Planar Lenses at Visible Wavelengths
Abstract
Sub-wavelength resolution imaging requires high numerical aperture (NA) lenses, which are bulky and expensive. Metasurfaces allow the miniaturization of conventional refractive optics into planar structures. We show that high-aspect-ratio titanium dioxide metasurfaces can be fabricated and designed as meta-lenses with NA = 0.8. Diffraction-limited focusing is demonstrated at wavelengths of 405 nm, 532 nm, and 660 nm with corresponding efficiencies of 86%, 73%, and 66%. The meta-lenses can resolve nanoscale features separated by sub-wavelength distances and provide magnification as high as 170x with image qualities comparable to a state-of-the-art commercial objective. Our results firmly establish that meta-lenses can have widespread applications in laser-based microscopy, imaging, and spectroscopy.
Cite
@article{arxiv.1605.02248,
title = {Planar Lenses at Visible Wavelengths},
author = {Mohammadreza Khorasaninejad and Wei Ting Chen and Robert C. Devlin and Jaewon Oh and Alexander Y. Zhu and Federico Capasso},
journal= {arXiv preprint arXiv:1605.02248},
year = {2016}
}