Positioning Monocular Optical See Through Head Worn Displays in Glasses for Everyday Wear

Head-worn displays for everyday wear in the form of regular eyeglasses are technically feasible with recent advances in waveguide technology. One major design decision is determining where in the user's visual field to position the display. Centering the display in the principal point of gaze (PPOG) allows the user to switch attentional focus between the virtual and real images quickly, and best performance often occurs when the display is centered in PPOG or is centered vertically below PPOG. However, these positions are often undesirable in that they are considered interruptive or are associated with negative social perceptions by users. Offsetting the virtual image may be preferred when tasks involve driving, walking, or social interaction. This paper consolidates findings from recent studies on monocular optical see-through HWDs (OST-HWDs), focusing on potential for interruption, comfort, performance, and social perception. For text-based tasks, which serve as a proxy for many monocular OST-HWD tasks, we recommend a 15{\deg} horizontal field of view (FOV) with the virtual image in the right lens vertically centered but offset to +8.7{\deg} to +23.7{\deg} toward the ear. Glanceable content can be offset up to +30{\deg} for short interactions.