drawing gaussian wave in matlab

How can I plot a 2D profile of a red laser beam (λ = 600 nm) with a beam-waist of 0.5 mm that is in z-y or z-x plane, where z (0<z<20 m) ) is the propagation direction?

[Image Analyst]

Do you have a formula for beam diameter as a function of distance from the source?

[Yasemin]

yes, travels a distance of 20 meters.

[Yasemin]

w(z)=w0*sqrt(1+(z/z0)^2)

Answer 1

[Image Analyst]

Try this:

% Optional initialization steps
clc;    % Clear the command window.
close all;  % Close all figures (except those of imtool.)
clear;  % Erase all existing variables. Or clearvars if you want.
workspace;  % Make sure the workspace panel is showing.
format long g;
format compact;
fontSize = 18;

% Define how many elements you want along your z axis, 
% which runs from 0 to 20.
numElements = 2000;
z = linspace(0, 20, numElements);
% Define z0 as something.  (It's not z(0) which has a value of zero.
z0 = 5;
% Define w0 as something.
w0 = 3;
w = w0 * sqrt(1 + (z / z0) .^ 2);

% Plot w vs z
plot(z, w, 'b-', 'LineWidth', 3);
grid on;
title('Beam Waist Diameter as a Function of z', 'FontSize', fontSize);
xlabel('z [meters]', 'FontSize', fontSize);
ylabel('Waist Diameter [meters?]', 'FontSize', fontSize);
g = gcf;
g.Name = 'Demo by Image Analyst for Yasemin';
g.NumberTitle = 'off';
g.WindowState = 'maximized'

[Yasemin]

thank you, this explanation was a clue to solve my question

[Image Analyst]

You're welcome.

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