非线性拉曼激光雷达测量CO_2气体的研究

Study on the Nonlinear Raman Lidar Monitoring the CO_2 Gas

提出了利用气体的受激拉曼散射(SRS)效应激光雷达光源来探测大气中的CO2气体的新方法,设计出探测大气中CO2气体含量的非线性拉曼增益激光雷达,用Nd:YAG激光器(1064nm)的三倍频光(354·7nm)通过分别装有CO2气体和N2气体的拉曼管,分别得到CO2气体和N2气体的受激拉曼散射的一阶斯托克斯线(S1),并用S1线作为雷达的种子发射光源。通过实验得到拉曼管中的气压与S1能量的变化关系,对其优化条件和物理机制进行了分析。该实验方法已经成功测出了大气中CO2气体的回波电压信号。

It is a new skill to use SRS rays as emitting waves for the lidar monitoring CO2 gas, and the nonlinear Raman lidar based on the SRS process was devised. The third harmonic Nd.YAG laser wave （354. 7 nm） was injected into the Raman ceils filled with higher pressure gases, CO2 and N2. The first Stokes （S1） line 371.66 nm （CO2） and 386. 7 nm （N2） were generated by stimulated Raman scattering. The variable S1 energy was measured by changing the gas pressure in the Raman cell and the Nd：YAG laser system output energy. The optimum pressures of the CO2 and N2 in the Raman cell were achieved. Moreover, the principles of this physical process were put forward. This skill has been applied to the lidar for monitoring the CO2 gas.