LIQUID CRYSTAL DISPLAY DEVICE WITH TOUCH SENSOR, AND ELECTRONIC APPARATUS

• US 20150293639A1
• Filed: 06/24/2015
• Published: 10/15/2015
• Est. Priority Date: 07/24/2012
• Status: Active Grant

• Current Assignee: Japan Display Incorporated
• Original Assignee: Japan Display Incorporated
• Inventors: KURASAWA, Hayato, HAYASHI, Makoto, FURUTANI, Naosuke
• Granted Patent: US 9,477,341 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G02F 1/133302 Rigid substrates, e.g. inorganic substrates
• CPC Class Codes: G02F 1/133345 Insulating layers G02F1/1335, G02F1/1337, G02F1/135, G02F1/136 take precedence
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G02F 1/133514 Colour filters
• CPC Class Codes: G02F 1/133707 Structures for producing distorted electric fields, e.g. bumps, protrusions, recesses, slits in pixel electrodes
• CPC Class Codes: G02F 1/134309 characterised by their geometrical arrangement
• CPC Class Codes: G02F 1/134318 having a patterned common electrode
• CPC Class Codes: G02F 1/13439 characterised by their electrical, optical, physical properties; materials therefor; method of making
• CPC Class Codes: G02F 1/136213 Storage capacitors associated with the pixel electrode
• CPC Class Codes: G02F 1/136286 Wiring, e.g. gate line, drain line
• CPC Class Codes: G02F 1/1368 in which the switching element is a three-electrode device G02F1/136277 takes precedence
• CPC Class Codes: G02F 2201/121 common or background
• CPC Class Codes: G02F 2201/123 pixel
• CPC Class Codes: G06F 2203/04103 Manufacturing, i.e. details related to manufacturing processes specially suited for touch sensitive devices
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/0416 Control or interface arrangements specially adapted for digitisers
• 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 3/044 by capacitive means
• 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 2300/0426 : Layout of electrodes and connections
• CPC Class Codes: G09G 2330/02 : Details of power systems and of start or stop of display operation
• CPC Class Codes: G09G 3/3607 : for displaying colours or for displaying grey scales with a specific pixel layout, e.g. using sub-pixels display of colours in flat matrix panels other than liquid crystal displays G09G3/2003; grey scales specific for television H04N3/127
• CPC Class Codes: G09G 3/3648 : using an active matrix G09G3/367 - G09G3/3696 take precedence

Abstract

A liquid crystal display device with a touch sensor has a liquid crystal display function and a touch sensor function is providing and includes a first substrate including a pixel electrode and a first electrode; a second substrate including a second electrode; and a liquid crystal layer provided between the first substrate and the second substrate. When the liquid crystal display function is activated, the first and second electrodes are supplied with common voltage. When the touch sensor function is activated, the first electrode is applied with a first signal, and the second electrode is configured to receive the first signal to be a second signal as a touch detecting signal.

Claims

1. A liquid crystal display device with a touch sensor having a liquid crystal display function and a touch sensor function, the liquid crystal device comprising:

a first substrate including a pixel electrode and a first electrode;

a second substrate including a second electrode; and

a liquid crystal layer provided between the first substrate and the second substrate, wherein

upon the liquid crystal display function being activated, the pixel electrode is supplied with a pixel signal, and the first and second electrodes are supplied with common voltage, and

upon the touch sensor function being activated, the first electrode is applied with a first signal and the second electrode is configured to receive the first signal to be a second signal as a touch detecting signal;

the first electrode includes patterns of electrodes along a first direction, each of the patterns being configured to form a holding capacitor,

the second electrode includes patterns of electrodes along a second direction on the second substrate,

the patterns of the first electrode on the first substrate face the patterns of second electrode on the second substrate, and

the patterns of first electrode cross the patterns of second electrode in a planar view.

2. The liquid crystal display device with a touch sensor according to claim 1, wherein

the patterns of the second electrode includes

a first pattern configured to be used as a sensor pattern through which the second signal is detected upon the touch sensor function being activated and

a second pattern configured to be separated from the outside upon the touch sensor function being activated, and

the first pattern and the second pattern have therebetween a slit to generate a fringe electric field.

3. The liquid crystal display device with a touch sensor according to claim 2, wherein

the first substrate includes a source line that is connected to the pixel electrode, and

the first pattern is arranged to overlap the source line in a planar view.

4. The liquid crystal display device with a touch sensor according to claim 2, further comprising a selection circuit including a switch configured to switch a connection state between the second pattern and the selection circuit to ON or OFF, wherein

the second pattern is supplied with the common voltage when the connection state is turned ON.

5. The liquid crystal display device with a touch sensor according to claim 2, wherein

the first pattern has a portion overlapping the second pattern in a plane view, a width of the portion being smaller than that of the other portion.

6. The liquid crystal display device with a touch sensor according to claim 1, further comprising

a first electrode driver connected to the first electrode;

and

a second electrode driver connected to the second electrode, wherein

the first electrode driver is configured to

supply the common voltage to the first electrode in a pixel writing period of a horizontal period and

apply the first signal to the first electrode in a touch sensing period of the horizontal period, and

the second electrode driver is configured to

supply the common voltage to the second electrode in the pixel writing period of the horizontal period and

detect the second signal through the second electrode in the touch sensing period of the horizontal period.

7. The liquid crystal display device with a touch sensor according to claim 2, further comprising

a first electrode driver connected to the first electrode;

and

a second electrode driver including

a detection circuit connected to the first pattern of the second electrode; and

a selection circuit connected to the second pattern of the second electrode, wherein

the detection circuit is configured to calculate presence or absence of touching and/or a position of the touching based on the second signal from of the first pattern and output a resultant signal, and

the selection circuit includes a switch connected to the second pattern and is configured to

turn on the switch to supply the common voltage to the first electrode in a pixel writing period of a horizontal period and

turn off the switch in a touch sensing period of the horizontal period.

8. The liquid crystal display device with a touch sensor according to claim 6, further comprising:

a gate line on the first substrate;

a source line on the first substrate;

a color filter on the second substrate;

a gate driver connected to the gate line;

a source driver connected to the source line;

a first controller that is connected to the first electrode driver and the second electrode driver and that is configured to perform driving control of the touch sensor function; and

a second controller that is connected to the gate driver and the source driver and is configured to perform driving control of the liquid crystal display function.

9. An electronic apparatus including a liquid crystal display device with a touch sensor having a liquid crystal display function and a touch sensor function, the liquid crystal device comprising:

a first substrate including a pixel electrode and a first electrode;

a second substrate including a second electrode; and

a liquid crystal layer provided between the first substrate and the second substrate, wherein

upon the liquid crystal display function being activated, the pixel electrode is supplied with a pixel signal, and the first and second electrodes are supplied with common voltage, and

upon the touch sensor function being activated, the first electrode is applied with a first signal and the second electrode is configured to receive the first signal to be a second signal as a touch detecting signal;

the first electrode includes patterns of electrodes along a first direction, each of the patterns being configured to form a holding capacitor,

the second electrode includes patterns of electrodes along a second direction on the second substrate,

the patterns of the first electrode on the first substrate face the patterns of second electrode on the second substrate, and

the patterns of first electrode cross the patterns of second electrode in a planar view.