Abstract
In stereo displays, binocular disparity creates a striking impression of depth. However, such displays
present focus cues-blur and accommodation-that specify a different depth than disparity, thereby
causing a conflict. This conflict causes several problems including misperception of the 3D layout,
difficulty fusing binocular images, and visual fatigue. To address these problems, we developed a
display that preserves the advantages of conventional stereo displays, while presenting correct or
nearly correct focus cues. In our new stereo display each eye views a display through a lens that
switches between four focal distances at very high rate. The switches are synchronized to the
display, so focal distance and the distance being simulated on the display are consistent or nearly
consistent with one another. Focus cues for points in--between the four focal planes are simulated by
using a depth-weighted blending technique. We will describe the design of the new display, discuss
the retinal images it forms under various conditions, and describe an experiment that illustrates the
effectiveness of the display in maximizing visual performance while minimizing visual fatigue.
