The Implications of Interpupillary Distance Variability for Virtual Reality

Creating and presenting binocular images for virtual reality and other 3D displays needs to take account of the interpupillary distance-the distance between the user's eyes. While VR headsets allow for some adjustments of this setting, this does not accommodate the full range found in the population, and may not necessarily be accurately measured and adjusted in practice. A mismatch between the observer's IPD and that assumed in creating and presenting stimuli will tend to cause problems with viewing comfort and accurate depth perception. We identify unnatural eye fixations, visual discomfort and inaccurate depth perception as important considerations for understanding the suitability of VR for use by children. We present a geometrical quantification of each of these factors.