中文说明：主要是基于mtlab的程序，窗函数法设计一个数字带通FIR滤波器，用于信号特征提取、信号消噪，利用最小二乘算法实现对三维平面的拟合，一些自适应信号处理的算法，计算十字叉丝的在不同距离的衍射图像。
English Description：
Is mainly based on MTLAB procedures, the window function method to design a digital FIR bandpass filter, used for signal feature extraction, signal denoising, the 3D plane fitting based on least square algorithm, some adaptive signal processing algorithm, calculation crosshair in different distance diffraction image.