Display device with touch detection function, drive circuit, driving method of display device with touch detection function, and electronic unit

• US 8,933,895 B2
• Filed: 07/08/2011
• Issued: 01/13/2015
• Est. Priority Date: 08/23/2010
• Status: Active Grant

• Current Assignee: Japan Display Incorporated
• Original Assignee: Japan Display West Incorporated (Japan Display Incorporated)
• Inventors: Nakanishi, Takayuki, Kida, Yoshitoshi, Noguchi, Koji, Mizuhashi, Hiroshi, Ishizaki, Koji
• Primary Examiner(s): Wang, Quan-Zhen
• Assistant Examiner(s): DICKE, CHAD M
• Application Number:
  US13/067,934
• Publication Number:
  US 20120044195A1
• Time in Patent Office: 1,285 Days
• Field of Search: 345173-178, 178 1801- 2004, 349/12
• US Class Current: 345/173
• CPC Class Codes: G06F 2203/04101 2.5D-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 and also measures the distance of the input means within a short range in the Z direction, possibly with a separate measurement setup
• 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 3/0445 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: G06F 3/045 using resistive elements, e.g. a single continuous surface or two parallel surfaces put in contact
• CPC Class Codes: G09G 2354/00 Aspects of interface with display user
• CPC Class Codes: G09G 3/3655 Details of drivers for counter electrodes, e.g. common electrodes for pixel capacitors or supplementary storage capacitors
• CPC Class Codes: G09G 3/3677 suitable for active matrices only

Abstract

A display device with a touch detection function includes a plurality of common drive electrodes arranged side by side to extend in one direction, a display element performing display, based on a pixel signal and a display drive signal, a touch detection element of electrostatic capacitance type detecting an external proximity object based on a touch detection drive signal with an amplitude larger than that of the display drive signal, and a scan drive section performing first scan drive and second scan drive, the first scan drive allowing the plurality of common drive electrodes to be sequentially supplied with the display drive signal in a time-divisional manner, and the second scan drive allowing the plurality of common drive electrodes to be sequentially supplied with the touch detection drive signal in a time-divisional manner.

Claims

1. A display device with a touch detection function comprising:

a plurality of common drive electrodes arranged side by side to extend in one direction;

a display element performing display, based on a pixel signal and a display drive signal;

a touch detection element of electrostatic capacitance type detecting an external proximity object based on a touch detection drive signal with an amplitude larger than that of the display drive signal; and

a scan drive section performing first scan drive and second scan drive, the first scan drive allowing the plurality of common drive electrodes to be sequentially supplied with the display drive signal in a time-divisional manner, and the second scan drive allowing the plurality of common drive electrodes to be sequentially supplied with the touch detection drive signal in a time-divisional manner,

wherein the scan drive section includes;

a drive signal control circuit to which a first select signal for selecting one of the common drive electrodes as a target of the first scan drive and a second select signal for selecting one of the common drive electrodes as a target of the second scan drive are supplied,

a first switch allowing the target of the first scan drive to be supplied with the display drive signal,

a second switch allowing the target of the second scan drive to be supplied with the touch detection drive signal, and

a third switch allowing one of the common drive electrodes to be supplied with a direct-current potential,

wherein the drive signal control circuit is configured to;

when the first select signal is at a high level and the second select signal is not at the high level, turn on the first switch and turn off the second switch and the third switch to allow the target of the first scan drive to be supplied with the display drive signal,

when the first select signal is not at the high level and the second select signal is at the high level, turn off the first switch and the third switch and turn on the second switch to allow the target of the second scan drive to be supplied with the touch detection drive signal,

when the first select signal is at the high level and the second select signal is at the high level, turn on the first switch and turn off the second switch and the third switch to allow the target of the first scan drive to be supplied with the display drive signal, and

when the first select signal is not at high level and the second select signal is not at high level, turn off the first switch and the second switch and turn on the third switch to allow one of the common drive electrodes to be supplied with the direct-current potential.

