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

Patent metadata

Field	Value
Publication number	US-9671905-B2
Application number	US-201113067658-A
Country	US
Kind code	B2
Filing date	Jun 17, 2011
Priority date	Aug 24, 2010
Publication date	Jun 6, 2017
Grant date	Jun 6, 2017

Abstract

A display device with a touch detection function includes, a plurality of display elements performing display operation based on a pixel signal and a display drive signal, a touch detection element detecting an external proximity object based on a touch detection drive signal, a scan drive section performing display scanning by sequentially supplying the pixel signal and the display drive signal to the plurality of display elements in a time-divisional manner, and the scan drive section supplying the touch detection drive signal to the touch detection element, and a touch detection circuit performing touch detection by sampling a detection result from the touch detection element with a period shorter than a period of the display scanning. The scan drive section supplies the touch detection drive signal to the touch detection element in a touch detection operation period different from a display operation period for performing the display scanning.

First claim

What is claimed is:

1. A display device with a touch detection function comprising:
a plurality of display elements each performing display operation based on a pixel signal and a display drive signal;
a touch detection element detecting an external proximity object based on a touch detection drive signal having a high frequency;
a scan drive section performing display scanning by sequentially supplying the pixel signal and the display drive signal to the plurality of display elements in a time-divisional manner, and the scan drive section supplying the touch detection drive signal to the touch detection element; and
a touch detection circuit detecting a touch detection signal by sampling at a sampling frequency a detection result from the touch detection element with a period shorter than a period of the display scanning, wherein
the scan drive section supplies the touch detection drive signal to the touch detection element in a touch detection operation period different from a display operation period for performing the display scanning during each of a plurality of image frame periods,
the scan drive section performs display scanning of each of the display elements sequentially at a sampling time in synchronization with the touch detection drive signal,
each of the image frame periods includes a plurality of the display operation periods and a plurality of the touch detection operation periods,
a plurality of the touch detections are respectively performed during the plurality of the touch detection operation periods and a plurality of the display operations are respectively performed during the plurality of the display operation periods,
the touch detection signal is in synchronization with the touch detection drive signal, and
the sampling frequency is an integral multiple of a frequency of the touch detection signal.

2. The display device with a touch detection function according to claim 1 , wherein the display drive signal is a rectangular wave signal.

3. The display device with a touch detection function according to claim 1 , wherein
the display operation period is divided into plural periods by a period in which the display scanning is interrupted, and
the touch detection operation period is provided within the period in which the display scanning is interrupted.

4. The display device with a touch detection function according to claim 3 , wherein each of the plural periods corresponds to the display operation of the display elements within a respective display area.

5. The display device with a touch detection function according to claim 1 , wherein
the touch detection drive signal is a rectangular wave signal with a frequency higher than a frequency of the display drive signal, and
the touch detection circuit samples the detection result from the touch detection element at timings in synchronization with the touch detection drive signal.

6. The display device with a touch detection function according to claim 1 , wherein the touch detection element uses a change of an electrostatic capacitance based on proximity or contact of the external proximity object to detect the external proximity object.

7. The display device with a touch detection function according to claim 1 , further comprising:
common drive electrodes arranged in parallel to extend in one direction, wherein
the scan drive section applies the common drive electrodes with the display drive signal in the display operation period, and with the touch detection drive signal in the touch detection operation period.

8. The display device with a touch detection function according to claim 1 , wherein
the touch detection element detects the external proximity object based also on the display drive signal, and
the touch detection circuit performs touch detection by sampling the detection result at timings in synchronization with the display drive signal also in the display operation period.

9. The display device according to claim 1 , wherein the detection operation period corresponds to a blanking period of the display scanning.

10. A display device comprising:
a plurality of display elements;
a detection element; and
a scan drive section performing display scanning by sequentially supplying a display drive signal to the plurality of display elements, and supplying a detection drive signal to the detection element, wherein
the scan drive section supplies the detection drive signal to the detection element in a detection operation period different from a display operation period for performing the display scanning during each of a plurality of image frame periods,
the scan drive section performs display scanning of each of the display elements sequentially at a sampling time in synchronization with the touch detection drive signal,
each of the image frame periods includes a plurality of the display operation periods and a plurality of the touch detection operation periods, and
a plurality of touch detections signals are respectively detected by sampling at a sampling frequency during the plurality of the touch detection operation periods and a plurality of the display operations are respectively performed during the plurality of the display operation periods,
the touch detection signals are each in synchronization with the touch detection drive signal, and
the sampling frequency is an integral multiple of a frequency of the touch detection signal.

11. The display device according to claim 10 , wherein the detection operation period corresponds to a blanking period of the display scanning.

12. The display device according to claim 10 , wherein
the display operation period is divided into plural periods by a period in which the display scanning is interrupted, and
the detection operation period is provided within a period in which the display scanning is interrupted.

13. A control circuit comprising:
a scan drive section performing display scanning by sequentially supplying a pixel signal and a display drive signal to a plurality of display elements in a time-divisional manner, and supplying a touch detection drive signal to a touch detection element detecting an external proximity object; and
a touch detection circuit detecting a touch detection signal by sampling at a sampling frequency a detection result from the touch detection element with a period shorter than a period of the display scanning, wherein
the scan drive section supplies the detection drive signal to the detection element in a detection operation period different from a display operation period for performing the display scanning during each of a plurality of image frame periods,
the scan drive section performs display scanning of each of the display elements sequentially at a sampling time in synchronization with the touch detection drive signal,
each of the image frame periods includes a plurality of the display operation periods and a plurality of the touch detection operation periods,
a plurality of the touch detections are respectively performed during the plurality of the touch detection operation periods and a plurality of the display operations are respectively performed during the plurality of the display operation periods,
the touch detection signal is in synchronization with the touch detection drive signal, and
the sampling frequency is an integral multiple of a frequency of the touch detection signal.

14. A driving method of a display device with a touch detection function comprising:
performing display scanning by sequentially supplying a pixel signal and a display drive signal to a plurality of display elements in a display operation period

Assignees

• Noguchi Koji
• Kida Yoshitoshi
• Azumi kohei
• Japan Display Inc

Inventors

• Noguchi Koji
• Kida Yoshitoshi
• Azumi kohei

Classifications

• G06F2203/04108

  Touchless 2D- 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 without distance measurement in the Z direction · CPC title

• G06F3/0416

  Control or interface arrangements specially adapted for digitisers · CPC title

• G06F3/0412 Primary

  Digitisers structurally integrated in a display · CPC title

• G06F3/044 Primary

  by capacitive means · CPC title

• G06F3/04184

  Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally · CPC title