Electroluminescent element and electroluminescent display device having the same

Abstract

An electroluminescent element and an electroluminescent display device that achieve high brightness and high resolution are proposed. The electroluminescent element and the electroluminescent display device include: a first light-emitting element provided with a first light emitter that emits light of a first color and a second light emitter that emits light of a second color different from the first color, the first light emitter and the second light emitter being arranged adjacent to each other; and a second light-emitting element provided with a third light emitter that is arranged to overlap with the first light emitter and the second light emitter and emits light of a third color different from the first color and the second color, wherein the light of the first color and the second color emitted from the first light-emitting element is emitted through the second light-emitting element.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of Korean Patent Application No. 10-2019-0168028, filed on Dec. 16, 2019, which is hereby incorporated by reference in its entirety for all purposes as if fully set forth herein. Technical Field

[0003] The present disclosure relates to an electroluminescent element and an electroluminescent display device provided with the electroluminescent element, and more particularly to an electroluminescent element and an electroluminescent display device capable of achieving high brightness and high resolution. Background Art

[0004] Recently, various flat panel display devices with light weight and small size have been developed, which overcome the shortcomings of cathode ray tubes (CRTs). Examples of such flat panel display devices include liquid crystal displays (LCDs), field emission displays (FEDs), plasma display panels (PDPs), electroluminescent displays, etc.

[0005] Among these flat panel display devices, an electroluminescent display device is a self-luminous display device that excites an organic compound to emit light, and therefore does not require a backlight used in an LCD, thereby having the effect of being able to reduce weight, reduce thickness, and simplify the manufacturing process at the same time. In addition, since the organic electroluminescent display device has the characteristics of being manufactured at a relatively low temperature, having a high response speed of less than 1 ms, and having low power consumption, a wide viewing angle, a high contrast, etc., the organic electroluminescent display device has been widely used.

[0006] However, such an electroluminescent display device has a problem of low brightness due to light emission using a single light emitting layer as a configuration for light emission. Summary of the invention

[0007] The present disclosure is to provide an electroluminescent element capable of achieving high brightness and high resolution and an electroluminescent display device having the same.

[0008] In order to achieve the above-mentioned purpose, according to the first feature of the present disclosure, an electroluminescent element includes: a first light-emitting element, which is provided with a first light emitter that emits light of a first color and a second light emitter that emits light of a second color different from the first color, and the first light emitter and the second light emitter are arranged adjacent to each other; and a second light-emitting element, which is provided with a third light emitter, and the third light emitter is arranged to overlap with the first light emitter and the second light emitter and emits light of a third color different from the first color and the second color, wherein the light of the first color and the second color emitted from the first light-emitting element is emitted through the second light-emitting element.

[0009] In order to achieve the above-mentioned purpose, according to the second feature of the present disclosure, an electroluminescent element includes: a first light-emitting element, which is provided with a first light emitter that emits light of a first color and a second light emitter that emits light of a second color different from the first color, and the first light emitter and the second light emitter are arranged to be adjacent to each other; and a second light-emitting element, which is provided with a third light emitter and a fourth light emitter, the third light emitter is arranged to overlap with the first light emitter and emit light of the second color, the fourth light emitter is arranged to overlap with the second light emitter and emit light of the third color, and the third light emitter and the fourth light emitter are arranged to be adjacent to each other, wherein the light emitted from the first light-emitting element is emitted through the second light-emitting element.

[0010] In order to achieve the above-mentioned purpose, according to the third feature of the present disclosure, an electroluminescent element includes: a first light-emitting element, provided with a first light emitter emitting light of a first color, and a color filter layer, which is arranged to overlap with the first light emitter and has a first color filter of a second color different from the first color and a second color filter of a third color different from the first color and the second color, the first color filter and the second color filter being arranged adjacent to each other; and a second light-emitting element, provided with a second light emitter, the second light emitter being arranged to overlap with the first light emitter and the color filter layer and emitting light of a fourth color different from the first color to the third color, wherein the light emitted from the first light-emitting element is emitted through the color filter layer and the second light-emitting element.

[0011] In addition, in order to achieve the above-mentioned purpose, the electroluminescent display device disclosed in the present invention includes: scan lines and data lines, which are arranged to cross each other; a switching thin film transistor, which performs a switching operation on a data signal supplied through the data line in response to a scan signal supplied through the scan line; a storage capacitor, which stores the data signal output from the switching thin film transistor as a data voltage; a driving thin film transistor, which supplies a driving current according to the data voltage stored in the storage capacitor; and an electroluminescent element, which emits light according to the first to third characteristics and according to the driving current.

[0012] According to the electroluminescent display device disclosed herein, by overlapping the first light-emitting element and the second light-emitting element, light emitted from the first light-emitting element is combined with light emitted from the second light-emitting element and emitted to the outside, thereby having the effect of obtaining light with high brightness and high resolution.

[0013] In addition, a single pixel is made to have light of a first color emitted from a first light emitting element and light of a second color different from the first color emitted from a second light emitting element, thereby having the effect of obtaining light with high brightness and high resolution. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 is a block diagram schematically illustrating an electroluminescent display device according to an exemplary embodiment of the present disclosure.

[0015] Figure 2 yes Figure 1 Schematic circuit diagram of a pixel of an electroluminescent display device shown in FIG.

[0016] Figure 3 It is shown Figure 1 An equivalent circuit diagram of an example of a pixel of an electroluminescent display device shown in FIG.

[0017] Figure 4 is a cross-sectional view showing a first example of an electroluminescent element of an electroluminescent display device according to an exemplary embodiment of the present disclosure.

[0018] Figure 5 is a cross-sectional view illustrating a second example of the electroluminescent element of the electroluminescent display device according to the exemplary embodiment of the present disclosure.

[0019] Figure 6 is a cross-sectional view illustrating a third example of the electroluminescent element of the electroluminescent display device according to the exemplary embodiment of the present disclosure.

[0020] Figure 7 is a cross-sectional view showing a fourth example of the electroluminescent element of the electroluminescent display device according to the exemplary embodiment of the present disclosure.

[0021] Figure 8 is a cross-sectional view showing a fifth example of the electroluminescent element of the electroluminescent display device according to the exemplary embodiment of the present disclosure.

[0022] Fig. 9 is a cross-sectional view showing a sixth example of the electroluminescent element of the electroluminescent display device according to the exemplary embodiment of the present disclosure.

[0023] Fig.10 is a cross-sectional view showing a seventh example of the electroluminescent element of the electroluminescent display device according to the exemplary embodiment of the present disclosure.

[0024] Fig.11 is a cross-sectional view illustrating an eighth example of the electroluminescent element of the electroluminescent display device according to the exemplary embodiment of the present disclosure. DETAILED DESCRIPTION

[0025] The advantages and features of the present disclosure and the methods for achieving the advantages and features will be more clearly understood from the exemplary embodiments described in detail below with reference to the accompanying drawings. However, the present disclosure is not limited to the exemplary embodiments below, but can be implemented in various different forms. The exemplary embodiments are provided only to provide the complete disclosure of the present disclosure and to fully provide the scope of the present disclosure to those skilled in the art to which the present disclosure belongs, and the present disclosure will be limited by the appended claims.

[0026] The shapes, sizes, ratios, angles, quantities, etc. shown in the accompanying drawings for describing the exemplary embodiments of the present disclosure are merely examples, and the present disclosure is not limited thereto. Throughout the specification, similar reference numerals generally represent similar elements. In addition, in the following description, detailed descriptions of known related technologies may be omitted to avoid unnecessarily obscuring the subject matter of the present disclosure.

[0027] Terms such as “including,” “having,” and “consisting of” used herein are generally intended to allow the addition of other components unless the term is used with the term “only.” Any reference to the singular may include the plural unless explicitly stated otherwise.

[0028] Even if not explicitly described, components are interpreted as including the usual margin of error.

[0029] When terms such as “on,” “above,” “below,” and “near” are used to describe the positional relationship between two components, one or more components may be located between the two components unless the terms are used together with the terms “immediately” or “directly.”

[0030] When terms such as "after", "serially", "next", and "before" are used to describe a temporal sequence relationship, the order may not be sequential unless the terms are used with the terms "immediately" or "directly".

[0031] Although the terms first, second, etc. can be used in this article to describe various components, these components should not be limited to these terms. These terms are only used to distinguish one component from another component. Therefore, in the technical concept of the present disclosure, the first component mentioned below in this article can be a second component.

