Distribution characteristics of intensity and phase vortices of speckle fields produced by N-pinhole random screens
Liu Man†a),b), Cheng Chuan-Fu‡b), Ren Xiao-Rongb)
       
The local probability distributions of ε . (a)  N = 4, (b) N = 8, (c)  N = 10, (d)  N = 12, (e) N = 16, (f) N = 20, (g) a large single ring aperture and (h) a large single circular aperture.