Universal Access for the Partially Sighted Using Scanned Retinal Displays

由PI及其同事开发的虚拟视网膜显示器（VRD）通过以光栅模式扫描视网膜上的非相干或相干光来创建图像，而不是使用传统的图像平面屏幕。 VRD具有全彩色和宽亮度范围，即使在明亮的环境日光下也能实现高对比度;该机制最终将被小型化，以适应眼镜架，使可穿戴显示器成为可能。 由于这些属性，以及VRD参数可以以各种组合来配置以改变感知图像的特性（诸如视场、分辨率和扫描孔径的尺寸）的事实，VRD对于增强部分视力的视力具有很大的希望。 本研究的目标是研究如何最好地实现这一承诺。 VRD的小出射光瞳允许具有角膜变形和/或透镜的部分不透明（例如白内障）的用户看到清晰的图像。 对于黄斑变性等中央视网膜疾病，VRD可配置为将高对比度、大特征图像引导至周边视网膜。 对于只有一个小的中心区域可以保持功能的外周疾病，显示器可以配置有高分辨率的窄视场。 部分视力丧失受试者的初步测试表明，即使是VRD的非优化图像通常也比CRT图像更好。 PI将对部分视力用户进行心理物理视觉测试，并与标准计算机显示器（CRT和LCD）进行系统比较，以确定各种视觉障碍的适当VRD扫描和调制特性，以实现最佳图像分辨率、对比敏感度、颜色感知和无闪烁。 还将评估用户查看文本、观看视频图像和使用文字处理器、电子表格和网络浏览器等常见计算机应用程序的能力。 期望这项研究将最终导致新的视觉显示产品和技术，以提高计算机访问的低视力的人，包括不断增长的老年人口

The Virtual Retinal Display (VRD) developed by the PIs and their colleagues creates an image by scanning non-coherent or coherent light across the retina in a raster pattern, rather than using a conventional image plane screen. The VRD has full color and a broad luminance range for high contrast, even in bright ambient daylight; the mechanism will eventually be miniaturized to fit on a spectacle frame, making wearable displays feasible. Because of these attributes, and the fact that VRD parameters can be configured in various combinations to alter characteristics of the perceived image such as field of view, resolution and the size of the scanning aperture, the VRD holds great promise for enhancing vision in the partially sighted. The goal of this research is to investigate how best to realize this promise. The small exit pupil of the VRD allows clear images to be seen by users with corneal distortions and/or partial opacities of the lens such as cataracts. For central retinal diseases such as macular degeneration, the VRD can be configured to direct high contrast, large feature images to the peripheral retina. For peripheral disorders, where only a small central area may remain functional, the display can be configured with a high-resolution narrow field of view. Pilot tests of subjects with partial loss of vision indicate that even non-optimized images from the VRD can usually be seen better than CRT images. The PIs will conduct psychophysical visual testing with partially sighted users, and systematic comparison with standard computer displays (CRTs and LCDs), to determine for a variety of visual disorders the appropriate VRD scanning and modulation characteristics for optimal image resolution, contrast sensitivity, color perception and absence of flicker. The ability of users to view text, see video images and use common computer applications such as word processors, spreadsheets, and web browsers will also be assessed. The expectation is that this research will ultimately lead to new visual display products and techniques to enhance computer access for people with low vision, including the growing elderly population