PhotoniX (Nov 2022)
Ultracompact multifunctional metalens visor for augmented reality displays
Abstract
Abstract Virtual reality (VR) and augmented reality (AR) have found widespread applications in education, engineering, healthcare, and entertainment. However, these near-eye displays are often bulky and heavy, and thus are not suitable for long-term wearing. Metalenses, with an ultra-thin formfactor, subwavelength modulation scale, and high modulation flexibility, are promising candidates to replace the conventional optics in AR display systems. In this work, we proposed and fabricated a novel reflective dielectric metalens-visor based on Pancharatnam-Berry phase with see-through capability. It achieves diffraction-limited focusing behavior for the reflected red light, while keeping a good transmission spectrum in the visible region. Hence, this single piece metalens-visor can perform the function of two integrated elements simultaneously: an eyepiece and an optical combiner, which in turn greatly reduces the weight and the size of an AR display. We have implemented a proof-of-concept AR display system employing the metalens-visor, and experimentally demonstrated color AR images with good image quality. This work reveals the great potential of multi-functional metasurface devices which enables optical integration in interdisciplinary applications including wearable displays, biological imaging, and aeronautic optical instruments.
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