Display apparatus, drive circuit, driving method and electronic apparatus

• US 9,588,631 B2
• Filed: 08/12/2015
• Issued: 03/07/2017
• Est. Priority Date: 10/12/2011
• Status: Active Grant

• Current Assignee: Japan Display Incorporated
• Original Assignee: Japan Display Incorporated
• Inventors: Noguchi, Koji, Kida, Yoshitoshi, Azumi, Kohei
• Primary Examiner(s): Cerullo, Liliana
• Application Number:
  US14/824,829
• Publication Number:
  US 20150346883A1
• Time in Patent Office: 573 Days
• US Class Current: 1/1
• 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 3/04184 Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally
• 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 3/047 using sets of wires, e.g. crossed wires
• CPC Class Codes: G09G 2300/0426 Layout of electrodes and connections
• CPC Class Codes: G09G 2310/0202 Addressing of scan or signal lines
• CPC Class Codes: G09G 2310/0297 Special arrangements with multiplexing or demultiplexing of display data in the drivers for data electrodes, in a pre-processing circuitry delivering display data to said drivers or in the matrix panel, e.g. multiplexing plural data signals to one D/A converter or demultiplexing the D/A converter output to multiple columns
• CPC Class Codes: G09G 2310/08 Details of timing specific for flat panels, other than clock recovery
• CPC Class Codes: G09G 3/36 using liquid crystals
• CPC Class Codes: G09G 3/3677 suitable for active matrices only
• CPC Class Codes: G09G 3/3685 Details of drivers for data electrodes
• CPC Class Codes: G09G 5/003 Details of a display terminal, the details relating to the control arrangement of the display terminal and to the interfaces thereto specific for a CRT G09G1/165; for a flat panel G09G3/2092
• CPC Class Codes: G09G 5/18 Timing circuits for raster scan displays specially adapted for television H04N ; synchronisation between the display unit and other display units, videodisc player G09G5/12

Abstract

A display apparatus includes: a display device; a touch detection device; and a driver unit driving the display device so as to sequentially display M horizontal lines in each of plural unit drive periods forming one frame period and driving the touch detection device in N touch detection periods provided in each unit drive period, in which N is lower than M.

Claims

1. A display apparatus comprising:

a plurality of display elements including pixel electrodes;

a plurality of drive electrodes facing the pixel electrodes; and

;

a plurality of touch detection elements including touch detection electrodes facing the drive electrodes;

a driver unit configured to cause the display elements to display images and to cause the touch detection elements to detect a touch; and

a control unit configured to cause the driver unit to;

divide a frame in which images are displayed by the display elements, into a plurality of display periods; and

determine a touch detection period between adjacent display periods in one frame, the touch detection period being a period in which the touch detection elements detect a touch,

wherein the driver unit is configured to apply an AC driving signal to the drive electrode to be a target of the touch detection operation during the touch detection period so that the touch detection element makes the touch detection, is configured to apply a DC drive signal to all the drive electrodes, and is configured to apply a pixel signal to the pixel electrode to be a target of the display operation during the display period so that the display elements display an image, and

wherein the control unit is configured to control the driver unit to have a first period in which the display period and the touch detection period are provided alternately, and a second period in which the display period is provided continuously.

2. The display apparatus according to claim 1, wherein

the touch detection elements include drive electrodes and touch detection electrodes,

a capacitance is formed between the touch detection electrodes and the drive electrodes, and

the driver unit is configured to apply an AC drive signal which causes at least one transition to the drive electrodes in each touch detection period.

3. The display apparatus according to claim 2,

wherein the AC drive signal has at least one pulse.

4. The display apparatus according to claim 3,

wherein a pulse width of the AC drive signal in one touch detection period is different from a pulse width of the AC drive signal in another touch detection period.

5. The display apparatus according to claim 3,

wherein a pulse position of the AC drive signal in one touch detection period is different from a pulse position of the AC drive signal in another touch detection period.

6. The display apparatus according to claim 2, further comprising:

a detection unit configured to sample a detection signal that is output from the touch detection electrodes at timings before and after respective transitions of the AC drive signal to detect a touch based on variations in sampling results in respective transitions.

7. The display apparatus according to claim 2,

wherein the control unit is configured to apply the AC drive signal in units of a given number of respective drive electrodes.

8. The display apparatus according to claim 2,

further comprising a liquid crystal layer,

wherein the pixel electrodes are formed between the liquid crystal layer and the drive electrodes, or are arranged opposite to the liquid crystal layer so as to sandwich the drive electrodes.

9. The display apparatus according to claim 8,

wherein the control unit is configured to apply a display drive signal to the drive electrodes in periods other than the touch detection period.

10. The display apparatus according to claim 2,

further comprising a liquid crystal layer,

wherein the pixel electrodes are arranged opposite to the drive electrodes so as to sandwich the liquid crystal layer.

11. The display apparatus according to claim 1, wherein

during the touch detection period, the driver unit is configured to apply the AC driving signal to the drive electrode to be a target of the touch detection operation and apply the DC driving signal to the drive electrode other than the target of the touch detection operation so that the touch detection electrode of which the AC driving signal is applied makes the touch detection.

12. A driver unit configured to:

cause a plurality of display elements including pixel electrodes to display images by driving a plurality of drive electrodes that face the pixel electrodes;

cause a plurality of touch detection elements which face the drive electrodes to detect a touch by driving the drive electrodes;

divide a frame in which images is displayed by the display elements, into a plurality of display periods;

determine a touch detection period between adjacent display periods in one frame, the touch detection period being a period in which the touch detection elements detect a touch;

apply an AC driving signal to the drive electrode to be a target of the touch detection operation during the touch detection period so that the touch detection element makes the touch detection; and

apply a DC drive signal to all the drive electrodes, and apply a pixel signal to the pixel electrode to be a target of the display operation during the display period so that the display elements display an image,

wherein the control unit is configured to control the driver unit to have a first period in which the display period and the touch detection period are provided alternately, and a second period in which the display period is provided continuously.

13. The driver unit according to claim 12, wherein

the plurality of the display elements form one display screen, and

the driver circuit drives:

in the touch detection period, none of the display elements of the one display screen; and

in the display period, none of the touch detection elements.