Depth Perception Within Virtual Environments: Comparison Between two Display Technologies

Depth perception is one of the key issues in virtual reality. Many questions within this area are still under investigation including the egocentric distance misestimation. In this paper we describe an experiment confirming distance underestimation from another point of view. The approach we developed is based on a very simple task: subjects had to compare relative depths of two virtual objects. The experiment compared performance using head mounted display and stereoscopic widescreen display to evaluate which visual cues subjects use to estimate depth of virtual objects. To minimize motoric effects, subjects were seated and their estimations were only verbal. Likewise, to avoid the well known effects of apparent size, namely the size-distance invariance, the experiment was also performed with conflict sequences: the presented objects had the same apparent sizes with different depths or the same depth but different physical sizes. The obtained results show significant differences between the two devices and confirm the distance misestimation phenomenon for head mounted display. Moreover, changing the background color or the shape of the presented objects also had an influence on subjects’ performance. Keywords-Virtual reality, Human-machine interaction, Cognition, Depth perception, Head mounted display, Widescreen display.