Display panel, light-emitting device, and driving method thereof

Patent metadata

Field	Value
Publication number	US-11569407-B2
Application number	US-201916488621-A
Country	US
Kind code	B2
Filing date	Jun 10, 2019
Priority date	May 23, 2019
Publication date	Jan 31, 2023
Grant date	Jan 31, 2023

Abstract

A display panel, a light-emitting device, and a driving method thereof are provided. The light-emitting device includes a substrate, and a first electrode, a first light-emitting unit, a connecting layer, a second light-emitting unit, and a second electrode stacked up sequentially on the substrate. Polarities of the first electrode and the second electrode are opposite and reverse periodically in order that the first light-emitting unit and the second light-emitting unit illuminate alternately.

First claim

What is claimed is:

1. A light-emitting device, comprising: a substrate, and a first electrode, a first light-emitting unit, a connecting layer, a second light-emitting unit, and a second electrode stacked up sequentially on the substrate;
wherein polarities of the first electrode and the second electrode are opposite and reverse periodically in order that the first light-emitting unit and the second light-emitting unit illuminate alternately;
wherein one of the first light-emitting unit and the second light-emitting unit is of a first structure comprising a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting layer, a hole blocking layer, an electron transport layer, and an electron injection layer stacked up from bottom to top, and wherein the other one of the first light-emitting unit and the second light-emitting unit is of a second structure comprising the electron injection layer, the electron transport layer, the hole blocking layer, the light-emitting layer, the electron blocking layer, the hole transport layer, and the hole injection layer stacked up from bottom to top;
wherein the connecting layer is of a laminated structure, wherein the laminated structure comprises a first negative doped layer, a first positive doped layer, and a second negative doped layer stacked up from bottom to top when the first light-emitting unit is of the first structure and when the second light-emitting unit is of the second structure, and wherein the laminated structure comprises a second positive doped layer, a third negative doped layer, and a third positive doped layer stacked up from bottom to top when the first light-emitting unit is of the second structure and when the second light-emitting unit is of the first structure.

2. The light-emitting device of claim 1 , wherein the connecting layer comprises at least one material selected from a group consisting of Li, Rb, Cs, Mg, and Ag when the first light-emitting unit is of the first structure and when the second light-emitting unit is of the second structure.

3. The light-emitting device of claim 1 , wherein the connecting layer comprises at least one material selected from a group consisting of FeCl 3 , F 4 -TCNQ, WO 3 , MoO 3 , and HAT-CN when the first light-emitting unit is of the second structure and when the second light-emitting unit is of the first structure.

4. The light-emitting device of claim 1 , wherein materials of the first, second, and third positive doped layers comprise a hole transporting material doped with positive dope comprising at least one material selected from a group consisting of FeCl 3 , F 4 -TCNQ, WO 3 , MoO 3 , and HAT-CN, and wherein materials of the first, second, and third negative doped layers comprise an electron transporting material doped with negative dope comprising at least one material selected from a group consisting of Li, Rb, Cs, Mg, and Ag.

5. The light-emitting device of claim 1 , wherein a material of the light-emitting layer comprises perovskite.

6. The light-emitting device of claim 1 , wherein a thickness of the connecting layer is between 5 and 100 nm.

7. The light-emitting device of claim 1 , wherein switching frequencies of the polarities of the first electrode and the second electrode are 60 Hz.

8. A method of driving a light-emitting device comprising a substrate, and a first electrode, a first light-emitting unit, a connecting layer, a second light-emitting unit, and a second electrode stacked up sequentially on the substrate, the method comprising:
inputting a common voltage to one of the first electrode and the second electrode, and inputting a gray level voltage to the other one of the first electrode and the second electrode, wherein the common voltage and the gray level voltage are different in order that the first light-emitting unit or the second light-emitting unit illuminates; and
measuring time and judging whether duration of measuring time reaches a predetermined periodic duration, and if the duration of measuring time does, acquiring the present gray level voltage, adjusting the present gray level voltage based on the common voltage, and returning to the step of measuring time after clearing the measured time to zero in order that the first light-emitting unit and the second light-emitting unit illuminate alternately.

9. The method of claim 8 , wherein the step of adjusting the present gray level voltage based on the common voltage comprises:
acquiring a difference value by computing the difference between the present gray level voltage and the common voltage;
acquiring a target gray level voltage by computing the difference between the common voltage and the difference value; and
adjusting the present gray level voltage to the target gray level voltage.

10. A display panel, comprising: a light-emitting device comprising a substrate, and a first electrode, a first light-emitting unit, a connecting layer, a second light-emitting unit, and a second electrode stacked up sequentially on the substrate;
wherein polarities of the first electrode and the second electrode are opposite and reverse periodically in order that the first light-emitting unit and the second light-emitting unit illuminate alternately;
wherein one of the first light-emitting unit and the second light-emitting unit is of a first structure comprising a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting layer, a hole blocking layer, an electron transport layer, and an electron injection layer stacked up from bottom to top, and wherein the other one of the first light-emitting unit and the second light-emitting unit is of a second structure comprising the electron injection layer, the electron transport layer, the hole blocking layer, the light-emitting layer, the electron blocking layer, the hole transport layer, and the hole injection layer stacked up from bottom to top;
wherein the connecting layer is of a laminated structure, wherein the laminated structure comprises a first negative doped layer, a first positive doped layer, and a second negative doped layer stacked up from bottom to top when the first light-emitting unit is of the first structure and when the second light-emitting unit is of the second structure, and wherein the laminated structure comprises a second positive doped layer, a third negative doped layer, and a third positive doped layer stacked up from bottom to top when the first light-emitting unit is of the second structure and when the second light-emitting unit is of the first structure.

11. The display panel of claim 10 , wherein the connecting layer comprises at least one material selected from a group consisting of Li, Rb, Cs, Mg, and Ag when the first light-emitting unit is of the first structure and when the second light-emitting unit is of the second structure.

12. The display panel of claim 10 , wherein the connecting layer comprises at least one material selected from a group consisting of FeCl 3 , F 4 -TCNQ, WO 3 , MoO 3 , and HAT-CN when the first light-emitting unit is of the second structure and when the second light-emitting unit is of the first structure.

13. The display panel of claim 10 , wherein materials of the first, second, and third positive doped layers comprise a hole transporting material doped with positive dope comprising at least one material selected from a group consisting of FeCl 3 , F 4 -TCNQ, WO 3 , MoO 3 , and HAT-CN, and wherein materials of the first, second, and third negative doped layers comprise an electron transporting material doped with negative dope comprising at least one material selected from a group consisting of Li, Rb, Cs, Mg, and Ag.

Assignees

• Shenzhen China Star Optoelectronics Semiconductor Display Tech Co Ltd

Inventors

• Yin Yongming
• Lee Chiayu
• Hsu Chunche

Classifications

• H01L51/5278

  Electricity · mapped topic

• G09G2320/045

  Compensation of drifts in the characteristics of light emitting or modulating elements · CPC title

• G09G2310/08

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

• G09G2310/0254

  Control of polarity reversal in general, other than for liquid crystal displays · CPC title

• G09G3/34

  by control of light from an independent source · CPC title