Fisheye vision: Peripheral spatial compression for improved field of view in head mounted displays

A current problem with many video see-through displays is the lack of a wide field of view, which can make them dangerous to use in real world augmented reality applications since peripheral vision is severely limited. Existing wide field of view displays are often bulky, lack stereoscopy, or require complex setups. To solve this problem, we introduce a prototype that utilizes fisheye lenses to expand a user's peripheral vision inside a video see-through head mounted display. Our system provides an undistorted central field of view, so that natural stereoscopy and depth judgment can occur. The peripheral areas of the display show content through the curvature of each of two fisheye lenses using a modified compression algorithm so that objects outside of the inherent viewing angle of the display become visible. We first test an initial prototype with 180° field of view lenses, and then build an improved version with 238° lenses. We also describe solutions to several problems associated with aligning undistorted binocular vision and the compressed periphery, and finally compare our prototype to natural human vision in a series of visual acuity experiments. Results show that users can effectively see objects up to 180°, and that overall detection rate is 62.2% for the display versus 89.7% for the naked eye.