Figure 7
From: Planar binary-phase lens for super-oscillatory optical hollow needles
Experimental obtained optical intensity in the designed range of the optical hollow needle. (a)–(f) The color maps of 2-dimentional transverse optical intensity distributions on the XY plane and the transverse optical intensities along the x-axis obtained at different propagation distances of 300λ, 301.5λ, 303λ, 304.5λ, 306λ, and 307.5λ, respectively, where the optical intensity is plotted in arbitrary unit. The corresponding FWHM of the central hollow ring is 0.44λ, 0.51λ, 0.419λ, 0.408λ, 0.38λ, and 0.359λ, respectively.
