PenSight: Enhanced Interaction with a Pen-Top Camera

We propose mounting a downward-facing camera above the top end of a digital tablet pen. This creates a unique and practical viewing angle for capturing the pen-holding hand and the immediate surroundings which can include the other hand. The fabrication of a prototype device is described and the enabled interaction design space is explored, including dominant and non-dominant hand pose recognition, tablet grip detection, hand gestures, capturing physical content in the environment, and detecting users and pens. A deep learning computer vision pipeline is developed for classification, regression, and keypoint detection to enable these interactions. Example applications demonstrate usage scenarios and a qualitative user evaluation confirms the potential of the approach.