make1

clear
[x y] = meshgrid(linspace(-1.02,1.02,2048));
r = sqrt(x.^2+y.^2);
y = flipud(y);
theta = atan2(y,x)*180/pi;
subplot(1,2,1);
imshow(r);
subplot(1,2,2);
imshow((theta+180)/360);
close all
wh1 = mod(theta,20)>10;
imshow(wh1);
seq = [1 0.85 .7 .55 .45 .35 .25 .23];
r2 = and(r<=1.02,r>1);
pat = r2;
r2 = and(r<=seq(1),r>seq(2));
pat = pat + r2.*wh1;
r2 = and(r<=seq(2),r>seq(3));
pat = pat + r2.*~wh1;
r2 = and(r<=seq(3),r>seq(4));
pat = pat + r2.*wh1;
r2 = and(r<=seq(4),r>seq(5));
pat = pat + r2.*~wh1;
r2 = and(r<=seq(5),r>seq(6));
pat = pat + r2.*wh1;
r2 = and(r<=seq(6),r>seq(7));
pat = pat + r2.*~wh1;
r2 = and(r<=seq(7),r>seq(8));
pat = pat + r2;
imshow(~pat);
imwrite(~pat,'annulus.jpg');