CN113299853A

CN113299853A - OLED display panel

Info

Publication number: CN113299853A
Application number: CN202110517261.0A
Authority: CN
Inventors: 彭久红
Original assignee: Wuhan China Star Optoelectronics Semiconductor Display Technology Co Ltd
Current assignee: Wuhan China Star Optoelectronics Semiconductor Display Technology Co Ltd
Priority date: 2021-05-12
Filing date: 2021-05-12
Publication date: 2021-08-24

Abstract

The invention provides an OLED display panel, which comprises repeating units which are closely arranged, wherein each repeating unit comprises a first sub-pixel, a second sub-pixel and a third sub-pixel which are alternately arranged, and the first sub-pixel, the second sub-pixel and the third sub-pixel are all positioned on the vertex of a virtual regular hexagon; the center of the virtual regular hexagon is provided with a spacer, a safe evaporation distance is arranged between the sub-pixels on the vertexes of the virtual regular hexagon and the spacer, and the adjacent repeating units are closely arranged in a mode of sharing one side edge of the virtual regular hexagon and sharing two sub-pixels on the vertexes of two ends of the side edge; according to the invention, by optimizing the position and arrangement of the spacers, the safe evaporation distance is arranged between the sub-pixels and the spacers, the spacers can be effectively prevented from being scratched by the metal mask plate when the luminescent device is evaporated, and particles falling off from the spacers are prevented from directly falling into the effective luminescent region, so that the production yield of the display panel is improved.

Description

OLED display panel

Technical Field

The invention relates to the technical field of display, in particular to an OLED display panel.

Background

The OLED (Organic Light-Emitting Diode) display panel has excellent characteristics of self-luminescence, no need of a backlight source, high contrast, thin thickness, wide viewing angle, fast reaction speed, applicability to a flexible panel, wide temperature range, simple structure and process, and the like, and is receiving more and more attention.

The spacer in the existing display panel is manufactured on a pixel definition layer, and the main purpose is to prevent a fine metal mask plate from directly contacting with a pixel when an OLED material is evaporated, so that the pixel film layer is prevented from being scratched by the metal mask plate. As shown in fig. 1 and 2, a conventional display panel includes a plurality of sub-pixel structures and spacers, the pixel structures are closed ring structures, and waste chips falling off from the spacers fall into the edges of the pixel ring structures to generate small display black dots (black shading structures), which affects the light emitting quality.

In summary, a new OLED display panel needs to be provided to solve the problem that when viewed from a top view in the above technology, a sub-pixel structure and an adjacent spacer have an overlapping position, and when the spacer is scratched by a metal mask plate, scraps falling off from the spacer fall into an edge of the sub-pixel structure, so that black dots appear when the sub-pixel emits light, and display quality is affected.

Disclosure of Invention

The invention provides an OLED display panel, which can solve the problem that in the prior art, when viewed from a top view, a sub-pixel structure and an adjacent spacer are at an overlapped position, and when the spacer is scratched by a metal mask plate, scraps falling off from the spacer fall into the edge of the sub-pixel structure, so that black spots appear when sub-pixels emit light, and the display quality is influenced.

The technical scheme provided by the invention is as follows:

the embodiment of the invention provides an OLED display panel, which comprises repeating units which are closely arranged, wherein each repeating unit comprises a first sub-pixel, a second sub-pixel and a third sub-pixel which are alternately arranged, and the first sub-pixel, the second sub-pixel and the third sub-pixel are all positioned on the vertex of a virtual regular hexagon.

The center of the virtual regular hexagon is provided with a spacer, a safe evaporation distance is arranged between the sub-pixels on the vertexes of the virtual regular hexagon and the spacer, and the adjacent repeating units are closely arranged in a mode of sharing one side edge of the virtual regular hexagon and sharing two sub-pixels on the vertexes of two ends of the side edge.

