Light emitting device and electronic device including the same

Abstract

The present invention relates to a light-emitting device and an electronic device including the light-emitting device. The light-emitting device includes a first electrode and a second electrode facing each other, an emission layer between the first electrode and the second electrode, and a charge transport region between the emission layer and the first electrode. Light emitted from the emission layer is transmitted to the outside through the second electrode, the first electrode is a reflective electrode, the first electrode includes a transparent layer and a reflective layer, a distance between i) an interface between the transparent layer of the first electrode and the charge transport region and ii) an interface between the emission layer and the charge transport region is a first resonance distance of light emitted from the emission layer, and a distance between a) an interface between the reflective layer of the first electrode and the transparent layer of the first electrode and b) an interface between the emission layer and the charge transport region is a second resonance distance of light emitted from the emission layer.

Description

[0001] Cross-references to related applications

[0002] This application claims priority and benefit to Korean Patent Application No. 10-2020-0089154, filed on July 17, 2020, which is incorporated herein by reference for all purposes, as fully set forth herein. Technical Field

[0003] Exemplary embodiments of the present invention relate to light-emitting devices and electronic devices including the light-emitting devices. Background Technology

[0004] Organic light-emitting devices (OLEDs) are self-emitting devices. Compared with other devices in this field, OLEDs have a wide viewing angle, high contrast, short response time, and excellent characteristics in terms of brightness, driving voltage, and response speed.

[0005] An OLED may include a first electrode on a substrate and a hole transport region, an emitter layer, an electron transport region, and a second electrode sequentially stacked on the first electrode. Holes supplied from the first electrode can move towards the emitter layer through the hole transport region, and electrons supplied from the second electrode can move towards the emitter layer through the electron transport region. Charge carriers (such as holes and electrons) recombine in the emitter layer to generate excitons. These excitons transition from an excited state to a ground state, thereby generating light.

[0006] The information disclosed in this background section is only for understanding the background of the inventive concept, and therefore, the above information may contain information that does not constitute prior art. Summary of the Invention

[0007] Exemplary embodiments relate to a light-emitting device and an electronic device including the light-emitting device, which simultaneously has low driving voltage, high luminous efficiency and long lifetime.

[0008] Additional aspects will be set forth in part in the description which follows, and will be apparent in part from the description, or may be learned by practice of the invention.

[0009] An exemplary embodiment of the present invention provides a light-emitting device, comprising: a first electrode; a second electrode facing the first electrode; an emitting layer located between the first electrode and the second electrode; and a charge transport region located between the emitting layer and the first electrode. Light emitted from the emitting layer is transmitted to the outside through the second electrode. The first electrode is a reflective electrode, comprising a transparent layer and a reflective layer, and the following formulas 1 and 2 are satisfied:

[0010] Formula 1

[0011] L1-a1≤D1≤L1+a1

[0012] In Formula 1, D1 represents the distance between i) the interface between the transparent layer of the first electrode and the charge transport region, and ii) the interface between the emitting layer and the charge transport region; L1 represents the first resonant distance of the light emitted from the emitting layer; and a1 is a real number in the range of approximately 0 nanometers (nm) to approximately 50 nm.

[0013] Formula 2

[0014] L2-a2≤D2≤L2+a2

[0015] In Formula 2, D2 is the distance between a) the interface between the reflective layer and the transparent layer of the first electrode and b) the interface between the emitting layer and the charge transport region, L2 is the second resonant distance of the light emitted from the emitting layer, and a2 is a real number in the range of approximately 0 nm to approximately 50 nm.

[0016] Another exemplary embodiment of the present invention provides a light-emitting device, comprising: a first electrode; a second electrode facing the first electrode; an emission unit of number x stacked between the first electrode and the second electrode; and x-1 charge-generating layers located between every two adjacent emission units in the x-1 emission units, each of the x-1 charge-generating layers comprising an n-type charge-generating layer and a p-type charge-generating layer, wherein x is an integer of 2 or greater, and each of the x emission units comprises a charge transport region and an emission layer sequentially stacked above the first electrode. Light emitted from the x-1 emission units is transmitted to the outside through the second electrode, the first electrode being a reflective electrode comprising a transparent layer and a reflective layer, and the following formulas y and y+1 are satisfied:

[0017] Formula y

[0018] L y -a y ≤D y ≤L y +a y

[0019] In formula y, D y Let L be the distance between i) the interface between the transparent layer of the first electrode and the charge transport region of the y-th emitter in a plurality of x emitter units, and ii) the distance between the emitter layer of the y-th emitter in a plurality of x emitter units and the interface between the charge transport region of the y-th emitter in a plurality of x emitter units. y Let a be the y-th resonant distance of light emitted from the emission layer of the y-th emission unit among x emission units, and a y For real numbers in the range of approximately 0 nm to approximately 50 nm,

[0020] Formula y+1

[0021] L y+1 -a y+1 ≤D y+1 ≤L y+1 +a y+1

[0022] In the formula y+1, D y+1 Let L be the distance between (a) the interface between the reflective layer and the transparent layer of the first electrode, and (b) the distance between the interface between the emission layer of the y-th emission unit in a number of x emission units and the interface between the charge transport region of the y-th emission unit in a number of x emission units. y+1 Let a be the (y+1)th resonant distance of light emitted from the emission layer of the y-th emission unit among x emission units, and a y+1 For real numbers in the range of approximately 0 nm to approximately 50 nm.

