Vectorial liquid-crystal holography

eLight, Год журнала: 2024, Номер 4(1)

Опубликована: Март 5, 2024

Abstract Vectorial optics with fine inhomogeneous polarization control are highly desired. Metasurfaces have been captivated a promising candidate, but their static post-fabrication geometry largely limits the dynamic tunability. Liquid crystal (LC) is usually employed as an additional index-changing layer together metasurfaces. Unfortunately, most of reported LCs only impart varying uniform phase on top that from metasurface, which we term “scalar” LC optics. Here, pixelate single-layer to display versatile and tunable vectorial holography, in amplitude could be arbitrarily independently controlled at spatial positions. Furthermore, subtle LC-holography highlights broadband electrically-switchable functionalities. Our holography reveals significant opportunities for advanced cryptography, super-resolution imaging, many other applications.

Язык: Английский

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Multiplexed manipulation of orbital angular momentum and wavelength in metasurfaces based on arbitrary complex-amplitude control

Light Science & Applications, Год журнала: 2024, Номер 13(1)

Опубликована: Апрель 28, 2024

Abstract Due to its unbounded and orthogonal modes, the orbital angular momentum (OAM) is regarded as a key optical degree of freedom (DoF) for future information processing with ultra-high capacity speed. Although manipulation OAM based on metasurfaces has brought about great achievements in various fields, such currently remains at single-DoF level, which means multiplexed other DoFs still lacking, greatly hampering application beams advancement metasurfaces. In order overcome this challenge, we propose idea coherent pixel (MCP) This approach enables arbitrary complex-amplitude under incident lights both plane waves, basis have realized DoF control wavelength. As result, MCP method expands types can be simultaneously responded by metasurfaces, enriches capability creates applications encryption demultiplexer. Our findings not only provide design high-security high-capacity but also raise level OAM, offering potential multifunctional nanophotonic devices future.

Язык: Английский

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Breaking the in-coupling efficiency limit in waveguide-based AR displays with polarization volume gratings

Light Science & Applications, Год журнала: 2024, Номер 13(1)

Опубликована: Авг. 12, 2024

Abstract Augmented reality (AR) displays, heralded as the next-generation platform for spatial computing, metaverse, and digital twins, empower users to perceive images overlaid with real-world environment, fostering a deeper level of human-digital interactions. With rapid evolution couplers, waveguide-based AR displays have streamlined entire system, boasting slim form factor high optical performance. However, challenges persist in waveguide combiner, including low efficiency poor image uniformity, significantly hindering long-term usage user experience. In this paper, we first analyze root causes uniformity displays. We then discover elucidate an anomalous polarization conversion phenomenon inherent volume gratings (PVGs) when incident light direction does not satisfy Bragg condition. This new property is effectively leveraged circumvent tradeoff between in-coupling eyebox uniformity. Through feasibility demonstration experiments, measure leakage multiple PVGs varying thicknesses using laser source liquid-crystal-on-silicon engine. The experiment corroborates phenomenon, results align simulation well. To explore potential such further, design simulate display 50° field view. achieving first-order PVG, are improved by 2 times 2.3 times, respectively, compared conventional couplers. groundbreaking discovery holds immense revolutionizing promising higher superior

Язык: Английский

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Ultracompact and high-efficiency liquid-crystal-on-silicon light engines for augmented reality glasses

Opto-Electronic Advances, Год журнала: 2024, Номер 7(10), С. 240039 - 240039

Опубликована: Янв. 1, 2024

In lightweight augmented reality (AR) glasses, the light engines must be very compact while keeping a high optical efficiency to enable longtime comfortable wearing and ambient contrast ratio. "Liquid-crystal-on-silicon (LCoS) or micro-LED, who wins?" is recently heated debate question. Conventional LCoS system facing tremendous challenges due its bulky illumination systems; it often incorporates polarizing beam splitter (PBS) cube. To minimize formfactor of an system, here we demonstrate ultracompact consisting in-coupling prism, guide plate with multiple parallelepiped extraction prisms. The overall module volume including optics panel (4.4-μm pixel pitch 1024x1024 resolution elements), but excluding projection optics, merely 0.25 cc (cm3). Yet, our exhibits excellent illuminance uniformity impressive (36%–41% for polarized input light). Such high-efficiency expected revolutionize next-generation AR glasses.

