Fig. 1

Geometric origami of silicon optoelectronics for the hemispherical electronic eye. a Schematic illustration of the net of half truncated icosahedron being folded into a hemisphere. 676 polygon blocks consisting of pentagons and hexagons were mapped into a net of subdivided half truncated icosahedron which was then folded to form a hemisphere. b A photograph of the half truncated icosahedron based on polygon blocks of metal-coated silicon nanomembranes printed on a flexible polyimide film. The completed net was folded into a convex hemisphere by inserting the net into a circular hole of a metal fixture. Scale bar, 1 mm. c Schematic illustration of the net of half truncated icosahedron based on silicon nanomembranes pressed into a hemispherical concave mold. d Schematic illustration of the net of half truncated icosahedron based on silicon nanomembranes covered on a hemispherical convex mold. e A photograph of a silicon optoelectronics-based hemispherical focal plane array formed using the concave mold-based origami approach shown in c. Inset image shows the flat focal plane array before folding. Scale bar, 2 mm. f A photograph of a silicon optoelectronics-based convex hemispherical eye camera formed using the convex mold-based origami approach shown in d. Inset image shows the flat eye camera before folding. Scale bar, 2 mm