[0023] Another exemplary embodiment of the present invention provides a light-emitting device, which may include: a first electrode; a second electrode facing the first electrode; a first emitting unit located between the first electrode and the second electrode; a second emitting unit located between the first emitting unit and the second electrode; and a charge-generating layer located between the first emitting unit and the second emitting unit and including an n-type charge-generating layer and a p-type charge-generating layer. The first emitting unit includes a first charge transport region and a first emitting layer sequentially stacked on the first electrode, and the second emitting unit includes a second charge transport region and a second emitting layer sequentially stacked on the charge-generating layer. Light emitted from the first emitting unit and the second emitting unit is transmitted to the outside through the second electrode. The first electrode is a reflective electrode, and the first electrode includes a transparent layer and a reflective layer. Furthermore, the following formulas 11, 12, 22, and 23 are satisfied:

[0024] Formula 11

[0025] L 11 -a 11 ≤D 11 ≤L 11 +a 11

[0026] In Formula 11, D 11 L represents the distance between i) the interface between the transparent layer of the first electrode and the first charge transport region of the first emitter unit, and ii) the interface between the first emitter layer of the first emitter unit and the first charge transport region of the first emitter unit. 11 Let a be the first resonant distance of the light emitted from the first emission layer of the first emission unit. 11 For real numbers in the range of approximately 0 nm to approximately 50 nm,

[0027] Formula 12

[0028] L 12 -a 12 ≤D 12 ≤L 12 +a 12

[0029] In formula 12, D 12 L represents the distance between (a) the interface between the reflective layer and the transparent layer of the first electrode, and (b) the interface between the first emitting layer and the first charge transport region of the first emitting unit. 12 The second resonant distance of the light emitted from the first emitting layer of the first emitting unit, and a 12 For real numbers in the range of approximately 0 nm to approximately 50 nm,

[0030] Formula 22

[0031] L 22 -a 22 ≤D 22 ≤L 22 +a 22

[0032] In formula 22, D 22 L represents the distance between (iii) the interface between the transparent layer of the first electrode and the first charge transport region of the first emitting unit, and (iv) the interface between the second emitting layer of the second emitting unit and the second charge transport region of the second emitting unit. 22 Let a be the second resonant distance of the light emitted from the second emission layer of the second emission unit. 22 For real numbers in the range of approximately 0 nm to approximately 50 nm, and

[0033] Formula 23

[0034] L 23 -a 23 ≤D 23 ≤L 23 +a 23

[0035] In formula 23, D 23 L represents the distance between c) the interface between the reflective layer and the transparent layer of the first electrode and d) the interface between the second emission layer and the second charge transport region of the second emission unit. 23 The third resonant distance is the light emitted from the second emission layer of the second emission unit, and a 23 For real numbers in the range of approximately 0 nm to approximately 50 nm.

[0036] It should be understood that both the foregoing general description and the following detailed description are exemplary and illustrative, and are intended to provide further explanation of the claimed invention. Attached Figure Description

[0037] The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the invention and, together with the description, serve to explain the inventive concept.

[0038] Figure 1 This is a schematic diagram of a light-emitting device 10 according to an exemplary embodiment.

[0039] Figure 2 This is a schematic diagram of a light-emitting device 20 according to another exemplary embodiment.

[0040] Figure 3 This is a schematic diagram of a light-emitting device 30 according to yet another exemplary embodiment. Detailed Implementation

[0041] In the following description, numerous specific details are set forth for illustrative purposes to provide a thorough understanding of various exemplary embodiments of the invention. As used herein, “embodiment” is a non-limiting example of an apparatus or method employing one or more of the inventive concepts disclosed herein. However, it will be apparent that various exemplary embodiments may be practiced without these specific details or with one or more equivalent arrangements. In other instances, well-known structures and apparatuses are illustrated in block diagram form to avoid unnecessarily obscuring the various exemplary embodiments. Furthermore, the various exemplary embodiments may be different, but not necessarily exclusive. For example, specific shapes, configurations, and characteristics of exemplary embodiments may be used in or implemented in another exemplary embodiment without departing from the inventive concept.

[0042] Unless otherwise specified, the illustrated exemplary embodiments should be understood as providing exemplary features of different details of how the inventive concept can be implemented in practice. Therefore, unless otherwise specified, features, components, modules, layers, films, panels, areas and / or aspects of the various embodiments (hereinafter collectively referred to as “elements”) may be combined, separated, interchanged and / or rearranged without departing from the inventive concept.

[0043] In the accompanying drawings, the dimensions and relative dimensions of elements may be exaggerated for clarity and / or descriptive purposes. When exemplary embodiments can be implemented differently, a particular process sequence may be performed in a different order than that described. For example, two consecutively described processes may be performed substantially simultaneously, or in the reverse order of their description. Furthermore, the same reference numerals refer to the same elements.

[0044] When a component or layer is referred to as "on another component or layer," "connected to," or "coupled to" another component or layer, the component may be directly on, directly connected to, or coupled to the other component or layer, or there may be intermediate components or layers present. However, when a component or layer is referred to as "directly on another component or layer," "directly connected to," or "directly coupled to" another component or layer, there are no intermediate components or layers present. Therefore, the term "connection" can refer to a physical connection, electrical connection, and / or fluid connection with or without intermediate components. Furthermore, the D1, D2, and D3 axes are not limited to the three axes of a Cartesian coordinate system (such as the x, y, and z axes) and can be interpreted in a broader sense. For example, the D1, D2, and D3 axes can be perpendicular to each other, or they can represent different directions that are not perpendicular to each other. For the purposes of this disclosure, "at least one of X, Y, and Z" and "at least one selected from the group consisting of X, Y, and Z" can be interpreted as only X, only Y, only Z, or any combination of two or more of X, Y, and Z, such as, for example, XYZ, XYY, YZ, and ZZ. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0045] Although the terms “first,” “second,” etc., may be used herein to describe various types of elements, these elements should not be limited by these terms. These terms are used to distinguish one element from another. Therefore, without departing from the teachings of this disclosure, the first element discussed below may be referred to as the second element.

