initial

The optics_toolkit code taken from
http://mercury.pr.erau.edu/~greta9a1/downloads/index.html

the older version is also available at mathwork web site
http://www.mathworks.com/matlabcentral/fileexchange/15459-basic-paraxial-optics-toolkit

1 files changed, 81 insertions, 0 deletions

diff --git a/axial/beamplot.m b/axial/beamplot.m
new file mode 100644
index 0000000..5c3349d
--- /dev/null
+++ b/axial/beamplot.m
@@ -0,0 +1,81 @@
+% Accepts the q factor of a Gaussian beam and plots the 1/e^2 intensity envelope.

+% 

+% SYNTAX: [handle,xend,yend]=beamplot(q,z,<,x,y,theta,n,lambda,...

+%                                         attitudes,plotsuppress>);

+%

+% INPUT ARGUMENTS:

+% q         = Gaussian beam complex radius of curvature "q".

+%             If q is a vector, a beam is plotted for each element.

+% z         = vector along beam axis over which to plot the envelope

+% x,y       = position of the point at which q is specified, default=0,0.

+% theta     = rotation of optic axis counterclockwise relative to x-axis,

+%             defaul=0 (degrees)

+% n         = index of medium in which the beam propagates

+% lambda    = wavelength, default=1064 nm or 4.189e-5 inches

+% plotsuppress  = set to 1 to suppress plotting, default 0.

+%

+% OUTPUT ARGUMENTS:

+% handle    = handle of the trace plotted

+% xend,yend = position of the end of the optic axis over which the beam

+%             was plotted.

+%

+% Last Modified: June 23, 2004 by Andri M. Gretarsson.

+%

+%--------------------------------------------------------------------------------

+% SYNTAX: [handle,xend,yend]=beamplot(q,z,<,x,y,theta,n,lambda,plotsuppress>);

+%--------------------------------------------------------------------------------

+

+function [handle,xend,yend]=beamplot(q,z,varargin)

+

+if nargin>=3, x=varargin{1}; else x=0; end

+if nargin>=4, y=varargin{2}; else y=0; end

+if nargin>=5, theta=varargin{3}*pi/180; else theta=0; end

+if nargin>=6, n=varargin{4}; else n=1; end

+if nargin>=7, lambda=varargin{5}; else lambda=1064e-9; end

+if nargin>=9, plotsuppress=varargin{7}; else plotsuppress=0; end

+

+if size(z,1)>size(z,2)

+    z=transpose(z);

+end

+if size(q,1)<size(q,2)

+    q=transpose(q);

+end

+lambda=lambda/n;

+w0=sqrt(imag(q).*lambda/pi);

+L=-real(q).*ones(size(w0));

+

+w_upper=zeros(length(L),length(z)); w_lower=w_upper; xend=zeros(length(L)); yend=xend;

+handle=zeros(2,length(L)); plotcolors=colormap;

+

+for s=1:length(L)

+    w_upper=w0(s)*sqrt(1+(lambda*(z-L(s))/pi/w0(s)^2).^2);

+    w_lower=w_upper;

+

+    upperenv=[z;w_upper];

+    lowerenv=[z;-w_lower];

+    rotmat=[[cos(theta), -sin(theta)];[sin(theta), cos(theta)]];

+    rotupperenv=rotmat*upperenv;

+    rotupperenv(1,:)=rotupperenv(1,:)+x;

+    rotupperenv(2,:)=rotupperenv(2,:)+y;

+    rotlowerenv=rotmat*lowerenv;

+    rotlowerenv(1,:)=rotlowerenv(1,:)+x;

+    rotlowerenv(2,:)=rotlowerenv(2,:)+y;

+

+    xend=max(z)*cos(theta)+x;

+    yend=max(z)*sin(theta)+y;

+

+    if plotsuppress~=1

+        if s==1,

+            orighold=get(gca,'nextplot');

+            handle(:,s)=plot(rotupperenv(1,:),rotupperenv(2,:),'b-',rotlowerenv(1,:),rotlowerenv(2,:),'b-');

+            set(handle(:,s),'color',plotcolors(mod(s,end)+1,:));

+        else

+            set(gca,'nextplot','add');

+            handle(:,s)=plot(rotupperenv(1,:),rotupperenv(2,:),'b-',rotlowerenv(1,:),rotlowerenv(2,:),'b-');

+            set(handle(:,s),'color',plotcolors(mod(s,end)+1,:));            

+        end

+        if s==length(L)

+            set(gca,'nextplot',orighold);

+        end

+    end

+end
\ No newline at end of file