According to a preferred embodiment of the present invention, the first sub-pixel, the second sub-pixel and the third sub-pixel are three sub-pixels with different colors.

According to a preferred embodiment of the present invention, the repeating unit includes two of the virtual regular hexagons, and at most two of the spacers are disposed on the two of the virtual regular hexagons.

According to a preferred embodiment of the present invention, in one virtual regular hexagon, the spacer is located at the center of a triangle formed by connecting the centers of the three third sub-pixels.

According to a preferred embodiment of the present invention, two vertexes on any one side of the virtual regular hexagon are respectively provided with two different color sub-pixels.

According to a preferred embodiment of the present invention, in the display area of the display panel, the first sub-pixels, the second sub-pixels, and the third sub-pixels are arranged in rows in the horizontal direction and alternately arranged in the vertical direction.

According to a preferred embodiment of the present invention, the number ratio of the first sub-pixel, the second sub-pixel and the third sub-pixel in the entire display area is 1:1: 2.

According to a preferred embodiment of the present invention, the length of the side of the virtual regular hexagon is a, the spacer is a cylinder, and the diameter of the spacer is less than or equal to one half a; the safe evaporation distance is annular, the width of the annular is less than or equal to one half a, and the sub-pixel is positioned in the range with the vertex as the center and the radius as a.

According to a preferred embodiment of the present invention, the display panel includes a substrate, a driving circuit layer on the substrate, a planarization layer on the driving circuit layer, a pixel defining layer on the planarization layer, and a light emitting device in a pixel opening of the pixel defining layer.

The light-emitting device comprises an anode, a hole injection layer positioned on the anode, a hole transport layer positioned on the hole injection layer, a light-emitting material layer positioned on the hole transport layer, an electron transport layer positioned on the light-emitting material layer, an electron injection layer positioned on the electron transport layer, and a cathode positioned on the electron injection layer.

The pixel definition layer is provided with the spacer, one spacer is arranged between two adjacent light-emitting devices and between two adjacent light-emitting devices, and the safe evaporation distance is arranged between the spacer and the edge of an effective light-emitting area of each light-emitting device.

According to a preferred embodiment of the present invention, the first sub-pixel, the second sub-pixel and the third sub-pixel are all circular or square, and the first sub-pixel, the second sub-pixel and the third sub-pixel are an R sub-pixel, a G sub-pixel and a B sub-pixel, respectively.

The invention has the beneficial effects that: the embodiment of the invention provides an OLED display panel, which comprises repeating units which are closely arranged, wherein each repeating unit comprises a first sub-pixel, a second sub-pixel and a third sub-pixel which are alternately arranged, and the first sub-pixel, the second sub-pixel and the third sub-pixel are all positioned on the vertex of a virtual regular hexagon; the center of the virtual regular hexagon is provided with a spacer, a safe evaporation distance is arranged between the sub-pixels on the vertexes of the virtual regular hexagon and the spacer, and the adjacent repeating units are closely arranged in a mode of sharing one side edge of the virtual regular hexagon and sharing two sub-pixels on the vertexes of two ends of the side edge; according to the invention, by optimizing the position and arrangement of the spacers, the safe evaporation distance is arranged between the sub-pixels and the spacers, the spacers can be effectively prevented from being scratched by the metal mask plate when the luminescent device is evaporated, and particles falling off from the spacers are prevented from directly falling into the effective luminescent region, so that the production yield of the display panel is improved.

Drawings

In order to illustrate the embodiments or the technical solutions in the prior art more clearly, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the invention, and it is obvious for a person skilled in the art that other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 and 2 are schematic diagrams of a structure for generating black dots by a sub-pixel in the prior art.

Fig. 3 to 7 are schematic views of sub-pixel structures of a display panel according to the present invention.

Fig. 8 is a schematic view of a film structure of a display panel according to the present invention.

Fig. 9 is a schematic view illustrating a process for preparing a luminescent material film layer of a display panel according to the present invention.

