相干光经过不透明散射介质的聚焦

Focusing Coherent Light through Opaque Scattering Media

由于散射介质的散射特性,入射光通过散射介质后相干性受到破坏形成散斑场,使得传统光学成像系统无法聚焦探测内部物体的信息。根据波前整形原理,通过反馈优化算法调控入射光束的相位,在目标位置处将散斑调制为聚焦光斑,光强增强。基于此方法,在实验上搭建实验平台,对空间光调制器(SLM)的每个像素加载系列等间隔相位,一次采集多幅散斑图像,应用局部最大优化算法实现对光束任意点聚焦,并提出了一种得到不同大小区域的均匀的聚焦光斑的新方法,为实现聚焦平面内的目标成像提供了新思路。

Due to the scattering characteristics of scattering medium,incident coherence light diffuses through the scattering medium and forms a volume speckle filed that has no coherence formation and the traditional optical imaging system cannot be focused to detect the internal information of the object.According to the principle of wavefront shaping,the speckle can be modulated into a bright focal spot by shaping the phase of the beam through the feedback optimization algorithm.Based on this method,we experimentally load series of equal interval phase for each pixel of spatial light modulator(SLM)and collect multiple speckle images to realize focusing of any point of the beam by local maximum optimization algorithm.Meanwhile,a new method for focusing different uniform areas is proposed,which provides a new way to achieve imaging the object of the focus plane.