Digital Diffraction - Figure 9 Figure 9.
Glasslike mask has a diffraction pattern with faint annular features.
First the random-mask procedure described in Figure 8 was used to place 5,000 densely packed apertures in a square 20 units on a side. Then a second procedure thinned this array by marching through the list of apertures and rejecting any point that lay within a radius of 1 unit of another point already accepted. For the specific instance shown here 249 points were selected.