Meta-Lens Doublet in the Visible Region.

Recently, developments in meta-surfaces have allowed for the possibility of a fundamental shift in lens manufacturing-from the century-old grinding technology to nanofabrication-opening a way toward mass producible high-end meta-lenses. Inspired by early camera lenses and to overcome the aberrations of planar single-layered meta-lenses, we demonstrate a compact meta-lens doublet by patterning two metasurfaces on both sides of a substrate. This meta-lens doublet has a numerical aperture of 0.44, a focal length of 342.5 μm, and a field of view of 50° that enables diffraction-limited monochromatic imaging along the focal plane at a wavelength of 532 nm. The compact design has various imaging applications in microscopy, machine vision, and computer vision.