[0046] For descriptive purposes, spatially relative terms such as “below,” “under,” “below,” “down,” “above,” “above,” “higher,” and “side” (e.g., as in “sidewall”) may be used herein to describe the relationship of one element relative to another(s) as illustrated in the accompanying drawings. In addition to the orientations depicted in the drawings, the spatially relative terms are intended to cover different orientations of the device in use, operation, and / or manufacture. For example, if the device in the drawings is flipped, an element described as “below” or “under” other elements or features will consequently be oriented “above” other elements or features. Thus, the exemplary term “below” can cover both above and below orientations. Furthermore, the device may be oriented in other ways (e.g., rotated 90 degrees or oriented in other orientations), and therefore, the spatially relative descriptors used herein are interpreted accordingly.

[0047] The terminology used herein is for the purpose of describing particular embodiments and is not intended to be limiting. As used herein, unless the context clearly indicates otherwise, the singular forms “a” and “the” are intended to include the plural forms as well. Furthermore, when used in this specification, the terms “comprising” and / or “including” specify the presence of stated features, integrals, steps, operations, elements, components, and / or groups thereof, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or groups thereof. It should also be noted that, as used herein, the terms “basically,” “about,” and other similar terms are used as approximate terms rather than terms of degree, and are therefore utilized to account for the inherent biases of measured, calculated, and / or provided values ​​recognized by those skilled in the art.

[0048] Unless otherwise specified, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. Terms such as those defined in common dictionaries shall be interpreted as having the same meaning as they have in the context of the relevant art and shall not be interpreted in an idealized or overly formal sense unless specifically defined herein.

[0049] Figure 1 Description

[0050] Figure 1 The light-emitting device 10 includes: a first electrode AN; a second electrode CA facing the first electrode AN; an emitting layer EM located between the first electrode AN and the second electrode CA; and a charge transport region CT located between the emitting layer EM and the first electrode AN.

[0051] The charge transport region (CT) can have i) a single-layer structure composed of a single material, ii) a single-layer structure composed of at least two different materials, or iii) a multi-layer structure including various different materials.

[0052] The first electrode AN can be a hole injection electrode (e.g., an anode), and the second electrode CA can be an electron injection electrode (i.e., a cathode).

[0053] Figure 1 The first electrode AN can be a hole injection electrode, and the charge transport region CT can be a hole transport region.

[0054] The hole transport region may include a hole injection layer, a hole transport layer, an electron blocking layer, a buffer layer, or a combination thereof.

[0055] The hole transport region may include compounds having hole transport properties. The hole transport region may include compounds containing dibenzofuran, compounds containing dibenzothiophene, compounds containing carbazole, compounds containing fluorene, compounds containing amines, p-dopers, or any combination thereof.

[0056] Despite Figure 1 It is not shown in the figure, but another charge transport region (e.g., an electron transport region) may be further arranged between the emitter layer EM and the second electrode CA.

[0057] Figure 1 The first electrode AN can be a hole injection electrode, the charge transport region CT can be a hole transport region, and the electron transport region can be further arranged between the emitter layer EM and the second electrode CA.

[0058] The electron transport region can have i) a single-layer structure composed of a single material, ii) a single-layer structure composed of at least two different materials, or iii) a multi-layer structure comprising various different materials. The electron transport region may include a hole blocking layer, an electron transport layer, an electron injection layer, or a combination thereof.

[0059] Light emitted from the emitting layer EM can be transmitted to the outside of the light-emitting device 10 through the second electrode CA.

[0060] The emitting layer (EM) can emit blue, green, red, and / or white light.

[0061] In some exemplary embodiments, the light emitted from the emitting layer EM may be blue light having a maximum emission wavelength in the range of about 440 nm to about 495 nm (e.g., in the range of about 440 nm to about 480 nm), green light having a maximum emission wavelength in the range of about 495 nm to about 570 nm (e.g., in the range of about 510 nm to about 550 nm), or red light having a maximum emission wavelength in the range of about 590 nm to about 750 nm (e.g., in the range of about 610 nm to about 640 nm).

[0062] The light emitted from the emitting layer EM can be blue light.

[0063] The first electrode AN can be a reflective electrode, and the first electrode AN can include a transparent layer AT and a reflective layer AR.

[0064] In some exemplary embodiments, such as Figure 1 As shown, the transparent layer AT of the first electrode AN can be arranged between the reflective layer AR of the first electrode AN and the charge transport region CT.

[0065] The light-emitting device 10 can satisfy Formula 1:

[0066] Formula 1

[0067] L1-a1≤D1≤L1+a1

[0068] In Formula 1, D1 can be the distance between i) the interface between the transparent layer AT of the first electrode AN and the charge transport region CT and ii) the interface between the emitting layer EM and the charge transport region CT, L1 can be the first resonant distance of the light emitted from the emitting layer EM, and a1 can be a real number in the range of approximately 0 nm to approximately 50 nm.

[0069] For example, a1 can be a real number in the range of approximately 40 nm to approximately 50 nm, a real number in the range of approximately 30 nm to approximately 40 nm, a real number in the range of approximately 20 nm to approximately 30 nm, a real number in the range of approximately 10 nm to approximately 20 nm, or a real number in the range of approximately 0 nm to approximately 10 nm.

[0070] When the light-emitting device 10 satisfies Formula 1, the thickness of the region (in which organic matter is basically arranged) between the interface between the transparent layer AT of the first electrode AN and the charge transport region CT and the interface between the emission layer EM and the charge transport region CT can be kept relatively small. Therefore, the light-emitting device 10 has low driving voltage, long life and high external light extraction efficiency.

