US Patent 10237509 Systems with keyboards and head-mounted displays

A system may be provided in which input is gathered from a user with input-output devices. The input-output devices may include physical keyboards, touch screen displays, data gloves, and other input-output devices. Control circuitry in the system may use a head-mounted display, a display on a keyboard, and a display in a tablet computer or other electronic device to display images. Virtual reality content may be presented to a user with the head-mounted display. The virtual reality content may include virtual documents with virtual text, virtual keyboards with virtual keys, and other virtual objects. A virtual keyboard may be overlaid on top of a physical keyboard or on top of a keyboard display or touch screen display in a tablet computer or other electronic device. Virtual key labels may be updated in response to user key press input and other input.