Moving Towards Consistent Depth Perception in Stereoscopic Projection-based Augmented Reality

Abstract

Stereoscopic projection-based augmented reality (AR) is a promising technology for creating an effective illusion of virtual and real objects coexisting within the same space. By using projection technology, two-dimensional (2D) textures as well as three-dimensional (3D) virtual objects can be displayed on arbitrary physical objects. However, depending on the geometry of the projection surface, even a single virtual object could be projected with varying depths, orientations, and forms. For these reasons, it is an open question whether or not a geometrically-correct projection leads to a consistent depth perception of the AR environment. We performed an experiment to analyze how humans perceive depths of objects that are stereoscopically projected at different surfaces in a projection-based AR environment. In a perceptual matching task the participants had to adjust the depth of one of two visual stimuli, which were displayed at different depths with varying parallaxes, until they estimated the depths of both stimuli to match. The results indicate that the effect of parallax on the estimation of matching depths significantly depends on the participant's experience with stereoscopic display. Regular users were able to match the depths of both stimuli with a mean absolute error of less than one centimeter, whereas less experienced users made errors in the range of more than 2cm on average. We performed a confirmatory study to verify our findings with more ecologically valid projection-based AR stimuli.