Mixed Reality Tunneling Effects for Stereoscopic Untethered Video-See-Through Head-Mounted Displays

We present mixed reality (MR) tunneling, a novel method to balance the trade-off between limited render performance and high visual quality of video see-through head-mounted displays (VST-HMDs) through fusing images of two types of camera sensors with different resolutions and frame rates. By merging a color video stream from an external stereoscopic camera with the grayscale VST commonly integrated into today’s standalone virtual reality (VR) headsets, we create a perceptually high-resolution and wide field of view VSTHMD prototype. The external high-resolution VST displayed at the central foveal to the para-peripheral region of the human visual field complements the low-resolution, low-latency grayscale VST at the far peripheral region, producing a tunneling effect, which simulates the human foveal and peripheral vision, with the potential to reduce cybersickness as in the tunneling effect in immersive VR. We propose two extensions to the MR tunneling method. The first one accommodates the user’s head movement speed by fading out the external VST when fast head movements are detected, thus potentially compensating for video streaming latency. The second one is a foveated MR tunneling effect, which displays the center of the external VST based on the tracked user eye movements. We evaluated the three MR tunneling methods in a within-subject study with 24 participants. The user study demonstrates the potential of our prototype and techniques based on the example of an assembly task that requires hand-eye coordination, untethered locomotion, and fine motor skills. The results demonstrate that, although not significant, the MR tunneling effects lead to higher overall usability, less perceived motion sickness, and a better sense of presence. ¹