多通道单脉冲激光能量变化监测方法

Multichannel Single-Pulse Laser Energy Monitoring Methodology

提出一种多通道单脉冲激光能量变化的监测方法,用于实时监测脉冲激光的状态。首先采用多合一光纤束,对待测激光进行取样;再经过消色差透镜将光纤合束端面成像到CMOS图像传感器的感光面,通过软件获取光斑图像并提取不同光斑的灰度值,以表征脉冲激光能量;最后根据各待测激光总能量大小对灰度值进行标定,即可实现不同位置处激光能量变化的同时在线监测。利用该方法,对全高程全天时大气探测激光雷达系统中1064,532,589 nm激光以及脉冲染料激光器中自发辐射(ASE)荧光的单脉冲能量变化进行了长时间同时在线监测,得到了激光雷达运行过程中这4束光单脉冲能量的变化情况,并根据监测结果计算了倍频晶体的倍频效率、脉冲染料激光器的转换效率及ASE比例系数。该研究为需要对多路激光单脉冲能量变化进行同时在线监测的光电系统提供了一种有效的解决方法。

This paper proposes a multichannel single-pulse laser energy monitoring methodology to realize real-time monitoring of the laser pulse energy at different laser transmitter positions. The sample laser pulse is coupled with an all-in-one optical fiber bundle and imaged onto a CMOS photosensitive surface through an achromatic lens. A software is used to enable real-time identification and calculation of the grayscale values in the CMOS image for each laser pulse. The grayscale value is adjusted to obtain the laser pulse energy. Using the proposed methodology, a long-term and simultaneous monitoring of single-pulse energy of 1064, 532, and 589 nm lasers as well as amplified spontaneous emission(ASE) fluorescence in the 1--110 km diurnal atmospheric lidar can be achieved. The efficiency of the secondary harmonic generation, conversion efficiency of the pulsed dye laser, and ASE ratio can be obtained based on the measurements of the laser pulse energy. This methodology can be advantageous for the laser system, which monitors the multichannel single-pulse energy.