Effect of half-occluded region on human recognition of a mirror

This paper addresses the differences between conventional optical mirrors and electrical mirrors consisting of a camera and a flat display panel. Recently, vehicle mirrors (side-view and rear-view mirrors) are gradually being replaced with electrical mirrors (i.e., display devices). The characteristics of electrical mirrors are different from those of conventional mirrors in many aspects. These differences can cause an uncomfortable feeling in drivers. In this paper, we focus on the half occlusion appearing in the peripheral areas of a display and investigate the effects of half-occluded regions on whether humans recognize a viewing device as a mirror. To evaluate this effect, we conducted experiments based on pairwise comparisons using a head-mounted display (HMD) to present virtual mirror objects having different characteristics in terms of half occlusion as well as binocular and motion parallaxes. Experimental results suggest that half occlusion is certainly related to the human recognition of a mirror. Furthermore, pseudo half-occlusions introduced by barriers in front of a 2D display can reinforce this recognition.