Apple has filed for a patent
that the improves the overall functionality of a stylus.
According to the patent, the "Active Stylus" includes an electrode at a tip of the stylus; and powered circuitry coupled to the electrode and configured for capacitively coupling the electrode with a capacitive touch sensor panel. The powered circuitry can further include drive circuitry configured to output a drive voltage at the electrode and/or sense circuitry configured to sense a voltage received at the electrode.
The patent generally relates to a stylus that can act as a drive and/or a sense element in a capacitive touch system. Unlike conventional styluses which work passively by blocking electric field lines between the drive and sense electrodes of a capacitive touch sensor panel, the styluses disclosed in the patent can either act as a drive electrode to create an electric field between the drive electrode and the sense lines of a mutual capacitive touch sensor panel, or as a sense electrode for sensing capacitively coupled signals from one or more stimulated drive rows and columns of the touch sensor panel or both. Accordingly, the styluses can be referred to as active styluses in comparison to conventional passive styluses. According to Samsung, these active styluses can improve stylus sensing on a mutual capacitive touch sensor panel without incurring significant additional cost.
The patent application does not mention Apple. However, the two men filing for it -- Jonah Harley and David Simon -- are both engineering managers at the company.
Apple's late co-founder Steve Jobs often scoffed at the stylus during his tenure as chief executive. On several occasions, Jobs said that he believed a stylus bundled with a product meant it was a failed device.