DISPLAY PANEL WITH TOUCH DETECTION FUNCTION, METHOD OF DRIVING THE SAME, DRIVE CIRCUIT, AND ELECTRONIC UNIT

• US 20140253485A1
• Filed: 05/21/2014
• Published: 09/11/2014
• Est. Priority Date: 04/13/2011
• Status: Active Grant

• Current Assignee: Japan Display West Incorporated (Japan Display Incorporated)
• Original Assignee: Japan Display West Incorporated (Japan Display Incorporated)
• Inventors: Kida, Yoshitoshi, Noguchi, Koji, Mizuhashi, Hiroshi, Azumi, Kohei
• Granted Patent: US 9,395,832 B2
• Time in Patent Office: Days
• US Class Current: 345/173
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G06F 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• 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

There are provided a display panel with a touch detection function and a method of driving the same, a drive circuit, as well as an electronic unit, which make it possible to reduce an influence of a disturbance noise. The display panel includes: a signal generation section selecting one pulse period from a plurality of pulse periods prepared beforehand, and generating a synchronization signal including a series of pulses appearing at the selected pulse period; a display section performing display based on the synchronization signal; and a touch detection section performing touch detection operation based on the synchronization signal.

Claims

1. A display panel with a touch detection function, the display panel comprising:

a signal generation section selecting one pulse period from a plurality of pulse periods prepared beforehand, and generating a synchronization signal including a series of pulses appearing at the selected pulse period;

a display section performing display based on the synchronization signal;

a touch detection section performing touch detection operation based on the synchronization signal; and

a signal processing section configured to change the pulse period of a pulse included in the synchronization signal upon detecting a presence or absence of a disturbance noise.

2. The display panel according to claim 1, wherein the display section performs display for one screen in a pulse duration in which the series of pulses continues.

3. The display panel according to claim 2, wherein the touch detection section performs the touch detection operation in the pulse duration.

4. The display panel according to claim 3, wherein the touch detection section performs the touch detection operation, also in a blanking period other than the pulse duration.

5. The display panel according to claim 4, wherein the pulse duration is equal to or shorter than a predetermined length.

6. The display panel according to claim 1, wherein the pulse period is set by a clock count of a base clock, and

the pulse period is changed by changing a clock frequency of the base clock.

7. The display panel according to claim 1, wherein the signal generation section selects the pulse period based on a detection result in the touch detection section.

8. The display panel according to claim 2, wherein the pulse duration is included in a frame period based on an image signal supplied.

9. The display panel according to claim 1, further comprising:

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

a detection electrode arranged side by side to extend in a direction intersecting the drive electrode;

a plurality of pixel electrodes; and

a display element performing display based on a voltage of the drive electrode and a voltage of the pixel electrode,

wherein, based on the synchronization signal, the display section performs display by driving and thereby sequentially scanning a plurality of the display elements per a plurality of the display elements corresponding to each of the drive electrodes, and at timing synchronized with the synchronization signal, the touch detection section sequentially applies a drive signal to the plurality of drive electrodes, and detects a touch event based on a detection signal outputted from the detection electrode.

10. The display panel according to claim 9, wherein the plurality of drive electrodes form a plurality of drive electrode blocks each including a predetermined number of the drive electrodes, and

the touch detection section applies the drive signal to each of the drive electrode blocks, for each drive period including a predetermined number of the pulse periods.

11. The display panel according to claim 10, wherein the touch detection section allows the drive period to be long, when the pulse duration is equal to or shorter than a predetermined length.

12. A method of driving a display panel with a touch detection function, the method comprising:

selecting one pulse period from a plurality of pulse periods prepared beforehand, and generating a synchronization signal that includes a series of pulses appearing at the selected pulse period;

performing display for one screen, and performing touch detection operation, based on the series of pulses of the synchronization signal;

switching display of a screen, for each predetermined frame period; and

changing the pulse period of a pulse included in the synchronization signal upon detecting a presence or absence of a disturbance noise.

13. A drive circuit comprising:

a signal generation section selecting one pulse period from a plurality of pulse periods prepared beforehand, and generating a synchronization signal that includes a series of pulses appearing at the selected pulse period;

a display drive section driving a display panel based on the synchronization signal;

a touch-detection drive section driving a touch panel based on the synchronization signal; and

a signal processing section configured to change the pulse period of a pulse included in the synchronization signal upon detecting a presence or absence of a disturbance noise.

14. An electronic unit including a display panel with a touch detection function, and a control section performing operation control using the display panel, the display panel comprising:

a signal generation section selecting one pulse period from a plurality of pulse periods prepared beforehand, and generating a synchronization signal including a series of pulses appearing at the selected pulse period;

a display section performing display based on the synchronization signal;

a touch detection section performing touch detection operation based on the synchronization signal; and

a signal processing section configured to change the pulse period of a pulse included in the synchronization signal upon detecting a presence or absence of a disturbance noise.