TOUCH SENSING DEVICE AND TOUCHSCREEN DEVICE

• US 20140253491A1
• Filed: 05/14/2013
• Published: 09/11/2014
• Est. Priority Date: 03/07/2013
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electro-Mechanics Co., Ltd. (Samsung Group)
• Inventors: KWON, Yong Il, PARK, Tah Joon, JO, Byeong Hak, LEE, Hyun Suk
• Granted Patent: US 9,389,735 B2
• Time in Patent Office: Days
• US Class Current: 345/174
• CPC Class Codes: G06F 2203/04107 Shielding in digitiser, i.e. guard or shielding arrangements, mostly for capacitive touchscreens, e.g. driven shields, driven grounds
• 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 are provided a touch sensing device and a touchscreen device, the touch sensing device including a plurality of driving electrodes extended in a first axial direction, a plurality of sensing electrodes extended in a second axial direction intersecting with the first axial direction, an integrating circuit unit generating a first analog signal by integrating a change in capacitance generated in a first sensing electrode among the plurality of sensing electrodes and generating a second analog signal from a change in capacitance generated in a second sensing electrode adjacent to the first sensing electrode, and a subtracting unit calculating a difference in levels between the first and second analog signals.

Claims

1. A touch sensing device comprising:

a plurality of driving electrodes extended in a first axial direction;

a plurality of sensing electrodes extended in a second axial direction intersecting with the first axial direction;

an integrating circuit unit generating a first analog signal by integrating a change in capacitance generated in a first sensing electrode among the plurality of sensing electrodes and generating a second analog signal from a change in capacitance generated in a second sensing electrode adjacent to the first sensing electrode; and

a subtracting unit calculating a difference in levels between the first and second analog signals.

2. The touch sensing device of claim 1, wherein the integrating circuit unit integrates the change in capacitance generated in the first sensing electrode and the change in capacitance generated in the second sensing electrode to have opposite polarities.

3. The touch sensing device of claim 1, wherein the subtracting unit calculates the difference in levels between the first and second analog signals to output a voltage having a positive polarity.

4. The touch sensing device of claim 1, wherein in the first and second analog signals, polarities of voltages are changed after a reset section of the integrating circuit unit.

5. The touch sensing device of claim 1, further comprising a driving circuit unit applying a predetermined driving signal to each of the plurality of driving electrodes.

6. A touchscreen device comprising:

a panel unit including a plurality of driving electrodes, a plurality of sensing electrodes, and a plurality of node capacitors formed in intersections between the plurality of driving electrodes and the plurality of sensing electrodes;

a driving circuit unit applying a driving signal having a predetermined driving period to each of the plurality of driving electrodes;

a sensing circuit unit connected to the plurality of sensing electrodes to detect changes in capacitance in the plurality of node capacitors; and

a signal processing unit converting an output of the sensing circuit unit into a digital signal to determine a touch input,

wherein the sensing circuit unit calculates a difference between changes in capacitance in node capacitors formed in the sensing electrodes adjacent to each other among the plurality of node capacitors.

7. The touchscreen device of claim 6, wherein the sensing circuit unit charges a plurality of the node capacitors formed in one sensing electrode of the sensing electrodes adjacent to each other and a plurality of the node capacitors formed in the other sensing electrode thereof with voltages having opposite polarities.

8. The touchscreen device of claim 6, wherein the sensing circuit unit includes:

a plurality of integrating circuits connected to the plurality of sensing electrodes, respectively;

a voltage setting unit setting polarities of voltages charged in the node capacitors formed in the sensing electrodes adjacent to each other to be opposed to each other; and

a subscribing unit calculating a difference in levels between output voltages of the integrating circuits connected to the sensing electrodes adjacent to each other, respectively.

9. The touchscreen device of claim 6, wherein the signal processing unit includes:

a signal converting unit converting the output of the sensing circuit unit into a digital signal; and

a calculating unit determining the touch input from the digital signal.

10. The touchscreen device of claim 9, wherein the calculating unit determines at least one of a gesture motion due to the touch input and the number of touch inputs.

11. The touchscreen device of claim 8, wherein the driving circuit unit applies predetermined first and second voltages at different times, and

the voltage setting unit selects one of the first voltage and a predetermined third voltage to set the polarities of the voltages charged in the node capacitors formed in the sensing electrodes adjacent to each other to be opposed to each other.

12. The touchscreen device of claim 11, wherein the first voltage, the second voltage, and the third voltages satisfy the following conditional Equation:

V1−

V2=Δ

V and V3−

V2=Δ

V  

 

[Conditional Equation]

where V1 indicates the first voltage, V2 indicates the second voltage, and V3 indicates the third voltage.