function hw4_7_public

% 2.997 Optical Engineering / George Barbastathis
% Massachusetts Institute of Technology
% 10/12/1999

[x,y]=meshgrid(-50:0.1:50,-50:0.1:50);

figure(1)
ii1=plsph(1000,0.05,x,y);

figure(2)
ii2=plsph(1000,0.1,x,y);

figure(3)
ii=plsph(500,0.1,x,y);