激光散斑引起的波前探测误差及误差消除研究  

Wave-front detective error produced by laser speckle and error elimination

作　　者：刘丽丽 邓玉福[1] 封文江[1] 崔崧[1] 

机构地区：[1]沈阳师范大学物理科学与技术学院,沈阳110034

出　　处：《沈阳师范大学学报（自然科学版）》2015年第1期72-75,共4页Journal of Shenyang Normal University:Natural Science Edition

基　　金：辽宁省科技厅科学技术计划项目(20092069)

摘　　要：激光具有较高的能量且单色性较好,因此被广为应用在弱光波前探测系统中。但激光的强相干性产生的像面散斑会造成CCD面阵上的光强无规律分布,导致波前重构质心算法的错误,进而降低波前像差探测的精度。分析了激光散斑降低波前探测精度的原因,并尝试用旋转散射体、多模光纤耦合及随机位相板等多种组合方法消除激光散斑,提升波前探测精度。评估几种方法对光强、光均匀性及消除散斑的效果进行对比分析、优化设计激光为光源的波前探测消散斑系统。最后利用随机位相板与多模光纤耦合的方法有效消除激光散斑,并进行消散斑前后的波前探测。该消散斑系统可有效消除激光散斑并提升波前探测精度,大幅提升了激光光源在自适应光学领域的应用性。Laser was commonly used in dim light wave-front detective system because of its high energy andmonochromaticity property. Due to the nature of high coherence, the intensity dispersion will be disordered when focusedon the CCD panel, causing centroid algorithm error. Hence the accuracy of detecting will be decreased consequently. Inthis paper, the reason for decreased wave-front detective accuracy was analyzed. Based on the analysis, several methodsand compounded one, such as rotation of a light diffuser, random phase plate and multimode coupled fiber were used toeliminate the laser speckle and improve wave-front detective quality. The comparision was made among them andconsequently a laser speckle eliminating system was optimized： a random phase plate cooperated with a multi modecoupled fiber was finally used to decrease the bad effect of laser speckle. Wave-front detective system was used to detectsame wave-front with the speckle eliminating system and without it. It was clearly demonstrated that the optimizedsystem could effectively remove the laser speckle and increase the wave-front detective accuracy. The applied range oflaser in adaptive optics system was enlarged.

关 键 词：波前探测 夏克哈特曼波前传感器 激光散斑 自适应光学 

分 类 号：O439[机械工程—光学工程]