[0071] In addition, the light-emitting device 10 can satisfy formula 2:

[0072] Formula 2

[0073] L2-a2≤D2≤L2+a2

[0074] In Formula 2, D2 can be the distance between a) the interface between the reflective layer AR of the first electrode AN and the transparent layer AT of the first electrode AN and b) the interface between the emitting layer EM and the charge transport region CT, L2 can be the second resonant distance of the light emitted from the emitting layer EM, and a2 can be a real number in the range of approximately 0 nm to approximately 50 nm.

[0075] For example, a2 can be a real number in the range of approximately 40 nm to approximately 50 nm, a real number in the range of approximately 30 nm to approximately 40 nm, a real number in the range of approximately 20 nm to approximately 30 nm, a real number in the range of approximately 10 nm to approximately 20 nm, or a real number in the range of approximately 0 nm to approximately 10 nm.

[0076] When the light-emitting device 10 satisfies Equation 2, the reflective layer AR and the emitting layer EM of the first electrode AN can be spaced apart from each other at an appropriate distance, and therefore, the light loss due to quenching caused by surface plasmon polaritons (SPP) and light loss due to waveguide (i.e., light emitted from the emitting layer EM) can be significantly reduced. Therefore, the light-emitting device 10 can have high external light extraction efficiency.

[0077] In some exemplary embodiments, L1 in Formula 1 can be represented by Formula 1A:

[0078] Formula 1A

[0079] L1={[(m1-1)+0.5]×λ} / 2r1

[0080] In Formula 1A, λ represents the maximum emission wavelength of light emitted from the emitting layer EM, r1 represents the effective refractive index of the region between the transparent layer AT of the first electrode AN and the emitting layer EM, and m1 can be 1.

[0081] r1 can vary depending on the compound included in the region between the transparent layer AT and the emitter layer EM of the first electrode AN, and r1 can, for example, be in the range of about 1.5 to about 2.1.

[0082] The region located between the transparent layer AT and the emission layer EM of the first electrode AN can be, for example, the charge transport region CT.

[0083] In some exemplary embodiments, the “effective refractive index” as used herein can be evaluated using an elliptic apparatus. For example, the effective refractive index of the region between the transparent layer AT and the emitter layer EM of the first electrode AN can be evaluated using an elliptic apparatus. In some exemplary embodiments, the effective refractive index can be evaluated by measuring the refractive index of a layer using an elliptic apparatus, wherein the layer is formed to a predetermined thickness (e.g., 30 nm) by depositing material included in the region between the transparent layer AT and the emitter layer EM of the first electrode AN on a glass substrate.

[0084] In one or more exemplary embodiments, L2 can be represented by Equation 2A in Equation 2:

[0085] Formula 2A

[0086] L2={[(m2-1)+0.5]×λ} / 2r2

[0087] In Equation 2A, λ represents the maximum emission wavelength of light emitted from the emitting layer EM, r2 represents the effective refractive index of the region between the reflective layer AR and the emitting layer EM of the first electrode AN, and m2 can be 2.

[0088] r2 can vary depending on the compound included in the region between the reflective layer AR and the emitting layer EM of the first electrode AN, and r2 can, for example, be in the range of about 1.6 to about 2.5.

[0089] The region between the reflective layer AR and the emitting layer EM of the first electrode AN can be, for example, the charge transport region CT and the transparent layer AT of the first electrode AN.

[0090] The effective refractive index of the region between the reflective layer AR and the emitting layer EM of the first electrode AN can be measured using the method described herein.

[0091] In one or more exemplary embodiments, the light-emitting device 10 may satisfy Formula 3:

[0092] Formula 3

[0093] n1≥n2

[0094] In Formula 3, n1 can be the refractive index of the transparent layer AT of the first electrode AN, and n2 can be the refractive index of the layer in the charge transport region CT that is in direct contact with the transparent layer AT of the first electrode AN.

[0095] In one or more exemplary embodiments, the light-emitting device 10 may satisfy Formula 4:

[0096] Formula 4

[0097] n1-n2≥0.1

[0098] You can understand n1 and n2 in Formula 4 by referring to the descriptions of n1 and n2 provided in this article.

[0099] In one or more exemplary embodiments, blue light (e.g., blue light having a maximum emission wavelength in the range of about 450 nm to about 495 nm) is emitted from the emitting layer EM, and D1 in Formula 1 can be in the range of about 10 nm to about 60 nm, for example, about 30 nm to about 60 nm.

[0100] In one or more exemplary embodiments, blue light (e.g., blue light having a maximum emission wavelength in the range of about 450 nm to about 495 nm) is emitted from the emitting layer EM, and D2 in Formula 2 can be in the range of about 50 nm to about 180 nm, for example, about 100 nm to about 180 nm.

[0101] In one or more exemplary embodiments, green light (e.g., green light having a maximum emission wavelength in the range of about 495 nm to about 570 nm) is emitted from the emitting layer EM, and D1 in Formula 1 can be in the range of about 40 nm to about 95 nm, for example, about 50 nm to about 85 nm.

[0102] In one or more exemplary embodiments, green light (e.g., green light having a maximum emission wavelength in the range of about 495 nm to about 570 nm) is emitted from the emitting layer EM, and D2 in Formula 2 can be in the range of about 80 nm to about 215 nm, for example, about 100 nm to about 195 nm.

[0103] In one or more exemplary embodiments, red light (e.g., red light having a maximum emission wavelength in the range of about 590 nm to about 750 nm) is emitted from the emitting layer EM, and D1 in Formula 1 can be in the range of about 60 nm to about 145 nm, for example, about 60 nm to about 125 nm.

[0104] In one or more exemplary embodiments, red light (e.g., red light having a maximum emission wavelength in the range of about 590 nm to about 750 nm) is emitted from the emitting layer EM, and D2 in Formula 2 can be in the range of about 130 nm to about 225 nm, for example, about 150 nm to about 205 nm.