[0032] The “X-axis direction”, “Y-axis direction”, and “Z-axis direction” should not be interpreted only by the geometric relationship of being perpendicular to each other, but may have broader directivities within the range in which the elements of the present disclosure can function functionally.

[0033] The term "at least one" should be understood to include any and all combinations of one or more of the related listed items. For example, the meaning of "at least one of the first, second and third items" means the combination of all items proposed from two or more of the first, second and third items as well as the first, second or third item.

[0034] As those skilled in the art can fully understand, the features of various aspects of the present disclosure can be coupled or combined with each other in part or in whole, and can be technically interoperable and driven with each other in various ways. The aspects of the present disclosure can be performed independently of each other, or can be performed together in a mutually dependent relationship.

[0035] In the following, reference will be made to Figure 1 An electroluminescent display device according to an exemplary embodiment of the present disclosure is described.

[0036] Figure 1 is a block diagram schematically illustrating an electroluminescent display device according to an exemplary embodiment of the present disclosure.

[0037] Reference Figure 1 , the electroluminescent display device according to an exemplary embodiment of the present disclosure includes an image processor 110 , a timing controller 120 , a data driver 130 , a scan driver 140 , and a display panel 150 .

[0038] The image processor 110 outputs a data enable signal DE and a data signal DATA supplied from the outside. In addition to the data enable signal DE, the image processor 110 may also output one or more of a vertical synchronization signal, a horizontal synchronization signal, and a clock signal, however, these signals are omitted for ease of description.

[0039] The timing controller 120 receives a data signal DATA and a driving signal including a data enable signal DE or a vertical synchronization signal, a horizontal synchronization signal, and a clock signal from the image processor 110. The timing controller 120 outputs a gate timing control signal GDC for controlling the operation timing of the scan driver 140 based on the driving signal and a data timing control signal DDC for controlling the operation timing of the data driver 130.

[0040] The data driver 130 samples and latches the data signal DATA supplied from the timing controller 120 in response to the data timing control signal DDC supplied from the timing controller 120 to convert it into a gamma reference voltage and output it. The data driver 130 outputs the data signal DATA through the data lines D1 to Dn. The data driver 130 may be provided in the form of an integrated circuit (IC).

[0041] The scan driver 140 outputs a scan signal while shifting the level of the gate voltage in response to the gate timing control signal GDC supplied from the timing controller 120. The scan driver 140 outputs the scan signal through the scan lines G1 to Gm. The scan driver 140 is provided on the display panel 150 in the form of an integrated circuit (IC) or a gate-in-panel method.

[0042] The display panel 150 displays an image corresponding to the data signal DATA and the scan signal supplied from the data driver 130 and the scan driver 140 .

[0043] Next, refer to Figure 2 and Figure 3, a pixel of an electroluminescent display device according to an exemplary embodiment of the present disclosure will be described.

[0044] Figure 2 yes Figure 1 Schematic circuit configuration diagram of a pixel P of an electroluminescent display device shown in FIG. Figure 3 It is shown Figure 1 An equivalent circuit diagram of an example of a pixel P of an electroluminescent display device shown in FIG.

[0045] Reference Figure 2 In the electroluminescent display device of the present disclosure, each pixel P includes a switching thin film transistor SW, a driving thin film transistor DT, a storage capacitor Cst, a compensation circuit CC, and an organic light emitting diode OLED.

[0046] The switching thin film transistor SW performs a switching operation on the data signal supplied through the first data line D1 in response to the scan signal supplied through the first scan line G1, and the data signal will be stored as the data voltage in the storage capacitor Cst. The driving thin film transistor DT enables a driving current to flow between the first power line EVDD and the second power line EVSS according to the data voltage stored in the storage capacitor Cst. The electroluminescent element OLED operates to emit light according to the driving current provided by the driving thin film transistor DT.

[0047] The compensation circuit CC is a circuit added in the sub-pixel to compensate for the threshold voltage of the driving thin film transistor DT. The compensation circuit CC may include one or more thin film transistors. The compensation circuit CC may be configured in various ways according to the compensation method.

[0048] Reference Figure 3 , Figure 2 The compensation circuit CC shown in FIG. 1 includes a sensing thin film transistor ST and a sensing line VREF. The sensing thin film transistor ST is connected between the drain of the driving thin film transistor DT and the anode of the electroluminescent element OLED (hereinafter referred to as a sensing node). The sensing thin film transistor ST operates to supply an initialization voltage (or a sensing voltage) transmitted through the sensing line VREF to the sensing node, or operates to sense a voltage or current of the sensing node.

[0049] The switching thin film transistor SW includes a source connected to the first data line D1 and a drain connected to the gate of the driving thin film transistor DT. The driving thin film transistor DT includes a source connected to the first power line EVDD and a drain connected to the anode of the electroluminescent element OLED.

[0050] The storage capacitor Cst includes a first electrode E1 connected to the anode electrode of the electroluminescent element OLED and a second electrode E2 connected to the gate electrode of the driving thin film transistor DT.

[0051] The electroluminescent element OLED includes an anode connected to the drain electrode of the driving thin film transistor DT and a cathode connected to the second source line EVSS.

[0052] The sensing thin film transistor ST includes a source connected to the sensing line VREF and a drain connected to a sensing node to which the anode of the electroluminescent element OLED is connected.

[0053] According to the compensation algorithm (or the configuration of the compensation circuit), the operation timing of the sensing thin film transistor ST may be similar, the same, or different from the operation timing of the switching thin film transistor SW. For example, the sensing thin film transistor ST may have a gate connected to the 1a scan line G1a, and the switching thin film transistor SW may have a gate connected to the 1b scan line G1b. As another example, the 1a scan line G1a connected to the gate of the sensing thin film transistor ST and the 1b scan line G1b connected to the gate of the switching thin film transistor SW may be connected to be shared.

[0054] The sensing line VREF may be connected to the data driver. In this case, the data driver may sense the sensing node of the pixel and generate a sensing result in real time, during a non-display period of the image, or during an N-frame period (where N is an integer greater than 1). At the same time, the switching thin film transistor SW and the sensing thin film transistor ST may be turned on at the same time. In this case, based on the time division method of the data driver, the sensing operation through the sensing line VREF and the data output operation for outputting the data signal are independent (or separated) from each other.

[0055] In addition, the compensation object according to the sensing result may be a digital data signal, an analog data signal, a gamma signal, etc. The compensation circuit that generates a compensation signal (or compensation voltage) based on the sensing result may be implemented inside the data driver or inside the timing controller, or implemented as a separate circuit.

[0056] In addition, Figure 3 In the example, although a pixel with a 3T (transistor) 1C (capacitor) structure including a switching thin film transistor SW, a driving thin film transistor DT, a storage capacitor Cst, an electroluminescent element OLED and a sensing thin film transistor ST has been described as an example, when a compensation circuit CC is added, each sub-pixel may be composed of 3T2C, 4T2C, 5T1C, 6T2C, etc.

[0057] In the following, reference will be made to Figures 4 to 11 An electroluminescent element of an electroluminescent display device according to an exemplary embodiment of the present disclosure is described.

[0058] Figure 4is a cross-sectional view showing a first example of an electroluminescent element of an electroluminescent display device according to an exemplary embodiment of the present disclosure.

[0059] Reference Figure 4 , the electroluminescent element according to the first example of the exemplary embodiment of the present disclosure includes a first light emitting element LE1 and a second light emitting element LE2.

[0060] The first light emitting element LE1 includes: a first transparent substrate SUB1; a first anode AN1, located on one surface of the first transparent substrate SUB1; a first light emitting layer OL1, provided with a first light emitter R and a second light emitter B, the first light emitter R and the second light emitter B are arranged adjacent to each other and located on the first anode AN1; and a first cathode CA1, arranged on the first light emitting layer OL1. The first light emitter R emits red light, and the second light emitter B emits blue light.

[0061] The second light emitting element LE2 includes: a second transparent substrate SUB2; a second anode AN2 located on one surface of the second transparent substrate SUB2; a second light emitting layer OL2 including a third light emitter G disposed on the second anode AN2; and a second cathode CA2 disposed on the second light emitting layer OL2. The third light emitter G emits green light.

[0062] After the first cathode CA1 and the second cathode CA2 are disposed to face each other, the first light emitting element LE1 and the second light emitting element LE2 are bonded by a transparent conductive adhesive (not shown).

[0063] The first transparent substrate SUB1 and the second transparent substrate SUB2 may be flexible substrates or glass substrates, and the flexible substrate may be a resin substrate such as flexible polyimide.

