US-12620354-B2 - Light emitting display device with duty driving

US12620354B2US 12620354 B2US12620354 B2US 12620354B2US-12620354-B2

Abstract

A display device includes a light emitting diode disposed in a pixel; and an emission control transistor disposed in the pixel, and controlling on and off of the light emitting diode according to an emission control signal for each frame, wherein the frame includes a first duty cycle to a K-th duty cycle each of which sets an on-duty period and an off-duty period, and wherein the on-duty period of the first duty cycle is longer than the on-duty period of each of the second to K-th duty cycles.

Inventors

Ri YU
Bong-Hwan Kim
Un-Seon LEE

Assignees

LG DISPLAY CO., LTD.

Dates

Publication Date: 20260505
Application Date: 20231218
Priority Date: 20221230

Claims (20)

1 . A display device, comprising: a light emitting diode disposed in a pixel; and an emission control transistor disposed in the pixel, and controlling on and off of the light emitting diode according to an emission control signal for each frame, wherein the frame is divided into a first duty section to a K-th duty section which are arranged according to time order and each of which includes an on-duty period and an off-duty period, wherein the first to K-th duty sections have the same length, wherein the on-duty period of the first duty section is longer than the on-duty period of each of the second to K-th duty sections, wherein the first to K-th duty sections includes the first duty section, the second duty section immediately after the first duty section, and a third duty section immediately after the second duty section, wherein the on-duty period of the first duty section is longer than the on-duty period of each of the second and third duty sections, and wherein in each of the first to K-th duty sections, the on-duty period precedes the off-duty period.
2 . The display device of claim 1 , wherein the on-duty period of the K-th duty section is shorter than the on-duty period of each of the first to (K−1)-th duty sections.
3 . The display device of claim 1 , wherein the on-duty periods of the second to K-th duty sections sequentially decrease.
4 . The display device of claim 1 , wherein the on-duty periods of the second to K-th duty sections are the same.
5 . The display device of claim 1 , wherein some of the on-duty periods of the second to K-th duty sections are the same.
6 . The display device of claim 1 , wherein the on-duty periods of the second to K-th duty sections sequentially increase.
7 . The display device of claim 1 , wherein the on-duty periods of the second to K-th duty sections are different from each other without sequentially decreasing or increasing.
8 . A display device, comprising: a light emitting diode; and an emission control transistor connected to the light emitting diode, and controlling on and off of the light emitting diode for each frame, wherein the frame is divided into a first duty section to a K-th duty section which are arranged according to time order and each of which includes an on-duty period and an off-duty period, wherein the first to K-th duty sections have the same length, wherein the on-duty period of the first duty section is longer than the on-duty period of each of the second to K-th duty sections, wherein the first to K-th duty sections includes the first duty section, the second duty section immediately after the first duty section, and a third duty section immediately after the second duty section, wherein the on-duty period of the first duty section is longer than the on-duty period of each of the second and third duty sections, and wherein in each of the first to K-th duty sections, the on-duty period precedes the off-duty period.
9 . The display device of claim 8 , wherein the on-duty period of the K-th duty section is shorter than the on-duty period of each of the first to (K−1)-th duty sections.
10 . The display device of claim 8 , wherein the on-duty periods of the second to K-th duty sections sequentially decrease.
11 . The display device of claim 8 , wherein the on-duty periods of the second to K-th duty sections are the same.
12 . The display device of claim 8 , wherein some of the on-duty periods of the second to K-th duty sections are the same.
13 . The display device of claim 8 , wherein the on-duty periods of the second to K-th duty sections sequentially increase.
14 . The display device of claim 8 , wherein the on-duty periods of the second to K-th duty sections are different from each other without sequentially decreasing or increasing.
15 . A display method, comprising: receiving a frame of a video signal; and dividing the frame into a first section to a K-th section having a same time duration, the first section to the K-th section arranged according to time order, wherein a duty cycle of the first section is larger than that of the K-th section, wherein the first to K-th sections includes the first section, a second section immediately after the first section, and a third section immediately after the second section, wherein the duty cycle of the first section is longer than a duty cycle of each of the second and third sections, wherein each of the first to K-th sections includes an on-duty period and an off-duty period, and wherein in each of the first to K-th sections, the on-duty period precedes the off-duty period.
16 . The display method of claim 15 , wherein the duty cycle of the K-th section is shorter than the duty cycle of each of the first to (K−1)-th sections.
17 . The display method of claim 15 , wherein the duty cycles of the second to K-th sections sequentially decrease.
18 . The display method of claim 15 , wherein the duty cycles of the second to K-th sections are the same.
19 . The display method of claim 15 , wherein the duty cycles of the second to K-th sections sequentially increase.
20 . The display method of claim 15 , wherein the duty cycles of the second to K-th sections are different from each other without sequentially decreasing or increasing.

