Several experiments have provided evidence that ego-centric distances are perceived as compressed in immersive virtual environments relative to the real world. The principal factors responsible for this phenomenon have remained largely unknown. However, recent experiments suggest that when the virtual environment (VE) is an exact replica of a user’s real physical surroundings, the person’s distance perception improves. Furthermore, it has been shown that when users start their virtual reality (VR) experience in such a virtual replica and then gradually transition to a different VE, their sense of presence in the actual virtual world increases significantly. In this case the virtual replica serves as a transitional environment between the real and virtual world. In this paper we examine whether a person’s distance estimation skills can be transferred from a transitional environment to a different VE. We have conducted blind walking experiments to analyze if starting the VR experience in a transitional environment can improve a person’s ability to estimate distances in an immersive VR system. We found that users significantly improve their distance estimation skills when they enter the virtual world via a transitional environment. CR Categories: H.5.1 [Information Interfaces and Presentation]: Multimedia Information Systems—Artificial, augmented, and virtual realities Virtual reality, distance estimation, transitional envi-Keywords: ronment

Virtual environment (VE) technology has great potential to enhance the ability for people to perceive and interact with computer simulated environments. Ideally, people would perceive and interact with the virtual world the same way that they would a real environment. Subjective experience and empirical research, however, show that there are significant differences between real and virtual environments. My primary research goal is to understand why these differences exist and how they can be reduced or eliminated. Research in this area is an inherently multidisciplinary task that involves both computer science and psychology. Significant technical knowledge is required to properly construct an accurate simulation of an environment. In addition, head and body tracking are required for a user to be able to naturally view and locomote through an environment. After an accurate virtual environment is created, expertise in psychology is required to construct experiments to quantitatively measure differences between how people perceive and act in real and virtual environments. Since virtual environments give researchers complete control over the visual information presented to users, psychologists are also interested in using the technology to perform experiments that are not possible or practical in the real world. If differences between real and virtual worlds can be eliminated, virtual environments

Most head-mounted displays (HMDs) suffer from substantial optical distortion, and vendor-supplied specifications for field-of-view often are at variance with reality. Such displays do not present perspective-related visual cues in a geometrically correct manner, which has the potential to affect applications of HMDs which depend on precise spatial perception. This paper provides empirical evidence for the degree to which these resulting distortions affect one type of spatial judgment in virtual environments. We show that minification in the HMD that would occur from an overstated HMD field of view results in a significant change in distance judgments. Incorrectly calibrated pitch and pincushion distortion, however, did not cause statistically significant changes in distance judgments for the degree of distortions examined. While the means for determining the optical distortion of display systems are well known, they are often not used in non-see-through HMDs due to problems in measuring and correcting for distortion. As a result, we also provide practical guidelines for creating geometrically calibrated systems.

doi:10.1111/j.1460-9568.2010.07212.x The brain weights body-based cues higher than vision when estimating walked distances