Display device with touch sensor

• US 9,335,875 B2
• Filed: 01/30/2014
• Issued: 05/10/2016
• Est. Priority Date: 03/28/2008
• Status: Active Grant

• Current Assignee: Japan Display Incorporated
• Original Assignee: Japan Display Incorporated
• Inventors: Noguchi, Koji, Takama, Daisuke, Kida, Yoshitoshi
• Primary Examiner(s): Moon, Seokyun
• Assistant Examiner(s): SOTO LOPEZ, JOSE R
• Application Number:
  US14/168,871
• Publication Number:
  US 20140146013A1
• Time in Patent Office: 831 Days
• Field of Search: 345/87, 345/173, 345/204
• US Class Current: 1/1
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G02F 1/134363 for applying an electric field parallel to the substrate, i.e. in-plane switching [IPS]
• CPC Class Codes: G02F 1/134372 for fringe field switching [FFS] where the common electrode is not patterned
• CPC Class Codes: G02F 2201/12 electrode
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/044 by capacitive means
• 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
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence

Abstract

A common electrode for a display used both in driving the display and touch detection. An existing common drive signal both as a drive signal for the touch sensor. A capacitance is formed between the common electrode and a touch sensor electrode. Touch detection is performed by utilizing a change of this capacitance caused by a finger touch of a user. The display device with a touch sensor can be used in a mobile device.

Claims

1. A display device having a capacitive touch sensor, comprising:

a first substrate;

a second substrate facing the first substrate;

a display function layer having an image display function, the display function layer being interposed between the first substrate and the second substrate;

a plurality of display pixel electrodes;

a common electrode facing the display pixel electrodes, the display pixel electrodes and the common electrode being disposed between the first substrate and the display function layer;

a control circuit that performs an image display control by applying a voltage for display between the display pixel electrode and the common electrode, based on an image signal, so that the display function of the display function layer is exhibited;

a touch detection electrode of the capacitive touch sensor, the touch detection electrode and the common electrode being arranged such that a capacitance is formed between the common electrode and the touch detection electrode; and

a touch detection circuit that detects a position touched by an object based on a detection signal obtained from the touch detection electrode,

wherein,

the touch detection electrode is between the second substrate and the display function layer, and

the second substrate is interposed between a first polarizing plate and the first substrate.

8. The display device of claim 1, wherein a dielectric is arranged directly between the touch detection electrode and the display function layer.

9. The display device of claim 8, wherein the dielectric comprises a color filter.

10. The display device of claim 1, wherein a drive voltage that is applied to the common electrode by the control circuit is also utilized as a drive signal for the capacitive touch sensor.

11. The display device of claim 10, wherein:

the common electrode is divided into a plurality of patterns, and

the drive signal for the capacitive touch sensor is sequentially applied in a time-division manner to each of the plurality of patterns of the common electrode.

12. The display device of claim 1, wherein both of the touch detection electrode and the common electrode are divided into a respective plurality of patterns.

13. The display device of claim 1, wherein the touch detection circuit detects a touch based on the capacitance formed between the common electrode and the touch detection electrode.

2. A display device having a capacitive touch sensor, comprising:

a first substrate;

a second substrate facing the first substrate;

a display function layer having an image display function, the display function layer being interposed between the first substrate and the second substrate;

a plurality of display pixel electrodes;

a common electrode facing the display pixel electrodes, the display pixel electrodes and the common electrode being disposed between the first substrate and the display function layer;

a control circuit that performs an image display control by applying a voltage for display between the display pixel electrode and the common electrode, based on an image signal, so that the display function of the display function layer is exhibited;

a touch detection electrode disposed opposite to the common electrode, the touch detection electrode and the common electrode being arranged such that a capacitance is formed between the common electrode and the touch detection electrode; and

a touch detection circuit that detects a position touched by an object based on a detection signal obtained from the touch detection electrode,

wherein,

the touch detection electrode is between the second substrate and the display function layer, and

the second substrate is interposed between a first polarizing plate and the first substrate, and

the touch detection electrode comprises a plurality of individual electrodes, the plurality of individual electrodes being formed in one layer on a same plane.

3. The display device of claim 2, wherein the common electrode is divided into a plurality of stripe-shaped patterns, the plurality of stripe-shaped patterns of the common electrode and the plurality of individual electrodes of the touch detection electrode being arranged so as to intersect each other.

4. The display device of claim 2, wherein the plurality of individual electrodes of the touch detection electrode are arranged in a matrix form.

14. The display device of claim 2, wherein a drive voltage that is applied to the common electrode by the control circuit is also utilized as a drive signal for the capacitive touch sensor.

5. A display device having a capacitive touch sensor, comprising:

a first substrate;

second substrate facing the first substrate;

a display function layer having an image display function, the display function layer being interposed between the first substrate and the second substrate;

a plurality of display pixel electrodes;

a common electrode facing the display pixel electrodes, the display pixel electrodes and the common electrode being disposed between the first substrate and the display function layer;

a control circuit that controls display of an image by applying a voltage between the display pixel electrode and the common electrode based on an image signal, so that the display function of the display function layer is exhibited;

a touch detection electrode, the touch detection electrode overlapping the common electrode, the touch detection electrode and the common electrode being arranged such that a capacitance is formed between the common electrode and the touch detection electrode; and

a touch detection circuit that detects a position touched by an object based on a detection signal obtained from the touch detection electrode,

wherein,

the touch detection electrode is between the second substrate and the display function layer, and the second substrate is interposed between a first polarizing plate and the first substrate, and

the common electrode is divided into a plurality of elongated electrode members.

6. The display device of claim 5, wherein:

the touch detection electrode comprises a plurality of individual electrodes, and

the individual electrodes are stripe-shaped members.

7. The display device of claim 5, wherein:

the touch detection electrode comprises a plurality of individual electrodes, and

each of the individual electrodes is rectilinear in shape.

15. The display device of claim 5, wherein a drive voltage that is applied to the common electrode by the control circuit is also utilized as a drive signal for the capacitive touch sensor.