摘要
入射到标准具上的光斑强度分布影响标准具透过率曲线的形状,进而影响风速反演。将激光入射进积分球后在腔壁上发生漫反射,出射激光光斑变均匀,从而使标准具的透过率曲线更准确。同时出射激光脉冲的宽度在时域上变宽,提高了探测的信噪比,扫描得到的标准具的透过率曲线也更稳定。同样的道理,锁定通道的锁定过程也由于这两点改变而更精确。积分球的这两点特性用于355 nm瑞利测风激光雷达系统中将大大提高探测的稳定性和信噪比。将激光通过积分球后扫描透过率曲线,在风速大小为±100 m/s的范围内计算得到的风速误差最大值为0.061 m/s,平均值为0.054 m/s。
The intensity distribution of the illumination on the interferometer affects obviously on its transmission curves and then influences on the inversion of wind velocity. However, the incident laser into the integrating sphere is diffuse in the cavity wall and the output laser flare becomes uniform, thereby making the transmittance curve more precise. Meanwhile the pulse width of the output laser is increased in the time domain and this will improve the signal to noise ratio of the detection, thereby making the transmittance curve more stable. For the same reason, the process of the frequency locking is more precise. These two properties of integrating sphere, which are used for 355 nm Rayleigh wind lidar system will greatly enhance the stability of detection and the signal to noise ratio. The transmission curves will be scanned through the integrating sphere. The results show an accuracy of 0.061 m/s for the maximum error and 0.054 m/s for the average wind velocity of less than 100 m/s.
出处
《红外与激光工程》
EI
CSCD
北大核心
2014年第11期3547-3554,共8页
Infrared and Laser Engineering
基金
国家自然科学基金(41174130
41227804
41304123)
中国科学技术大学青年创新基金(WK2080000048)
关键词
积分球
光斑
脉冲展宽
激光雷达
integrating sphere
illumination
pulse stretching
lidar
