Figure 3
From: Planar binary-phase lens for super-oscillatory optical hollow needles
(a) The optical intensity distribution in the XZ propagation plane obtained from Eq. (2) using the vectorial angular spectrum method, where the intensity is plotted in arbitrary unit. (b) The theoretical central ring peak intensity (red), the transverse FWHM (blue), and sidelobe ratio (green) distributions along the propagation direction, where the black and wine-colored dashed-dotted lines indicate the diffraction limit and super-oscillatory criterion, respectively.
