Ultracompact multifunctional metalens visor for augmented reality displays

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.

Metasurface-enabled augmented reality display: a review

“…Assisted by inverse design method, RGB multiwavelength achromatic TiO2 metalenses of even larger diameters (up to 1 cm) have recently been demonstrated, 153 which can be potentially used to provide larger eye boxes for metalens-based AR display systems. Li et al 171 . demonstrated an AR display system employing a geometric-phase-based, reflection-type Si metalens, which performs similar to a lens-HOE and focuses oblique image-bearing light onto the pupil of the observer [Fig.…”

High birefringence liquid crystals with a wide temperature range and low melting point for augmented reality displays

“…Broad temperature adaptability is a key performance evaluator for the widespread applications of all optoelectronic devices, which have attracted significant attention in various fields, such as proton exchange membrane fuel cells, 1,2 perovskite solar cells, 3,4 lithium ion batteries, [5][6][7] supercapacitors, 8,9 and liquid crystal (LC) devices. [10][11][12][13] Augmented reality (AR) displays, one of the emerging research hotspots of LC devices, [14][15][16][17] are subject to device failure at low temperature resulting from the temperature-dependent properties of the LC materials used in AR displays. Therefore, there is an urgent need to find effective ways to lower the working temperature of LC devices to enhance their ambient temperature tolerance.…”

Multiwavelength Achromatic Metalens in Visible by Inverse Design

“…[1,2] The advent of metasurface optics has made it possible to drastically reduce the size of bulky conventional-optics counterparts while maintaining or even improving their performance. Metalenses have been intensively studied in recent years and are considered in numerous optical system applications, such as augmented reality (AR), [3][4][5] light-field imaging, [6][7][8] spectral tomographic imaging, [9] quantum light sources, [10] and super resolution. [11,12] The development of other functions, such as zooming, will further promote the engineering applications of metalenses.…”