高斯光束的4F光学系统空间滤波效应模拟与实验验证

MATLAB Simulation of Fourier Transform of Gaussian Beam and the Spatial Filtering Effects Basing on 4F Optical Imaging System

以频谱的傅立叶变换与空间滤波理论为基础,对高斯光束经过4F光学系统的空间滤波后光强、相位调制进行了理论分析;利用MATLAB数学软件模拟了“光”字屏经过4F系统频谱面高通、低通滤波后形成的图像;自行设计微分屏,通过改变衍射光的相位实现了边缘增强的动态效果模拟,实验现象与以上模拟结果完全吻合。理论模拟可以生动、深入地揭示高斯光束在4F光学系统中傅立叶变换与空间滤波物理内涵,其模拟方法与效果展示可以为功能型滤波器的设计提供参考。

Based on the Fourier transform and spatial filtering theory of spectrum,the theoretical analysis of the light intensity and phase modulation of Gaussian beam after spatial filtering by 4F system is carried out.The MATLAB mathematics software is used to simulate the image formed by the high-pass and low-pass filtering of the“light”screen after 4F system.The differential screen was designed by ourselves,and the edge enhancement effect was realized by changing the phase of the diffracted light.The simulation results are in good agreement with the experimental data.Through theoretical simulation,the physical connotation of Gaussian beam Fourier transform and spatial filtering optical phenomena is vividly and deeply revealed,which lays a foundation for the design and effect demonstration of functional filters.