Parallel frequency analysis of non-stationary, temporal and spatial signals by means of optical Wigner distribution function

通过对Wigner分布函数的光学实现，发展了对时间和空间信号的局部谱进行并行、快速分析的方法。将所提出的方法应用于散斑照相中散斑图的分析。由于该项目的进展速度比最初的计划快，还研究了一种新的技术，用于设计信息处理的光学系统，使用维格纳分布函数的概念。主要研究结果如下：1.利用液晶空间光调制器作为输入器件，研制了一套光学信息处理系统，可由计算机或摄像机输出图像物体的维格纳分布函数。2.将研制的光学系统应用于散斑照相术中散斑图的分析，3.通过在所开发的信息处理系统的输入平面中引入单个声光调制器，4.基于Wigner分布函数同时描述信号在空间和空间频率上的行为的原理，一种设计Banyan、完全混洗和循环移位光学互连的相位滤波器的新方法。这些滤波器实际上是通过CGH来实现的。5.作为对所提出的光互连的进一步发展，我们开发了一种新型的用于光神经网络的紧凑互连和一种新型的光矩阵-矩阵乘法器，并对它们的性能进行了实验验证。

By means of optical realizations of Wigner distribution functions, methods were developed for parallel, rapid analysis of local spectra of temporal and spatial signals. The developed methods were applied to the analysis of specklegrams in the speckle photography. Because of the faster progress of the project than the initial plan, a new technique was also investigated for designing optical systems of information processing by using the concept of the Wigner distribution function. Main results are summarized in the following.1.By exploiting a liquid crystal spatiallight modulator as an input device, an optical information processing system was developed for generating the Wigner distribution function of image objects fed by a computer or a video camera.2.The developed optical system was applied to the analysis of specklegrams in speckle photography, and was shown to give an image of loacl displacement distribution of objects.3.By introducing a single acousto-optic modulator in the input plane of the developed information processing system, a new system was developed for generating the Wigner distribution functions of temporal signals.4.On the basis of the principle that the Wigner distribution function describes behaviors of signals in space and spatial frequency simultaneously, a new method for designing phase filters for Banyan, perfect shuffle, and cyclic shift optical interconnections. Those filters were actually realized by means of CGH.5.As a further development of the proposed optical interconnections, a new type of compact interconnections for optical neural networks and a new type of optical matrix-matrix multiplier were developed and their performance was verified experimentally.