摘要
高斯光束经位于成像系统共轭面的两个散射体(其中一个是恒速运动)后,在距像面为菲涅尔区的观测面上形成了串级动态散斑场.理论分析和实验测量结果均表明,这种动态散斑的空-时相关函数与一次散射形成的动态散斑相比,对散射体的运动十分敏感,但其时间相关长度与速度的倒数仍然保持线性关系.
After propagating through two diffusers (with one moving) placed on the two conjugate planes of an imaging system, a Gaussian beam is modulated randomly to form a dynamic cascade speckle field in the Fresnel zone with respect to the image plane. Both theoretical analysis and experimental results indicate that the linear dependence of the reciprocal of the time-correlation length on the velocity of the moving diffuser is still held in this case. Moreover, the time-space correlation function of the speckle field is more sensitive to the motion of the diffuser than that of single-scattered speckle.
出处
《光学学报》
EI
CAS
CSCD
北大核心
1992年第1期67-71,共5页
Acta Optica Sinica
基金
国家自然科学基金的资助
关键词
像面
调制
串级
散斑
空时相关
modulation of image speckles, dynamic cascade speckle, space-time correlation.