Язык: Английский

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High-efficiency RGB achromatic liquid crystal diffractive optical elements

Opto-Electronic Advances, Год журнала: 2025, Номер 0(0), С. 240181 - 240181

Опубликована: Янв. 1, 2025

Liquid crystal Pacharatnam-Berry phase optical elements (PBOEs) have found promising applications in augmented reality and virtual because of their slim formfactor, lightweight, high efficiency. However, chromatic aberration remains a serious longstanding problem for diffractive optics, hindering broader adoption. To overcome the aberrations red, green blue (RGB) light sources, this paper, we propose counterintuitive multi-twist structure to achieve narrowband PBOEs without crosstalk, which plays vital role eliminate aberration. The performance our designed fabricated lenses (PBLs) aligns well with simulation results. Furthermore, feasibility demonstration experiment using laser projector, proposed PBL system indeed exhibits diminished as compared broadband PBL. Additionally, polarization raytracing is implemented demonstrate versatility designing any RGB wavelengths contrast ratios. This analysis explores lines quantum dot light-emitting diodes. Overall, approach enables efficiency, low fabrication complexity, degree design freedom accommodate liquid material holding immense potential widespread achromatic PBOEs.

Язык: Английский

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Breaking the optical efficiency limit of virtual reality with a nonreciprocal polarization rotator

Opto-Electronic Advances, Год журнала: 2024, Номер 7(3), С. 230178 - 230178

Опубликована: Янв. 1, 2024

A catadioptric lens structure, also known as pancake lens, has been widely used in virtual reality (VR) displays to reduce the formfactor. However, utilization of a half mirror (HM) fold optical path thrice leads significant loss. The theoretical maximum efficiency is merely 25%. To transcend this constraint while retaining foldable characteristic inherent traditional optics, paper, we propose theoretically lossless folded system replace HM with nonreciprocal polarization rotator. In our feasibility demonstration experiment, commercial Faraday rotator (FR) and reflective polarizers lossy HM. predicted 100% can be achieved approximately by using two high-extinction-ratio polarizers. addition, evaluated ghost images micro-OLED panel imaging system. Indeed, suppressed undetectable level if optics are antireflection coating. Our novel holds great potential for revolutionizing next-generation VR lightweight, compact formfactor, low power consumption.

Язык: Английский

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Broadband beam collimation metasurface for full-color micro-LED displays

Optics Express, Год журнала: 2024, Номер 32(6), С. 10252 - 10252

Опубликована: Фев. 23, 2024

Near-eye displays are widely recognized as a groundbreaking technological advancement with the potential to significantly impact daily life. Within realm of near-eye displays, micro-LEDs have emerged highly promising technology owing their exceptional optical performance, compact form factor, and low power consumption. However, notable challenge in integrating into is efficient light collimation across wide spectrum range. In this paper, we propose what believe be novel design broadband beam metasurface for full-color by harnessing wavefront phase modulation based on Huygens' principle. Our results demonstrate substantial reduction full width at half maximum (FWHM) angles, achieving 1/10, 1/20 red, green, blue compared those without metasurface, which best result far know. The central intensity increases 24.60, 36.49, 42.15 times. Furthermore, significant enhancement energy within ±10° achieved, respective multiplication factors 14.16, 15.60, 13.00. This has revolutionize field enabling high-performance, compact, lightweight micro-LED applications micro-projectors, beyond.

Язык: Английский

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Waveguide-based augmented reality displays: a highlight

Light Science & Applications, Год журнала: 2024, Номер 13(1)

Опубликована: Янв. 18, 2024

Abstract Augmented reality (AR), which emerged in the 1960s, remains a focal point of interest given its capacity to overlay real world with digitally presented information through optical combiners. The prevalent combiner, commonly known as waveguide AR literature, is prized for compact design and generous eyebox—essential elements human-centric technology. Nonetheless, these combiners encounter unique challenges meeting various other requirements human visual system. This paper highlights recent review technological advancements presents forward-looking perspective on future

Язык: Английский

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Applications and effectiveness of augmented reality in safety training: A systematic literature review and meta-analysis

Safety Science, Год журнала: 2024, Номер 178, С. 106624 - 106624

Опубликована: Июль 26, 2024

Язык: Английский

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Recent Applications of Optical Elements in Augmented and Virtual Reality Displays: A Review

ACS Applied Optical Materials, Год журнала: 2024, Номер 2(7), С. 1247 - 1268

Опубликована: Май 2, 2024

Augmented reality (AR) and virtual (VR) are emerging as a next-generation display platform, surpassing conventional flat panel displays. The AR/VR technologies garnering considerable attention from both industry academia they provide immersive user experiences smooth interaction between the real digital worlds. current displays, however, still face several challenges including limited field of view, small eye-box, conflict vergence accommodation, bulky form factor, heavy weight. This paper aims to comprehensive view optical elements emphasizing how enhance performance experience Various techniques explained in following two principal aspects: displays based on (1) holographic metasurfaces, (2) combined usage elements. In each section, characteristics principles components briefly explained. Then, their recent applications addressing limitations introduced.

Язык: Английский

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