It is well known that nonlinear self - focusing effect is one of the important factors to limit icf laser energy and worsen beam quality 实践表明，非线性自聚焦效应是限制icf驱动器激光输出能量及破坏光束质量的主要因素之一。
In chapter 2 , we discuss the optics self - focusing in beam propagation . the early research was based on the scalar approximation and paraxial approximation 早期的自聚焦研究是在考虑了傍轴近似和标量场近似的前提下得到的。
Self - focusing is one of the fundamental problems in nonlinear optics . it has always been a hot topic since the naissance of nonlinear optics 自聚焦是非线性光学中的一个基本物理问题，自非线性光学诞生以来它一直是一个热门课题。
The lensless fourier hologram of object by using selfoc lens is obtained , and the clear image is numerical reconstructed 通过自聚焦透镜对物体成像，记录并再现了物体的全息图，得到了较满意的再现像，为进一步利用光纤传像奠定了基础。
In this high power laser system , nonlinear self - focusing effect especially the small - scale self - focusing is the main limiting factor 在这种高功率激光系统中，非线性自聚焦效应是其主要的限制因素，其中尤其以小尺度自聚焦效应最为严重。
On the basis of contrast maximization autofocusing algorithm ( cma ) , a method based on minimum entropy criteria ( mec ) for sar imagery autofocusing is proposed 在对比度最大化自聚焦算法的基础上，提出了基于图像熵最小准则的自聚焦算法。
The system ' s output power has been limited and its cost of operation has been enhanced because of filament destroy caused by small - scale self - focusing 由于小尺度自聚焦会造成系统的成丝破坏，因而限制系统的输出功率，导致系统运行成本增高。
This paper discusses the subaperture correlation method and the phase gradient autofocus algorithm . raw data processing or simulation is made to analyze these algorithms 本文讨论了子孔径相关法及相位梯度自聚焦算法，进行了实际数据处理或仿真分析。
So , the two main effects ( small - scale self - focusing and " hot image " ) relate to the 3rd order nonlinear effect have been studied in this work 因此，在本论文中，我们系统地对与介质三阶非线性有关的两种现象(小尺度自聚焦效应和“热像”现象)进行了研究。
A type of small - sized interferometer is reported , which makes use of the coupling of optical fiber and gradient index lens ( grin ) to form parallel light beams 摘要介绍一种超小型光纤导光干涉仪，它利用光纤和自聚焦透镜的耦合来形成平行光路，利用半反和全反光学膜片分光。
