Light-emitting display device

Patent metadata

Field	Value
Publication number	US-12288507-B2
Application number	US-202318395287-A
Country	US
Kind code	B2
Filing date	Dec 22, 2023
Priority date	Dec 31, 2019
Publication date	Apr 29, 2025
Grant date	Apr 29, 2025

Abstract

A light emitting display device includes a display panel including a first pixel group including a plurality of pixels in 2N rows. The light emitting display device further includes a second pixel group disposed subsequent to the first pixel group and including a plurality of pixels in 2N rows. The light emitting display device further includes an emission signal unit including a first emission stage for applying the same first emission signal to the first pixel group and a second emission stage for applying the same second emission signal to the second pixel group. In a first frame, a falling time of the first emission signal and a rising time of the second emission signal are different from each other.

First claim

The invention claimed is:

1. An inorganic light emitting display device, comprising:
a display panel including:
a substrate including a display area and a non-display area, the display area being defined by a plurality of pixels;
a plurality of data lines and a plurality of scan lines arranged to cross each other on the substrate and respectively connected to the plurality of pixels;
a first pixel group including at least two pixels in 2N rows among the plurality of pixels; and
a second pixel group disposed subsequent to the first pixel group and including at least two other pixels in 2N rows among the plurality of pixels; and

an emission signal circuit including:
a first emission stage configured to apply a same first emission signal to the first pixel group; and
a second emission stage configured to apply a same second emission signal to the second pixel group,

wherein, in a first frame, a falling time of the first emission signal and a rising time of the second emission signal are different from each other,
wherein the falling time of the first emission signal is a time at which the first emission signal is inverted from a high voltage to a low voltage,
wherein the rising time of the second emission signal is a time at which the second emission signal is inverted from the low voltage to the high voltage,
wherein, in a second frame, the falling time of the first emission signal is slower than the rising time of the second emission signal,
wherein the falling time of the first emission signal in the first frame and the falling time of the first emission signal in the second frame are different from each other, and
wherein the rising time of the second emission signal in the first frame and the rising time of the second emission signal in the second frame are different from each other.

2. The inorganic light emitting display device of claim 1 , wherein, in the first frame, the falling time of the first emission signal is slower than the rising time of the second emission signal.

3. The inorganic light emitting display device of claim 2 , wherein, in the first frame, the falling time of the first emission signal is slower than the rising time of the second emission signal by a data signal application time period for one row.

4. The inorganic light emitting display device of claim 1 , wherein the first emission stage and the second emission stage are configured to apply the first emission signal and the second emission signal, respectively, to alternately drive the first frame and the second frame.

5. The inorganic light emitting display device of claim 1 , wherein:
in the first frame, the falling time of the first emission signal is identical to a start time of a data signal application time period for a first row of the second pixel group, and
in the first frame, the rising time of the second emission signal is identical to a start time of a data signal application time period for a last row of the first pixel group.

6. The inorganic light emitting display device of claim 5 , wherein:
in the second frame, the falling time of the first emission signal is identical to a start time of a data signal application time period for a second row of the second pixel group, and
in the second frame, the rising time of the second emission signal is identical to a start time of a data signal application time period for the first row of the second pixel group.

7. The inorganic light emitting display device of claim 1 , further comprising:
a plurality of emission signal lines connecting the emission signal circuit and the plurality of pixels; and
a plurality of high potential voltage lines configured to apply a high potential voltage to the plurality of pixels,
wherein the plurality of emission signal lines and the plurality of high potential voltage lines overlap and cross each other.

8. The inorganic light emitting display device of claim 7 , wherein when the emission signal transmitted through the plurality of emission signal lines falls or rises, a ripple occurs in the high potential voltage transmitted through the high potential voltage line.

9. The inorganic light emitting display device of claim 1 , further comprising:
a gate driver including a scan signal circuit configured to apply a scan signal to the plurality of pixels.

10. The inorganic light emitting display device of claim 9 , wherein each of the plurality of pixels includes:
a first transistor including a gate electrode connected to an input terminal of a first scan signal, a source electrode connected to the data line supplying the data voltage, and a drain electrode connected to a first node;
a second transistor including a source electrode connected to a third node, a drain electrode connected to a second node, and a gate electrode connected to the input terminal of the first scan signal;
a third transistor including a gate electrode connected to an input terminal of an emission signal, a source electrode connected to the first node, and a drain electrode connected to an input terminal of a reference voltage;
a fourth transistor including a source electrode connected to the third node, a drain electrode connected to a fourth node, and a gate electrode connected to the input terminal of the emission signal;
a fifth transistor including a drain electrode connected to the fourth node, a source electrode connected to the input terminal of the reference voltage, and a gate electrode connected to an input terminal of a second scan signal;
a driving transistor including a source electrode connected to an input terminal of a high potential voltage, a gate electrode connected to the second node, and a drain electrode connected to the third node, the driving transistor being configured to control a driving current according to a voltage between the source electrode and the gate electrode of the driving transistor;
a storage capacitor including a first electrode connected to the first node and a second electrode connected to the second node; and
a light emitting element (LED) including an anode connected to the fourth node and a cathode connected to an input terminal of a low potential voltage, the LED being configured to emit light based on the driving current supplied from the driving transistor.

11. The inorganic light emitting display device of claim 10 , wherein the high voltage of the first and second emission signals is a gate-off signal, and the low voltage of the first and second emission signals is a gate-on signal.

12. The inorganic light emitting display device of claim 10 , wherein:
the first transistor is configured to apply the data voltage supplied from the data line to the first node in response to the first scan signal,
the second transistor is configured to diode-connect the gate electrode and the drain electrode of the driving transistor in response to the first scan signal,
the third transistor is configured to apply the reference voltage to the first node in response to the emission signal,
the fourth transistor is configured to form a current path between the third node and the fourth node in response to the emission signal, and
the fifth transistor is configured to apply the reference voltage to the fourth node in response to the second scan signal.

13. The inorganic light emitting display device of claim 1 , wherein the display panel is configured to alternately display the first frame in which dark lines are visible and the second frame in which bright lines are visible at a boundary between the first pixel group and the second pixel group.

14. The inorganic light emitting display device of claim 1 , wherein:
the display

Assignees

• Lg Display Co Ltd

Inventors

• Kim Jeong Ki
• Park Joon Young
• Park Jae Woo
• Cho Sung Min
• Kim Hyeong Kyu

Classifications

• G09G2320/0233

  Improving the luminance or brightness uniformity across the screen · 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

• G09G2310/067

  Special waveforms for scanning, where no circuit details of the gate driver are given · CPC title

• G09G2310/08

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

• G09G2310/0267

  Details of drivers for scan electrodes, other than drivers for liquid crystal, plasma or OLED displays · CPC title