Detailed Description

The following description of the various embodiments refers to the accompanying drawings that illustrate specific embodiments in which the invention may be practiced. The directional terms mentioned in the present invention, such as [ upper ], [ lower ], [ front ], [ rear ], [ left ], [ right ], [ inner ], [ outer ], [ side ], are only referring to the directions of the attached drawings. Accordingly, the directional terms used are used for explanation and understanding of the present invention, and are not used for limiting the present invention. In the drawings, elements having similar structures are denoted by the same reference numerals, and broken lines in the drawings indicate that the elements do not exist in the structures, and only the shapes and positions of the structures are explained.

The invention aims at the problem that in the prior art, when the spacer is scratched by a metal mask plate, scraps falling off from the spacer fall into the edge of the sub-pixel structure, so that black spots appear when the sub-pixel emits light, and the display quality is affected, wherein the sub-pixel structure and the adjacent spacer are at the overlapped position in a top view.

As shown in fig. 3 and 4, the display region of the OLED display panel is provided with closely arranged repeating units 110, the repeating unit 110 is a minimum repeating unit, adjacent repeating units are closely arranged in a manner of sharing one side of a virtual regular hexagon and sharing two sub-pixels located at vertices at both ends of the side, and the repeating units 110 overlap each other to cover the display region. Each repeating unit 110 includes two virtual regular hexagons, such as virtual regular hexagon 11 and virtual regular hexagon 12, each vertex of virtual regular hexagon 11 and virtual regular hexagon 12 is provided with one sub-pixel, and adjacent vertices are provided with sub-pixels of different colors, that is, two vertices on any one side of virtual regular hexagon are respectively provided with sub-pixels of two different colors, thereby realizing low-resolution simulation high resolution. The first sub-pixel 101, the second sub-pixel 102 and the third sub-pixel 103 are sequentially arranged at each vertex of the virtual regular hexagon of this embodiment, the first sub-pixel 101, the second sub-pixel 102 and the third sub-pixel 103 are sub-pixels of three different colors, and the first sub-pixel 101, the second sub-pixel 102 and the third sub-pixel 103 of this embodiment are preferably an R sub-pixel, a G sub-pixel and a B sub-pixel, respectively.

The first sub-pixel 101 is represented by a triangle, the second sub-pixel 102 is represented by a rectangle, and the third sub-pixel 103 is represented by a circle, which does not represent the specific structure of the sub-pixel. The shape of each of the first sub-pixel 101, the second sub-pixel 102, and the third sub-pixel 103 is circular or square, and is not limited herein, but the shape of the first sub-pixel 101 may be triangular, the shape of the second sub-pixel 102 may be rectangular, and the shape of the third sub-pixel 103 may be circular, in order to distinguish the light emitting ranges of the sub-pixels of different colors.

In one repeating unit 110, the number of first sub-pixels 101 is 3, the number of second sub-pixels 102 is 2, and the number of third sub-pixels 103 is 5, but the ratio of the number of first sub-pixels 101, second sub-pixels 102, and third sub-pixels 103 in the entire display area is preferably 1:1: 2. In the display area of the display panel, the first sub-pixels 101, the second sub-pixels 102, and the third sub-pixels 103 are arranged in rows in the lateral direction and alternately arranged in the longitudinal direction.

The repeating units comprise two virtual regular hexagons, at most two spacers are arranged on the two virtual regular hexagons, and the spacers may not be arranged on part of the repeating units. As shown in figures 5 and 6 of the drawings,

the center position of the virtual regular hexagon is provided with a spacer 13, the vertex of the virtual regular hexagon is provided with a first sub-pixel 101, a second sub-pixel 102 and a third sub-pixel 103, the first sub-pixel 101, the second sub-pixel 102 and the third sub-pixel 103 are all circular, the first sub-pixel 101, the second sub-pixel 102 and the third sub-pixel 103 are not directly contacted with the spacer 13, an annular buffer area 14 exists, the width of the annular buffer area 14 is a safe evaporation distance, particles falling off from the spacer are prevented from directly falling into an effective light emitting area, and therefore the production yield of the display panel is improved. The side length of the virtual regular hexagon is a, the spacer is a cylinder, and the diameter of the spacer is less than or equal to one half a; the safe evaporation distance is annular, the width of the annular is less than or equal to one half a, and the sub-pixel is positioned in the range of the radius a by taking the vertex as the center.