2. The display device according to claim 1, wherein turning-on of the third switch allows unselected common drive electrodes, which are not selected as a target of the first and second scan drive, to be supplied with the direct-current potential.

3. The display device according to claim 2, wherein the direct-current potential is equal to a time-averaged voltage value of the display drive signal.

4. The display device according to claim 1, wherein the touch detection drive signal is a rectangular wave signal with alternately-inverted polarity.

5. A display device comprising:

a plurality of common drive electrodes;

a display element performing display based on a pixel signal and a display drive signal;

a detection element performing detection based on a detection drive signal with an amplitude larger than that of the display drive signal; and

a scan drive section including a drive signal control circuit to which a first select signal for selecting one of the common drive electrodes and a second select signal for selecting one of the common drive electrodes are supplied, and a first switch, a second switch, and a third switch, turning-on of the first switch allowing one of the common drive electrodes to be supplied with the display drive signal, turning-on of the second switch allowing said one of the common drive electrodes to be supplied with the detection drive signal, and turning-on the third switch allowing one of the common electrodes to be supplied with a direct-current potential,

wherein the drive signal control circuit is configured to;

when the first select signal is at a high level and the second select signal is not at the high level, turn on the first switch and turn off the second switch and the third switch to allow the target of the first scan drive to be supplied with the display drive signal,

when the first select signal is not at the high level and the second select signal is at the high level, turn off the first switch and the third switch and turn on the second switch to allow the target of the second scan drive to be supplied with the touch detection drive signal,

when the first select signal is at the high level and the second select signal is at the high level, turn on the first switch and turn off the second switch and the third switch to allow the target of the first scan drive to be supplied with the display drive signal, and

when the first select signal is not at high level and the second select signal is not at high level, turn off the first switch and the second switch and turn on the third switch to allow one of the common drive electrodes to be supplied with the direct-current potential.

6. A drive circuit comprising:

a scan drive section performing first scan drive and second scan drive,

the first scan drive allowing a plurality of common drive electrodes to be sequentially supplied with a display drive signal in a time-divisional manner, and

the second scan drive allowing the plurality of common drive electrodes to be sequentially supplied with a touch detection drive signal with an amplitude larger than that of the display drive signal in a time-divisional manner, on a display section with a touch detection function including the plurality of common drive electrodes, a display element, and a touch detection element of electrostatic capacitance type, the plurality of common drive electrodes being arranged side by side to extend in one direction,

the display element performing display based on a pixel signal and the display drive signal, and

the touch detection element of electrostatic capacitance type detecting an external proximity object based on the touch detection drive signal,

wherein the scan drive section includes;

a drive signal control circuit to which a first select signal for selecting one of the common drive electrodes as a target of the first scan drive and a second select signal for selecting one of the common drive electrodes as a target of the second scan drive are supplied,

a first switch allowing the target of the first scan drive to be supplied with the display drive signal,

a second switch allowing the target of the second scan drive to be supplied with the touch detection drive signal, and

a third switch allowing one of the common drive electrodes to be supplied with a direct-current potential,

wherein the drive signal control circuit is configured to;

when the first select signal is at a high level and the second select signal is not at the high level, turn on the first switch and turn off the second switch and the third switch to allow the target of the first scan drive to be supplied with the display drive signal,

when the first select signal is not at the high level and the second select signal is at the high level, turn off the first switch and the third switch and turn on the second switch to allow the target of the second scan drive to be supplied with the touch detection drive signal,

when the first select signal is at the high level and the second select signal is at the high level, turn on the first switch and turn off the second switch and the third switch to allow the target of the first scan drive to be supplied with the display drive signal, and

when the first select signal is not at high level and the second select signal is not at high level, turn off the first switch and the second switch and turn on the third switch to allow one of the common drive electrodes to be supplied with the direct-current potential.