[0064] The first anode AN1 may be formed of any one selected from Ni, Cr, Al, Ag, a three-layer structure of ITO (Indium Tin Oxide) / Ag / ITO, and a two-layer structure of Al / ITO. The first anode AN1 serves as a reflective electrode.

[0065] The second anode AN2 may be formed of any one selected from a transparent conductive polymer material such as indium tin oxide (ITO), indium zinc oxide (IZO), carbon nanotube (CNT), and PEDOT:PSS. The second anode AN2 serves as a light-transmitting electrode.

[0066] The first light emitter R may include a first hole injection layer, a first hole transport layer, a first light emitting layer (e.g., a red light emitting layer), and a first electron transport layer. The second light emitter B may include a second hole injection layer, a second hole transport layer, a second light emitting layer (e.g., a blue light emitting layer), and a second electron transport layer. The third light emitter G may include a third hole injection layer, a third hole transport layer, a third light emitting layer (e.g., a green light emitting layer), and a third electron transport layer.

[0067] The first cathode CA1 and the second cathode CA2 may be formed of any one selected from a two-layer structure of Ca / Ag, a Li:Al alloy, and a Mg:Ag alloy. The first cathode CA1 and the second cathode CA2 serve as semi-transparent electrodes that semi-transmit light. The thickness of the second cathode CA2 is preferably formed thinner than that of the first cathode CA1 to reduce the loss of the amount of light emitted from the first light emitting layer OL1.

[0068] The transparent conductive adhesive (not shown) for bonding the first light emitting element LE1 and the second light emitting element LE2 may be formed of a transparent adhesive monomer and a conductive polymer material or a combination of ITO nanopowder. The transparent adhesive monomer may be selected from any one of acrylic monomers, epoxy monomers, ether monomers and combinations thereof. In addition, the conductive polymer can be selected from any one of polyacetylene, polypyrrole, polythiophene, poly(3-alkylthiophene), polyphenylene sulfide, polyparaphenylene sulfide, polyphenylene vinylene, polyparaphenylene vinylene, polythienylene vinylene, polyphenylene, polyparaphenylene, polyazulene, polyfuran, polyaniline, polyselenophene, polytellurophene and combinations thereof.

[0069] According to the electroluminescent element based on the first example of the present disclosure, the red light emitted from the first light emitter R of the first light emitting element LE1 and the blue light emitted from the second light emitter B are emitted to the outside through the second anode AN2 and the second transparent substrate SUB2 after being incident on the third light emitter G through the first cathode CA1 and the second cathode CA2. Depending on whether the third light emitter G of the second light emitting element LE2 is working, among the light emitted from the first light emitter R and the light emitted from the second light emitter B, only red light or blue light may be emitted, or a mixture of red light and green light or a mixture of blue light and green light may be emitted. In addition, depending on whether the first light emitter R and the second light emitter B are working, among the light emitted from the third light emitter G, only green light may be emitted, or a mixture of green light and red light or a mixture of green light and blue light may be emitted. Therefore, since the light emitted from the first light emitting element LE1 is combined with the light emitted from the second light emitting element LE2 and emitted to the outside, it is possible to ensure the effect of obtaining light with high brightness and high resolution.

[0070] Figure 5 is a cross-sectional view illustrating a second example of the electroluminescent element of the electroluminescent display device according to the exemplary embodiment of the present disclosure.

[0071] Reference Figure 5 , the electroluminescent element according to the second example of the exemplary embodiment of the present disclosure includes a first light emitting element LE1 and a second light emitting element LE2.

[0072] The first light emitting element LE1 includes: a first transparent substrate SUB1; a first anode AN1, located on one surface of the first transparent substrate SUB1; a first light emitting layer OL1, provided with a first light emitter R and a second light emitter G, the first light emitter R and the second light emitter G are arranged adjacent to each other and located on the first anode AN1; and a first cathode CA1, arranged on the first light emitting layer OL1. The first light emitter R emits red light, and the second light emitter G emits green light.

[0073] The second light emitting element LE2 includes: a second transparent substrate SUB2; a second anode AN2 located on one surface of the second transparent substrate SUB2; a second light emitting layer OL2 including a third light emitter B disposed on the second anode AN2; and a second cathode CA2 disposed on the second light emitting layer OL2. The third light emitter B emits blue light.

[0074] After the first cathode CA1 and the second cathode CA2 are disposed to face each other, the first light emitting element LE1 and the second light emitting element LE2 are bonded by a transparent conductive adhesive (not shown).

[0075] The first transparent substrate SUB1 and the second transparent substrate SUB2 may be flexible substrates or glass substrates, and the flexible substrate may be a resin substrate such as flexible polyimide.

[0076] The first anode AN1 may be formed of any one selected from Ni, Cr, Al, Ag, a three-layer structure of ITO (Indium Tin Oxide) / Ag / ITO, and a two-layer structure of Ag / ITO. The first anode AN1 serves as a reflective electrode.

[0077] The second anode AN2 may be formed of any one selected from a transparent conductive polymer material such as indium tin oxide (ITO), indium zinc oxide (IZO), carbon nanotube (CNT), and PEDOT:PSS. The second anode AN2 serves as a light-transmitting electrode.

[0078] The first light emitter R may include a first hole injection layer, a first hole transport layer, a first light emitting layer (e.g., a red light emitting layer), and a first electron transport layer. The second light emitter G may include a second hole injection layer, a second hole transport layer, a second light emitting layer (e.g., a green light emitting layer), and a second electron transport layer. The third light emitter B may include a third hole injection layer, a third hole transport layer, a third light emitting layer (e.g., a blue light emitting layer), and a third electron transport layer.

[0079] The first cathode CA1 and the second cathode CA2 may be formed of any one selected from a two-layer structure of Ca / Ag, a Li:Al alloy, and a Mg:Ag alloy. The first cathode CA1 and the second cathode CA2 serve as semi-transparent electrodes that semi-transmit light. The thickness of the second cathode CA2 is preferably formed thinner than that of the first cathode CA1 to reduce the loss of the amount of light emitted from the first light emitting layer OL1.

[0080] The transparent conductive adhesive (not shown) used to bond the first light emitting element LE1 and the second light emitting element LE2 can be formed by a transparent adhesive monomer, and a conductive polymer material or a combination of ITO nanopowder. The transparent adhesive monomer can be selected from any one of acrylic monomers, epoxy monomers, ether monomers, and combinations thereof. In addition, the conductive polymer can be selected from any one of polyacetylene, polypyrrole, polythiophene, poly(3-alkylthiophene), polyphenylene sulfide, poly-p-phenylene sulfide, polyphenylene vinylene, poly-p-phenylene vinylene, poly-thiophene vinylene, polyphenylene, poly-p-phenylene, polyazulene, polyfuran, polyaniline, polyselenophene, polytellurophene, and combinations thereof.

[0081] According to the electroluminescent element according to the second example of the present disclosure, the red light emitted from the first light emitter R of the first light emitting element LE1 and the green light emitted from the second light emitter G are emitted to the outside through the second anode AN2 and the second transparent substrate SUB2 after being incident on the third light emitter B through the first cathode CA1 and the second cathode CA2. Depending on whether the third light emitter B of the second light emitting element LE2 is working, among the light emitted from the first light emitter R and the light emitted from the second light emitter G, only red light or green light may be emitted, or a mixture of red light and blue light or a mixture of green light and blue light may be emitted. In addition, depending on whether the first light emitter R and the second light emitter G are working, among the light emitted from the third light emitter B, only blue light may be emitted, or a mixture of blue light and red light or a mixture of blue light and green light may be emitted. Therefore, since the light emitted from the first light emitting element LE1 is combined with the light emitted from the second light emitting element LE2 and emitted to the outside, it is possible to ensure the effect of obtaining light with high brightness and high resolution.

[0082] Figure 6 is a cross-sectional view illustrating a third example of the electroluminescent element of the electroluminescent display device according to the exemplary embodiment of the present disclosure.

[0083] Reference Figure 6 , the electroluminescent element of the third example of the exemplary embodiments of the present disclosure includes a first light emitting element LE1 and a second light emitting element LE2.

[0084] The first light emitting element LE1 includes: a first transparent substrate SUB1; a first anode AN1, located on one surface of the first transparent substrate SUB1; a first light emitting layer OL1, provided with a first light emitter G and a second light emitter B, the first light emitter G and the second light emitter B are arranged adjacent to each other and located on the first anode AN1; and a first cathode CA1, arranged on the first light emitting layer OL1. The first light emitter G emits green light, and the second light emitter B emits blue light.

