%%?Intensity?distribution?of?Gaussian?with?paraxial?approximation?
?%近軸高斯光束分布　
clc?
clear?
close?all?
?
w0=40e-3;??????????????????%?waist?size?束腰半徑
lambda=30e-3;??????????????%?wavelength?　波長
k0=2*pi/lambda;????????????%?wavenumber?in?free?space　波數?
I0=1;?
zR=pi*w0^2/lambda;?????????%??瑞利長度
r=linspace（-200200401）*1e-3;??
z=linspace（-400400801）*1e-3;?
wz=w0*sqrt（1+（z/zR）.^2）;????%?光斑半徑?
Rz=z+zR.^2./z;??????????????%?光波波前的曲率半徑
phiz=atan（z./zR）;???????????%Gouy?phase?shift?
I=zeros（length（r）length（z））;?
E=zeros（length（r）length（z））;?
?
for?ii=1:le