Ultracompact and high-efficiency liquid-crystal-on-silicon light engines for augmented reality glasses
应用于增强现实眼镜的超紧凑高效硅基液晶光引擎
リアルメガネを強化する超コンパクトで高効率なシリコンベース液晶光エンジン
증강현실 안경을 위한 초소형 고효율 실리콘 기반 액정광 엔진
Motor de luz LCD de silicio ultracompacto y eficiente para gafas de realidad aumentada
Moteur optique LCD ultra - compact et efficace à base de silicium pour lunettes de réalité augmentée
Сверхкомпактный высокоэффективный жидкокристаллический световой двигатель на основе кремния для очков дополненной реальности
¹ College of Optics and Photonics, University of Central Florida, Orlando FL 32816, USA
² Meta Reality Labs, 9845 Willows Road NE, Redmond, WA 98052, USA
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 high ambient contrast ratio. “Liquid-crystal-on-silicon (LCoS) or micro-LED, who wins?” is recently a heated debate question.
Conventional LCoS system is facing tremendous challenges due to its bulky illumination systems; it often incorporates a bulky polarizing beam splitter (PBS) cube. To minimize the formfactor of an LCoS system, here we demonstrate an ultracompact illumination system consisting of an in-coupling prism, and a light guide plate with multiple parallelepiped extraction prisms.
The overall module volume including the illumination optics and an LCoS panel (4.4-μm pixel pitch and 1024x1024 resolution elements), but excluding the projection optics, is merely 0.25 cc (cm³). Yet, our system exhibits an excellent illuminance uniformity and an impressive optical efficiency (36%–41% for a polarized input light). Such an ultracompact and high-efficiency LCoS illumination system is expected to revolutionize the next-generation AR glasses.
