A Novel Proposal of a Magnification-Rate Function for Aligning Size Perception Between Virtual Reality and Physical Space

Head-mounted displays, which are commonly used to experience virtual reality spaces, utilize the binocular disparity. It has been pointed out that the size of objects perceived in virtual reality space does not necessarily match the size perceived in physical space. This discrepancy is thought to arise from differences in depth cues used in virtual reality space and physical space, even when head-mounted displays are employed. To date, as one method for resolving this discrepancy, an image generation technique has been proposed in which the size of objects in virtual reality space is enlarged or reduced while considering size perception in physical space. In this approach, a magnification-rate function that represents the relationship between the distance to an object and its perceived size is used. The purpose of this study is to experimentally investigate the relationship of perceived size in virtual reality space and to propose a refined magnification-rate function that does not depend on a reference distance. By generating images in accordance with the proposed magnification-rate function, this study aims to enable users to experience a virtual reality space that closely resembles the sense of size perceived in physical space. The proposed magnification-rate function provides a theoretical interpretation of the empirically derived magnification-rate function from the viewpoint of size constancy. Moreover, it shows that the proposed function is more general and independent of the reference distance.