Geometric transformations for displaying virtual objects on stereoscopic devices

Undistorted through-the-window (i.e. behind the projection screen) stereograms can be generated by using the stereoscopic window projection technique on CRT based flat projection screens. Widely used graphics libraries like Silicon Graphics GL afford the direct implementation of this technique. Physiological concerns may demand the display of the virtual object in front of the projection screen. Here we discuss the problems related to displaying front-screen undistorted stereograms using Silicon Graphics GL. We show that the spatial resolution achievable with front-screen stereograms is better than that typical of through-the-window stereograms. Furthermore we characterize analytically the physical volume in which Virtual objects can be displayed. (C) 1997 Elsevier Science Ltd.