CN107731865B

CN107731865B - OLED display device

Info

Publication number: CN107731865B
Application number: CN201710434485.9A
Authority: CN
Inventors: 翁裕复; 林俊文; 刘家麟
Original assignee: Hongfujin Precision Industry Shenzhen Co Ltd; Hon Hai Precision Industry Co Ltd
Current assignee: Hongfujin Precision Industry Shenzhen Co Ltd; Hon Hai Precision Industry Co Ltd
Priority date: 2016-08-12
Filing date: 2017-06-09
Publication date: 2021-04-06
Anticipated expiration: 2037-06-09
Also published as: TW201818537A; TWI656634B; CN107731865A

Abstract

An OLED display device comprises a first electrode layer, a light emitting layer and a second electrode layer which are sequentially stacked, wherein the second electrode layer forms an anode of the light emitting layer, and the first electrode layer is multiplexed into a cathode of the light emitting layer, a touch sensing electrode and a pressure sensing electrode of the OLED display device; the OLED display device also comprises a third electrode layer, and the first electrode layer and the third electrode layer form a pressure sensing module.

Description

OLED display device

Technical Field

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

Background

Compared with a Liquid Crystal Display (LCD), an Organic Light-emitting Diode (OLED) Display has the advantages of self-luminescence, wide viewing angle, fast response speed, and the like. In the field of mobile terminal applications, the OLED display has begun to replace the conventional LCD, and the OLED display device integrated with the touch function has become a research focus in the display field of today, and with the general application of the pressure sensing function in the field of mobile terminals, there is an urgent need to provide a technical solution for a touch display device integrated with the pressure sensing function at the same time.

Disclosure of Invention

In view of the above, there is a need for an OLED display device that integrates both touch control and pressure sensing functions.

The cathode of the OLED display device is simultaneously multiplexed into the cathode of the light emitting layer, the touch sensing electrode and the pressure sensing electrode of the OLED display device, and the OLED display device is ingenious in design and simple in structure.

Drawings

Fig. 1 is an exploded view of an OLED display device according to a first embodiment of the present invention.

Fig. 2 is a schematic plan layout of a pixel unit.

Fig. 3 is a schematic plan layout view of the first electrode layer in fig. 1.

Fig. 4 is a schematic cross-sectional view of the OLED display device in fig. 1.

FIG. 5 is a schematic cross-sectional view of an OLED display device according to a second embodiment of the present invention.

FIG. 6 is a schematic cross-sectional view of an OLED display device according to a third embodiment of the present invention.

Fig. 7 is a schematic plan layout view of the first electrode layer of the OLED display device according to the fourth to sixth embodiments of the present invention.

Description of the main elements

The following detailed description will further illustrate the invention in conjunction with the above-described figures.

Detailed Description

Referring to fig. 1, fig. 1 is an exploded view of an OLED display device 1 according to a first embodiment of the invention. The OLED display device 1 includes a first substrate 11, a first electrode layer 12, a light emitting layer 13, a second electrode layer 14, a Thin Film Transistor (TFT) layer 15, a second substrate 16, and a third electrode layer 17, which are sequentially stacked. The light-emitting layer 13 includes a plurality of light-emitting units 130 distributed in an array, the second electrode layer 14 is used as an anode of the light-emitting layer 13, and includes a plurality of pixel electrodes 140 arranged at intervals in an array, and each light-emitting unit 130 is disposed corresponding to one pixel electrode 140. In general, the light-emitting layer 13 includes an electron injection layer, an electron transport layer, an organic light-emitting layer, a hole transport layer, and a hole injection layer (not shown), which are stacked, wherein the electron injection layer is closer to the first electrode layer 12, and the hole injection layer is closer to the second electrode layer 14. The first electrode layer 12 is reused as a cathode of the light emitting layer 13, a touch sensing electrode and a pressure sensing electrode of the OLED display device 1, and the first electrode layer 12 and the third electrode layer 17 form a pressure sensing module. The first electrode layer 12 is a cathode of the light emitting layer 13, and the second electrode layer 14 is an anode of the light emitting layer 13. The thin-film transistor layer 15 includes a plurality of TFTs (not shown), each of which is electrically connected to one of the pixel electrodes 140 to supply a driving current to the pixel electrode 140. In the present embodiment, the first electrode layer 12 is multiplexed into the cathode of the light emitting layer 13, the touch sensing electrode and the pressure sensing electrode of the OLED display device 1 by time-division operation.