In the case of fig. 7 in combination with fig. 6, as shown in fig. 7, the spacer 13 is located at the center of a triangle formed by connecting the centers of the three third sub-pixels 103 in a virtual regular hexagon.

FIG. 8 is a schematic cross-sectional view A1-A2 of FIG. 1. As shown in fig. 8, the OLED display panel includes a substrate 120, a driving circuit layer 121 on the substrate 120, a planarization layer 122 on the driving circuit layer 121, a pixel defining layer 123 on the planarization layer 122, and a light emitting device of a pixel opening on the pixel defining layer 123; the pixel defining layer 123 includes a first sub-pixel defining layer 1231, a second sub-pixel defining layer 1232, and a third sub-pixel defining layer 1233, wherein one light emitting device is formed between adjacent two of the first sub-pixel defining layer 1231, the second sub-pixel defining layer 1232, and the third sub-pixel defining layer 1233. Each light-emitting device comprises an anode, a hole injection layer positioned on the anode, a hole transport layer positioned on the hole injection layer, a light-emitting material layer positioned on the hole transport layer, an electron transport layer positioned on the light-emitting material layer, an electron injection layer positioned on the electron transport layer, and a cathode positioned on the electron injection layer. The pixel defining layer 123 is provided with a spacer 128, a spacer 128 is disposed between two adjacent light emitting devices, and a safety evaporation distance h1 is disposed between the spacer 128 and the edge of the effective light emitting area of the light emitting device.

In the pixel groove of this embodiment, an anode layer 124, a hole layer 125 on the anode layer, a light emitting material layer 126 on the hole layer 125, an electron layer 127 on the light emitting material layer 126, a cathode layer (not shown) on the electron layer 127, and an encapsulation layer (not shown) on the cathode layer are sequentially disposed. The hole layer 125 includes a hole injection layer and a hole transport layer, and the electron layer 127 includes an electron transport layer and an electron injection layer.

The anode layer 124 includes a first anode electrode 1241, a second anode electrode 1242, and a third anode electrode 1243, the hole layer 125 includes a first hole layer 1251, a second hole layer 1252, and a third hole layer 1253, the light emitting material layer 126 includes a first light emitting material layer 1261, a second light emitting material layer 1262, and a third light emitting material layer 1263, and the electron layer 127 includes a first electron layer 1271, a second electron layer 1272, and a third electron layer 1273, wherein the first anode electrode 1241, the first hole layer 1251, the first light emitting material layer 1261, the first electron layer 1271, and a portion of the cathode form a first light emitting device that emits green light. The second anode electrode 1242, the second hole layer 1252, the second light emitting material layer 1262, the second electron layer 1272, and a portion of the cathode form a second light emitting device, and the second light emitting device emits red light. The third anode electrode 1243, the third hole layer 1253, the third light emitting material layer 1263, the third electron layer 1273, and a portion of the cathode form a third light emitting device, which emits blue light. In this embodiment, the first hole layer 1251 and the second hole layer 1252 are in a spaced-apart state, the first electron layer 1271 and the second electron layer 1272 are in a spaced-apart state, the second hole layer 1252 and the third hole layer 1253 are in a communicating state, and the second electron layer 1272 and the third electron layer 1273 are in a communicating state.

