Opt Express. 2021 Oct 11;29(21):33890-33914. doi: 10.1364/OE.440323.
A foveated display is a promising technique to realize displays offering both a large field of view (FOV) and high spatial resolution. Although several prior works have attempted to apply a foveation method to the design of a head-mounted display (HMD) system, the common method is based on a dual-resolution dynamic foveation scheme which is inevitably complex and has a high cost due to the requirements for multiple display sources, a 2D steering mechanism, and eye tracker. In this paper, a new perceptual-driven approach to the design of a statically foveated HMD is proposed with the goal of offering a wide FOV across which the degradation of the perceived image resolution is nearly imperceptible or minimal within regions of frequent eye movements. Compared to a dual-resolution discrete and dynamic foveation approach in the prior art, the static foveation approach will not only maintain resolution continuity but also eliminate the need for a scanning mechanism, multiple display sources, and an eyetracker, and therefore minimize hardware complexity. We present the general approach for creating a static foveation scheme, performance metrics for evaluating the perceived image quality, and the process of optimizing a foveation scheme to meet different requirements. Finally, we experimentally demonstrate and validate the proposed foveation scheme using a testbed system. Overall, we demonstrate a statically foveated scheme is capable of offering a display with a total 160° FOV, a constant resolution of 0.5 or 1 arcminutes per pixel within the ±10° region where frequent eye movements occur, an adequate resolution no less than 45% of peak resolution within the parafovea region of ±30°, and a data sampling efficiency as high as 90%.
注视点渲染是一种很有前景的技术,可以实现具有大视场(FOV)和高空间分辨率的显示。尽管之前已经有几项工作尝试将注视点方法应用于头戴式显示器(HMD)系统的设计中,但常见的方法是基于双分辨率动态注视点方案,由于需要多个显示源、2D 转向机制和眼动追踪器,该方案不可避免地复杂且成本高。在本文中,提出了一种新的基于感知的静态注视点 HMD 设计方法,目标是提供宽 FOV,在该视场中,在频繁眼动的区域内,感知图像分辨率的下降几乎不可察觉或最小。与之前艺术中的双分辨率离散和动态注视点方法相比,静态注视点方法不仅可以保持分辨率连续性,还可以消除对扫描机制、多个显示源和眼动追踪器的需求,从而最大限度地降低硬件复杂性。我们提出了创建静态注视点方案的一般方法、评估感知图像质量的性能指标,以及优化注视点方案以满足不同需求的过程。最后,我们使用测试平台系统对提出的注视点方案进行了实验演示和验证。总的来说,我们证明了静态注视点方案能够提供总 FOV 为 160°的显示,在频繁眼动发生的±10°区域内,每个像素的分辨率为 0.5 或 1 弧分,在±30°的旁区中,分辨率不低于峰值分辨率的 45%,数据采样效率高达 90%。