基于紧聚焦方式的阵列光束相干合成特性分析  

Analysis of coherent combination characteristics of beam array via tight focusing

作　　者：钟哲强[1] 母杰[2,3,4] 王逍 张彬[1] Zhong Zhe-Qiang;Mu Jie;Wang Xiao;Zhang Bin(College of Electronics and Information Engineering,Sichuan University,Chengdu 610065,China;Laser Fusion Research Center,China Academy of Engineering Physics,Mianyang 621900,China;Science and Technology on Plasma Physics Laboratory,Mianyang 621900,China;Collaborative Innovation Center of IFSA(CICIFSA,,Shanghai Jiao Tong University,Shanghai 200240,China)

机构地区：[1]四川大学电子信息学院,成都610065 [2]中国工程物理研究院激光聚变研究中心,绵阳621900 [3]等离子体物理重点实验室,绵阳621900 [4]上海交通大学IFSA协同创新中心,上海200240

出　　处：《物理学报》2020年第9期166-173,共8页Acta Physica Sinica

基　　金：国家自然科学基金青年科学基金(批准号:61905167);国家重大专项应用基础项目(批准号:JG2017149,JG2019299,JG2019292);中国博士后科学基金(批准号:2018M643463)资助的课题.

摘　　要：为获得高功率、波长量级尺寸的聚焦光斑,提出利用紧聚焦方式实现阵列光束相干合成的新方案.通过建立阵列光束经紧聚焦方式相干合成的物理模型,分析了阵列光束的排布方式、偏振态、束宽、间距和紧聚焦系统数值孔径等参数对合成光束特性的影响及规律.结果表明,阵列光束经紧聚焦方式合束时,线偏振及圆偏振阵列光束均能获得较好的合成效果,径向偏振阵列光束次之,而角向偏振阵列光束则不能有效地合成.通过优化阵列光束的排布方式、束宽和间距,以及合理选择紧聚焦系统的数值孔径,能在保持较好光束质量和较高合成效率的前提下获得能量集中度高的焦斑.In order to obtain focal spot with high power and spot size comparable to wavelength scale, a novel approach to achieving the coherent combination of beam array by tightly focusing is proposed. The physical model of coherent beam combination of beam array via tightly focusing is built up by the use of the vector diffraction integral. Therefore the influences of beam configuration, polarization state, beam width, beam interval and numerical aperture of the tight focusing system on the characteristics of the combined beam are discussed in detail. The results indicate that the coherent combination effect of beam array with linear and circular polarization via tight focusing is the first best, and that with the radial polarization is the second best but that with the azimuthal polarization is the worst. The beam array of linear and circular polarization with rectangle configuration can be tightly focused onto center point, and the beam array with hexagon is also focused onto center point but with lower efficiency. In addition, by enlarging the beam width and the beam interval to a certain extent, the combination efficiency can be increased. By optimizing the beam configuration,beam width and interval, and selecting rational numerical aperture of the tightly focusing geometry, the focal spot with high energy concentration can be obtained with high beam quality and combination efficiency.

关 键 词：紧聚焦 阵列光束 相干合成 数值孔径 

分 类 号：O436[机械工程—光学工程] TN24[理学—光学]