Distance Perception in Virtual Environment through Head-mounted Displays

Head-mounted displays (HMDs) are popular and affordable wearable display devices which facilitate immersive and interactive viewing experience. Numerous studies have reported that people typically underestimate distances in HMDs. This dissertation describes a series of research experiments that examined the influence of FOV and peripheral vision on distance perception in HMDs and attempts to provide useful information to HMD manufacturers and software developers to improve perceptual performance of HMD-based virtual environments. This document is divided into two main parts. The first part describes two experiments that examined distance judgments in Oculus Rift HMDs. Unlike numerous studies found significant distance compression, our Experiment I & II using the Oculus DK1 and DK2 found that people could judge distances near-accurately between 2 to 5 meters. In the second part of this document, we describe four experiments that examined the influence of FOV and human periphery on distance perception in HMDs and explored some potential approaches of augmenting peripheral vision in HMDs. In Experiment III, we reconfirmed the peripheral stimulation effect found by Jones et al. using bright peripheral frames. We also discovered that there is no linear correlation between the stimulation and peripheral brightness. In Experiment IV, we examined the interaction between the peripheral brightness and distance judgments using peripheral frames with different relative luminances. We found that there exists a brightness threshold; i.e., a minimum brightness level that\u27s required to trigger the peripheral stimulation effect which improves distance judgments in HMD-based virtual environments. In Experiment V, we examined the influence of applying a pixelation effect in the periphery which simulates the visual experience of having a peripheral low-resolution display around viewports. The result showed that adding the pixelated peripheral frame significantly improves distance judgments in HMDs. Lastly, our Experiment VI examined the influence of image size and shape in HMDs on distance perception. We found that making the frame thinner to increase the FOV of imagery improves the distance judgments. The result supports the hypothesis that FOV influences distance judgments in HMDs. It also suggests that the image shape may have no influence on distance judgments in HMDs