US 11,874,974 B2
Differential sensing in an active stylus
Kishore Sundara-Rajan, San Jose, CA (US); Yassar Ali, Sunnyvale, CA (US); Igor Polishchuk, Fremont, CA (US); and James D. Lyle, Santa Clara, CA (US)
Assigned to Wacom Co., Ltd., Saitama (JP)
Filed by Wacom Co., Ltd., Saitama (JP)
Filed on Mar. 18, 2022, as Appl. No. 17/698,767.
Application 17/698,767 is a continuation of application No. 16/939,862, filed on Jul. 27, 2020, granted, now 11,301,060.
Application 16/939,862 is a continuation of application No. 13/434,596, filed on Mar. 29, 2012, granted, now 10,725,564, issued on Jul. 28, 2020.
Claims priority of provisional application 61/553,114, filed on Oct. 28, 2011.
Prior Publication US 2022/0206599 A1, Jun. 30, 2022
This patent is subject to a terminal disclaimer.
Int. Cl. G06F 3/0354 (2013.01); G06F 3/038 (2013.01)
CPC G06F 3/03545 (2013.01) [G06F 3/0383 (2013.01)] 8 Claims
OG exemplary drawing
 
1. A method comprising:
receiving, with a first electrode of a first device, a first signal comprising a signal component, the first device being operable to communicate wirelessly with a second device via the first electrode and through a sensor of the second device;
receiving a second signal from a second electrode of the first device, the second signal comprising a signal component, the first signal and second signal each containing noise having similar characteristics, and wherein the signal component of the first signal is a first version of a signal of the second device and the signal component of the second signal is a second version of the signal of the second device;
removing noise from the first signal by subtracting the second signal from the first signal, including generating an output that is the difference between the first signal and the second signal; and
determining the signal component of the first signal based on the output and the signal component of the second signal.