Fig. 8
From: Planar metasurface-based concentrators for solar energy harvest: from theory to engineering
Schematic of chromatic (left side of (I)) and achromatic (right side of (I)) meta-lens. (II) Phase profile of a broadband achromatic meta-lens at an arbitrary wavelength. (III) Operation efficiency at the corresponding focal plane as a function of wavelength. (IV) Experimental (top row) and numerical (bottom row) intensity profiles of broadband achromatic meta-lens along axial planes. Reproduced with permission [201]. Copyright 2018, NPG