A Head Mounted Display Without Focus/Fixation Disparity

This small Business Innovation Research Phase I Project will investigate a method of eliminating the focus/fixation disparity in a head mounted display. The disparity between focus and fixation points in head mounted stereoscopic viewing systems often creates a problem for the viewer in terms of eyestrain, defocused images, or inability to fuse images. Such problems show up most when objects are represented across a wide range of distances from the user, or when the system is used to superimpose virtual information onto real world scenes. Past attempts at matching the focus and fixation distance in head mounted displays have involved complicated servo mechanisms and eye trackers to change the apparent distance to the screen as the observer gazes at different areas of the scene. This proposed project will demonstrate a novel, less complicated way of creating images in which the focus and fixation distances are matched for objects from several inches to infinity without using eye tracking, measuring equipment, or moving parts. The proposed device will create several convergent ray bundles for each displayed image point in such a way that the bundles all intersect to form a light point at a distance that is coincident with the fixation distance.