[0085] The second light emitting element LE2 includes: a second transparent substrate SUB2; a second anode AN2 located on one surface of the second transparent substrate SUB2; a second light emitting layer OL2 disposed on the second anode AN2 and including a third light emitter R; and a second cathode CA2 disposed on the second light emitting layer OL2. The third light emitter R emits red light.

[0086] After the first cathode CA1 and the second cathode CA2 are disposed to face each other, the first light emitting element LE1 and the second light emitting element LE2 are bonded by a transparent conductive adhesive (not shown).

[0087] The first transparent substrate SUB1 and the second transparent substrate SUB2 may be flexible substrates or glass substrates, and the flexible substrate may be a resin substrate such as flexible polyimide.

[0088] The first anode AN1 may be formed of any one selected from Ni, Cr, Al, Ag, a three-layer structure of ITO (Indium Tin Oxide) / Ag / ITO, and a two-layer structure of Al / ITO. The first anode AN1 serves as a reflective electrode.

[0089] The second anode AN2 may be formed of any one selected from a transparent conductive polymer material such as indium tin oxide (ITO), indium zinc oxide (IZO), carbon nanotube (CNT), and PEDOT:PSS. The second anode AN2 serves as a light-transmitting electrode.

[0090] The first light emitter G may include a first hole injection layer, a first hole transport layer, a first light emitting layer (e.g., a green light emitting layer), and a first electron transport layer. The second light emitter B may include a second hole injection layer, a second hole transport layer, a second light emitting layer (e.g., a blue light emitting layer), and a second electron transport layer. The third light emitter R may include a third hole injection layer, a third hole transport layer, a third light emitting layer (e.g., a red light emitting layer), and a third electron transport layer.

[0091] The first cathode CA1 and the second cathode CA2 may be formed of any one selected from a two-layer structure of Ca / Ag, a Li:Al alloy, and a Mg:Ag alloy. The first cathode CA1 and the second cathode CA2 serve as semi-transparent electrodes that semi-transmit light. The thickness of the second cathode CA2 is preferably formed thinner than that of the first cathode CA1 to reduce the loss of the amount of light emitted from the first light emitting layer OL1.

[0092] The transparent conductive adhesive (not shown) used to bond the first light emitting element LE1 and the second light emitting element LE2 can be formed by a transparent adhesive monomer, and a conductive polymer material or a combination of ITO nanopowder. The transparent adhesive monomer can be selected from any one of acrylic monomers, epoxy monomers, ether monomers, and combinations thereof. In addition, the conductive polymer can be selected from any one of polyacetylene, polypyrrole, polythiophene, poly(3-alkylthiophene), polyphenylene sulfide, poly-p-phenylene sulfide, polyphenylene vinylene, poly-p-phenylene vinylene, poly-thiophene vinylene, polyphenylene, poly-p-phenylene, polyazulene, polyfuran, polyaniline, polyselenophene, polytellurophene, and combinations thereof.

[0093] According to the electroluminescent element according to the third example of the present disclosure, the green light emitted from the first light emitter G of the first light emitting element LE1 and the blue light emitted from the second light emitter B are emitted to the outside through the second anode AN2 and the second transparent substrate SUB2 after being incident on the third light emitter R through the first cathode CA1 and the second cathode CA2. Depending on whether the third light emitter R of the second light emitting element LE2 is working, among the light emitted from the first light emitter G and the light emitted from the second light emitter B, only green light or blue light may be emitted, or light mixed with green light and red light or light mixed with blue light and red light may be emitted. In addition, depending on whether the first light emitter G and the second light emitter B are working, among the light emitted from the third light emitter R, only red light may be emitted, or light mixed with green light and red light or light mixed with blue light and red light may be emitted. Therefore, since the light emitted from the first light emitting element LE1 is combined with the light emitted from the second light emitting element LE2 and emitted to the outside, it is possible to ensure the effect of obtaining light with high brightness and high resolution.

[0094] Figure 7 is a cross-sectional view showing a fourth example of the electroluminescent element of the electroluminescent display device according to the exemplary embodiment of the present disclosure.

[0095] Reference Figure 7 , the electroluminescent element according to the fourth example of the exemplary embodiments of the present disclosure includes a first light emitting element LE1 and a second light emitting device LE2.

[0096] The first light emitting element LE1 includes: a first transparent substrate SUB1; a first anode AN1, located on one surface of the first transparent substrate SUB1; a first light emitting layer OL1, provided with a first light emitter R and a second light emitter B, the first light emitter R and the second light emitter B are arranged adjacent to each other and located on the first anode AN1; and a first cathode CA1, arranged on the first light emitting layer OL1. The first light emitter R emits red light, and the second light emitter B emits blue light.

[0097] The second light emitting element LE2 includes: a second transparent substrate SUB2; a second anode AN2, which is located on one surface of the second transparent substrate SUB2; a second light emitting layer OL2, including a third light emitter B and a fourth light emitter G, which are arranged on the second anode AN2 to face each other; and a second cathode CA2, which is arranged on the second light emitting layer OL2. The third light emitter B is arranged to overlap with the first light emitter R, and the fourth light emitter G is arranged to overlap with the second light emitter B. The third light emitter B emits blue light, and the fourth light emitter G emits green light. After the first cathode CA1 and the second cathode CA2 are arranged to face each other, the first light emitting element LE1 and the second light emitting element LE2 are bonded by a transparent conductive adhesive (not shown).

[0098] The first transparent substrate SUB1 and the second transparent substrate SUB2 may be flexible substrates or glass substrates, and the flexible substrate may be a resin substrate such as flexible polyimide.

[0099] The first anode AN1 may be formed of any one selected from Ni, Cr, Al, Ag, a three-layer structure of ITO (Indium Tin Oxide) / Ag / ITO, and a two-layer structure of Al / ITO. The first anode AN1 serves as a reflective electrode.

[0100] The second anode AN2 may be formed of any one selected from a transparent conductive polymer material such as indium tin oxide (ITO), indium zinc oxide (IZO), carbon nanotube (CNT), and PEDOT:PSS. The second anode AN2 serves as a light-transmitting electrode.

[0101] The first light emitter R may include a first hole injection layer, a first hole transport layer, a first light emitting layer (e.g., a red light emitting layer), and a first electron transport layer. The second light emitter B may include a second hole injection layer, a second hole transport layer, a second light emitting layer (e.g., a blue light emitting layer), and a second electron transport layer. The third light emitter B may include a third hole injection layer, a third hole transport layer, a third light emitting layer (e.g., a green light emitting layer), and a third electron transport layer. The fourth light emitter G may include a fourth hole injection layer, a fourth hole transport layer, a fourth light emitting layer (e.g., a green light emitting layer), and a fourth electron transport layer.

[0102] The first cathode CA1 and the second cathode CA2 may be formed of any one selected from a two-layer structure of Ca / Ag, a Li:Al alloy, and a Mg:Ag alloy. The first cathode CA1 and the second cathode CA2 serve as semi-transparent electrodes that semi-transmit light. The thickness of the second cathode CA2 is preferably formed thinner than that of the first cathode CA1 to reduce the loss of the amount of light emitted from the first light emitting layer OL1.

[0103] The transparent conductive adhesive (not shown) used to bond the first light emitting element LE1 and the second light emitting element LE2 can be formed by a transparent adhesive monomer, and a conductive polymer material or a combination of ITO nanopowder. The transparent adhesive monomer can be selected from any one of acrylic monomers, epoxy monomers, ether monomers, and combinations thereof. In addition, the conductive polymer can be selected from any one of polyacetylene, polypyrrole, polythiophene, poly(3-alkylthiophene), polyphenylene sulfide, poly-p-phenylene sulfide, polyphenylene vinylene, poly-p-phenylene vinylene, poly-thiophene vinylene, polyphenylene, poly-p-phenylene, polyazulene, polyfuran, polyaniline, polyselenophene, polytellurophene, and combinations thereof.

[0104] According to the electroluminescent element according to the fourth example of the present disclosure, the red light emitted from the first light emitter R of the first light emitting element LE1 is emitted to the outside through the second anode AN2 and the second transparent substrate SUB2 after being incident on the third light emitter B through the first cathode CA1 and the second cathode CA2. The blue light emitted from the third light emitter B is emitted to the outside through the second anode AN2 and the second transparent substrate SUB2. Depending on whether the fourth light emitter G is working, among the light emitted from the first light emitter R and the light emitted from the third light emitter B, red light, blue light, or a mixture of red light and green light or a mixture of blue light and green light may be emitted.

