不同孔径时旋转曲面目标的散斑统计特性  

Statistical properties of dynamics speckles from rotating curvature objects in detecting aperture

作　　者：武颖丽[1] 吴振森[1] 

机构地区：[1]西安电子科技大学理学院,西安710071

出　　处：《科学通报》2011年第4期281-287,共7页Chinese Science Bulletin

基　　金：国家自然科学基金资助项目(60771038)

摘　　要：研究了高斯波束照射旋转曲面目标在菲涅耳衍射区产生的动态散斑强度起伏的统计特性,推导了探测孔径尺寸大小不同时,散斑强度起伏相关函数依赖于旋转目标曲率半径的关系.在不同探测孔径大小情况下,首先计算了平面目标与球目标的相关距离,接着给出了曲面目标以恒定角速度旋转时散斑强度起伏的相关时间随曲率半径的变化关系.最后,介绍了相关函数与探测时间之间的变化情况.结果表明,采用一定尺寸的探测孔径代替点探测时,曲面目标的散斑强度起伏的相关时间变得更容易测量.通过测量曲面目标的散斑强度起伏的相关时间可以非接触、非破坏性地测量旋转凸体的曲率半径.In order to explore the statistical properties of integrated intensity fluctuations of dynamic speckles produced in the Fresnel diffraction field from a rotating curvature object under illumination of a Gaussian beam,the dependence of the curvature radius of the rotating diffuse object on the correlation time of the speckle intensity fluctuation is especially expressed by taking into account the size of the detecting aperture.In different detecting aperture,the correlation distance of the speckle intensity fluctuation is calculated from plane and sphere surface,and the relation of time correlation length of the speckle intensity fluctuation with the radius of curvature is given when the curvature objects are rotating with constant angular velocity.Finally,the relation between the speckle intensity fluctuation and the time delay is discussed.Experimental results indicate that the relation of time correlation length of the speckle intensity fluctuation is more easily to survey when the detecting aperture with an appropriate size is replaced point.It becomes useful for determining the radius of curvature of the rotating diffuse object from measurements of the time correlation length of the speckle intensity fluctuation.

关 键 词：动态散斑 探测孔径 曲率半径 相关时间 

分 类 号：O436[机械工程—光学工程]