Each of the pixel electrodes 140 is disposed corresponding to one of the light emitting units 130. Referring to fig. 2, each of the plurality of pixel electrodes 140 and the corresponding light emitting unit 130 form a pixel unit 150, and the OLED display device 1 includes a plurality of pixel units 150. Fig. 2 is a schematic plan layout diagram of the pixel unit 150. The plurality of pixel units 150 are arranged in an array along a first direction D1 and a second direction D2. In the present embodiment, one pixel unit 150 includes three pixel electrodes 140, and the three pixel electrodes 140 respectively control the light emitting units 130 corresponding to the three primary colors (R, G, B) to emit light. In the present embodiment, the first direction D1 is substantially perpendicular to the second direction D2.

Referring to fig. 3, fig. 3 is a schematic plan layout view of the first electrode layer 12. The first electrode layer 12 includes a plurality of first electrodes 121 arranged in an array along a first direction D1 and a second direction D2. The distribution of the plurality of first electrodes 121 has a corresponding relationship with the distribution of the plurality of pixel units 150. In the present embodiment, the length of each first electrode 121 in the first direction D1 is equivalent to the total span length of the N pixel units 150 along the first direction D1, and the length L2 of each first electrode 121 in the second direction D2 is equivalent to the length of one pixel unit 150 along the second direction D2. Each first electrode 121 is connected to the IC circuit 10 through a wire 123 to form a self-contained touch sensing electrode. Wherein N is a natural number. The value of N depends on the touch resolution of the OLED display device 1, and the higher the touch resolution is, the higher the distribution density of the first electrodes 121 is, and the smaller the value of N is. The value of N determines the area of one first electrode 121 and the distance P between the centers of two adjacent touch sensing electrodes, wherein the larger N is, the larger P is. In this embodiment, the value range of N is 40 or more and 60 or less. The present invention adopts a single-layer self-capacitance touch sensing technology, the IC circuit 10 electrically controls each first electrode 121 through the conducting wire 123, when a conductor (such as a human body) touches the first substrate 11, the amount of charge on the first electrode 121 corresponding to the touched position changes and outputs an electrical signal, and the IC circuit 10 implements a touch sensing function according to the electrical signal.

Referring to fig. 4, fig. 4 is a schematic cross-sectional structure diagram of the OLED display device 1 in fig. 1. In this embodiment, the third electrode layer 17 is a metal frame, i.e. a middle frame of the OLED display device 1, an air gap 18(air gap) exists between the third electrode layer 17 and the second substrate 16, and the first electrode layer 12, the third electrode layer 17 and the air gap 18 cooperate to form a capacitive pressure sensing device 20, so as to implement a pressure sensing function. When the first substrate 11 is pressed, the structure on the third electrode layer 17, that is, the first substrate 11, the first electrode layer 12, the light emitting layer 13, the second electrode layer 14, the thin film transistor layer 15, and the second substrate 16 all deform toward the air gap 18, the distance between the first electrode layer 12 and the third electrode layer 17 changes, so that the capacitance value of the capacitor formed by the first electrode layer 12 and the third electrode layer 17 changes, and the pressure sensing device 20 performs pressure sensing according to the change of the capacitance value and outputs a pressure sensing signal.

The position of the pressure sensing device 20 in the OLED display device 1 can be variously changed.

