Pixel and organic light emitting display device including the same

Patent metadata

Field	Value
Publication number	US-2019259331-A1
Application number	US-201916279109-A
Country	US
Kind code	A1
Filing date	Feb 19, 2019
Priority date	Feb 19, 2018
Publication date	Aug 22, 2019
Grant date	—

Abstract

A pixel includes an OLED, a driving transistor, first to third transistors, and a first capacitor. The driving transistor controls an amount of current supplied from a first power source to the OLED. The first power source is coupled to a first electrode of the driving transistor. The current corresponds to a voltage of a first node. The first transistor is coupled between a data line and a second node. The first capacitor is coupled between the first node and the second node. The second transistor is coupled between the first node and a second electrode of the driving transistor. The third transistor is coupled between the first node and an initialization power source. A turn-on time of the first and second transistors overlaps that of the third transistor.

First claim

What is claimed is:

1 . A pixel, comprising:
an organic light emitting diode; a driving transistor configured to control an amount of current supplied from a first power source to the organic light emitting diode, wherein the first power source is coupled to a first electrode of the driving transistor, and the current corresponds to a voltage of a first node; a first transistor coupled between a data line and a second node, wherein the first transistor comprises a gate electrode coupled to an ith scan line, and i is a positive integer; a first capacitor coupled between the first node and the second node; a second transistor coupled between the first node and a second electrode of the driving transistor, wherein the second transistor comprises a gate electrode coupled to the ith scan line; and a third transistor coupled between the first node and an initialization power source, wherein the third transistor comprises a gate electrode coupled to an ith initialization control line, wherein a turn-on time of the first and second transistors overlaps a turn-on time of the third transistor.

2 . The pixel of claim 1 , wherein the turn-on time of the first and second transistors is longer than the turn-on time of the third transistor.

3 . The pixel of claim 2 , further comprising:
a fourth transistor coupled between the second node and the initialization power source, wherein the fourth transistor comprises a gate electrode coupled to an (i+2)th initialization control line; and a fifth transistor coupled between the initialization power source and the organic light emitting diode, wherein the fifth transistor comprises a gate electrode coupled to the (i+2)th initialization control line.

4 . The pixel of claim 2 , further comprising:
a fourth transistor coupled between the second node and the initialization power source, wherein the fourth transistor comprises a gate electrode coupled to an (i+3)th initialization control line; and a fifth transistor coupled between the initialization power source and the organic light emitting diode, wherein the fifth transistor comprises a gate electrode coupled to the (i+3)th initialization control line.

5 . The pixel of claim 4 , further comprising:
a sixth transistor coupled between the organic light emitting diode and the second electrode of the driving transistor, wherein the sixth transistor comprises a gate electrode coupled to an emission control line; and a second capacitor coupled between the first node and the first power source.

6 . An organic light emitting display device, comprising:
a plurality of pixels; a plurality of scan lines; a plurality of data lines; a plurality of initialization control lines, wherein the pixels are coupled to the scan lines, the data lines, and the initialization control lines; a scan driver configured to supply a scan signal to the scan lines; a data driver configured to supply a data signal to the data lines; and an initialization driver configured to supply an initialization control signal to the initialization control lines, wherein each of the pixels comprises: an organic light emitting diode; a driving transistor configured to control an amount of current supplied from a first power source to the organic light emitting diode, wherein the first power source is coupled to a first electrode of the driving transistor, and the current corresponds to a voltage of a first node; a first transistor coupled between a data line and a second node, wherein the first transistor comprises a gate electrode coupled to an ith scan line, and i is a positive integer; a first capacitor coupled between the first node and the second node; a second transistor coupled between the first node and a second electrode of the driving transistor, wherein the second transistor comprises a gate electrode coupled to the ith scan line; and a third transistor coupled between the first node and an initialization power source, wherein the third transistor comprises a gate electrode coupled to an ith initialization control line, wherein, during a first period of one frame, the scan signal supplied to the ith scan line and the initialization control signal supplied to the ith initialization control line overlap each other.

7 . The organic light emitting display device of claim 6 , wherein the one frame comprises a second period subsequent to the first period, and the scan driver supplies the scan signal to the ith scan line during the first period and the second period.

8 . The organic light emitting display device of claim 7 , wherein the initialization driver supplies the initialization control signal to the ith initialization control line during the first period.

9 . The organic light emitting display device of claim 8 , wherein the one frame further comprises a third period subsequent to the second period, and the initialization driver supplies the initialization control signal to an (i+2)th initialization control line during the third period.

10 . The organic light emitting display device of claim 8 , wherein the one frame further comprises a third period subsequent to the second period, and the initialization driver supplies the initialization control signal to an (i+3)th initialization control line during the third period.

11 . The organic light emitting display device of claim 10 , further comprising:
an emission driver configured to supply an emission control signal to a plurality of emission control lines coupled to the pixels.

12 . The organic light emitting display device of claim 11 , wherein the one frame further comprises a fourth period subsequent to the third period, and the emission driver supplies the emission control signal to an ith emission control line during the fourth period.

13 . The organic light emitting display device of claim 6 , wherein each of the pixels further comprises:
a fourth transistor coupled between the second node and the initialization power source, wherein the fourth transistor comprises a gate electrode coupled to an (i+2)th initialization control line; and a fifth transistor coupled between the initialization power source and the organic light emitting diode, wherein the fifth transistor comprises a gate electrode coupled to the (i+2)th initialization control line.

14 . The organic light emitting display device of claim 6 , wherein each of the pixels further comprises:
a fourth transistor coupled between the second node and the initialization power source, wherein the fourth transistor comprises a gate electrode coupled to an (i+3)th initialization control line; and a fifth transistor coupled between the initialization power source and the organic light emitting diode, wherein the fifth transistor comprises a gate electrode coupled to the (i+3)th initialization control line.

15 . The organic light emitting display device of claim 14 , wherein each of the pixels further comprises:
a sixth transistor coupled between the organic light emitting diode and the second electrode of the driving transistor, wherein the sixth transistor comprises a gate electrode coupled to an emission control line; and a second capacitor coupled between the first node and the first power source.

16 . The organic light emitting display device of claim 6 , wherein the data driver is coupled to a plurality of output lines, and the organic light emitting display device further comprises a plurality of demultiplexers configured to selectively couple the data lines and the output lines.

17 . The organic light emitting display device of claim

Assignees

• Samsung Display Co Ltd

Inventors

• Na Ji Su

Classifications

• G09G2300/0814

  used for selection purposes, e.g. logical AND for partial update · CPC title

• G09G2320/0626

  for control of overall brightness · CPC title

• G09G2310/08

  Details of timing specific for flat panels, other than clock recovery · CPC title

• G09G2300/0819

  used for counteracting undesired variations, e.g. feedback or autozeroing · CPC title

• G09G3/3233 Primary

  with pixel circuitry controlling the current through the light-emitting element · CPC title