Description

CROSS-REFERENCE TO RELATED APPLICATION The present application claims the priority of Korean Patent Application No. 10-2022-0190481 filed on Dec. 30, 2022, which is hereby incorporated by reference in its entirety. BACKGROUND Field of the Disclosure The present disclosure relates to a light emitting display device. Description of the Background As the information society develops, a demand for display devices for displaying images have increased in various forms, and in recent years, various flat display devices such as light emitting display devices and liquid crystal display devices have been used. The light emitting display device uses a light emission control signal to control an emission of a light emitting diode. To improve a stain or the like, a so-called duty driving is performed in which one frame is divided into a plurality of duty cycles and the light emitting diode is repeatedly turned on/off. However, in the duty driving, when displaying a low luminance, an anode charging of the light emitting diode is delayed, and light may not be properly emitted at an initial duty cycle of the frame. Accordingly, there may occur a problem that when switching frames, a large difference in luminance occurs and is recognized as a flicker. SUMMARY An advantage of the present disclosure is to provide a display device that may improve occurrence of flicker when switching frames in a duty driving. Additional features and advantages of the disclosure will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the disclosure. These and other advantages of the disclosure will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings. To achieve these and other advantages and in accordance with the purpose of the present disclosure, as embodied and broadly described herein, a display device includes: a light emitting diode disposed in a pixel; and an emission control transistor that disposed in the pixel, and controls on and off of the light emitting diode according to an emission control signal for each frame, wherein the frame includes a first duty cycle to a K-th duty cycle each of sets an on-duty period and an off-duty period, and wherein the on-duty period of the first duty cycle is longer than the on-duty period of each of the second to K-th duty cycles. In another aspect, a display device includes: a light emitting diode; an emission control transistor that is connected to the light emitting diode, and controls on and off of the light emitting diode for each frame, wherein the frame includes a first duty cycle to a K-th duty cycle each of sets an on-duty period and an off-duty period, and wherein the on-duty period of the first duty cycle is longer than the on-duty period of each of the second to K-th duty cycles. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the disclosure as claimed. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of this specification, illustrate aspects of the disclosure and together with the description serve to explain the principles of the disclosure. In the drawings: FIG. 1 is a view schematically illustrating a display device according to a first aspect of the present disclosure; FIG. 2 is a circuit diagram schematically illustrating an example of a pixel according to a first aspect of the present disclosure; FIG. 3 is a timing diagram schematically illustrating an example of driving signals that drive a pixel of FIG. 2; FIG. 4 is a view illustrating a configuration of a gate driving portion of a display device according to a first aspect of the present disclosure; FIG. 5 is a circuit diagram illustrating a configuration of an emission control signal driving portion of a gate driving portion according to a first aspect of the present disclosure; FIG. 6 is a cross-sectional view schematically illustrating an example of a cross-sectional structure of a display panel according to a first aspect of the present disclosure; FIG. 7 is a view schematically illustrating an example of an emission control signal that implements a duty driving according to a first aspect of the present disclosure; FIG. 8 is a view illustrating a simulation result of a luminance waveform of a light emitting display device of a comparative example; FIG. 9 is a view illustrating a simulation result of a luminance waveform of a light emitting display device according to a first aspect of the present disclosure; FIG. 10 is a view illustrating another example of an emission control signal that implements a duty driving according to a first aspect of the present disclosure; and FIG. 11 is a view