Orthographic and perspective projection influences linear vection in large screen virtual environments

Abstract

Vection is defined as the visually induced illusion of self motion [Fischer and Kornmuller 1930]. Previous research has suggested that linear vection (the illusion of self-translation) is harder to achieve than circular vection (the illusion of self-rotation) in both laboratory settings (typically using 2D stimuli such as black and white stripes) [Rieser 2006] and virtual environment setups [Schulte-Pelkum 2007; Mohler et al. 2005]. In real a life situation when experiencing circular vection all objects rotate around the observer with the same angular velocity. For linear motion, however, the change in the oberver position results in a change in the observed position of closer objects with respect to farther away objects or the background. This phenomenon, motion parallax, provides pictorial depth cues as closer objects appear to be moving faster compared to more distant objects.