[0105] In one or more exemplary embodiments, the thickness of the transparent layer AT of the first electrode AN can be in the range of about 40 nm to about 130 nm, for example, about 60 nm to about 120 nm.

[0106] The first electrode AN can be a conductive layer capable of injecting charges (e.g., holes).

[0107] The transparent layer AT of the first electrode AN can be a metal oxide layer. The metal in the metal oxide layer can be, for example, indium (In), zinc (Zn), tin (Sn), tungsten (W), molybdenum (Mo), or any combination thereof. In some exemplary embodiments, the metal oxide of the metal oxide layer can be indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide (SnO2), zinc oxide (ZnO), tungsten oxide (WO3), molybdenum oxide (MoO3), or any combination thereof. The transparent layer AT of the first electrode AN can be an ITO layer.

[0108] The reflective layer AR of the first electrode AN can be a metal layer. In some exemplary embodiments, the metal in the metal layer can be magnesium (Mg), silver (Ag), aluminum (Al), lithium (Li), calcium (Ca), indium (In), or any combination thereof. In some exemplary embodiments, the reflective layer AR of the first electrode AN can be an Al layer, an Ag layer, or an Al-Ag alloy layer.

[0109] Figure 2 Description

[0110] Figure 2 The light-emitting device 20 shown has a series structure.

[0111] The light-emitting device 20 may include: a first electrode AN; a second electrode CA facing the first electrode AN; and x number of emitting units EU1, ..., EU1 stacked between the first electrode AN and the second electrode CA. x-1 and EU x ; and the number of transmitting units EU1, ..., EU1 located in x units. x-1 and EU x Between each pair of adjacent emitter units are x-1 charge generation layers CG1, ..., CG x-1 x-1 charge generation layers CG1, ..., CG x-1 Each charge generation layer in the system includes an n-type charge generation layer and a p-type charge generation layer.

[0112] x can be an integer of 2 or greater. In some embodiments, x can be 2 or 3.

[0113] The emitting units EU1, ..., EU in the light-emitting device 20 x-1 and EU x These may include charge transport regions CT1, ..., CT1, sequentially stacked above the first electrode AN. x-1 or CT x and the emitter layers EM1, ..., EM x-1 or EM x You can refer to Figure 1 The description of the charge transport region CT and the emitting layer EM of the light-emitting device 10 is used to understand the charge transport regions CT1, ..., CT1 included in the light-emitting device 20. x-1 and CT x and the emitter layers EM1, ..., EM x-1 and EM x .

[0114] From the transmitting units EU1, ..., EU x-1 and EU x The emitted light can be transmitted to the outside of the light-emitting device 20 through the second electrode CA.

[0115] The first electrode AN can be a reflective electrode, and the first electrode AN can include a transparent layer AT and a reflective layer AR. This can be seen from [reference needed]. Figure 1 The descriptions of the first electrode AN and the second electrode CA of the light-emitting device 10 shown are understood in relation to the first electrode AN and the second electrode CA of the light-emitting device 20.

[0116] The light-emitting device 20 can satisfy the formula y:

[0117] Formula y

[0118] L y -a y ≤D y ≤L y +a y

[0119] In formula y, D y This could be i) the interface between the transparent layer AT of the first electrode AN and the charge transport region CT1 of the first emitting unit EU1, ..., EU1, and ii) a number of emitting units EU1, ..., EU1 of size x. x-1 and EU x The y-th emission unit has an emission layer and x emission units EU1, ..., EU1. x-1 and EU x The distance between the interfaces of the charge transport regions of the y-th emitting unit, L y It can be from x number of transmitting units EU1, ..., EU x-1 and EU x The y-th resonant distance of the light emitted by the emission layer of the y-th emitting unit, and a y It can be a real number in the range of approximately 0 nm to approximately 50 nm. This can be obtained by referring to... Figure 1 To understand a, use the description of a1 in the text. y .

[0120] In some exemplary embodiments, in Figure 2 In the light-emitting device 20, i) the interface between the transparent layer AT of the first electrode AN and the charge transport region CT1 of the first emitting unit EU1 and ii) the (x-1)th emitting unit EU x-1 EM emission layer x-1 With the x-1th launch unit EU x-1 CT of charge transport region x-1 Distance D between interfaces (x-1)(x-1) It can be from the (x-1)th launch unit EU x-1 EM emission layer x-1 The x-1th resonant distance of the emitted light ±a (x-1)(x-1) .

[0121] In some exemplary embodiments, in Figure 2 In the light-emitting device 20, i) the interface between the transparent layer AT of the first electrode AN and the charge transport region CT1 of the first emitting unit EU1 and ii) the xth emitting unit EU x EM emission layer x With the xth launch unit EU x CT of charge transport region x Distance D between interfaces xx It can be from the xth transmitting unit EU x EM emission layer x The xth resonant distance of the emitted light ±a xx .

[0122] In addition, the light-emitting device 20 can satisfy the formula y+1:

[0123] Formula y+1

[0124] L y+1 -a y+1 ≤D y+1 ≤L y+1 +a y+1

[0125] In the formula y+1, D y+1 It could be a) the interface between the reflective layer AR and the transparent layer AT of the first electrode AN, and b) x number of emitting units EU1, ..., EU x-1 and EU x The y-th emission unit has an emission layer and x emission units EU1, ..., EU1. x-1 and EU x The distance between the interfaces of the charge transport regions of the y-th emitting unit, L y+1 It can be from x number of transmitting units EU1, ..., EU x-1 and EU x The (y+1)th resonant distance of the light emitted by the emission layer of the y-th emitting unit, and a y+1 It can be a real number in the range of approximately 0 nm to approximately 50 nm. This can be obtained by referring to... Figure 1 To understand a, use the description of a2 in the text. y+1 .

