###########################################################################
# Scriptfile: usr_custom_source.lsf
#
# Description:
# This is an example of how to create an arbitrary source using the
# usr_createsource.lsf script file.  In this example, we create a radially 
# polarized source.
# 
# Copyright 2008, Lumerical Solutions, Inc.
###########################################################################

# clear all current variables
clear;

# #################################################################
# To create your desired source modify this section:
# this data could even come from a monitor in a previous simulation

lambda = 650e-9;
refractive_index = 1;

# in order to inject this source in 3D, define y and z vectors
x = linspace(-10e-6,10e-6,100);
y = linspace(-10e-6,10e-6,100);
z = 0; # this is z z-normal source

# now we creat a 2d surface
X = meshgridx(x,y);
Y = meshgridy(x,y);

# create radially polarized beam
phi=atan2(X,Y);

# x-polarized beam
Ex = 1;
Ey = 0;
Ez = 0;

# Create gaussian envelope
FWHM = 8e-6;
sigma = FWHM / ( 2*sqrt(2*log(2)) );
envelope = exp( - (X^2)/(2*sigma^2) - (Y^2)/(2*sigma^2) );

# apply envelope to fields
Ex = Ex*envelope;
Ey = Ey*envelope;
Ez = Ez*envelope;


# plot Er and Etheta
if (1) { # 1=make plots, 0=don't make plots
  Er = Ex*sin(phi)+Ey*cos(phi);
  Etheta = -cos(phi)*Ex+Ey*sin(phi);
  image(x*1e6,y*1e6,envelope,"x (um)","y (um)","envelope");
  image(x*1e6,y*1e6,abs(Er),"x (um)","y (um)","abs(Er) Source");
  image(x*1e6,y*1e6,abs(Etheta),"x (um)","y (um)","abs(Etheta) Source");
  image(x*1e6,y*1e6,abs(Ex),"x (um)","y (um)","abs(Ex) Source");
  image(x*1e6,y*1e6,abs(Ey),"x (um)","y (um)","abs(Ey) Source");
}

# end of user modification section
###########################################################


# don't modify the following commands
dx = x(2)-x(1);
dy = y(2)-y(1);

# fill in the variables needed for createsource.lsf
include_H = 0; # 1: H fields are defined, 0: H fields defined from E fields
wavelength = lambda;
power = 1;
index = refractive_index;
axis1 = 1; # x axis
axis2 = 2; # y axis
min1 = x(1)-dx/2;
max1 = x(length(x)) + dx/2;
min2 = y(1)-dy/2;
max2 = y(length(y)) + dy/2;
depth = z;
n1 = length(x);
n2 = length(y);
sourcefilename = "sourcefile";

#create the source by calling usr_create_fld.lsf
usr_create_fld;