Referring to fig. 5, fig. 5 is a schematic cross-sectional view of an OLED display device 2 according to a second embodiment of the invention. The structure of the OLED display device 2 is substantially the same as that of the OLED display device 1, and the difference is mainly in the position of the third electrode layer 17. In the present embodiment, the third electrode layer 17 is not formed by the middle frame of the OLED display device 2, but is a semiconductor transparent conductive film, which may be Indium Tin Oxide (ITO), disposed between the first substrate 11 and the first electrode layer 12. The OLED display device 2 further includes an elastic insulating layer 19, and the third electrode layer 17, the elastic insulating layer 19 and the first electrode layer 12 are sequentially stacked to form the pressure sensing device 20. When the first substrate 11 is pressed, the elastic insulation layer 19 is pressed and deformed, so that a capacitance value of a capacitor formed by the first electrode layer 12 and the third electrode layer 17 changes, and the pressure sensing device 20 performs pressure sensing according to the change of the capacitance value to output a pressure sensing signal.

Referring to fig. 6, fig. 6 is a schematic cross-sectional view of an OLED display device 3 according to a third embodiment of the invention. The structure of the OLED display device 3 is substantially the same as that of the OLED display device 2, differing mainly in the location of the third electrode layer 17 and the elastic insulation layer 19. The third electrode layer 17 is likewise not formed by the middle frame of the OLED display device 3, but is a transparent, electrically conductive metal oxide layer arranged between the thin-film transistor layer 15 and the second substrate 16. The elastic insulation layer 19 is disposed between the thin film transistor layer 15 and the third electrode layer 17. The pressure sensing device 20 is composed of the first electrode layer 12, the elastic insulation layer 19 and the third electrode layer 17. When the first substrate 11 is pressed, the elastic insulation layer 19 is pressed and deformed, so that a capacitance value of a capacitor formed by the first electrode 121 and the third electrode layer 17 changes, and the pressure sensing device 20 performs pressure sensing according to the change of the capacitance value to output a pressure sensing signal.

Alternatively, referring to fig. 7, fig. 7 is a schematic plan layout view of the first electrode layer 12 of the OLED display device (not shown) according to the fourth to sixth embodiments of the present invention. The OLED display device of the fourth embodiment has substantially the same structure as the OLED display device 1, and the difference is mainly the structure of the first electrode layer 12. The OLED display device of the fifth embodiment has substantially the same structure as the OLED display device 2, and differs mainly in the structure of the first electrode layer 12. The OLED display device of the sixth embodiment has substantially the same structure as the OLED display device 3, and differs mainly in the structure of the first electrode layer 12. The first electrode layer 12 in the OLED display devices of the fourth to sixth embodiments has the same structure, and the structure of the first electrode layer 12 in the OLED display devices of the fourth to sixth embodiments will be described in detail below. For convenience of explanation, the same elements as those in the previous embodiment are denoted by the same reference numerals, and are not described in detail below.

In the OLED display devices of the fourth to sixth embodiments, the first electrode layer 12 further includes a plurality of second electrodes 122, the first electrode layer 12 is divided into a plurality of first electrodes 121 and a plurality of second electrodes 122 by physical partitioning, the plurality of first electrodes 121 serve as touch sensing electrodes and pressure sensing electrodes, and the plurality of second electrodes 122 serve as cathodes of the light emitting layer 13.

Specifically, the plurality of second electrodes 122 are disposed in the same layer as the plurality of first electrodes 121, and are formed of the same conductive material layer. Each of the second electrodes 122 has an elongated shape extending in the first direction D1. The plurality of second electrodes 122 are substantially parallel and spaced apart along the second direction D2. In the second direction D2, one first electrode 121 is sandwiched between every two adjacent second electrodes 122, that is, the plurality of second electrodes 122 and the plurality of first electrodes 121 are alternately arranged at intervals in the second direction D2. Each of the second electrodes 122 and each of the first electrodes 121 are disposed to be insulated from each other.

Referring to fig. 2 and fig. 7, the distribution of the first electrode layer 12 corresponds to the distribution of the pixel units 150. The total span length L3 of each first electrode 121 and the second electrode 122 adjacent thereto in the second direction D2 in the second direction D2 is equivalent to the length L of one pixel unit 150 in the second direction D2 on the second electrode layer 14, wherein the length of each first electrode 121 in the second direction D2 is equivalent to one third of the length L1 of each pixel unit 150 in the second direction D2. The length of each first electrode 121 in the first direction D1 is equivalent to the total span length of the N pixel units 150 on the second electrode layer 14 along the first direction D1, and accordingly, each adjacent N first electrodes 121 in the second direction D2 are electrically connected by a wire 123 to form a touch electrode 120 (as shown by a dashed line frame in fig. 7), and each touch electrode 120 is connected to the IC circuit 10 by the wire 123. Wherein N is a natural number. In this embodiment, the value range of N is 40 or more and 60 or less. The value of N depends on the touch resolution of the OLED display device 1, and the higher the touch resolution is, the higher the distribution density of the first electrodes 121 is, and the smaller the value of N is. The value of N determines the distribution area of one touch electrode 120 and the distance P between the centers of two adjacent touch sensing electrodes), and the larger N is, the larger P is.

