Flat Optics: from Metalenses to New Polarization Optics and New Routes to Vector Beam Generation
Arrays of optically thin, sub-wavelength spaced optical elements (meta surfaces) have major potential for wavefront shaping through local control of the phase, amplitude and polarization of light . Flat optics has emerged from this approach  with the goals of replacing refractive lenses in most applications requiring aberrations’ correction [3,4] as well as conventional phase plates used in polarization optics  and last but not least of providing a new path to the creation of structured light .
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