Abstract Visual field defect (VFD) is a type of ophthalmic disease that causes the loss of part of the patient’s field of view (FoV). In this paper, we propose a method to enlarge the restricted FoV with an optical see-through head-mounted display (OST-HMD) equipped with a camera that captures an overview and overlays it on the persisting FoV. Because the overview window occludes the real background scene, it is important to create a balance between the augmented contextual information and the unscreened local information. We recruited twelve participants and conducted an experiment to seek the best size, position, and opacity for the overview window through a Whac-A-Mole task (a touchscreen game). We found that the performance was better when the overview window was of medium size (FoV of 9.148∘ × 5.153∘, nearly one third of FoV of the used OST-HMD) and placed lower in the visual field. Either too large or too small a size decreases the performance. The performance increases with increased opacity. The obtained results can legitimate the default setting for the overview window.

中文翻译：

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使用概览窗口提高偏盲患者的视觉表现

摘要 视野缺损 (VFD) 是一种导致患者部分视野 (FoV) 丧失的眼科疾病。在本文中，我们提出了一种使用光学透视头戴式显示器 (OST-HMD) 放大受限 FoV 的方法，该显示器配备了一个摄像头，可捕获概览并将其叠加在持续的 FoV 上。由于概览窗口遮挡了真实的背景场景，因此在增强的上下文信息和未筛选的本地信息之间建立平衡很重要。我们招募了 12 名参与者并进行了一项实验，以通过 Whac-A-Mole 任务（触摸屏游戏）寻找概览窗口的最佳尺寸、位置和不透明度。我们发现当概览窗口为中等大小（FoV 为 9.148∘ × 5.153∘，使用的 OST-HMD 的近三分之一的 FoV）并放置在视野中的较低位置。尺寸太大或太小都会降低性能。性能随着不透明度的增加而增加。获得的结果可以使概览窗口的默认设置合法。