4kHz重复频率卫星激光测距系统及其应用

分析了上海天文台皮秒激光器系统在不同重复频率下的输出功率、输出波形等性能,实现了重复频率为4 kHz、功率为3 W、波长为532 nm的激光稳定输出。建立了4 kHz重复频率卫星激光测距系统,实现了4 kHz重复频率卫星测距,其测量数据量和标准点数据精度比1 kHz重复频率的分别提高了约2.62倍和1.62倍,提升了卫星观测性能。采用Lomb算法获得了Ajisai卫星自转频率(平均值为0.4234 Hz)以及自转频率准确度(0.0054 Hz),与1 kHz激光观测系统相比,4 kHz重复频率卫星激光测距系统的卫星自转测定精度显著提升。     

PASCO实验平台的设计性应用思路及其尝试

本文利用PASCO平台的传感器及数据采集设备对传统单缝衍射实验设备进行改造,使单缝衍射的光强分布等不易观察的物理量得到感官表现,并能通过软件进行定量分析,具有良好的实验教学效果.     

全固态双向加压调Q激光器及放大技术研究

报道了一台激光二极管侧面泵浦Nd:YAG双向加压式电光调Q全固态纳秒激光器。采用结构简单的平-平腔设计,当重复频率为500 Hz时,得到了脉宽为5～20ns的可调输出,当脉冲宽度为6ns时,获得了平均输出功率为2.31W、中心波长为1064 nm的基模光,光束发散角为2.1 mrad,M2≤1.2,单脉冲能量稳定性高于1.16%(均方根)。采用两种不同的双通放大方式对调Q光进行放大,分别获得了功率为18.7 W和24.4 W的脉冲输出,单脉冲能量抖动低于2.16%和1.87%。     

Space debris laser ranging with a 60 W single-frequency slab nanosecond green laser at 200 Hz

Space debris laser ranging was achieved with a 60 W, 200 Hz, 532 nm nanosecond slab, single-frequency green laser at the Shanghai Astronomical Observatory's 60 cm satellite laser ranging system. There were 174 passes of space debris measured in 2017, with the minimum radar cross section(RCS) being 0.25 m~2 and the highest ranging precision up to 13.6 cm. The RCS of space debris measured with the farthest distances in 174 passes was analyzed. The results show that the farthest measurement distance(R) and RCS(S) were fitted to R = 1388.159 S0.24312, indicating that this laser can measure the distance of 1388.159 km at an RCS of 1 m~2,which is very helpful to surveillance and research on low-Earth-orbit space debris.