Pixel circuit and organic light emitting display including the same

Patent metadata

Field	Value
Publication number	US-2016012779-A1
Application number	US-201514703960-A
Country	US
Kind code	A1
Filing date	May 5, 2015
Priority date	Jul 14, 2014
Publication date	Jan 14, 2016
Grant date	—

Abstract

A pixel circuit includes a first organic light emitting diode (OLED), a second OLED, a storage unit coupled to a data line, the storage unit including a first capacitor configured to store at least one of a first data signal and a second data signal received via the data line, a first driver including a second capacitor configured to store the first data signal received via the storage unit, and a first transistor configured to control an amount of a current supplied to the first OLED in response to a voltage stored in the second capacitor, and a second driver including a third capacitor configured to store the second data signal received via the storage unit, and a second transistor configured to control an amount of a current supplied to the second OLED in response to a voltage stored in the third capacitor.

First claim

What is claimed is:

1 . A pixel circuit, comprising:
a first organic light emitting diode; a second organic light emitting diode; a storage unit coupled to a data line, the storage unit comprising a first capacitor configured to store at least one of a first data signal and a second data signal received via the data line; a first driver comprising:
a second capacitor configured to store the first data signal received via the storage unit; and
a first transistor configured to control an amount of current supplied to the first organic light emitting diode in response to a voltage stored in the second capacitor; and
a second driver comprising:
a third capacitor configured to store the second data signal received via the storage unit; and
a second transistor configured to control an amount of current supplied to the second organic light emitting diode in response to a voltage stored in the third capacitor.

2 . The pixel circuit of claim 1 , wherein:
the first organic light emitting diode is configured to emit light in a first direction; the second organic light emitting diode is configured to emit light in a second direction; and the second direction is different from the first direction.

3 . The pixel circuit of claim 2 , wherein:
the pixel circuit is incorporated into a display panel; and the first direction is towards an upper side of the display panel and the second direction is towards a lower side of the panel.

4 . The pixel circuit of claim 1 , wherein:
the storage unit further comprises:
a third transistor coupled between the data line and a first node, the third transistor being configured to be turned on in response to a scan signal being supplied, via a scan line, to a gate electrode of the third transistor;
a fourth transistor coupled between the first node and a gate electrode of the first transistor; and
a fifth transistor coupled between the first node and a gate electrode of the second transistor; and
the first capacitor is coupled between the first node and a first voltage source.

5 . The pixel circuit of claim 4 , wherein configuration of the pixel circuit causes, at least in part, turn-on periods of the third transistor, the fourth transistor, and the fifth transistor to not overlap one another.

6 . The pixel circuit of claim 4 , wherein:
a first electrode of the first transistor is coupled to a first power source, the first transistor being configured to control the amount of current supplied from the first power source to the first organic light emitting diode in response to the voltage stored in the second capacitor; the second capacitor is coupled between the gate electrode of the first transistor and the first power source; and the first driver further comprises a sixth transistor coupled between a second electrode of the first transistor and the first organic light emitting diode, the sixth transistor being configured to operate opposite an operation of the fourth transistor.

7 . The pixel circuit of claim 4 , wherein:
a first electrode of the second transistor is coupled to a first power source, the second transistor being configured to control the amount of current supplied from the first power source to the second organic light emitting diode in response to the voltage stored in the third capacitor; the third capacitor is coupled between the gate electrode of the second transistor and the first power source; and the second driver further comprises a seventh transistor coupled between a second electrode of the second transistor and the second organic light emitting diode, the seventh transistor being configured to operate opposite an operation of the fifth transistor.

8 . An organic light emitting display, comprising:
a pixel comprising a pixel circuit, the pixel circuit being coupled to a scan line and a data line; a first organic light emitting diode and a second organic light emitting diode, the first and second organic light emitting diodes being configured to emit light according to a current supplied from the pixel circuit; a scan driver configured to supply scan signals to the scan line; and a data driver configured to supply at least one of a first data signal and a second data signal to a data line in synchronization with one or more of the scan signals, wherein the pixel circuit is configured to store voltage corresponding to at least one of the first data signal and the second data signal, and wherein the scan driver and the data driver are configured to cause, at least in part, the first organic light emitting diode and the second organic light emitting diode to emit light during a voltage storage period of the pixel circuit.

9 . The organic light emitting display of claim 8 , wherein:
the first organic light emitting diode is configured to emit light in a first direction; the second organic light emitting diode is configured to emit light in a second direction; and the second direction is different from the first direction.

10 . The organic light emitting display of claim 9 , wherein:
the first direction is towards an upper side of the organic light emitting display; the second direction is towards a lower side of organic light emitting display.

11 . The organic light emitting display of claim 8 , further comprising:
a first control line; a second control line; a first light emitting control line; and a second light emitting control line, wherein the first control line, the second control line, the first light emitting control line, and the second light emitting control line are coupled, in association with the scan line and the data line, to the pixel circuit.

12 . The organic light emitting display of claim 11 , wherein:
the data driver is configured to:
supply the first data signal to the pixel circuit during a first period of a frame, the first data signal being associated with the first organic light emitting diode; and
supply the second data signal to the pixel circuit during a second period of the frame, the second data signal being associated with the second organic light emitting diode; and
the scan driver is configured to supply the scan signals to the scan line during the first and second periods.

13 . The organic light emitting display of claim 12 , further comprising:
a control driver configured to:
supply a first control signal to the first control line during a third period of the frame, the third period being between the first period and the second period; and
supply a second control signal to the second control line during a fourth period of the frame, the fourth period being after the second period,
wherein the scan driver is further configured to:
supply a first light emitting control signal to the first light emitting control line during the third period; and
supply a second light emitting control signal to the second light emitting control line during the fourth period.

14 . The organic light emitting display of claim 13 , wherein the pixel circuit comprises:
a storage unit coupled to the data line, the storage unit comprising a first capacitor configured to store at least one of the first data signal and the second data signal; a first driver comprising:
a second capacitor configured to store the first data signal received via the storage unit; and
a first transistor configured to control an amount of current supplied to the first organic light emitting diode in response to a voltage stored in the second to capacitor; and
a second driver comprising:
a third capacitor configured to store the second data signal received via the storage unit; and
a second

Assignees

• Samsung Display Co Ltd

Inventors

• Gu Bon-Seog
• Seo Hae-Kwan

Classifications

• G09G2310/0272

  Details of drivers for data electrodes, the drivers communicating data to the pixels by means of a current · CPC title

• G09G2320/0252

  Improving the response speed · CPC title

• G09G2300/0876

  Supplementary capacities in pixels having special driving circuits and electrodes instead of being connected to common electrode or ground; Use of additional capacitively coupled compensation electrodes · CPC title

• G09G3/3283 Primary

  in which the data driver supplies a variable data current for setting the current through, or the voltage across, the light-emitting elements · CPC title

• G09G3/3266

  Details of drivers for scan electrodes · CPC title