OPO—CARS光谱技术与微量气体浓度的测量

本文利用相干反斯克斯拉曼光谱（CARS）技术，根据在低浓度时极化率的共振项对非共振项的调制与被测气体的浓度有关，提出了通过测量调制度求出微量气体浓度的方法，建立了共振极化率的调制度与被测气体浓度，温度之间关系，验证了数量关系式的正确性，其结果理论值与实验值在低浓度范围内的偏差不超过4．5％，并实测了酒精火焰中不同位置处的CO浓度，讨论了气体温度等因素对测量结果的影响。

The Study on Measurement of Low Concentration Gas Using OPO CARS Techniques

According to the relation,which between species concentration and modulated depth of resonant susceptibility to non resonant susceptibility in low concentration,a method is presented to measure the low concentration species in other species.A formula is given between modulated depth of resonant susceptibility,gas concentration and temperature,which its correction is verified by experiment.The CO concentration of different position in alcohol frame is measured.The error between theoretical value and experimental value is lowered to 4.5 %.Further,Influence of temperature to testing result is discussed.