1. Introduction

"Virtual Reality" has been a media buzzword for a number of years. A rather distorted perception of what "VR" means has been integrated into popular culture, leading to some fantastical expectations for the application of the actual technology. One group of VR researchers plotted the frequency with which the term "virtual reality" appeared in the press from 1989 through 1993 and found that the usage of those words was growing exponentially (Biocca, Kim, & Levy 1995).

In reality, a large body of knowledge about virtual environment (VE) systems remains to be explored before any realistic simulated "world" can be developed. In particular, a program of rigorous experimentation should be based upon the study of human perception and psychophysics. In this manner, new and unusual phenomenon resulting from the development of VE systems can be understood.

One important component of a successful virtual environment is the perception of depth. Depth perception is needed so that a user may develop a sense of "being there" in a virtual world. Unfortunately, the deficiencies of the displays in VE systems present a number of problems for accurate presentation of depth. Combating the limitations of these displays is a formidable job, especially for situations in which completing a particular task requires a presentation with substantial realism.

On to next section: Background