Display device

• US 10,185,434 B2
• Filed: 10/27/2016
• Issued: 01/22/2019
• Est. Priority Date: 03/11/2013
• Status: Active Grant

• Current Assignee: Japan Display Incorporated
• Original Assignee: Japan Display Incorporated
• Inventors: Suzuki, Takafumi, Azumi, Kohei
• Primary Examiner(s): Lam, Vinh T
• Application Number:
  US15/336,290
• Publication Number:
  US 20170045997A1
• Time in Patent Office: 817 Days
• Field of Search: 345 87- 94, 345173-174, 345 38, 345 50- 53, 345 64, 345104, 349139, 349142, 349143, 349148, 349151
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• 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 2203/04108 Touchless 2D- digitiser, i.e. digitiser detecting the X/Y position of the input means, finger or stylus, also when it does not touch, but is proximate to the digitiser's interaction surface without distance measurement in the Z direction
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/04164 Connections between sensors and controllers, e.g. routing lines between electrodes and connection pads
• 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 3/0445 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

A display device is provided. The display device including a display panel including a display area, a frame area; a plurality of pixel electrodes in the display area; a plurality of share electrodes in the display area; a display function layer controlled by the pixel electrodes and the share electrodes; a plurality of touch detect electrodes forming capacitors with the plurality of the share electrodes; a circuit for generating signals to apply to the share electrodes; and a plurality of wirings coupled to the circuit and the share electrodes in the frame area, wherein the longer a path including each of the share electrodes and each of the wirings is, the shorter pulses of each of the signals become.

Claims

1. A display device comprising:

a display panel including a display area, a frame area;

pixel electrodes including first pixel electrodes and second pixel electrodes in the display area;

share electrodes including first share electrodes opposed to the first pixel electrodes and second share electrodes opposed to the second pixel electrodes;

a display function layer controlled by the pixel electrodes and the share electrodes;

a driving circuit electrically connected to the first and second share electrodes, and configured to drive the first and second share electrodes; and

a first group of wirings coupled between the driving circuit and the first share electrodes in the frame area,

a second group of wirings coupled between the driving circuit and the second share electrodes,

wherein each of the first group of wiring is longer than each of the second group of wirings,

wherein the first and second share electrodes are driven with a display drive signal during a display period, and the first share electrodes are driven with a first touch detection drive pulse simultaneously during a first touch detection period, and the second share electrodes are driven with a second touch detection drive pulse simultaneously during a second touch detection period, and

wherein a width of the first touch detection drive pulse is longer than the second touch detection drive pulse.

2. The display device according to claim 1, wherein

the display function layer is a liquid crystal layer.

3. The display device according to claim 1, wherein,

in a touch detection area, capacitors are formed by each of the share electrodes.

4. The display device according to claim 1, wherein,

the first group of wirings are disposed in a first region of the frame area and the second group of wirings are disposed in a second region of the frame area which is closer than the first region from the driving circuit;

the first group of wirings is respectively coupled to both ends of the corresponding first share electrodes among the share electrodes;

the second group of wirings is respectively coupled to both ends of the corresponding second share electrodes; and

the first and second touch detection drive pulses are sequentially applied to the first and second share electrodes from the driving circuit.

5. The display device according to claim 1, wherein,

the first and second groups of wirings are disposed in the frame area;

the first and second groups of wirings are respectively coupled to first ends of the corresponding share electrodes; and

,

the first and second touch detection drive pulses are sequentially applied to the first and second share electrodes of a touch detection area through the plurality of wirings.

6. The display device according to claim 1, wherein,

the first group of wirings are disposed in a first region of the frame area and the second group of wirings are disposed in a second region of the frame area;

the first group of wirings is respectively coupled to first ends of the first share electrodes;

the second group of wirings is respectively coupled to second ends of the second share electrodes; and

,

the first and second touch detection drive pulses are sequentially applied to the first and second share electrodes of a touch detection area through the wirings.

7. The display device according to claim 1, further comprising a touch detect circuit configured to detect an external object in response to the first and second touch detection drive pulses applied to the share electrodes.

8. The display device according to claim 1, further comprising a pulse changing circuit configured to change a pulse cycle of one or both of the first and second touch detection drive pulses applied to at least one of the share electrodes from the driving circuit.

9. The display device according to claim 1, further comprising a pulse changing circuit configured to change a number of one or both of the first and second touch detection drive pulses applied to at least one of the share electrodes from the driving circuit.

10. The display device according to claim 8, further comprising:

a noise detecting circuit configured to detect noise,

the pulse changing circuit configured to change the pulse cycle based on the noise detected by the noise detecting circuit.