Viewing model for stereoscopic head-mounted displays

We characterize a class of stereoscopic displays, which includes head-mounted displays that incorporate miniature cathode-ray tubes. We present a detailed viewing model that accounts for the placement, size, and orientation of the virtual display images. The model is appropriate for several types of head-mounted display, as well as head-tracked stationary displays. The tracking algorithm accounts for the displacement between the tracking sensor and the user's eyes. We provide algorithms for calculating stereoscopic viewing and projection matrices. The algorithms are presented as parameterized homogeneous transforms. We also discuss design guidelines for avoiding accommodation/convergence conflicts, and managing the perceived field-of-view. The advantages of this viewing model and algorithm are the elimination of possible vertical parallax, and an undistorted perception of depth. Both of these factors can contribute to improved utility for the operator.