Orbital Angular Momentum Vertex Beam design based on 4 phase level
61 vues (au cours des 30 derniers jours)
Afficher commentaires plus anciens
Hello Everyone,
I designed Orbital Angular Momentum (OAM) using the following MATLAB code
NUM = 100;
x = linspace(-12,12,NUM);
y = x;
[X,Y] = meshgrid(x,y);
charge =1;
theta= charge*atan2(X,Y);
Amp = ones(NUM);
OAM = Amp.*exp(1i*theta);
This code will generate OAM consisting of multi phase values. Whereas, I need an OAM which consist of only 4 phase values. Here, for the understanding I am attaching a picture of the OAM phase plate. A simple distribution like the following picture or generating such OAM distribution by formula both can help for my requirement.
1 commentaire
Siti Hasunah
le 6 Sep 2023
Hi, I tried to generate an OAM wave-front phase using MATLAB and want to see the results with different OAM mode. I managed to get wave-front for OAM mode = 0 and 1, but then the result doesn't differ for higher OAM mode more than 1. How can I get the different wave-front just like below attached picture of mode l = 2?
These are the codes I used to generate the wave front:
% Define parameters
desired_distance = 2.0; % Desired transmission distance (2 meters)
wavelength = 1.551e-6; % Wavelength (in meters)
num_points_x = 200; % Number of points in the x-direction
num_points_y = 200; % Number of points in the y-direction
x = linspace(-desired_distance/2, desired_distance/2, num_points_x);
y = x;
[X, Y] = meshgrid(x, y);
% OAM mode parameters
l = 1; % OAM mode order (change to the desired order)
k = 2 * pi / wavelength; % Wavenumber
% Calculate azimuthal angle theta
theta = atan2(Y,X);
% Calculate the OAM wave-front phase
phase = l * theta;
% Display the phase pattern
figure;
imagesc(x, y, phase);
axis equal;
title(['OAM Mode (l = ', num2str(l), ') Wave-Front Phase Pattern']);
xlabel('X (meters)');
ylabel('Y (meters)');
colorbar;
Réponse acceptée
Plus de réponses (1)
Image Analyst
le 28 Jan 2023
How about this:
NUM = 100;
x = linspace(-12,12,NUM);
y = x;
[X,Y] = meshgrid(x,y);
charge =1;
theta= charge*atan2d(X,Y);
subplot(2, 1, 1);
imshow(theta, []);
impixelinfo
Amp = zeros(NUM);
% Top triangle.
mask = theta <= -135 | theta > 135;
Amp(mask) = pi/2;
% Right triangle.
mask = theta >= 45 & theta < 135;
Amp(mask) = 0
% Bottom triangle.
mask = theta >= -45 & theta < 45;
Amp(mask) = 3 * pi / 2
% Left triangle.
mask = theta <= -45 & theta > -135;
Amp(mask) = pi
subplot(2, 1, 2);
imshow(Amp, []);
impixelinfo
colorbar
2 commentaires
Image Analyst
le 7 Fév 2023
Modifié(e) : Image Analyst
le 8 Fév 2023
I don't know what that is. Do you have an example?
If you need 8 or more sectors, you can simply put my triangle code into a loop over all sector angles. Is that what you want to do? I think you're skilled enough to do that -- just make a for loop.
Voir également
Catégories
En savoir plus sur Guidance, Navigation, and Control (GNC) dans Help Center et File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!