7. A driving method of a display device with a touch detection function, the driving method comprising:

performing a first scan drive operation for performing display, based on a pixel signal and a display drive signal, by allowing a plurality of common drive electrodes to be sequentially supplied with the display drive signal in a time-divisional manner, and allowing pixel electrodes, corresponding to the common drive electrodes which are under the supply of the display drive signal, to be sequentially supplied with the pixel signal in synchronization with the supply of the display drive signal, the plurality of common drive electrodes being arranged side by side to extend in one direction;

performing a second scan drive operation for detecting an external proximity object, based on a detection signal from a touch detection electrode, by allowing the plurality of common drive electrodes to be sequentially supplied with a touch detection drive signal with an amplitude larger than that of the display drive signal in a time-divisional manner, the touch detection electrode forming an electrostatic capacitance with each of the plurality of common drive electrodes; and

controlling a scan drive section including a drive signal control circuit to which a first select signal for selecting one of the common drive electrodes as a target of the first scan drive and a second select signal for selecting one of the common drive electrodes as a target of the second scan drive are supplied, a first switch allowing the target of the first scan drive to be supplied with the display drive signal, and a second switch allowing the target of the second scan drive to be supplied with the touch detection drive signal, and a third switch allowing one of the common drive electrodes to be supplied with a direct-current potential such that;

when the first select signal is at a high level and the second select signal is not at a high level, the drive signal control circuit turns on the first switch and turns off the second switch and the third switch to allow the target of the first scan drive to be supplied with the display drive signal,

when the first select signal is not at the high level and the second select signal is at the high level, the drive signal control circuit turns off the first switch and the third switch and turns on the second switch to allow the target of the second scan drive to be supplied with the detection drive signal,

when the first select signal is at the high level and the second select signal is at the high level, the drive signal control circuit turns on the first switch and turns off the second switch and the third switch to allow the target of the first scan drive to be supplied with the display drive signal, and

when the first select signal is not at high level and the second select signal is not at high level, turn off the first switch and the second switch and turn on the third switch to allow one of the common drive electrodes to be supplied with the direct-current potential.

8. An electronic unit including a display device with a touch detection function and a control section performing operation control with use of the display device with a touch detection function, the display device with a touch detection function comprising:

a plurality of common drive electrodes arranged side by side to extend in one direction;

a display element performing display based on a pixel signal and a display drive signal;

a touch detection element of electrostatic capacitance type detecting an external proximity object, based on a touch detection drive signal with an amplitude larger than that of the display drive signal; and

a scan drive section performing first scan drive and second scan drive, the first scan drive allowing the plurality of common drive electrodes to be sequentially supplied with the display drive signal in a time-divisional manner, and the second scan drive allowing the plurality of common drive electrodes to be sequentially supplied with the touch detection drive signal in a time-divisional manner,

wherein the scan drive section includes;

a drive signal control circuit to which a first select signal for selecting one of the common drive electrodes as a target of the first scan drive and a second select signal for selecting one of the common drive electrodes as a target of the second scan drive are supplied,

a first switch allowing the target of the first scan drive to be supplied with the display drive signal,

a second switch allowing the target of the second scan drive to be supplied with the touch detection drive signal, and

a third switch allowing one of the common drive electrodes to be supplied with a direct-current potential,

wherein the drive signal control circuit is configured to;

when the first select signal is at a high level and the second select signal is not at the high level, turn on the first switch and turn off the second switch and the third switch to allow the target of the first scan drive to be supplied with the display drive signal,

when the first select signal is not at the high level and the second select signal is at the high level, turn off the first switch and the third switch and turn on the second switch to allow the target of the second scan drive to be supplied with the touch detection drive signal,

when the first select signal is at the high level and the second select signal is at the high level, turn on the first switch and turn off the second switch and the third switch to allow the target of the first scan drive to be supplied with the display drive signal, and

when the first select signal is not at high level and the second select signal is not at high level, turn off the first switch and the second switch and turn on the third switch to allow one of the common drive electrodes to be supplied with the direct-current potential.