SYSTEM AND METHOD OF COMMUNICATION BETWEEN A CAPACITIVE TOUCH SCREEN AND AN ACTIVE STYLUS

摘要

An active stylus is capacitively coupled to a capacitive touch panel for communication. The active stylus operates in a wait mode to receive initial communications from the panel. In response to such receipt, the active stylus synchronizes to a repeating communications frame implementing time division multiplexing. Communications from the active stylus to the panel include: information communications; synchronization communications and communications specific for columns and/or rows of the panel. Communications from the panel to the active stylus may be addressed uniquely to the stylus or commonly to a group of styluses.

主权项

1. A method, comprising:
sending through a capacitive touch panel of a first signal during a first period of a repeating frame; receiving by an active stylus capacitively coupled to the capacitive touch panel of the first signal; sending by the active stylus of a second signal during a second period of said repeating frame; and receiving through the capacitive touch panel of the second signal.