Achromatic varifocal metalens for the visible spectrum

Abstract

Metasurface optics provide an ultra-thin alternative to conventional refractive lenses. A present challenge is in realizing metasurfaces that exhibit tunable optical properties and achromatic behavior across the visible spectrum. Here, we report the design, fabrication, and characterization of metasurface lenses ("metalenses") that use asymmetric TiO2 nanostructures to induce a polarization-dependent optical response. By rotating the polarization of linearly-polarized input light, the focal length of a 40 micrometer-diameter metalens is tuned from 220-550 micrometers with nearly diffraction-limited performance. We show that imparting a wavelength-dependent polarization rotation on incident light enables achromatic focusing over a wide band of the visible spectrum, 483-620 nm. We use this property to demonstrate varifocal color imaging with white light from a halogen source. Tunable achromatic metalenses may be useful for applications in imaging and display.

Main text: 9 pages, 5 figures. Supplemental Information: 12 pages, 10 figures

References in corpus (8)

• Dielectric Metasurfaces for Complete Control of Phase and Polarization with Subwavelength Spatial Resolution and High Transmission
• Subwavelength-thick Lenses with High Numerical Apertures and Large Efficiency Based on High Contrast Transmitarrays
• Achromatic Metalens in the Visible and Metalens with Reverse Chromatic Dispersion
• High efficiency dielectric metasurfaces at visible wavelengths
• A broadband achromatic polarization-insensitive metalens consisting of anisotropic nanostructures
• Flat Dielectric Grating Reflectors with High Focusing Power
• Controlling the sign of chromatic dispersion in diffractive optics with dielectric metasurfaces
• Low Contrast Dielectric Metasurface Optics

Cited by in corpus (6)

• Electrically Tunable Multifunctional All-Dielectric Metasurfaces Integrated with Liquid Crystals in the Visible
• Computational inverse design for cascaded systems of metasurface optics
• Tunable Polarization-Multiplexed Achromatic Dielectric Metalens
• Simultaneous achromatic and varifocal imaging with quartic metasurfaces in the visible
• Compact optical polarization-insensitive zoom metalens-doublet
• Ultra-compact, high-NA achromatic multilevel diffractive lens via metaheuristic approach