#############################################################
# scriptfile: evanescent.lsf
#
# This file calculates the reflection spectrum for a 2 and 3
# layer dielectric stack. It does both polarizations
# (TE and TM) and compares to the analytic result.
#
# Copyright 2010, Lumerical Solutions, Inc.
#############################################################

#runsweep("sweep");

select("multilayer stack");
num_layers = get("num_layers");   

R = getsweepresult("sweep", "R");
T = getsweepresult("sweep", "T"); 
theta= R.source_angle;
f    = R.f;

# define the indices and layer thicknesses
n = matrix(num_layers);
d = matrix(num_layers);

n(1) = getnamed("multilayer stack","index");       
n(2) = 1;
d(1) = 0; #does not matter
d(2) = 0.5e-6; # does not matter if 2 layer stack
if(num_layers==3){ n(3) =  n(1); } 

RT_Theory = stackrt(n,d,f,theta);

plot(theta*180/pi,-R.T,T.T,RT_Theory.Rs,RT_Theory.Ts,"angle (degrees)","R and T","R,T vs angle");
legend("R FDTD","T FDTD","R Theory","T Theory");