Stylus detection and demodulation
First Claim
Patent Images
1. A method of detecting stylus signals generated by an asynchronous stylus on a touch input device, the method comprising:
- configuring the touch input device to receive a stylus signal, the stylus signal generated by the asynchronous stylus, wherein the asynchronous stylus generates the stylus signal asynchronously from the touch input device, and the stylus signal generated by the asynchronous stylus has a start time and an end time;
receiving the stylus signal at a plurality of stylus signal detectors, each of the plurality of stylus signal detectors corresponding to one of a plurality of sense channels of the touch input device;
generating one or more metrics at the plurality of stylus signal detectors pertaining to the received stylus signal, the metrics comprising a first time corresponding to an estimated start time of the received stylus signal and a second time corresponding to an estimated end time of the stylus signal transmission;
determining which of the plurality of stylus signal detectors has a greatest likelihood of having received the stylus signal based on the one or more metrics; and
demodulating the received stylus signal, at a plurality of demodulators, each of the plurality of demodulators corresponding to one of the plurality of sense channels of the input device, based on the first time and the second time from the stylus signal detector determined to have the greatest likelihood of having received the stylus signal.
1 Assignment
0 Petitions
Accused Products
Abstract
A touch input device configured to detect stylus signals generated by an external stylus is provided. The touch input device includes a plurality of stylus signal detectors that can receive the stylus signal and estimate the start and end time of the stylus signal in order to facilitate windowed demodulation of signal. The touch input device also includes circuitry to determine which of the plurality of detectors is most likely to have received the stylus signal and based on that determination can demodulate the signal and extract data embedded within the stylus signal.
-
Citations
24 Claims
-
1. A method of detecting stylus signals generated by an asynchronous stylus on a touch input device, the method comprising:
-
configuring the touch input device to receive a stylus signal, the stylus signal generated by the asynchronous stylus, wherein the asynchronous stylus generates the stylus signal asynchronously from the touch input device, and the stylus signal generated by the asynchronous stylus has a start time and an end time; receiving the stylus signal at a plurality of stylus signal detectors, each of the plurality of stylus signal detectors corresponding to one of a plurality of sense channels of the touch input device; generating one or more metrics at the plurality of stylus signal detectors pertaining to the received stylus signal, the metrics comprising a first time corresponding to an estimated start time of the received stylus signal and a second time corresponding to an estimated end time of the stylus signal transmission; determining which of the plurality of stylus signal detectors has a greatest likelihood of having received the stylus signal based on the one or more metrics; and demodulating the received stylus signal, at a plurality of demodulators, each of the plurality of demodulators corresponding to one of the plurality of sense channels of the input device, based on the first time and the second time from the stylus signal detector determined to have the greatest likelihood of having received the stylus signal. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
-
-
9. An apparatus for detecting stylus signals generated by an asynchronous stylus on a touch input device, the apparatus comprising:
-
a plurality of electrodes capable of operating as touch detection hardware during a touch operation mode and operating as stylus detection hardware during a stylus detection mode; a plurality of stylus signal detectors coupled to the plurality of electrodes during a stylus detection mode, each of the plurality of stylus signal detectors corresponding to one of a plurality of sense channels of the touch input device, each of the plurality of stylus signal detectors capable of receiving a stylus signal, the stylus signal generated by the asynchronous stylus, wherein the asynchronous stylus generates the stylus signal asynchronously from the touch input device, and the stylus signal generated by the asynchronous stylus has a start time and an end time, and generating one or more metrics pertaining to the received stylus signal, the metrics comprising a first time corresponding to an estimated start time of the received stylus signal and a second time corresponding to an estimated end time of stylus signal transmission; an arbiter coupled to the plurality of stylus signal detectors and capable of; determining which of the plurality of stylus signal detectors has the greatest likelihood of having received the stylus signal based on the metrics transmitted by the stylus signal detectors; and outputting the first time and the second time from the stylus signal detector determined to have the greatest likelihood of having received the stylus signal; and a plurality of demodulators, each of the plurality of demodulators corresponding to one of the plurality of sense channels of the input device and configured to demodulate the received stylus signal based on the first time and the second time from the stylus signal detector determined to have the greatest likelihood of having received the stylus signal. - View Dependent Claims (10, 11, 12, 13, 14, 15, 16)
-
-
17. A non-transitory computer readable storage medium having stored thereon a set of instructions for detecting and demodulating a stylus signal generated by an asynchronous stylus, that when executed by a processor causes the processor to:
-
configure the touch input device to receive a stylus signal, the stylus signal generated by the asynchronous stylus, wherein the asynchronous stylus generates the stylus signal asynchronously from the touch input device, and the stylus signal generated by the asynchronous stylus has a start time and an end time; receive the stylus signal on a touch sensor panel at a plurality of stylus signal detectors, each of the plurality of stylus signal detectors corresponding to one of a plurality of sense channels of the touch input device; generate one or more metrics pertaining to the received stylus signal using the plurality of stylus signal detectors, the metrics comprising a first time corresponding to an estimated start time of the received stylus signal and a second time corresponding to an estimated end time of the stylus signal transmission; determine which of a plurality of stylus signal detectors has the greatest likelihood of having received the stylus signal based on the one or more metrics; and demodulate, at a plurality of demodulators, each of the plurality of demodulators corresponding to one of the plurality of sense channels of the input device, the received stylus signal based on the first time and the second time from the stylus signal detector determined to have the greatest likelihood of having received the stylus signal. - View Dependent Claims (18, 19, 20, 21, 22, 23, 24)
-
Specification