MATLAB: How to create grating diffraction pattern.

gratingMATLAB

How to create a code to plot the intensity of the light I see from the grating diffraction in theory.
The graph shows only the diffraction ranking at zero. I want the graph to show the first number diffraction.
Who can see if it might go wrong? Please help me.
x = linspace(-50, 50, 500);
A = 4*W;
lambda = 632.8e-9;                 % m
D =  1;                         % Distance to the observation plane m
W = 38e-6;                         % slit width(m)
fx = x/(lambda*D);              % frequency coordinat
I = (A^2/(lambda^2*D^2)) .* sinc(2*W*fx).^2; 
figure
plot(x, I)
grid
xlabel('fx')
ylabel('Intensity')

Best Answer

x = linspace(-50, 50, 500);
lambda = 632.8e-9;                 % m
D =  1;                         % Distance to the observation plane m
W = 38e-6;  
A = 4*W;% slit width(m)
fx = x/(lambda*D);              % frequency coordinat
I = (A^2/(lambda^2*D^2)) .* sinc(2*W*fx).^2; 
figure, plot(x,I)
grid
xlabel('fx')
ylabel('Intensity');
% Just repeat the same row multiple times
% For Better visualisation
grad_pattern=repelem(I,[50],[1]); 
figure,imshow(grad_pattern,[]);
title('Diffraction Pattern');
Related Question