PRISM Calculates deviation angle of a prism

by Chuck DiMarzio Northeastern University March 2010

See text Chapter 2 for details.
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alpha=30;  % Set the prism angle (degrees)
n=1.5;     % Index of refraction
theta1=(0:60);  % Vary the input angle
% theta2p is the angle of incidence on second surface
theta2p=asind(sqrt(n^2-(sind(theta1)).^2)*sind(alpha)-...
              sind(theta1)*cosd(alpha));
delta=-alpha+theta1+theta2p; % Total deviation
deltamin=2*asind(n*sind(alpha/2))-alpha % Print out minimum deviation
theta1_for_min=asind(n*sind(alpha/2)) % and associated angle
fig1=figure;plot(theta1,delta,'-',theta1_for_min,deltamin,'o');grid on;
xlabel('\theta_1, Angle of Incidence')
ylabel('\delta, Angle of Deviation')
deltamin =
   15.6886
theta1_for_min =
   22.8443