Organic light-emitting diode display and method of driving the same

Patent metadata

Field	Value
Publication number	US-2017287390-A1
Application number	US-201715472503-A
Country	US
Kind code	A1
Filing date	Mar 29, 2017
Priority date	Mar 29, 2016
Publication date	Oct 5, 2017
Grant date	—

Abstract

An OLED display includes: a plurality of pixel lines each connected to a plurality of pixels, including at least two adjacent pixel lines, each pixel including: a driving thin film transistor (TFT), a first switching TFT, a second switching TFT, and an emission control TFT connected to the driving TFT, a first scan driver controlling a plurality of first switching TFTs for the two pixel lines, a second scan driver controlling a plurality of second switching TFTs for the two pixel lines, and a third scan driver configured so all of a plurality of emission control TFTs for the two pixel lines: are turned on in a programming period, maintain a turn-on state for a particular time of an emission period, and can adjust an on-time duty of the emission period after the particular time.

First claim

What is claimed is:

1 . An organic light-emitting diode (OLED) display, comprising:
a plurality of pixel lines each connected to a plurality of pixels, the plurality of pixel lines including at least an n th pixel line and a (n+1) th pixel line, where n is a natural number, each pixel including:
a driving thin film transistor (TFT);
a first switching TFT connected to the driving TFT;
a second switching TFT connected to the driving TFT; and
an emission control TFT connected to the driving TFT;
a first scan driver configured to control a plurality of first switching TFTs corresponding to the n th pixel line and the (n+1) th pixel line; a second scan driver configured to control a plurality of second switching TFTs corresponding to the n th pixel line and the (n+1) th pixel line; and a third scan driver configured such that all of a plurality of emission control TFTs corresponding to the n th pixel line and the (n+1) th pixel line:
are turned on in a programming period;
maintain a turn-on state for a particular time of an emission period following the programming period; and
are able to adjust an on-time duty of the emission period after the particular time.

2 . The organic light-emitting diode display of claim 1 , wherein:
the n th pixel line and the (n+1) th pixel line are configured to operate at a same on-time duty of the emission period by the third scan driver; the first scan driver includes a plurality of stages configured to drive the n th pixel line and the (n+1) th pixel line; the second scan driver includes a plurality of stages configured to drive the n th pixel line and the (n+1) th pixel line; and the third scan driver includes a plurality of stages configured to drive the n th pixel line and the (n+1) th pixel line.

3 . The organic light-emitting diode display of claim 2 , wherein one of the plurality of stages of the third scan driver is configured to simultaneously drive the n th pixel line and the (n+1) th pixel line.

4 . The organic light-emitting diode display of claim 3 , further comprising a third gate line connecting the plurality of emission control TFTs of the n th pixel line and the (n+1) th pixel line to a corresponding stage of the third scan driver.

5 . The organic light-emitting diode display of claim 3 , wherein the third scan driver is configured to simultaneously apply an emission control signal corresponding to the programming period and the emission period to the emission control TFTs of the n th pixel line and the (n+1) th pixel line.

6 . The organic light-emitting diode display of claim 2 , wherein each of the plurality of stages of the first scan driver is configured to respectively drive the plurality of pixel lines corresponding to the plurality of stages.

7 . The organic light-emitting diode display of claim 6 , further comprising a plurality of first gate lines connecting the first switching TFTs of the n th pixel line and the (n+1) th pixel line to a corresponding stage of the first scan driver.

8 . The organic light-emitting diode display of claim 6 , wherein the first scan driver is configured to sequentially apply first scan control signals corresponding to the programming period and the emission period to the first switching TFTs of the n th pixel line and the (n+1) th pixel line.

9 . The organic light-emitting diode display of claim 2 , wherein one of the plurality of stages of the second scan driver is configured to simultaneously drive the n th pixel line and the (n+1) th pixel line.

10 . The organic light-emitting diode display of claim 9 , further comprising a second gate line connecting the plurality of second switching TFTs of the n th pixel line and the (n+1) th pixel line to a corresponding stage of the second scan driver.

11 . The organic light-emitting diode display of claim 9 , wherein the second scan driver is configured to simultaneously apply a second scan control signal corresponding to the programming period and the emission period to the second switching TFTs of the n th pixel line and the (n+1) th pixel line.

12 . The organic light-emitting diode display of claim 2 , wherein each of the plurality of stages of the second scan driver is configured to respectively drive the plurality of pixel lines corresponding to the plurality of stages.

13 . The organic light-emitting diode display of claim 12 , further comprising a plurality of second gate lines connecting the second switching TFTs of the n th pixel line and the (n+1) th pixel line to a corresponding stage of the second scan driver.

14 . The organic light-emitting diode display of claim 12 , wherein a data voltage applied to the n th pixel line and the (n+1) th pixel line implements an inverse gamma gray level.

15 . The organic light-emitting diode display of claim 2 , wherein the emission control signal of the third scan driver id configured to:
maintain a turn-on state for the particular time after both the first scan control signal and the second scan control signal are turned off; and then be turned off to reduce kickback.

16 . An organic light-emitting diode (OLED) display including a programming period and an emission period, comprising:
a first switching TFT between a gate node of a driving thin film transistor (TFT) and a data line, the first switching TFT being configured to supply a data voltage to the gate node in the programming period; a second switching TFT between a source node of the driving TFT and a reference line, the second switching TFT being configured to bypass a transient current, that is supplied through the driving TFT, to the reference line in the programming period; an emission control TFT between a drain node of the driving TFT and a high potential driving voltage supply line, the emission control TFT being configured to supply a high potential driving voltage to the drain node in the programming period; a storage capacitor between the gate node and the source node, the storage capacitor being configured to charge a gate node-to-source node voltage of the driving TFT in the programming period; and an organic light-emitting diode connected to the source node, the OLED being configured to maintain a non-emission state in the programming period.

17 . The organic light-emitting diode display of claim 16 , wherein:
during the programming period, the emission control TFT is turned on; and during the emission period, the emission control TFT is turned off after a particular time.

18 . The organic light-emitting diode display of claim 17 , wherein the drain node is not in a floating state in the programming period, and is not in a floating state for the at least a particular time of the emission period to reduce kickback.

19 . The organic light-emitting diode display of claim 17 , wherein in the emission period, the emission control TFT maintains a turn-off state for a particular time from the particular time and then is turned on.

20 . The organic light-emitting diode display of claim 19 , wherein in the emission period, the emission control TFT operates in a pulse duty drive in which a variable duty is adjustable.

Assignees

• Lg Display Co Ltd

Inventors

• Lee Hyunsuk
• Kwon Junyoung
• Jin Seungtae

Classifications

• G09G2300/043

  Compensation electrodes or other additional electrodes in matrix displays related to distortions or compensation signals, e.g. for modifying TFT threshold voltage in column driver · CPC title

• G09G3/3291

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

• G09G3/325 Primary

  the data current flowing through the driving transistor during a setting phase, e.g. by using a switch for connecting the driving transistor to the data driver · CPC title

• G09G3/3266 Primary

  Details of drivers for scan electrodes · CPC title

• G09G2300/0809

  Several active elements per pixel in active matrix panels · CPC title