In addition, the substrate 120 of the present embodiment is a flexible substrate, and the substrate is preferably a yellow and transparent polyimide laminated film layer; the driving circuit layer 121 includes a buffer layer on the flexible substrate, and a plurality of driving thin film transistors disposed on the buffer layer. The plurality of driving thin film transistors are provided with a planarization layer 122, the planarization layer 122 is provided with a via hole, and the anode layer 124 is electrically connected with the drain electrodes of the driving thin film transistors through the via hole. The source electrode of the driving thin film transistor is connected with the positive electrode of an external power supply, the corresponding driving chip is attached to the flexible printed circuit board, the negative electrode of the external power supply transmits a corresponding electrical signal to the power wiring layer through the binding area, and finally the power wiring layer transmits the corresponding electrical signal to the negative electrode, so that the required voltage is provided for the light-emitting device.

As shown in fig. 9, the metal mask 129 is located on the spacer 128, and after the light emitting material layer in one region is evaporated, the metal mask 129 needs to be moved, and the edge of the mask may scratch the film layer of the spacer 128, thereby generating a waste. As shown in fig. 9, when the green sub-pixel light-emitting material layer 1261 is deposited, the mask thereof shows that the film layer of the spacer 128 only contacts with the central region of the mask, and the safety distance from the edge of the mask opening region avoids the rubbing of the spacer 128, thereby improving the production yield of the light-emitting device.

In summary, although the present invention has been described with reference to the preferred embodiments, the above-described preferred embodiments are not intended to limit the present invention, and those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, therefore, the scope of the present invention shall be determined by the appended claims.

Claims

1. An OLED display panel is characterized by comprising closely arranged repeating units, wherein each repeating unit comprises a first sub-pixel, a second sub-pixel and a third sub-pixel which are alternately arranged, and the first sub-pixel, the second sub-pixel and the third sub-pixel are all positioned on the vertex of a virtual regular hexagon;

2. The OLED display panel of claim 1, wherein the first, second and third subpixels are subpixels of three different colors.

3. The OLED display panel of claim 2, wherein the repeating unit comprises two of the virtual regular hexagons, and a maximum of two of the spacers are disposed on the two of the virtual regular hexagons.

4. The OLED display panel according to claim 3, wherein the spacer is located at the center of a triangle formed by connecting the centers of the three third sub-pixels in one virtual regular hexagon.

5. The OLED display panel according to claim 3, wherein two vertexes on any one side of the virtual regular hexagon are respectively provided with two different color sub-pixels.

6. The OLED display panel of claim 1, wherein the first sub-pixels, the second sub-pixels and the third sub-pixels are arranged in rows in a transverse direction and alternately arranged in a longitudinal direction in a display area of the display panel.

7. The OLED display panel of claim 6, wherein the number ratio of the first sub-pixel, the second sub-pixel and the third sub-pixel in the entire display area is 1:1: 2.

8. The OLED display panel according to claim 1, wherein the virtual regular hexagon has a side length of a, the spacer is a cylinder, and the diameter of the spacer is less than or equal to one half a; the safe evaporation distance is annular, the width of the annular is less than or equal to one half a, and the sub-pixel is positioned in the range with the vertex as the center and the radius as a.

9. The OLED display panel of claim 1, wherein the display panel comprises a substrate, a driving circuit layer on the substrate, a planarization layer on the driving circuit layer, a pixel defining layer on the planarization layer, and a light emitting device in a pixel opening of the pixel defining layer;

the light-emitting device comprises an anode, a hole injection layer positioned on the anode, a hole transport layer positioned on the hole injection layer, a light-emitting material layer positioned on the hole transport layer, an electron transport layer positioned on the light-emitting material layer, an electron injection layer positioned on the electron transport layer, and a cathode positioned on the electron injection layer;

10. The OLED display panel of claim 1, wherein the first sub-pixel, the second sub-pixel and the third sub-pixel are all circular or square in shape, and the first sub-pixel, the second sub-pixel and the third sub-pixel are respectively an R sub-pixel, a G sub-pixel and a B sub-pixel.