-9 cm -1 · W · Hz-1/2 .