[0126] In some exemplary embodiments, in Figure 2 In the light-emitting device 20, a) the interface between the reflective layer AR of the first electrode AN and the transparent layer AT of the first electrode AN and b) the (x-1)th emitting unit EU x-1 EM emission layer x-1 With the x-1th launch unit EU x-1 CT of charge transport regionx-1 Distance D between interfaces (x-1)x It can be from the (x-1)th launch unit EU x-1 EM emission layer x-1 The xth resonant distance of the emitted light ±a (x-1)x .

[0127] In some exemplary embodiments, in Figure 2 In the light-emitting device 20, a) the interface between the reflective layer AR of the first electrode AN and the transparent layer AT of the first electrode AN and b) the xth emitting unit EU x EM emission layer x With the xth launch unit EU x- CT of charge transport region x Distance D between interfaces x(x+1) It can be from the xth transmitting unit EU x EM emission layer x The xth resonant distance of the emitted light ±a x(x+1) .

[0128] Here, y can be a variable of integers from 1 to x.

[0129] Figure 2 D in 11 and D 12 You can refer to the D provided in this article respectively 11 and D 12 To understand this, we need to refer to the description.

[0130] In some exemplary embodiments, the number of emitting units EU1, ..., EU1 in the light-emitting device 20 is x. x-1 and EU x At least one of them can emit blue light.

[0131] In some exemplary embodiments, the first emitting unit EU1 of the light-emitting device 20 can emit blue light.

[0132] exist Figure 1 The descriptions of the light-emitting device 10 shown, including the electron transport region, the influence of the control resonant distance, and Equations 1A, 2A, 3, and 4, can also be applied to... Figure 2 The light-emitting device 20 shown has x number of emitting units EU1, ..., EU2. x-1 and EU x .

[0133] Figure 3 Description

[0134] Figure 3 The light-emitting device 30 shown has, as Figure 2The light-emitting device 20 is connected in series, where x is 2.

[0135] Figure 3 The light-emitting device 30 includes: a first electrode AN; a second electrode CA facing the first electrode AN; a first emitting unit EU1 located between the first electrode AN and the second electrode CA; a second emitting unit EU2 located between the first emitting unit EU1 and the second electrode CA; and a charge generating layer CG1 located between the first emitting unit EU1 and the second emitting unit EU2 and including an n-type charge generating layer and a p-type charge generating layer.

[0136] The first emitting unit EU1 may include a first charge transport region CT1 and a first emitting layer EM1 that can be sequentially stacked on the first electrode AN, and the second emitting unit EU2 may include a second charge transport region CT2 and a second emitting layer EM2 that can be sequentially stacked on the charge generation layer CG1. (See reference...) Figure 1 The descriptions of the charge transport regions CT in the light-emitting device 10 are for illuminating the first charge transport region CT1 and the second charge transport region CT2 in the light-emitting device 30. These can be understood by referring to... Figure 1 The descriptions of the emitting layers EM of the light-emitting device 10 are understood as follows: first emitting layer EM1 and second emitting layer EM2.

[0137] Light emitted from the first emitting unit EU1 and the second emitting unit EU2 can be transmitted to the outside of the light-emitting device 30 through the second electrode CA.

[0138] The first electrode AN can be a reflective electrode, and the first electrode AN can include a transparent layer AT and a reflective layer AR. This can be seen from [reference needed]. Figure 1 The descriptions of the first electrode AN and the second electrode CA of the light-emitting device 10 shown are understood in relation to the first electrode AN and the second electrode CA of the light-emitting device 30.

[0139] The light-emitting device 30 can satisfy formula 11:

[0140] Formula 11

[0141] L 11 -a 11 ≤D 11 ≤L 11 +a 11

[0142] In Formula 11, D 11 This could be i) the interface between the transparent layer AT of the first electrode AN and the first charge transport region CT1 of the first emitting unit EU1, and ii) the distance between the interface between the first emitting layer EM1 of the first emitting unit EU1 and the first charge transport region CT1 of the first emitting unit EU1. 11It can be the first resonant distance of the light emitted from the first emitting layer EM1 of the first emitting unit EU1, and a 11 It can be a real number in the range of approximately 0 nm to approximately 50 nm. This can be obtained by referring to... Figure 1 To understand a, use the description of a1 in the text. 11 .

[0143] When the light-emitting device 30 satisfies Formula 11, the thickness of the region (in which organic matter is basically arranged) between the interface between the transparent layer AT of the first electrode AN and the first charge transport region CT1 of the first emitting unit EU1 and the interface between the first emitting layer EM1 of the first emitting unit EU1 and the first charge transport region CT1 of the first emitting unit EU1 can be kept relatively small, and therefore the light-emitting device 30 can have low driving voltage, long life and high external light extraction efficiency.

[0144] In some exemplary embodiments, L in Formula 11 11 This can be represented by formula 11A:

[0145] Formula 11A

[0146] L 11 ={[(m 11 -1)+0.5]×λ} / 2r 11

[0147] In Formula 11A, λ can be the maximum emission wavelength of light emitted from the first emission layer EM1 of the first emission unit EU1, and r 11 The effective refractive index represents the region between the transparent layer AT of the first electrode AN and the first emission layer EM1 of the first emission unit EU1, and m 11 It can be 1.

