Asymmetric Lateral Field-of-View Restriction to Mitigate Cybersickness during Virtual Turns

Field-of-view (FOV) restriction is a common technique to reduce cybersickness in commercial virtual reality (VR) applications. However, the majority of existing FOV restriction techniques are implemented as symmetric imagery, which occludes users' views during virtual rotation. In this paper, we proposed and evaluated a novel variant of FOV restriction, referred to as a side restrictor. Side restriction uses an asymmetric mask to obscure only one side region of the periphery during virtual rotation and laterally shifts the center of restriction towards the direction of the turn. We conducted a study using a between-subjects design that compared the side restrictor, a traditional symmetric restrictor, and a control condition without FOV restriction. Participants were required to navigate through a complex maze-like environment using a controller using one of three restrictors. Compared to the control condition, the side restrictor was effective in mitigating cybersickness, reducing discomfort, improving subjective visibility, and enabling users to remain immersed for a longer period of time. Additionally, we found no empirical evidence of negative drawbacks when compared to the symmetric restrictor, which suggests that side restriction is an effective cybersickness mitigation technique for virtual environments with frequent turns.