ItemGoing Blank Comfortably: Positioning Monocular Head-Worn Displays When They are Inactive(ACM, 2023-10) Song, Yukun; Arora, Parth; Singh, Rajandeep; Varadharajan, Srikanth; Haynes, Malcolm; Starner, ThadHead-worn displays like Tooz and North’s Focals are designed to be worn all day as smart eyeglasses. When the display is not lit (often to save battery life), the optical combiners may remain visible to the user as an out-of-focus seam or discoloration in the lens. We emulate seven shapes and positions of optical combiners which 30 participants rank for comfort. Based on these results, we run a second user study with 12 participants comparing the comfort of a combiner with various offset distances from the user’s primary position of gaze (PPOG) towards the nose. Results suggest that a combiner’s nearest edge should be more than 15° from the PPOG.