从导模理论看增强现实波导的角分辨率极限

中文摘要 AI 辅助

我们从导模理论推导了增强现实（AR）波导合束器的角分辨率极限。有限厚度的平板仅支持一组离散的全内反射（TIR）角，这导致角分辨率随波导变薄和TIR角减小而变差。在500微米厚度下，在大部分可用的TIR范围内，分辨率劣于1弧分（60 ppd）的视力目标，而要在TIR<42°时达到1弧分，则需要厚度超过1毫米的基底。该极限会被大于约0.1纳米的光源线宽或大于约100纳米的跨瞳孔复制周期的厚度变化所抹除，但仅会被瞳孔截断部分消除，且完全不受出耦合损耗影响。因此，基于LED和微型LED的显示器因其宽光谱而不受影响，而基于窄线宽激光的显示器在薄且均匀的波导中则受此极限约束。

英文摘要

We derive the angular resolution limit of an augmented-reality (AR) waveguide combiner from guided mode theory. A slab of finite thickness supports only a discrete set of total-internal-reflection (TIR) angles, giving an angular resolution that worsens with thinner waveguides and smaller TIR angles. At 500 $μ$m thickness the resolution is worse than the 1 arcmin (60 ppd) acuity target over most of the usable TIR range, and reaching 1 arcmin for TIR < 42$^\circ$ requires a substrate thicker than 1 mm. The limit is washed out by a source linewidth above $\sim$0.1 nm or a thickness variation above $\sim$100 nm across the pupil-replication period, but only partially by pupil truncation and not at all by out-coupling loss. LED- and micro-LED-based displays are therefore unaffected with their broad spectrum, whereas a narrow-linewidth laser-based display in a thin, uniform waveguide is subject to this limit.

发表机构

• Reality Labs, Meta（Meta现实实验室）

机构由 AI 辅助整理，请以论文原文为准。