Universal Access for the Partially Sighted Using Scanned Retinal Displays

由pi和他们的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；该装置最终将被小型化，以适应眼镜框架，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配置来改变感知图像的特征，如视野、分辨率和扫描孔径的大小，VRD在增强部分视力者的视力方面具有很大的希望。本研究的目的是探讨如何最好地实现这一承诺。VRD的小出口瞳孔可以让患有角膜变形和/或部分晶状体混浊（如白内障）的用户看到清晰的图像。对于黄斑变性等中枢性视网膜疾病，VRD可以配置为将高对比度的大特征图像直接显示在外周视网膜。对于外围疾病，只有一个小的中心区域可能保持功能，显示器可以配置一个高分辨率的窄视野。对部分视力丧失的受试者进行的初步测试表明，即使是来自VRD的非优化图像通常也比CRT图像看得更好。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，以确定适合各种视觉障碍的VRD扫描和调制特性，以获得最佳图像分辨率、对比度灵敏度、色彩感知和无闪烁。用户查看文本、观看视频图像和使用普通计算机应用程序（如文字处理器、电子表格和网络浏览器）的能力也将被评估。人们期望这项研究最终将带来新的视觉显示产品和技术，以增强低视力人群（包括日益增长的老年人口）对计算机的访问

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