强激光通过厚介质形成二级热像的数值研究  

Numerical Research of Second-order Hot Image in an Intense Laser Beam Through a Thick Medium Slab

作　　者：王友文[1] 袁丽芳[1] 游开明[1] 陈列尊[1] 陆世专[1] 戴志平[1] 凌晓辉[1] 

机构地区：[1]衡阳师范学院物理与电子信息科学系,湖南衡阳421002

出　　处：《衡阳师范学院学报》2013年第6期12-15,共4页Journal of Hengyang Normal University

基　　金：湖南省自然科学基金项目(11JJ3076);湖南省教育厅资助科研项目(12A020);湖南省"十二五"重点建设学科(光学)资助项目

摘　　要：以往二级热像研究主要针对薄介质情况,而实际介质具有一定的厚度,明确厚介质二级热像的规律,可避免它对元件造成损伤。运用基于快速傅里叶变换的光传输程序,数值研究了强激光经过厚介质二级热像形成的规律。结果表明:入射功率一定时,随着介质厚度的增加,二级热像光强单调增加;B积分一定时,随着介质厚度的增加,二级热像光强先单调增加,达到一极大值后,单调减小;入射光强与介质厚度一定,随着衍射物宽度增加,二级热像光强先单调增加达到一极大值后,单调减小,存在产生最强二级热像的散射物大小。Previous studies on second-order hot images are mainly concentrated on the thin nonlinear medium slab,while the realistic medium slab in high-power laser system may be of thickness.It can be helpful to avoid the damage of second-order hot images to the elements in high-power laser system to identify the formation of second-order hot images.The formation of second-order hot image is numerically investigated by using of simulation codes of light probation based on the Fast Furies Transformation.It is shown that,for given incident light power,the intensity of second-order hot image increases with the thickness of the nonlinear medium slab;for specified B integral,the intensity of the hot image monotonically increases at first,after reaching a maximal value,then decreases with the thickness of the nonlinear medium slab;for a specified incident light intensity and the thickness of the medium slab,with laagering of the obscuration,the intensity of second-order hot image monotonically increases at first,after reaching a maximal value,then decreases,indicating a most risky obscuration.

关 键 词：高功率激光 二级热像 小尺度自聚焦 厚Kerr介质 

分 类 号：O437.5[机械工程—光学工程]