光强分布MATLAB

一、高斯光束模拟的焦点附近光场分布for n=1:10

I=0.1*n;

a=sqrt(1./I-1);

z=0:0.0001:a;

r=sqrt(0.5.*(1+z.^2).*log(1./(I.*(1+z.^2))));

plot(z,r, '-');

hold on

end

右半边：

for n=1:10

I=0.1*n;

a=sqrt(1./I-1);

z=0:0.0001:a;

r1=sqrt(0.5.*(1+z.^2).*log(1./(I.*(1+z.^2))));

r2=-sqrt(0.5.*(1+z.^2).*log(1./(I.*(1+z.^2))));

plot(z,r1, '-');

hold on

plot(z,r2, '-');

hold on

end

全图：

clear all

for n=1:10

I=0.1*n;

a=sqrt(1./I-1);

z=-a:0.00001*a:a;

r1=sqrt(0.5.*(1+z.^2).*log(1./(I.*(1+z.^2))));

r2=-sqrt(0.5.*(1+z.^2).*log(1./(I.*(1+z.^2))));

plot(z,r1, '-'); axis equal

hold on

plot(z,r2, '-'); axis equal

hold on

end

xlabel('Z(λ)/m');

ylabel('r(λ)/m');

title('焦点附近光场分布')

带空间坐标：

clear all

for n=1:10

I=0.1*n;

w0=200e-9;

wl=780e-9;

a=pi*w0^2*sqrt(1./I-1)/wl;

z=-a:0.0001*a:a;

r1=w0*sqrt(0.5.*(1+(wl/(pi*w0^2)).*z.^2).*log(1./(I.*(1+(wl/(pi*w0^2)).*z.^2)))); r2=-w0*sqrt(0.5.*(1+(wl/(pi*w0^2)).*z.^2).*log(1./(I.*(1+(wl/(pi*w0^2)).*z.^2)))); plot(z,r1, '-'); axis equal

hold on

plot(z,r2, '-'); axis equal

hold on

end

xlabel('Z(λ)/m');

ylabel('r(λ)/m');

title('焦点附近光场分布')

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Y A x i s T i t l e X Axis Title

二、焦点附近的三维光场分布

三、高斯光束在传播过程中，焦点处的光强分布

1、高斯光束在光腰处的三维光强分布图

clear all

N=200;

w0=200e-9; %高斯光束的光腰半径

r=linspace(0,3*w0,N);

eta=linspace(0,2*pi,N);

[rho,theta]=meshgrid(r,eta); %生成极坐标网格

[x,y]=pol2cart(theta,rho); %将极坐标网格转化为直角坐标网格

I=exp(-2*rho.^2./w0.^2); %高斯光束在归一化的光强值

surf(x,y,I);

colormap hot; %colormap gray线性灰度图colormap hot热色颜色图去掉这句命令为彩图

shading interp;

xlabel('x /m');

ylabel('y /m');

zlabel('intensity /a.u.');

axis([-3*w0 3*w0 -3*w0 3*w0 0 1])

title('焦点附近三维光场分布')

colorbar;

2、高斯光束在光腰处的二维光强分布图

clear all

N=200;

w0=200e-9; %高斯光束的光腰半径

x=linspace(-3*w0,3*w0,N);

y=linspace(-3*w0,3*w0,N);

X=meshgrid(x,y);

Y=meshgrid(y,x);

Y=Y';

R=sqrt(X.^2+Y.^2);

I=exp(-2*R.^2./w0.^2);

imagesc(x,y,I,[0 1]); axis equal

colormap hot; %colormap gray线性灰度图colormap hot热色颜色图去掉这句命令为彩图

colorbar;

xlabel('x /m');

ylabel('y /m');

axis([-3*w0 3*w0 -3*w0 3*w0])

title('焦点附近三维光场分布')

3、高斯光束在传播过程中，焦点处的三维光强分布clear all

w0=200e-9; %高斯光束的光腰半径wavelength=780e-9; %高斯光束的光波长

ZR=pi*w0^2/wavelength; %高斯光束的瑞利长度

L=3*ZR; %高斯光束的传输范围

N=200;

z=linspace(-L,L,N);

r=linspace(-4*w0,4*w0,N);

[pr,pz]=meshgrid(r,z);

wz=w0*sqrt(1+(wavelength*pz/pi/w0^2).^2);

I=w0^2./wz.^2.*exp(-2*pr.^2./wz.^2);

surf(pz,pr,I);

shading interp;

xlabel('Z(λ) /m');

ylabel('r(λ) /m');

zlabel('intensity /a.u.');

axis([-3*ZR 3*ZR -Inf Inf -Inf Inf])

title('焦点附近三维光场分布')