[0105] In addition, after being incident on the fourth light emitter G through the first cathode CA1 and the second cathode CA2, the blue light emitted from the second light emitter B of the first light emitting element LE1 is emitted to the outside through the second anode AN2 and the second transparent substrate SUB2. The green light emitted from the fourth light emitter G is emitted to the outside through the second anode AN2 and the second transparent substrate SUB2. Depending on whether the first light emitter R is working, among the light emitted from the second light emitter B and the light emitted from the fourth light emitter G, blue light, green light, or a mixture of blue light and red light or a mixture of green light and red light may be emitted.

[0106] Therefore, since the light emitted from the first light emitting element LE1 is combined with the light emitted from the second light emitting element LE2 and emitted to the outside, it is possible to ensure that the effect of obtaining light with high brightness and high resolution is obtained.

[0107] Figure 8 is a cross-sectional view showing a fifth example of the electroluminescent element of the electroluminescent display device according to the exemplary embodiment of the present disclosure.

[0108] Reference Figure 8 , the electroluminescent element according to the fifth example of the exemplary embodiments of the present disclosure includes a first light emitting element LE1 and a second light emitting element LE2.

[0109] The first light emitting element LE1 includes: a first transparent substrate SUB1; a first anode AN1, located on one surface of the first transparent substrate SUB1; a first light emitting layer OL1, provided with a first light emitter R and a second light emitter G, the first light emitter R and the second light emitter G are arranged adjacent to each other and located on the first anode AN1; and a first cathode CA1, arranged on the first light emitting layer OL1. The first light emitter R emits red light, and the second light emitter G emits green light.

[0110] The second light emitting element LE2 includes: a second transparent substrate SUB2; a second anode AN2, which is located on one surface of the second transparent substrate SUB2; a second light emitting layer OL2, including a third light emitter G and a fourth light emitter B, which are arranged adjacent to each other and located on the first anode AN1; and a second cathode CA2, which is arranged on the second light emitting layer OL2. The third light emitter G is arranged to overlap with the first light emitter R, and the fourth light emitter B is arranged to overlap with the second light emitter G. The third light emitter G emits green light, and the fourth light emitter B emits blue light. After the first cathode CA1 and the second cathode CA2 are arranged to face each other, the first light emitting element LE1 and the second light emitting element LE2 are bonded by a transparent conductive adhesive (not shown).

[0111] The first transparent substrate SUB1 and the second transparent substrate SUB2 may be flexible substrates or glass substrates, and the flexible substrate may be a resin substrate such as flexible polyimide.

[0112] The first anode AN1 may be formed of any one selected from Ni, Cr, Al, Ag, a three-layer structure of ITO (Indium Tin Oxide) / Ag / ITO, and a two-layer structure of Al / ITO. The first anode AN1 serves as a reflective electrode.

[0113] The second anode AN2 may be formed of any one selected from a transparent conductive polymer material such as indium tin oxide (ITO), indium zinc oxide (IZO), carbon nanotube (CNT), and PEDOT:PSS. The second anode AN2 serves as a light-transmitting electrode.

[0114] The first light emitter R may include a first hole injection layer, a first hole transport layer, a first light emitting layer (e.g., a red light emitting layer), and a first electron transport layer. The second light emitter G may include a second hole injection layer, a second hole transport layer, a second light emitting layer (e.g., a green light emitting layer), and a second electron transport layer. The third light emitter G may include a third hole injection layer, a third hole transport layer, a third light emitting layer (e.g., a green light emitting layer), and a third electron transport layer. The fourth light emitter B may include a fourth hole injection layer, a fourth hole transport layer, a fourth light emitting layer (e.g., a blue light emitting layer), and a fourth electron transport layer.

[0115] The first cathode CA1 and the second cathode CA2 may be formed of any one selected from a two-layer structure of Ca / Ag, a Li:Al alloy, and a Mg:Ag alloy. The first cathode CA1 and the second cathode CA2 serve as semi-transparent electrodes that semi-transmit light. The thickness of the second cathode CA2 is preferably formed thinner than that of the first cathode CA1 to reduce the loss of the amount of light emitted from the first light emitting layer OL1.

[0116] The transparent conductive adhesive (not shown) used to bond the first light emitting element LE1 and the second light emitting element LE2 can be formed by a transparent adhesive monomer, and a conductive polymer material or a combination of ITO nanopowder. The transparent adhesive monomer can be selected from any one of acrylic monomers, epoxy monomers, ether monomers, and combinations thereof. In addition, the conductive polymer can be selected from any one of polyacetylene, polypyrrole, polythiophene, poly(3-alkylthiophene), polyphenylene sulfide, poly-p-phenylene sulfide, polyphenylene vinylene, poly-p-phenylene vinylene, poly-thiophene vinylene, polyphenylene, poly-p-phenylene, polyazulene, polyfuran, polyaniline, polyselenophene, polytellurophene, and combinations thereof.

[0117] According to the electroluminescent element according to the fifth example of the present disclosure, the red light emitted from the first light emitter R of the first light emitting element LE1 is emitted to the outside through the second anode AN2 and the second transparent substrate SUB2 after being incident on the third light emitter G through the first cathode CA1 and the second cathode CA2. The green light emitted from the third light emitter G is emitted to the outside through the second anode AN2 and the second transparent substrate SUB2. Depending on whether the fourth light emitter B is working, among the light emitted from the first light emitter R and the light emitted from the second light emitter G, red light, green light, or a mixture of red light and blue light or a mixture of green light and blue light may be emitted.

[0118] In addition, the green light emitted from the second light emitter G of the second light emitting element LE1 is incident on the fourth light emitter B through the first cathode CA1 and the second cathode CA2, and then emitted to the outside through the second anode AN2 and the second transparent substrate SUB2. The blue light emitted from the fourth light emitter B is emitted to the outside through the second anode AN2 and the second transparent substrate SUB2. Depending on whether the first light emitter R is working, among the light emitted from the second light emitter G and the blue light emitted from the fourth light emitter B, green light, blue light, or a mixture of green and red light or a mixture of blue and red light may be emitted.

[0119] Therefore, since the light emitted from the first light emitting element LE1 is combined with the light emitted from the second light emitting element LE2 and emitted to the outside, it is possible to ensure that the effect of obtaining light with high brightness and high resolution is obtained.

[0120] Fig. 9 is a cross-sectional view showing a sixth example of the electroluminescent element of the electroluminescent display device according to the exemplary embodiment of the present disclosure.

[0121] Reference Fig. 9 , the electroluminescent element according to the sixth example of the exemplary embodiments of the present disclosure includes a first light emitting element LE1 and a second light emitting element LE2.

[0122] The first light emitting element LE1 includes: a first transparent substrate SUB1; a first anode AN1, which is located on one surface of the first transparent substrate SUB1; a first light emitting layer OL1, including a first light emitter Y, which is disposed on the first anode AN1; a first cathode CA1, which is disposed on the first light emitting layer OL1; and a color filter layer CL, which is provided with a first color filter CF1 and a second color filter CF2, which are disposed adjacent to each other and located on the first cathode CA1. The first light emitter Y emits yellow light. The first color filter CF1 is a red color filter that displays red, and the second color filter CF2 is a green color filter that displays green.

[0123] The second light emitting element LE2 includes: a second transparent substrate SUB2; a second anode AN2 located on one surface of the second transparent substrate SUB2; a second light emitting layer OL2 including a second light emitter B disposed on the second anode AN2; and a second cathode CA2 disposed on the second light emitting layer OL2. The second light emitter B emits blue light.

[0124] After the color filter layer CL and the second cathode electrode CA2 are disposed to face each other, the first light emitting element LE1 and the second light emitting element LE2 are bonded by a transparent conductive adhesive (not shown).

[0125] The first transparent substrate SUB1 and the second transparent substrate SUB2 may be flexible substrates or glass substrates, and the flexible substrate may be a resin substrate such as flexible polyimide.

[0126] The first anode AN1 may be formed of any one selected from Ni, Cr, Al, Ag, a three-layer structure of ITO (Indium Tin Oxide) / Ag / ITO, and a two-layer structure of Al / ITO. The first anode AN1 serves as a reflective electrode.

[0127] The second anode AN2 may be formed of any one selected from a transparent conductive polymer material such as indium tin oxide (ITO), indium zinc oxide (IZO), carbon nanotube (CNT), and PEDOT:PSS. The second anode AN2 serves as a light-transmitting electrode.

