推帚式激光三维成像雷达关键技术研究

【作者】 陈伟军；

【导师】 杨华军；

【作者基本信息】 电子科技大学 ， 光学， 2010， 硕士

【摘要】 推帚式激光三维成像雷达经过近十几年来的快速发展,如今已经成为现代民用和军用目标探测中极具应用前景的三维成像方式。而在推帚式激光三维成像雷达系统中,大功率半导体激光阵列准直系统、激光阵列回波信号接收系统、半导体激光器功率与探测距离的关系、激光扫描轨迹十分重要,直接影响激光成像的效果和探测距离。本文主要针对推帚式激光三维成像雷达中的关键技术——大功率半导体激光阵列准直系统、激光阵列回波信号接收系统、半导体激光器功率的确定、激光扫描轨迹进行了深入的研究,并对准直光学系统和光学接收系统进行了优化设计和仿真。论文主要内容如下:1.对推帚式激光三维成像系统结构进行了分析,并研究了激光雷达测距原理,从分析微波雷达探测距离方程导出激光雷达探测距离方程,还深入研究了激光三维成像原理。2.以计算机仿真为平台,研究了无球差双曲面-平面柱透镜,对大功率半导体激光阵列准直器件优化设计,并分析了激光光源振动对激光发散角的影响。仿真结果表明,所设计系统具有良好的准直效果,理论上点光源在焦点50μm范围内振动时,准直光束发散角不超过1mrad。3.根据模式匹配原理,针对激光回波信号聚焦耦合入布拉格光纤进行优化设计。对于布拉格光纤,当不考虑纤芯外能量损失时,不同模式的激光最佳耦合效率不相同。4.根据对激光探测距离方程分析,选定激光工作波长λ= 1550nm,得出激光探测距离与激光发射功率的关系。并对激光扫描轨迹进行分析建模,得出成像的最小像素。更多还原

【Abstract】 Three-Dimensional line imaging laser radar has been experienced a rapid development in recent years; it has a wide range of three-dimensional imaging application in both military and civil use. While in the three-dimensional line imaging laser radar system, the high-power semiconductor laser array alignment system, laser array echo wave signal receiving system, the power of semiconductor laser and laser scanning track will have a direct impact on the imaging effect and detection distance.Some in-depth research such as the high-power semiconductor laser array alignment system, the power of semiconductor laser and laser scanning track are discussed in this paper and also conduct some optimization design and stimulation in optical collimation system and optical receive system.The main contents involved in this dissertation are as follows:1.Analyzing the system structure of three-dimensional line imaging laser radar system and the principal of the laser radar ranging. From the microwave radar range equation, and then elicit the equation of three-dimensional line imaging laser radar system.2.Using the computer stimulation to analyze the Spherical aberration-free double-surface - flat cylindrical lens when apply to the design of high-power semiconductor laser array alignment system and the influence of the laser divergence angle caused by the laser source vibration. The stimulation results show that such design has a good collimation effect, when the light spot vibrate within the focus range of 50μm , the divergence angle cannot beyond the 1mrad .3.According to the model matching theory, make some optimization design of Bragg fiber coupling of focused echo signal. As to Bragg fiber, when ignore the energy loss outside the core, the coupling efficiency are different under different models.4.Based on the laser radar detection equation, selected the laser wavelength 1550nm, and then obtain the relationship between laser detection distance and laser power. Through modeling the laser scanning track, get the minimum imaging pixel.更多还原