(a) Broadband (white) light focusing by large-area plasmonic microlens arrays. Inset shows the SEM image of a plasmonic microlens. Reprinted from reference [98] with permission. (b) SEM image of a planar plasmonic metalens. (c) The intensity profiles of the cross-polarized scattered light from the metalens at the transverse plane. (d) The intensity maps depicted on two orthogonal cross-section planes. Reprinted from reference [99] with permission. (e) Calculated intensity of a dual-polarity plasmonic lens indicates that the lens functions as a positive lens for right circularly polarized light. (f) The same lens changes its polarity and turns into a negative lens. Reprinted from reference [100] with permission.