Understanding and Enhancing Visual Perception in Virtual Reality

The visual perception in virtual reality head-mounted displays (VR HMDs) is influenced by multiple factors, including refresh rate, display resolution, frame rate, render resolution, and the optical system. These elements are complex and interrelated, often requiring comprehensive technical knowledge to fully understand their impact on VR visual perception. Existing methods for evaluating VR visual perception are often prohibitively expensive for academic use and VR users. However, understanding and optimizing these factors is crucial for enhancing user experience, reducing simulator sickness, and improving user performance in VR environments. This thesis explores various methodologies to understand and enhance visual perception in VR by conducting four distinct studies. Firstly, empirical user study on the effect of render resolution were carried out to examine how different render resolutions impact gameplay experience, performance, and simulator sickness in VR games. Secondly, empirical user study on the effect of frame rate were performed to investigate how varying frame rates influence user experience, performance, and simulator sickness, considering both gamer perspectives and basic visual perception during saccades. Thirdly, a novel visual acuity test was adapted to measure the end-to-end visual clarity in VR, introducing the concept of Omnidirectional Virtual Visual Acuity (OVVA) as a new metric for evaluating and understanding visual clarity in VR systems. Lastly, visual acuity, contrast sensitivity, and color vision tests were adapted for evaluating the visual perception of VR passthrough, establishing a comprehensive benchmark to assess the visual perception capabilities of Video See-Through (VST) HMDs. Our approaches suggest that there are feasible, low-cost methods for assessing important aspects of visual perception in VR, which could democratize the evaluation process and accelerate the development of high-quality VR HMDs. Our research demonstrates that vision-oriented VR research and development is an efficient approach to comprehending and improving visual perception in VR. The findings provide valuable insights and practical guidelines for developers and researchers aiming to optimize VR systems for better user engagement and comfort. This work also addresses the information asymmetry between manufacturers and users, offering a clearer understanding of VR visual performance and guiding future advancements in VR technology.