[0128] The first light emitter Y may include a first hole injection layer, a first hole transport layer, a first light emitting layer (e.g., a yellow light emitting layer), and a first electron transport layer. The second light emitter B may include a second hole injection layer, a second hole transport layer, a second light emitting layer (e.g., a blue light emitting layer), and a second electron transport layer.

[0129] The first cathode CA1 and the second cathode CA2 may be formed of any one selected from a two-layer structure of Ca / Ag, a Li:Al alloy, and a Mg:Ag alloy. The first cathode CA1 and the second cathode CA2 serve as semi-transparent electrodes that semi-transmit light. The thickness of the second cathode CA2 is preferably formed thinner than that of the first cathode CA1 to reduce the loss of the amount of light emitted from the first light emitting layer OL1.

[0130] The transparent conductive adhesive (not shown) used to bond the first light emitting element LE1 and the second light emitting element LE2 can be formed by a transparent adhesive monomer, and a conductive polymer material or a combination of ITO nanopowder. The transparent adhesive monomer can be selected from any one of acrylic monomers, epoxy monomers, ether monomers, and combinations thereof. In addition, the conductive polymer can be selected from any one of polyacetylene, polypyrrole, polythiophene, poly(3-alkylthiophene), polyphenylene sulfide, poly-p-phenylene sulfide, polyphenylene vinylene, poly-p-phenylene vinylene, poly-thiophene vinylene, polyphenylene, poly-p-phenylene, polyazulene, polyfuran, polyaniline, polyselenophene, polytellurophene, and combinations thereof.

[0131] According to the electroluminescent element of the sixth example according to the present disclosure, the yellow light emitted from the first light emitter Y of the first light emitting element LE1 is incident on the second light emitter B through the second cathode CA2 after passing through the first color filter (i.e., red color filter), and then emitted to the outside through the second anode AN2 and the second transparent substrate SUB2. The yellow light emitted from the first light emitter Y is converted into red light after passing through the first color filter CF1, and then converted into green light after passing through the second color filter CF2. Therefore, since the light emitted from the first light emitting element LE1 is combined with the light emitted from the second light emitting element LE2 and emitted to the outside, it is possible to ensure that the effect of obtaining light with high brightness and high resolution is obtained.

[0132] Fig.10 is a cross-sectional view showing a seventh example of the electroluminescent element of the electroluminescent display device according to the exemplary embodiment of the present disclosure.

[0133] Reference Fig.10 , the electroluminescent element according to the seventh example of the exemplary embodiments of the present disclosure includes a first light emitting element LE1 and a second light emitting element LE2.

[0134] The first light emitting element LE1 includes: a first transparent substrate SUB1; a first anode AN1, which is located on one surface of the first transparent substrate SUB1; a first light emitting layer OL1, including a first light emitter C, which is disposed on the first anode AN1; a first cathode CA1, which is disposed on the first light emitting layer OL1; and a color filter layer CL, which is provided with a first color filter CF1 and a second color filter CF2, which are disposed adjacent to each other and located on the first cathode CA1. The first light emitter C emits cyan light. The first color filter CF1 is a blue color filter that displays blue, and the second color filter CF2 is a green color filter that displays green.

[0135] The second light emitting element LE2 includes: a second transparent substrate SUB2; a second anode AN2 located on one surface of the second transparent substrate SUB2; a second light emitting layer OL2 including a second light emitter R disposed on the second anode AN2; and a second cathode CA2 disposed on the second light emitting layer OL2. The second light emitter R emits red light.

[0136] After the color filter layer CL and the second cathode electrode CA2 are disposed to face each other, the first light emitting element LE1 and the second light emitting element LE2 are bonded by a transparent conductive adhesive (not shown).

[0137] The first transparent substrate SUB1 and the second transparent substrate SUB2 may be flexible substrates or glass substrates, and the flexible substrate may be a resin substrate such as flexible polyimide.

[0138] The first anode AN1 may be formed of any one selected from Ni, Cr, Al, Ag, a three-layer structure of ITO (Indium Tin Oxide) / Ag / ITO, and a two-layer structure of Al / ITO. The first anode AN1 serves as a reflective electrode.

[0139] The second anode AN2 may be formed of any one selected from a transparent conductive polymer material such as indium tin oxide (ITO), indium zinc oxide (IZO), carbon nanotube (CNT), and PEDOT:PSS. The second anode AN2 serves as a light-transmitting electrode.

[0140] The first light emitter C may include a first hole injection layer, a first hole transport layer, a first light emitting layer (e.g., a cyan light emitting layer), and a first electron transport layer. The second light emitter R may include a second hole injection layer, a second hole transport layer, a second light emitting layer (e.g., a red light emitting layer), and a second electron transport layer.

[0141] The first cathode CA1 and the second cathode CA2 may be formed of any one selected from a two-layer structure of Ca / Ag, a Li:Al alloy, and a Mg:Ag alloy. The first cathode CA1 and the second cathode CA2 serve as semi-transparent electrodes that semi-transmit light. The thickness of the second cathode CA2 is preferably formed thinner than that of the first cathode CA1 to reduce the loss of the amount of light emitted from the first light emitting layer OL1.

[0142] The transparent conductive adhesive (not shown) used to bond the first light emitting element LE1 and the second light emitting element LE2 can be formed by a transparent adhesive monomer, and a conductive polymer material or a combination of ITO nanopowder. The transparent adhesive monomer can be selected from any one of acrylic monomers, epoxy monomers, ether monomers, and combinations thereof. In addition, the conductive polymer can be selected from any one of polyacetylene, polypyrrole, polythiophene, poly(3-alkylthiophene), polyphenylene sulfide, poly-p-phenylene sulfide, polyphenylene vinylene, poly-p-phenylene vinylene, poly-thiophene vinylene, polyphenylene, poly-p-phenylene, polyazulene, polyfuran, polyaniline, polyselenophene, polytellurophene, and combinations thereof.

[0143] According to the electroluminescent element of the seventh example according to the present disclosure, the cyan light emitted from the first light emitter C of the first light emitting element LE1 is incident on the second light emitter R through the second cathode CA2 after passing through the first color filter (i.e., blue color filter), and then is emitted to the outside through the second anode AN2 and the second transparent substrate SUB2. The cyan light emitted from the first light emitter C is converted into blue light after passing through the first color filter CF1, and then converted into green light after passing through the second color filter CF2. Therefore, since the light emitted from the first light emitting element LE1 is combined with the light emitted from the second light emitting element LE2 and emitted to the outside, it is possible to ensure that the effect of obtaining light with high brightness and high resolution is obtained.

[0144] Fig.11 is a cross-sectional view illustrating an eighth example of the electroluminescent element of the electroluminescent display device according to the exemplary embodiment of the present disclosure.

[0145] Reference Fig.11 , the electroluminescent element according to the eighth example of the exemplary embodiments of the present disclosure includes a first light emitting element LE1 and a second light emitting element LE2.

[0146] The first light emitting element LE1 includes: a first transparent substrate SUB1; a first anode AN1, which is located on one surface of the first transparent substrate SUB1; a first light emitting layer OL1, including a first light emitter M, which is disposed on the first anode AN1; a first cathode CA1, which is disposed on the first light emitting layer OL1; and a color filter layer CL, which is provided with a first color filter CF1 and a second color filter CF2, which are disposed adjacent to each other and located on the first cathode CA1. The first light emitter M emits magenta. The first color filter CF1 is a red color filter that displays red, and the second color filter CF2 is a blue color filter that displays blue.

[0147] The second light emitting element LE2 includes: a second transparent substrate SUB2; a second anode AN2 located on one surface of the second transparent substrate SUB2; a second light emitting layer OL2 including a second light emitter G disposed on the second anode AN2; and a second cathode CA2 disposed on the second light emitting layer OL2. The second light emitter G emits green light.

[0148] After the color filter layer CL and the second cathode electrode CA2 are disposed to face each other, the first light emitting element LE1 and the second light emitting element LE2 are bonded by a transparent conductive adhesive (not shown).

[0149] The first transparent substrate SUB1 and the second transparent substrate SUB2 may be flexible substrates or glass substrates, and the flexible substrate may be a resin substrate such as flexible polyimide.

[0150] The first anode AN1 may be formed of any one selected from Ni, Cr, Al, Ag, a three-layer structure of ITO (Indium Tin Oxide) / Ag / ITO, and a two-layer structure of Al / ITO. The first anode AN1 serves as a reflective electrode.

