TOUCH SENSING APPARATUS

• US 20140184557A1
• Filed: 03/13/2013
• Published: 07/03/2014
• Est. Priority Date: 12/28/2012
• Status: Active Grant

• Current Assignee: Samsung Electro-Mechanics Co., Ltd. (Samsung Group)
• Original Assignee: Samsung Electro-Mechanics Co., Ltd. (Samsung Group)
• Inventors: JEONG, Moon Suk, JO, Byeong Hak, KWON, Yong II, PARK, Tah Joon
• Granted Patent: US 9,098,157 B2
• Time in Patent Office: Days
• US Class Current: 345/174
• CPC Class Codes: G06F 3/0418 for error correction or compensation, e.g. based on parallax, calibration or alignment
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes
• CPC Class Codes: G06F 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer
• CPC Class Codes: G06F 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes

Abstract

There is provided a touch sensing apparatus including: a panel unit including a plurality of driving electrodes and a plurality of sensing electrodes; a driving circuit unit applying one of a driving signal and a scanning signal having a frequency different from that of the driving signal, to each of the plurality of driving electrodes; a sensing circuit unit measuring a change in capacitance of a plurality of node capacitors generated in intersections of the plurality of driving electrodes and the plurality of sensing electrodes; and a calculation unit determining a touch based on a change in the capacitance, wherein when the scanning signal is applied to the plurality of driving electrodes, the calculation unit calculates capacitance deviations in the plurality of node capacitors from the deviations of changes in the capacitance generated by the plurality of node capacitors.

Claims

1. A touch sensing apparatus comprising:

a panel unit including a plurality of driving electrodes and a plurality of sensing electrodes;

a driving circuit unit applying one of a driving signal and a scanning signal having a frequency different from that of the driving signal, to each of the plurality of driving electrodes;

a sensing circuit unit measuring a change in capacitance of a plurality of node capacitors generated in intersections of the plurality of driving electrodes and the plurality of sensing electrodes; and

a calculation unit determining a touch based on a change in the capacitance,

wherein when the scanning signal is applied to the plurality of driving electrodes, the calculation unit calculates capacitance deviations in the plurality of node capacitors from the deviations of changes in the capacitance generated by the plurality of node capacitors.

2. The touch sensing apparatus of claim 1, wherein the scanning signal has a frequency lower than that of the driving signal.

3. The touch sensing apparatus of claim 2, wherein the scanning signal is applied in a state in which the panel unit is not touched.

4. The touch sensing apparatus of claim 1, wherein when the driving signal is applied to the plurality of driving electrodes, the calculation unit generates compensation data for compensating for capacitance deviations in the plurality of node capacitors such that changes in capacitance generated by the plurality of node capacitors are uniform.

5. The touch sensing apparatus of claim 4, wherein the calculation unit controls a gain of the sensing circuit unit according to the compensation data.

6. The touch sensing apparatus of claim 1, wherein the sensing circuit unit comprises at least one capacitor for measuring a change in capacitance, and the calculation unit adjusts capacitance of the at least one capacitor according to the compensation data.

7. The touch sensing apparatus of claim 1, wherein the calculation unit determines at least one of the amount of touch inputs, coordinates of touch inputs, and a touch gesture based on the change in the capacitance.

8. A touch sensing apparatus comprising:

a panel unit including a plurality of first electrodes extending in a first axial direction and a plurality of second electrodes extending in a second axial direction crossing the first axial direction; and

a controller determining a touch by detecting a change in capacitance of a plurality of node capacitors formed between the plurality of first electrodes and the plurality of second electrodes;

wherein when a scanning signal having a predetermined frequency is applied to the plurality of first electrodes, the controller calculates capacitance deviations in the plurality of node capacitors from deviations of the changes in capacitance of the plurality of node capacitors.

9. The touch sensing apparatus of claim 8, wherein the scanning signal is applied in a state in which the panel unit is not touched.

10. The touch sensing apparatus of claim 8, wherein when a driving signal having a frequency higher than that of the scanning signal is applied to the first electrodes, the controller generates compensation data for compensating for capacitance deviations in the plurality of capacitors such that changes in capacitance generated by the plurality of node capacitors are uniform.

11. The touch sensing apparatus of claim 10, wherein the controller adjusts capacitance of at least one capacitor provided to detect a change in capacitance according to the compensation data.

12. The touch sensing apparatus of claim 8, wherein the calculation unit determines at least one of the amount of touch inputs, coordinates of touch inputs, and a touch gesture by detecting a change in capacitance.