Stereoscopic retinal scanning laser display with integrated focus cues for ocular accommodation

摘要

We describe a full-color stereoscopic display that varies the focus of objects at different distances in a displayed scene to match vergence and stereoscopic retinal disparity demands, better approximating natural vision. In natural vision, the oculomotor processes of accommodation (eye focus) and vergence (angle between lines of sight of two eyes) are reflexively linked such that a change in one drives a matching change in the other. Conventional stereoscopic displays require viewers to decouple these processes, and accommodate at a fixed distance while dynamically varying vergence to view objects at different stereoscopic distances. This decoupling generates eye fatigue and compromises image quality when viewing such displays. In contrast, our display overcomes this cue conflict by using a deformable membrane mirror to dynamically vary the focus of luminance-modulated RGB laser beams before they are raster-scanned and projected directly onto the retina. The display has a large focal range (closer than the viewer's near point to infinity) and presents high-resolution (1280x480) full-color images at 60 Hz. A viewer of our display can shift accommodation naturally from foreground to background of a stereo image, thereby bringing objects at different distances into and out of focus. Design considerations and human factors data are discussed.