[0151] The second anode AN2 may be formed of any one selected from a transparent conductive polymer material such as indium tin oxide (ITO), indium zinc oxide (IZO), carbon nanotube (CNT), and PEDOT:PSS. The second anode AN2 serves as a light-transmitting electrode.

[0152] The first light emitter M may include a first hole injection layer, a first hole transport layer, a first light emitting layer (e.g., a magenta light emitting layer), and a first electron transport layer. The second light emitter G may include a second hole injection layer, a second hole transport layer, a second light emitting layer (e.g., a green light emitting layer), and a second electron transport layer.

[0153] The first cathode CA1 and the second cathode CA2 may be formed of any one selected from a two-layer structure of Ca / Ag, a Li:Al alloy, and a Mg:Ag alloy. The first cathode CA1 and the second cathode CA2 serve as semi-transparent electrodes that semi-transmit light. The thickness of the second cathode CA2 is preferably formed thinner than that of the first cathode CA1 to reduce the loss of the amount of light emitted from the first light emitting layer OL1.

[0154] The transparent conductive adhesive (not shown) used to bond the first light emitting element LE1 and the second light emitting element LE2 can be formed by a transparent adhesive monomer, and a conductive polymer material or a combination of ITO nanopowder. The transparent adhesive monomer can be selected from any one of acrylic monomers, epoxy monomers, ether monomers, and combinations thereof. In addition, the conductive polymer can be selected from any one of polyacetylene, polypyrrole, polythiophene, poly(3-alkylthiophene), polyphenylene sulfide, poly-p-phenylene sulfide, polyphenylene vinylene, poly-p-phenylene vinylene, poly-thiophene vinylene, polyphenylene, poly-p-phenylene, polyazulene, polyfuran, polyaniline, polyselenophene, polytellurophene, and combinations thereof.

[0155] According to the electroluminescent element of the eighth example according to the present disclosure, the magenta light emitted from the first light emitter M of the first light emitting element LE1 is incident on the second light emitter G through the first color filter (i.e., the red color filter), and then is emitted to the outside through the second anode AN2 and the second transparent substrate SUB2. The magenta light emitted from the first light emitter M is converted into red light after passing through the first color filter CF1, and then converted into blue light after passing through the second color filter CF2. Therefore, since the light emitted from the first light emitting element LE1 is combined with the light emitted from the second light emitting element LE2 and emitted to the outside, it is possible to ensure that the effect of obtaining light with high brightness and high resolution is obtained.

[0156] According to the electroluminescent element of the first to eighth examples of the present disclosure described in detail, by overlapping the first light-emitting element and the second light-emitting element, the light emitted from the first light-emitting element is combined with the light emitted from the second element and emitted to the outside, thereby having the effect of obtaining light with high brightness and high resolution. In addition, a single pixel is made to have light of a first color emitted from the first light-emitting element and light of a second color (different from the first color) emitted from the second light-emitting element, thereby having the effect of obtaining light with high brightness and high resolution.

[0157] The electroluminescent element and the electroluminescent display device according to the present disclosure can be described as follows.

[0158] An electroluminescent element according to an exemplary embodiment of the present disclosure includes: a first light-emitting element provided with a first light emitter emitting light of a first color and a second light emitter emitting light of a second color different from the first color, the first light emitter and the second light emitter being arranged adjacent to each other; and a second light-emitting element provided with a third light emitter, the third light emitter being arranged to overlap with the first light emitter and the second light emitter and emitting light of a third color different from the first color and the second color, wherein the light of the first color and the second color emitted from the first light-emitting element is emitted through the second light-emitting element.

[0159] In an exemplary embodiment, the first light-emitting element may include a first electrode and a second electrode, the first electrode being disposed on a first surface of the first light emitter and the second light emitter, the second electrode being disposed on a second surface of the first light emitter and the second light emitter opposite to the first surface to face the first electrode, the second light-emitting element may include a third electrode and a fourth electrode, the third electrode being disposed on the first surface of the third light emitter, the fourth electrode being disposed on the second surface of the third light emitter opposite to the first surface to face the third electrode, and the second electrode and the third electrode may be bonded to each other.

[0160] In addition, in an exemplary embodiment, the first electrode may be a first anode that reflects light from the first light emitter and the second light emitter, the second electrode may be a first cathode that transmits a portion of each of the light emitted from the first light emitter and the second light emitter, the third electrode may be a second cathode that transmits a portion of the light emitted from the first cathode, and the fourth electrode may be a second anode that transmits light emitted from the third light emitter.

[0161] In addition, the first light emitter may emit red light, the second light emitter may emit blue light, and the third light emitter may emit green light.

[0162] In addition, the first light emitter may emit red light, the second light emitter may emit green light, and the third light emitter may emit blue light.

[0163] In addition, the first light emitter may emit green light, the second light emitter may emit blue light, and the third light emitter may emit red light.

[0164] According to another exemplary embodiment of the present disclosure, an electroluminescent element includes: a first light-emitting element, provided with a first light emitter emitting light of a first color and a second light emitter emitting light of a second color different from the first color, the first light emitter and the second light emitter being arranged adjacent to each other; and a second light-emitting element, provided with a third light emitter and a fourth light emitter, the third light emitter being arranged to overlap with the first light emitter and emit light of the second color, the fourth light emitter being arranged to overlap with the second light emitter and emit light of the third color, the third light emitter and the fourth light emitter being arranged adjacent to each other, wherein light emitted from the first light-emitting element is emitted through the second light-emitting element.

[0165] In an exemplary embodiment, the first light-emitting element may include a first electrode and a second electrode, the first electrode being disposed on a first surface of the first light emitter and the second light emitter, the second electrode being disposed on a second surface of the first light emitter and the second light emitter opposite to the first surface to face the first electrode, the second light-emitting element may include a third electrode and a fourth electrode, the third electrode being disposed on a first surface of the third light emitter and the fourth light emitter, the fourth electrode being disposed on a second surface of the third light emitter and the fourth light emitter opposite to the first surface to face the third electrode, and the second electrode and the third electrode may be bonded to each other.

[0166] In addition, the first electrode can be a first anode that reflects light from the first light emitter and the second light emitter; the second electrode can be a first cathode that transmits a portion of each of the light emitted from the first light emitter and the second light emitter; the third electrode can be a second cathode that transmits a portion of the light emitted from the first cathode; and the fourth electrode can be a second anode that transmits light emitted from the third light emitter.

[0167] In addition, the first light emitter may emit red light, the second light emitter may emit blue light, the third light emitter may emit blue light, and the fourth light emitter may emit green light.

[0168] In addition, the first light emitter may emit red light, the second light emitter may emit green light, the third light emitter may emit green light, and the fourth light emitter may emit blue light.

[0169] According to another exemplary embodiment of the present disclosure, an electroluminescent element includes: a first light-emitting element, provided with a first light emitter emitting light of a first color, and a color filter layer, the color filter layer is arranged to overlap with the first light emitter and has a first color filter of a second color different from the first color and a second color filter of a third color different from the first color and the second color, the first color filter and the second color filter are arranged to be adjacent to each other; and a second light-emitting element, provided with a second light emitter, the second light emitter is arranged to overlap with the first light emitter and the color filter layer and emits light of a fourth color different from the first color to the third color, wherein the light emitted from the first light-emitting element is emitted through the color filter layer and the second light-emitting element.

[0170] In an exemplary embodiment, the first light-emitting element may include a first electrode and a second electrode, the first electrode being disposed on a first surface of the first light emitter, and the second electrode being disposed on a second surface of the first light emitter opposite to the first surface to face the first electrode; the second light-emitting element may include a third electrode and a fourth electrode, the third electrode being disposed on the first surface of the second light emitter, and the fourth electrode being disposed on the second surface of the second light emitter opposite to the first surface to face the third electrode; and a color filter layer may be disposed between the second electrode and the third electrode.

[0171] In addition, the first electrode can be a first anode that reflects light from the first light emitter; the second electrode can be a first cathode that transmits a portion of the light emitted from the first light emitter; the third electrode can be a second cathode that transmits a portion of the light emitted from the first color filter and the second color filter; and the fourth electrode can be a second anode that transmits light emitted from the second light emitter.

[0172] In addition, the first light emitter may emit yellow light, the first color filter may be a red color filter, the second color filter may be a green color filter, and the second light emitter may emit blue light.

[0173] In addition, the first light emitter may emit cyan light, the first color filter may be a blue color filter, the second color filter may be a green color filter, and the second light emitter may emit red light.

