Compensation for Capacitance Change in Touch Sensing Device
First Claim
1. A touch sensing device comprising:
- at least one capacitive sensor disposed on a first substrate for sensing a touch at the sensor;
a first conductive trace disposed on a second substrate and coupled to the sensor for transmitting a touch capacitance measurement indicative of the touch; and
a second conductive trace disposed on the second substrate, decoupled from the sensor, and proximate to the first conductive trace, the second conductive trace for transmitting a reference capacitance measurement indicative of a non-touch capacitance change so as to compensate for the non-touch capacitance change during transmission of the touch capacitance measurement, the non-touch capacitance change being associated with at least one of the first substrate or the second substrate.
1 Assignment
0 Petitions
Accused Products
Abstract
This relates to compensation for undesirable capacitance changes in a touch sensing device, where the capacitance changes are not indicative of a touch at the device. The touch sensing device can include a touch sensor panel having touch sensors for sensing a touch at the panel, a flexible circuit for transmitting the sensed touch signal from the panel, and a touch controller for receiving and processing the transmitted signal. To compensate for the capacitance changes, the touch sensing device can include one or more reference conductive traces decoupled from touch sensors of the device to measure non-touch capacitances in the device. The touch sensing device can then adjust a touch signal from the touch sensors using the non-touch capacitance measurements to substantially reduce or eliminate the non-touch capacitances from the signal.
47 Citations
25 Claims
-
1. A touch sensing device comprising:
-
at least one capacitive sensor disposed on a first substrate for sensing a touch at the sensor; a first conductive trace disposed on a second substrate and coupled to the sensor for transmitting a touch capacitance measurement indicative of the touch; and a second conductive trace disposed on the second substrate, decoupled from the sensor, and proximate to the first conductive trace, the second conductive trace for transmitting a reference capacitance measurement indicative of a non-touch capacitance change so as to compensate for the non-touch capacitance change during transmission of the touch capacitance measurement, the non-touch capacitance change being associated with at least one of the first substrate or the second substrate. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
-
-
9. A circuit comprising:
-
a first substrate having a sensor thereon, the first substrate being sensitive to a state change in the circuit; a second substrate having at least two conductive traces thereon, the second substrate being sensitive to the state change in the circuit, a first of the conductive traces being associated with the sensor to transmit a signal from the sensor and a second of the conductive traces being disassociated from the sensor; and logic for determining from the second of the conductive traces a capacitance effect of the state change at the second substrate and for reducing the determined capacitance effect in the transmitted signal. - View Dependent Claims (10, 11, 12, 13, 14, 15, 16, 17)
-
-
18. A method comprising:
-
measuring a touch at a touch sensing device, the touch measurement comprising a first capacitance of a touch region of the device, the first capacitance indicative of a touch at the device, and a second capacitance of a transmitting region of the device coupled to the touch region, the second capacitance indicative of an environmental change at the device; measuring the second capacitance in the transmitting region using a reference conductive trace decoupled from the touch region; and adjusting the touch measurement based on the second capacitance measurement to compensate the touch measurement for the environmental change at the device. - View Dependent Claims (19, 20, 21)
-
-
22. A touch sensing device comprising:
-
multiple touch sensors disposed on a substrate to sense a touch at the device; a flexible circuit coupled to the touch sensors to transmit touch signals from the touch sensors indicative of the sensed touch, the flexible circuit including a first conductive trace to transmit the touch signals and a second conductive trace to measure an effect of an environmental change on the device; and a sensing circuit coupled to the flexible circuit to process the transmitted touch signals, including compensating the transmitted touch signals for the measured effect of the environmental change, wherein at least one of the substrate, the flexible circuit, or the sensing circuit is sensitive to the environmental change. - View Dependent Claims (23, 24)
-
-
25. A method comprising:
-
measuring a first capacitance change associated with a touch at a touch sensing device using a first conductive trace coupled to a touch sensor of the device; measuring a second capacitance change at the touch sensing device using a second conductive trace positioned parallel to the first conductive trace and decoupled from the touch sensor, the second capacitance change not associated with the touch and associated with an operating change of the device; and adjusting the first capacitance measurement based on the second capacitance measurement to compensate for the second capacitance change.
-
Specification