[0148] In addition, the light-emitting device 30 can satisfy formula 12:

[0149] Formula 12

[0150] L 12 -a 12 ≤D 12 ≤L 12 +a 12

[0151] In formula 12, D 12 It can be the distance L between a) the interface between the reflective layer AR and the transparent layer AT of the first electrode AN and b) the interface between the first emission layer EM1 and the first charge transport region CT1 of the first emission unit EU1. 12It can be the second resonant distance of the light emitted from the first emitting layer EM1 of the first emitting unit EU1, and a 12 It can be a real number in the range of approximately 0 nm to approximately 50 nm. This can be obtained by referring to... Figure 1 To understand a, use the description of a2 in the text. 12 .

[0152] When the light-emitting device 30 satisfies Formula 12, the first emitting layer EM1 of the first emitting unit EU1 and the reflective layer AR of the first electrode AN can be spaced apart from each other at an appropriate distance, and therefore, the light loss due to quenching caused by SPP and light loss due to waveguide (i.e., light emitted from the first emitting layer EM1 of the first emitting unit EU1) can be significantly reduced. Therefore, the light-emitting device 30 can have a high external light extraction efficiency.

[0153] In some exemplary embodiments, L in Formula 12 12 This can be represented by formula 12A:

[0154] Formula 12A

[0155] L 12 ={[(m 12 -1)+0.5]×λ} / 2r 12

[0156] In Formula 12A, λ can be the maximum emission wavelength of light emitted from the first emission layer EM1 of the first emission unit EU1, and r 12 The effective refractive index represents the region between the reflective layer AR of the first electrode AN and the first emitter layer EM1 of the first emitter unit EU1, and m 12 It can be 2.

[0157] In addition, the light-emitting device 30 can satisfy formula 22:

[0158] Formula 22

[0159] L 22 -a 22 ≤D 22 ≤L 22 +a 22

[0160] In formula 22, D 22 It could be iii) the distance between the interface between the transparent layer AT of the first electrode AN and the first charge transport region CT1 of the first emitting unit EU1, and iv) the distance between the interface between the second emitting layer EM2 of the second emitting unit EU2 and the second charge transport region CT2 of the second emitting unit EU2, L 22 It can be the second resonant distance of the light emitted from the second emission layer EM2 of the second emission unit EU2, and a22 It can be a real number in the range of approximately 0 nm to approximately 50 nm. This can be obtained by referring to... Figure 1 To understand a, use the description of a1 in the text. 22 .

[0161] When the light-emitting device 30 satisfies Formula 22, the thickness of the region (in which organic matter is basically arranged) between the interface between the transparent layer AT of the first electrode AN and the first charge transport region CT1 of the first emitting unit EU1 and the interface between the second emitting layer EM2 of the second emitting unit EU2 and the second charge transport region CT2 of the second emitting unit EU2 can be kept relatively small, and therefore the light-emitting device 30 can have low driving voltage, long life and high external light extraction efficiency.

[0162] In some exemplary embodiments, L in Formula 22 22 This can be represented by formula 22A:

[0163] Formula 22A

[0164] L 22 ={[(m 22 -1)+0.5]×λ} / 2r 22

[0165] In Equation 22A, λ can be the maximum emission wavelength of light emitted from the second emission layer EM2 of the second emission unit EU2, and r 22 The effective refractive index represents the region between the transparent layer AT of the first electrode AN and the second emission layer EM2 of the second emission unit EU2, and m 22 It can be 2.

[0166] In addition, the light-emitting device 30 can satisfy formula 23:

[0167] Formula 23

[0168] L 23 -a 23 ≤D 23 ≤L 23 +a 23

[0169] In formula 23, D 23 This could be c) the interface between the reflective layer AR of the first electrode AN and the transparent layer AT of the first electrode AN, and d) the distance between the interface between the second emission layer EM2 of the second emission unit EU2 and the second charge transport region CT2 of the second emission unit EU2, L 23 It can be the third resonant distance of the light emitted from the second emission layer EM2 of the second emission unit EU2, and a 23It can be a real number in the range of approximately 0 nm to approximately 50 nm. This can be obtained by referring to... Figure 1 To understand a, use the description of a2 in the text. 23 .

[0170] When the light-emitting device 30 satisfies Equation 23, the second emitting layer EM2 of the second emitting unit EU2 and the reflective layer AR of the first electrode AN can be spaced apart from each other at an appropriate distance, and therefore, the light loss due to quenching caused by SPP and light loss due to waveguide (i.e., light emitted from the second emitting layer EM2 of the second emitting unit EU2) can be significantly reduced. Therefore, the light-emitting device 30 can have a high external light extraction efficiency.

[0171] In some exemplary embodiments, L in Formula 23 23 This can be represented by formula 23A:

[0172] Formula 23A

[0173] L 23 ={[(m 23 -1)+0.5]×λ} / 2r 23

[0174] In Equation 23A, λ can be the maximum emission wavelength of light emitted from the second emission layer EM2 of the second emission unit EU2, and r 23 The effective refractive index represents the region between the reflective layer AR of the first electrode AN and the second emitter layer EM2 of the second emitter unit EU2, and m 23 It can be 3.

[0175] In some exemplary embodiments, at least one of the first emitting unit EU1 and the second emitting unit EU2 in the light-emitting device 30 can emit blue light.

[0176] In some exemplary embodiments, the first emitting unit EU1 of the light-emitting device 30 can emit blue light.

[0177] exist Figure 1 In the description of the light-emitting device 10 shown, the description of the electron transport region, etc., can be applied to the first emitting unit EU1 and the second emitting unit EU2 of the light-emitting device 30.

[0178] According to one or more exemplary embodiments, an electronic device may include a light-emitting device. The electronic device may further include a thin-film transistor. In some exemplary embodiments, the electronic device may further include a thin-film transistor comprising a source electrode and a drain electrode, and a first electrode of the light-emitting device may be electrically connected to the source electrode or the drain electrode. The electronic device may further include a color filter, a color conversion layer, a touchscreen layer, a polarizing layer, or any combination thereof. The electronic device can be understood by referring to the description of the electronic device provided herein.

