Localizing an electrostatic stylus within a capacitive touch sensor
First Claim
1. An active stylus configured to operate with a capacitive touch sensor, the active stylus comprising:
- an electrode configured to both receive and transmit signals, and configured to electrostatically couple with the capacitive touch sensor;
a switch, coupled with the electrode, that is configured to multiplex a relatively large voltage and a relatively small current, wherein the switch is configured to transmit a voltage to the electrode in a transmission mode, and to receive a current from the electrode in a receiving mode;
a conductive tip for receiving current from the electrode through the switch, and for transmitting voltage that is coupled through the switch to the electrode;
a microcontroller configured to determine at least one position of the active stylus with respect to locations on the capacitive touch sensor based on a first signal received from the capacitive touch sensor in a first timeslot, and to report the at least one position of the active stylus in a second timeslot allocated for reporting the at least one position to the capacitive touch sensor that differs from the first timeslot; and
an internal power source to provide power to at least the microcontroller.
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0 Petitions
Accused Products
Abstract
Methods, systems, and apparatus relate to capacitive touch sensors with a fine-pointed, active stylus. The active stylus is configured to receive a signal from the capacitive touch sensor for synchronizing a time base of the stylus with the capacitive touch sensor. The active stylus is configured to receive a signal from a matrix of the capacitive touch sensor to measure a first position along one axis, and transmit a signal from the single electrode of the stylus to the matrix to indicate a second position of the stylus along another axis of the matrix. The stylus can transmit the received signal to report the first position of the stylus.
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Citations
20 Claims
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1. An active stylus configured to operate with a capacitive touch sensor, the active stylus comprising:
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an electrode configured to both receive and transmit signals, and configured to electrostatically couple with the capacitive touch sensor; a switch, coupled with the electrode, that is configured to multiplex a relatively large voltage and a relatively small current, wherein the switch is configured to transmit a voltage to the electrode in a transmission mode, and to receive a current from the electrode in a receiving mode; a conductive tip for receiving current from the electrode through the switch, and for transmitting voltage that is coupled through the switch to the electrode; a microcontroller configured to determine at least one position of the active stylus with respect to locations on the capacitive touch sensor based on a first signal received from the capacitive touch sensor in a first timeslot, and to report the at least one position of the active stylus in a second timeslot allocated for reporting the at least one position to the capacitive touch sensor that differs from the first timeslot; and an internal power source to provide power to at least the microcontroller. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13)
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14. An active stylus configured to operate with a capacitive touch sensor, the active stylus comprising:
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an electrode configured to both receive and transmit signals, and configured to electrostatically couple with the capacitive touch sensor; a switch, coupled with the electrode, that is configured to multiplex a relatively large voltage and a relatively small current, wherein the switch is configured to transmit a voltage to the electrode in a transmission mode, and to receive a current from the electrode in a receiving mode; a receiver circuit for receiving current from the electrode through the switch; a transmitter circuit for transmitting voltage that is coupled through the switch to the electrode; a microcontroller configured to determine at least one position of the active stylus with respect to locations on the capacitive touch sensor based on a first signal received from the capacitive touch sensor in a first timeslot, and to report the at least one position of the active stylus in a second timeslot allocated for reporting the at least one position to the capacitive touch sensor that differs from the first timeslot; and an internal power source to provide power to at least the microcontroller. - View Dependent Claims (15, 16, 17, 18, 19)
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20. An active stylus configured to operate with a capacitive touch sensor, the active stylus comprising:
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an electrode configured to both receive and transmit signals, and configured to electrostatically couple with the capacitive touch sensor; a circuit comprising; a switch, coupled with the electrode, that is configured to multiplex a relatively large voltage and a relatively small current, wherein the switch is configured to transmit a voltage to the electrode in a transmission mode, and to receive a current from the electrode in a receiving mode; a receiver circuit for receiving current from the electrode through the switch; and a transmitter circuit for transmitting voltage that is coupled through the switch to the electrode; a microcontroller coupled to the receiver circuit and to the transmitter circuit and configured to determine at least one position of the active stylus with respect to locations on the capacitive touch sensor based on a first signal received from the capacitive touch sensor in a first timeslot, and to report the at least one position of the active stylus in a second timeslot allocated for reporting the at least one position to the capacitive touch sensor that differs from the first timeslot; and an internal power source to provide power to at least the microcontroller.
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Specification