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# Scriptfile: fresnel1.lsf
#
# Description: This file analyses the data in fresnel1.fsp
#
#
# Copyright 2008, Lumerical Solutions, Inc.
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# get the index data and image the lens shape
x = getdata("index","x");
y = getdata("index","y");
n = getdata("index","index_z");
image(x*1e3,y*1e6,real(n),"x (mm)","y (microns");

# get the near E field. Plot the amplitude and phase
Ez = getdata("T","Ez");
x = getdata("T","x");
plot(x*1e3,abs(Ez),"x (mm)","|Ez|");
phase = unwrap(angle(Ez))*180/pi;
phase = phase - phase(find(x,0));
plot(x*1e3,phase,"x (mm)","angle(Ez) (degrees)");

# do a far field projection onto a 2D surface to find the focal distance
n_projection = 1.0; # air
x1 = linspace(-2.5e-3,2.5e-3,51);
y1 = linspace(-100e-3,-300e-3,51);
Efar = farfieldexact2d("T",x1,y1,1,n_projection);
Efar = sum(abs(Efar),3);
image(x1*1e3,y1*1e3,Efar,"x (mm)","y (mm)");
plot(y1*1e3,Efar(find(x1,0),1:length(y1)),"y (mm)","|E|^2");

# calculate |E|^2 vs x for a high resolution plot at the focal plane
x2 = linspace(-2.5e-3,2.5e-3,1000);
y2 = -200e-3;
Efar2 = farfieldexact2d("T",x2,y2,1,n_projection);
Efar2 = sum(abs(Efar2),3);
plot(x2*1e3,Efar2,"x (mm)","|E|^2 at focal plane");