【摘要】 研究和设计了探测大气CO2浓度的Raman激光雷达,其发射机采用Nd:YAG激光的三倍频 354．7 nm作为工作波长,发射的单脉冲能量60 mJ,重复频率20 Hz;接收机采用了光电倍增管(量子效率 25％)和光子计数器(计数速率200 MHz),探测CO2的Raman散射371．66 nm(频移1285 cm-1)信号, 采用组合滤光片来抑制强的354．7 nm Mie-Rayleigh后向散射和氧气Raman后向散射375．4 nm对信号的严重干扰。主要采取排除法,检验其他波段的辐射是否被截止,实验证明回波主要是371．66 nm辐射。O2的干扰大约为CO2信号的1％。更多还原

【Abstract】 The design and experiment of a Raman lidar system for measurement of atmospheric CO2 are presented. 354.7 nm third harmonic of Nd:YAG laser is transmitted with 60 mJ pulse energy and repetition rate of 20 Hz. Receiver employed photomultiplier tube with quantum efficiency of 25% and 200 MHz photon counter, and it detects Raman backscat tering signal 371.66 nm (shift 1285 cm-1) from CO2. Combinatorial filter is used to reject interference presented by 354.7 nm intense Mie-Rayleigh backscattering and 375.4 nm Raman backscattering from O2 . Other wavelength radiation was excluded to enter photomultiplier tub. The interference from O2 is approximately 1% of the anticipated CO2 signal.更多还原