[0174] In addition, the first light emitter may emit magenta light, the first color filter may be a red color filter, the second color filter may be a blue color filter, and the second light emitter may emit green light.

[0175] In the above exemplary embodiments, the first anode may be formed by any one selected from Ni, Cr, Al, Ag, and a three-layer structure of ITO / Ag / ITO and a two-layer structure of Al / ITO; the first cathode and the second cathode may be formed by any one selected from a two-layer structure of Ca / Ag, a Li:Al alloy, and a Mg:Ag alloy; and the second anode may be formed by any one selected from Ni, Cr, Al, Ag, and a three-layer structure of ITO / Ag / ITO and a two-layer structure of Al / ITO.

[0176] In addition, the first light emitting element and the second light emitting element may be bonded to each other by a transparent conductive adhesive.

[0177] In addition, the transparent conductive adhesive can be formed by a transparent adhesive monomer, and a conductive polymer material or an ITO nanopowder composition; the transparent adhesive monomer can be selected from any one of an acrylic monomer, an epoxy monomer, an ether monomer and a combination thereof; the conductive polymer can be selected from any one of polyacetylene, polypyrrole, polythiophene, poly(3-alkylthiophene), polyphenylene sulfide, polyp-phenylene sulfide, polyphenylene vinylene, polyp-phenylene vinylene, polythiophene vinylene, polyphenylene, polyp-phenylene, polyazulene, polyfuran, polyaniline, polyselenophene, polytellurophene and a combination thereof.

[0178] An electroluminescent display device according to an exemplary embodiment of the present disclosure includes: scan lines and data lines, which are arranged to cross each other; a switching thin film transistor, which performs a switching operation on a data signal supplied through the data line in response to a scan signal supplied through the scan line; a storage capacitor, which stores the data signal output from the switching thin film transistor as a data voltage; a driving thin film transistor, which supplies a driving current according to the data voltage stored in the storage capacitor; and an electroluminescent element defined in the exemplary embodiment and which emits light according to the driving current.

[0179] As described above, although the exemplary embodiments of the present disclosure have been described in more detail with reference to the accompanying drawings, the present disclosure need not be limited to the above exemplary embodiments, and various modifications may be made within the scope of the technical concept of the present disclosure. Therefore, the exemplary embodiments disclosed in the present disclosure are not intended to limit the technical concept of the present disclosure, but rather describe the present disclosure, and the scope of the technical concept of the present disclosure is not limited to these exemplary embodiments. Therefore, the above exemplary embodiments should be understood to be exemplary and not restrictive in all aspects. The scope of protection of the present disclosure should be interpreted by the attached claims, and all technical concepts within their equivalent scope should be interpreted as included within the scope of the present disclosure.

Claims

1. An electroluminescent element, comprising: A first light emitting element is provided with a first light emitter emitting light of a first color and a second light emitter emitting light of a second color different from the first color, wherein the first light emitter and the second light emitter are arranged adjacent to each other; as well as a second light emitting element, provided with a third light emitter and a fourth light emitter, wherein the third light emitter is arranged to overlap with the first light emitter and emit light of the second color, the fourth light emitter is arranged to overlap with the second light emitter and emit light of the third color, and the third light emitter and the fourth light emitter are arranged adjacent to each other, The light emitted from the first light emitting element is emitted to the outside through the second light emitting element.

2. The electroluminescent element according to claim 1, wherein The first light emitting element includes a first electrode and a second electrode, the first electrode is disposed on a first surface of the first light emitter and the second light emitter, and the second electrode is disposed on a second surface of the first light emitter and the second light emitter opposite to the first surface to face the first electrode; The second light emitting element includes a third electrode and a fourth electrode, the third electrode being disposed on a first surface of the third light emitter and the fourth light emitter, the fourth electrode being disposed on a second surface of the third light emitter and the fourth light emitter opposite to the first surface to face the third electrode; and The second electrode and the third electrode are bonded to each other.

3. The electroluminescent element according to claim 2, wherein The first electrode is a first anode that reflects light from the first light emitter and the second light emitter, The second electrode is a first cathode that transmits light emitted from the first light emitter and the second light emitter, The third electrode is a second cathode that transmits light emitted from the first cathode, and The fourth electrode is a second anode that transmits light emitted from the third light emitter.

4. The electroluminescent element according to claim 3, wherein The first light emitter emits red light, the second light emitter emits blue light, the third light emitter emits blue light, and the fourth light emitter emits green light.

5. The electroluminescent element according to claim 3, wherein The first light emitter emits red light, the second light emitter emits green light, the third light emitter emits green light, and the fourth light emitter emits blue light.

6. An electroluminescent element, comprising: a first light emitting element provided with a first light emitter emitting light of a first color, and a color filter layer, the color filter layer being arranged to overlap with the first light emitter and having a first color filter of a second color different from the first color and a second color filter of a third color different from the first color and the second color, the first color filter and the second color filter being arranged adjacent to each other; as well as a second light emitting element provided with a second light emitter, the second light emitter being arranged to overlap with the first light emitter and the color filter layer and emitting light of a fourth color different from the first to third colors, wherein the light emitted from the first light emitting element is emitted through the color filter layer and the second light emitting element, Wherein, the color filter layer is arranged between the first light emitting element and the second light emitting element.

7. The electroluminescent element according to claim 6, wherein The first light emitting element includes a first electrode and a second electrode, the first electrode is disposed on a first surface of the first light emitter, and the second electrode is disposed on a second surface of the first light emitter opposite to the first surface to face the first electrode; The second light emitting element includes a third electrode and a fourth electrode, the third electrode being disposed on a first surface of the second light emitter, the fourth electrode being disposed on a second surface of the second light emitter opposite to the first surface to face the third electrode; and The color filter layer is disposed between the second electrode and the third electrode.

8. The electroluminescent element according to claim 7, wherein The first electrode is a first anode that reflects light from the first light emitter. The second electrode is a first cathode that transmits light emitted from the first light emitter. The third electrode is a second cathode that transmits light emitted from the first color filter and the second color filter, and The fourth electrode is a second anode that transmits light emitted from the second light emitter.

9. The electroluminescent element according to claim 8, wherein The first light emitter emits yellow light, the first color filter is a red color filter, the second color filter is a green color filter, and the second light emitter emits blue light.

10. The electroluminescent element according to claim 8, wherein The first light emitter emits cyan light, the first color filter is a blue color filter, the second color filter is a green color filter, and the second light emitter emits red light.

11. The electroluminescent element according to claim 8, wherein The first light emitter emits magenta light, the first color filter is a red color filter, the second color filter is a blue color filter, and the second light emitter emits green light.

12. The electroluminescent element according to claim 8, wherein The first anode is formed of any one selected from Ni, Cr, Al, Ag, a three-layer structure of ITO / Ag / ITO, and a two-layer structure of Al / ITO; The first cathode and the second cathode are formed of any one selected from a Ca / Ag two-layer structure, a Li:Al alloy, and a Mg:Ag alloy; and The second anode is formed of any one selected from Ni, Cr, Al, Ag, a three-layer structure of ITO / Ag / ITO, and a two-layer structure of Al / ITO.

13. The electroluminescent element according to claim 6, wherein The first light emitting element and the second light emitting element are bonded to each other by a transparent conductive adhesive.

14. The electroluminescent element according to claim 13, wherein The transparent conductive adhesive is formed by a transparent adhesive monomer and a conductive polymer material or an ITO nano powder. The transparent adhesive monomer is selected from any one of acrylic monomers, epoxy monomers, ether monomers and combinations thereof; and The conductive polymer is selected from any one of polyacetylene, polypyrrole, polythiophene, poly(3-alkylthiophene), polyphenylene sulfide, poly-p-phenylene sulfide, polyphenylene vinylene, poly-p-phenylene vinylene, polythiophene vinylene, polyphenylene, poly-p-phenylene, polyazulene, polyfuran, polyaniline, polyselenophene, polytellurophene and combinations thereof.

15. An electroluminescent display device, comprising: The scan lines and the data lines are arranged to cross each other; a switching thin film transistor that performs a switching operation on a data signal supplied through the data line in response to a scan signal supplied through the scan line; a storage capacitor storing the data signal output from the switching thin film transistor as a data voltage; a driving thin film transistor for supplying a driving current according to the data voltage stored in the storage capacitor; as well as The electroluminescent element according to any one of claims 1 to 11, which emits light in response to the driving current.

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