Pixel and organic light emitting display device having the same

Patent metadata

Field	Value
Publication number	US-10650739-B2
Application number	US-201715704578-A
Country	US
Kind code	B2
Filing date	Sep 14, 2017
Priority date	Mar 30, 2017
Publication date	May 12, 2020
Grant date	May 12, 2020

Abstract

An organic light emitting display device includes a plurality of pixels. Each of the pixels includes an organic light emitting diode, first to third transistors, a storage capacitor, and a first capacitor. The second transistor includes a gate electrode receiving a first scan signal, a first electrode receiving a data signal, and a second electrode connected to a first electrode of the first transistor. The third transistor includes a gate electrode receiving a second scan signal, a first electrode connected to a second electrode of the first transistor, and a second electrode connected to a gate electrode of the first transistor. The storage capacitor includes a first electrode receiving a power voltage and a second electrode connected to the gate electrode of the first transistor. The first capacitor includes a first electrode connected to the gate electrode of the third transistor and a second electrode receiving the power voltage.

First claim

What is claimed is:

1. An organic light emitting display device comprising a plurality of pixels,
wherein each of the plurality of pixels includes:
an organic light emitting diode (OLED);
a first transistor including a gate electrode, a first electrode, and a second electrode, the first transistor being a driving transistor which controls a current flowing into the OLED based on a data signal;
a second transistor including a gate electrode receiving a first scan signal, a first electrode receiving the data signal, and a second electrode connected to the first electrode of the first transistor;
a third transistor including a gate electrode receiving a second scan signal, a first electrode connected to the second electrode of the first transistor, and a second electrode connected to the gate electrode of the first transistor;
a storage capacitor including a first electrode receiving a first power voltage and a second electrode connected to the gate electrode of the first transistor; and
a first capacitor including a first electrode connected to the gate electrode of the third transistor and a second electrode receiving the first power voltage.

2. The organic light emitting display device of claim 1 , wherein
the first transistor and the third transistor are metal-oxide-semiconductor (MOS) transistors, and
a channel type of the first transistor is different from a channel type of the third transistor.

3. The organic light emitting display device of claim 1 , wherein
the second transistor and the third transistor are MOS transistors, and
a channel type of the second transistor is different from a channel type of the third transistor, and wherein
the second scan signal is a signal that is the first scan signal inverted.

4. The organic light emitting display device of claim 1 , wherein each of the plurality of pixels further includes:
a fourth transistor including a gate electrode receiving a third scan signal, a first electrode receiving an initialization voltage that differs from the first power voltage, and a second electrode connected to the gate electrode of the first transistor;
a fifth transistor including a gate electrode receiving an emission control signal, a first electrode receiving the first power voltage, and a second electrode connected to the first electrode of the first transistor;
a sixth transistor including a gate electrode receiving the emission control signal, a first electrode connected to the second electrode of the first transistor, and a second electrode connected to a first electrode of the OLED; and
a seventh transistor including a gate electrode receiving a fourth scan signal, a first electrode receiving the initialization voltage, and a second electrode connected to the first electrode of the OLED.

5. The organic light emitting display device of claim 4 ,
wherein the first transistor, the fifth transistor, and the sixth transistor are p-channel MOS transistors, and
wherein the fourth transistor and the seventh transistor are n-channel MOS transistors.

6. The organic light emitting display device of claim 4 ,
wherein the first transistor is a p-channel MOS transistor, and
wherein the second through seventh transistors are n-channel MOS transistors.

7. The organic light emitting display device of claim 1 , wherein each of the plurality of pixels further includes:
a second capacitor including a first electrode connected to the gate electrode of the first transistor and a second electrode connected to the gate electrode of the third transistor.

8. The organic light emitting display device of claim 7 , wherein a first capacitance of the first capacitor is larger than a second capacitance of the second capacitor.

9. A pixel comprising:
an organic light emitting diode (OLED);
a first transistor including a gate electrode, a first electrode, and a second electrode, the first transistor being a driving transistor which controls a current flowing into the OLED based on a data signal;
a second transistor including a gate electrode receiving a first scan signal, a first electrode receiving the data signal, and a second electrode connected to the first electrode of the first transistor;
a third transistor including a gate electrode receiving a second scan signal, a first electrode connected to the second electrode of the first transistor, and a second electrode connected to the gate electrode of the first transistor;
a storage capacitor including a first electrode receiving a first power voltage and a second electrode connected to the gate electrode of the first transistor; and
a first capacitor including a first electrode connected to the gate electrode of the third transistor and a second electrode receiving the first power voltage.

10. The pixel of claim 9 , wherein
the first transistor and the third transistor are metal-oxide-semiconductor (MOS) transistors, and
a channel type of the first transistor is different from a channel type of the third transistor.

11. The pixel of claim 9 ,
wherein the second transistor and the third transistor are MOS transistors, and
a channel type of the second transistor is different from a channel type of the third transistor, and
wherein the second scan signal is a signal that is the first scan signal inverted.

Assignees

• Samsung Display Co Ltd

Inventors

• Kim Dongwoo
• Kim Sunghwan
• Shin Kyoungju
• Lee Cheol-Gon
• Lim Sang-Uk

Classifications

• G09G3/3233 Primary

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

• G09G3/3283

  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

• G09G2320/0219

  Reducing feedthrough effects in active matrix panels, i.e. voltage changes on the scan electrode influencing the pixel voltage due to capacitive coupling · CPC title

• G09G3/3266

  Details of drivers for scan electrodes · CPC title

• G09G2300/0852

  being a dynamic memory with more than one capacitor · CPC title