fresnel.m

菲涅耳衍射的程序

%菲涅耳积分卷积方法
function [f1,dx1,dy1,x1,y1] = fresnel(f0,M,N,dx0,dy0,z,lambda)
k=2*pi/lambda;
du=1./(M*dx0);
dv=1./(N*dy0);
u=ones(N,1)*[0:M/2-1 -M/2:-1]*du;                      %Note order of points for FFT
v=[0:N/2-1 -N/2:-1]'*ones(1,M)*dv;
H=exp(-i*pi*lambda*z*(u.^2+v.^2));         %Fourier transform of kernel
f1=ifft2(fft2(f0).*H);                                 %Convolution
dx1=dx0;dy1=dy0;
x1=ones(N,1)*[-M/2:M/2-1]*dx1;                         %Baseline for output
y1=[-N/2:N/2-1]'*ones(1,M)*dy1;