Extended reality (XR) is evolving into a general-purpose computing platform, yet its adoption for productivity is hindered by visual fatigue and simulator sickness. While these symptoms are often attributed to latency or motion conflicts, the precise impact of textual clarity on physiological comfort remains undefined. Here we show that sub-optimal effective resolution, the clarity that reaches the eye after the full display-optics-rendering pipeline, is a primary driver of simulator sickness during reading tasks in both virtual reality and video see-through environments. By systematically manipulating end-to-end effective resolution on a unified logMAR scale, we measured reading psychophysics and sickness symptoms in a controlled within-subjects study. We find that reading performance and user comfort degrade exponentially as resolution drops below 0 logMAR (normal visual acuity). Notably, our results reveal 0 logMAR as a key physiological tipping point: resolutions better than this threshold yield naked-eye-level performance with minimal sickness, whereas poorer resolutions trigger rapid, non-linear increases in nausea and oculomotor strain. These findings suggest that the cognitive and perceptual effort required to resolve blurry text directly compromises user comfort, establishing human-eye resolution as a critical baseline for the design of future ergonomic XR systems.

翻译：扩展现实（XR）正在演变为通用计算平台，但其在生产力应用中的普及受到视觉疲劳和模拟器不适的阻碍。虽然这些症状常被归因于延迟或运动冲突，但文本清晰度对生理舒适度的具体影响尚未明确。本文证明，次优的有效分辨率——即经过完整显示-光学-渲染管线后抵达眼睛的清晰度——是虚拟现实与视频透视环境中阅读任务引发模拟器不适的主要驱动因素。通过在对数最小分辨角统一尺度上系统操控端到端有效分辨率，我们在受控的受试者内研究中测量了阅读心理物理学指标与不适症状。研究发现，当分辨率低于0 logMAR（正常视力水平）时，阅读表现与用户舒适度呈指数级下降。值得注意的是，我们的结果揭示0 logMAR是关键生理临界点：优于该阈值的分辨率可实现裸眼级表现且不适感最小，而低于该阈值的分辨率则会引发恶心与眼动负荷的快速非线性增长。这些发现表明，解析模糊文本所需的认知与感知努力直接损害用户舒适度，从而确立人眼分辨率作为未来人机工程学XR系统设计的关键基准。