光栅光学小波滤波器

采用光学小波变换可以大大节省图像数据压缩的时间，实现图像数据的实时压缩，为图像的快速传输奠定基础.在典型的光学4f系统的谱面上加滤波片是实现光学小波变换的常用方法，该滤波片可以用胶片、全息图和光栅作为滤波片.但是，因为光栅参数与小波谱值的数学关系复杂，推导的难度较大，所以以往人们都采用胶片或全息图作为滤波片，这样做的精度并不高.作者研究的是在4f系统的谱面上加光栅作为滤波片来实现小波变换，推导了光栅参数与小波谱值的数学关系，为人们制作4f系统的滤波片提供了另一种新的参考.

Implementing optical wavelet filter by grating

The way using optical wavelet transformation will save the time of the image data compression, and the real-time compression of image data will be realized. This is the foundation for image speedy transmissing. Placing filter on the Fourier plane in a optical 4f system is an usual way to implement optical wavelet transformation. Film, holograph and grating can be used as the filter. Because the relationship between the grating parameters and the value of the wavelet spectrum is hard to get, people used film and holograph as the filter in the past, which could get a low precision. This article provides another reference for people to make the filter in 4f system. We will talk about using grating as the filter to implement optical wavelet transformation, the relationship between the grating parameters and the value of the wavelet spectrum will be given.