In the OLED display devices of the fourth to sixth embodiments, the first electrode layer 12 is divided into different regions, so that the display function of the OLED display device 1 can be realized simultaneously with the touch function (or the pressure sensing function), and the display effect is not affected by the touch function (or the pressure sensing function) without sacrificing the working time of the display stage. Specifically, the plurality of first electrodes 121 serve as a touch sensing electrode and a pressure sensing electrode by time division multiplexing, and in a touch sensing stage, the plurality of first electrodes 121 serve as touch electrodes for self-contained touch sensing to realize a touch sensing function; in the pressure sensing stage, the plurality of first electrodes 121 cooperate with the third electrode layer 17 to realize the pressure sensing function. The plurality of second electrodes 122 serve as cathodes of the light emitting layer 13.

While preferred embodiments of the present invention have been described above, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. It is intended that the present invention also includes such changes and modifications as fall within the scope and range of equivalents of the claims.

Claims

1. An OLED display device comprises a first electrode layer, a light-emitting layer and a second electrode layer which are sequentially stacked, wherein the second electrode layer forms an anode of the light-emitting layer, and the OLED display device is characterized in that: the first electrode layer is reused as a cathode of the light emitting layer, a touch sensing electrode and a pressure sensing electrode of the OLED display device; the OLED display device also comprises a third electrode layer, the first electrode layer and the third electrode layer form a pressure sensing module, the first electrode layer comprises a plurality of first electrodes and second electrodes which are arranged at intervals in an array manner along a first direction and a second direction, the plurality of first electrodes and the plurality of second electrodes are alternately arranged at intervals in the second direction, the plurality of second electrodes and the plurality of first electrodes are arranged at the same layer and are insulated, the plurality of second electrodes are cathodes of the light-emitting layer, the plurality of first electrodes are multiplexed into touch sensing electrodes and pressure sensing electrodes of the OLED display device in a time-sharing manner, the second electrode layer comprises a plurality of pixel electrodes which are arranged in an array manner along the first direction and the second direction, the light-emitting layer comprises a plurality of light-emitting units, each pixel electrode is arranged corresponding to one light-emitting unit, each plurality of pixel electrodes and the corresponding light-emitting units form one pixel unit, the length of each first electrode in the first direction is equivalent to the total span length of the N pixel units along the first direction, and the OLED display device further comprises an elastic insulating layer which is arranged between the first electrode and the third electrode.

2. The OLED display device claimed in claim 1, wherein: the OLED display device also comprises a first substrate, wherein the first substrate, the third electrode layer and the elastic insulating layer are sequentially stacked on one side of the first electrode layer, which is far away from the second electrode layer, and the elastic insulating layer is closer to the first electrode layer; the plurality of first electrodes, the elastic insulating layer and the third electrode layer form the pressure sensing module.

3. The OLED display device claimed in claim 1, wherein: the OLED display device also comprises a first substrate, wherein the elastic insulating layer, the third electrode layer and the first substrate are sequentially stacked on one side of the second electrode layer, which is far away from the first electrode layer, and the elastic insulating layer is closer to the second electrode layer; the first electrode layer, the elastic insulation layer and the third electrode layer form the pressure sensing module.

4. The OLED display device claimed in claim 1, wherein: the value range of N is a natural number of 40 or more and 60 or less.

5. The OLED display device claimed in claim 1, wherein: the total spanning length of each first electrode and the second electrode adjacent to the first electrode in the second direction is equivalent to the length of one pixel unit in the second direction.