Figure 4: Measured magnetic field distributions near the metamaterial cloak at the optimum cloaking frequency of 9.8 GHz. Field distributions for free space, bared aluminum cylinder and cloaked aluminum cylinder, respectively, when EM waves are incident with an angle of 0° [(a)–(c)], 22.5° [(d)–(f)], and 45° [(g)–(i)], respectively. The black-line squares and the gray areas in (b), (e), and (h) represent the unmeasured region and the aluminum cylinder, respectively. The black arrows in (a), (d), and (g) indicate the incidence of the point source of EM waves. The bold black line squares and the blue squares in (c), (f), and (i) represent the unmeasured and hidden regions, respectively. The unmeasured areas are filled with simulated -field distributions. Insets: the enlarged image of -field distributions in the cloak.