Occlusion

In the context of touchscreen and pen-based interaction, occlusion refers to the user's hand or finger blocking their view of content on the screen while interacting with it. Occlusion is a significant accessibility barrier, particularly for older adults and users with motor impairments, as it can prevent users from seeing what they are selecting, obscure feedback about their actions, and cause unintended interactions when the hand moves to reveal hidden content. Design strategies to mitigate occlusion include shifting interactive elements away from the touch point, providing visual feedback above the finger/pen, adapting layouts based on handedness, and using hover previews or magnification lenses.