Capacitive touch detecting device and method using level shift, and display device using the same

• US 9,772,732 B2
• Filed: 07/28/2015
• Issued: 09/26/2017
• Est. Priority Date: 09/01/2010
• Status: Active Grant

• Current Assignee: G2touch Co Ltd
• Original Assignee: G2touch Co Ltd
• Inventors: Lee, Sung Ho
• Primary Examiner(s): Shankar, Vijay
• Assistant Examiner(s): Sarma, Abhishek
• Application Number:
  US14/811,111
• Publication Number:
  US 20150331521A1
• Time in Patent Office: 791 Days
• Field of Search: 345173-174
• CPC Class Codes: G06F 2203/04104 Multi-touch detection in digitiser, i.e. details about the simultaneous detection of a plurality of touching locations, e.g. multiple fingers or pen and finger
• CPC Class Codes: G06F 2203/04111 Cross over in capacitive digitiser, i.e. details of structures for connecting electrodes of the sensing pattern where the connections cross each other, e.g. bridge structures comprising an insulating layer, or vias through substrate
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/04166 Details of scanning methods, e.g. sampling time, grouping of sub areas or time sharing with display driving Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally G06F3/04184
• CPC Class Codes: G06F 3/0418 for error correction or compensation, e.g. based on parallax, calibration or alignment
• 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

Abstract

Provided is a touch detecting device that detects occurrence of a level shift phenomenon of a voltage variation to thus acquire a touch signal, when a touch capacitance due to a touch input is added to a common electrode capacitance formed between a common electrode and a sensor pattern. Accordingly, the touch signal may be stably obtained in spite of external noise, and an influence due to a parasitic capacitance may be minimized.

Claims

1. A capacitive touch screen panel, comprising:

a plurality of sensor patterns, each of the sensor patterns forming a touch capacitance between a touch input instrument and the sensor pattern;

a common electrode that forms a common electrode capacitance between the sensor pattern and the common electrode; and

a plurality of touch drive ICs that control the sensor patterns,

wherein the sensor pattern is directly disposed on an upper surface of a color filter of a display device,

wherein the common electrode is directly disposed on a lower surface of the color filter,

wherein the touch drive ICs are directly mounted on the upper surface of the color filter in a form of a chip on glass (COG), and the touch drive ICs include at least one master touch drive IC and at least one slave touch drive IC,

wherein the master touch drive IC and the slave touch drive IC scan the touch screen panel based on a pre-determined scanning priority or a scanning order, and

wherein the sensor patterns are grouped and connected with the master touch drive IC and the slave touch drive IC through a multiplexer, signals from sensor patterns within a group are multiplexed by the multiplexer, and the signal from each of the sensor patterns within the group is individually processed.

2. The capacitive touch screen panel of claim 1, wherein the common electrode applies a common voltage to the touch screen panel and the display device.

3. The capacitive touch screen panel of claim 1, wherein a touch drive IC applies a common voltage alternating at a predetermined frequency to the common electrode.

4. The capacitive touch screen panel of claim 1, wherein a display drive IC for controlling the display device applies a common voltage alternating at a predetermined frequency to the common electrode.

5. A display device including a capacitive touch screen panel, the display device comprising:

a plurality of sensor patterns, each of the sensor patterns forming a touch capacitance between a touch input instrument and the sensor pattern;

a common electrode that forms a common electrode capacitance between the sensor pattern and the common electrode;

a color filter that is disposed between the sensor pattern and the common electrode; and

a plurality of touch drive ICs that control the sensor patterns,

wherein the sensor pattern is directly disposed on an upper surface of the color filter,

wherein the common electrode is directly disposed on a lower surface of the color filter,

wherein the touch drive ICs are directly mounted on the upper surface of the color filter in a form of a chip on glass (COG), and the touch drive ICs include at least one master touch drive IC and at least one slave touch drive IC,

wherein the master touch drive IC and the slave touch drive IC scan the touch screen panel based on a pre-determined scanning priority or a scanning order, and

wherein the sensor patterns are grouped and connected with the master touch drive IC and the slave touch drive IC through a multiplexer, signals from the sensor patterns within a group are multiplexed by the multiplexer, and the signal from each of the sensor patterns within the group is individually processed.

6. The display device of claim 5, further comprising:

a display layer on which a thin film transistor (TFT) substrate and a liquid crystal layer are stacked.

7. The display device of claim 5, wherein the common electrode applies a common voltage to the display device.

8. The display device of claim 5, wherein a touch drive IC applies an alternating common voltage to the common electrode.