[0179] electronic devices

[0180] The light-emitting device 10, 20, or 30 may be included in various electronic devices. In some exemplary embodiments, the electronic device including the light-emitting device 10, 20, or 30 may be a transmitting device or an authentication device.

[0181] In addition to the light-emitting device 10, 20, or 30, the electronic device (e.g., the emitting device) may further include: i) a color filter, ii) a color conversion layer, or iii) a color filter and a color conversion layer. The color filter and / or the color conversion layer may be arranged in at least one propagation direction of the light emitted from the light-emitting device 10, 20, or 30. For example, the light emitted from the light-emitting device 10, 20, or 30 may be blue light or white light. The light-emitting device 10, 20, or 30 can be understood by referring to the description provided herein. In some embodiments, the color conversion layer may include quantum dots. In one or more embodiments, including Figure 2 or Figure 3 The electronic device of the light-emitting device 20 or 30 (i.e., tandem light-emitting device) shown may further include a color conversion layer, and the color conversion layer may include quantum dots.

[0182] An electronic device may include a first substrate. The first substrate may include a plurality of sub-pixel regions, a color filter may include a plurality of color filter regions corresponding to the plurality of sub-pixel regions, and a color conversion layer may include a plurality of color conversion regions corresponding to the plurality of sub-pixel regions.

[0183] A pixel definition layer can be located between multiple sub-pixel regions to define each sub-pixel region.

[0184] The color filter may further include a light-shielding pattern between multiple color filter areas, and the color conversion layer may further include a light-shielding pattern between multiple color conversion areas.

[0185] Multiple color filter regions (or multiple color conversion regions) may include: a first region emitting light of a first color; a second region emitting light of a second color; and / or a third region emitting light of a third color, wherein the first color light, the second color light, and / or the third color light may have different maximum emission wavelengths. In some embodiments, the first color light may be red light, the second color light may be green light, and the third color light may be blue light. In some exemplary embodiments, the multiple color filter regions (or multiple color conversion regions) may each include a quantum dot. In some exemplary embodiments, the first region may include a red quantum dot, the second region may include a green quantum dot, and the third region may not include a quantum dot. Quantum dots can be understood by referring to the description of quantum dots provided herein. The first region, the second region, and / or the third region may each further include an emitter.

[0186] In some exemplary embodiments, the light-emitting device 10, 20, or 30 can emit a first light, a first region can absorb the first light to emit light of color 1-1, a second region can absorb the first light to emit light of color 2-1, and a third region can absorb the first light to emit light of color 3-1. In this embodiment, the light of color 1-1, the light of color 2-1, and the light of color 3-1 can each have different maximum emission wavelengths. In some exemplary embodiments, the first light can be blue light, the light of color 1-1 can be red light, the light of color 2-1 can be green light, and the light of color 3-1 can be blue light.

[0187] In addition to the light-emitting devices 10, 20, or 30, the electronic device may further include a thin-film transistor. The thin-film transistor may include a source electrode, a drain electrode, and an active layer, wherein one of the source electrode and the drain electrode may be electrically connected to one of the first electrode AN and the second electrode CA of the light-emitting devices 10, 20, or 30.

[0188] Thin-film transistors may further include gate electrodes or gate insulating layers, etc.

[0189] The active layer may include crystalline silicon, amorphous silicon, organic semiconductor, or oxide semiconductor.

[0190] The electronic device may further include an encapsulation unit for sealing the light-emitting device 10, 20, or 30. The encapsulation unit may be located between the color filter and / or color conversion layer and the light-emitting device 10, 20, or 30. The encapsulation unit may allow light to pass from the light-emitting device 10, 20, or 30 to the outside while preventing air and moisture from penetrating into the light-emitting device 10, 20, or 30. The encapsulation unit may be a sealing substrate comprising a transparent glass or plastic substrate. The encapsulation unit may be a thin-film encapsulation layer comprising at least one of an organic layer and an inorganic layer. When the encapsulation unit is a thin-film encapsulation layer, the electronic device may be flexible.

[0191] In addition to color filters and / or color conversion layers, various functional layers may be arranged on the package unit depending on the purpose of the electronic device. Examples of functional layers may include a touchscreen layer or a polarization layer. The touchscreen layer may be a resistive touchscreen layer, a capacitive touchscreen layer, or an infrared beam touchscreen layer. The authentication device may be a biometric authentication device that identifies an individual based on biometric information (e.g., fingertip or pupil).

[0192] In addition to the light-emitting devices 10, 20 or 30 described above, the authentication device may further include a biometric information collection unit.

[0193] Electronic devices can be used for various displays, light sources, lighting equipment, personal computers (e.g., mobile personal computers), cellular phones, digital cameras, electronic notebooks, electronic dictionaries, video game consoles, medical devices (e.g., electronic thermometers, blood pressure monitors, blood glucose meters, pulse measuring devices, pulse wave measuring devices, electrocardiogram recorders, ultrasound diagnostic devices, endoscopic display devices), fish finders, various measuring devices, instruments (e.g., instruments for automobiles, airplanes, and ships), and projectors.

[0194] Table Description

[0195] OLED B, OLED B-1 and OLED B-2 are each manufactured according to the structures shown in Table 1.

[0196] Table 1

[0197]

[0198]

[0199] Table 2

[0200]

[0201] 1 The effective refractive index of the hole transport region and the ITO layer region is 2.0.

[0202] Referring to the results in Tables 1 and 2, it was found that OLED B satisfies Formula 1 and Formula 2, and that OLED B-1 and B-2 do not each satisfy at least one of Formula 1 and Formula 2.

[0203] Using the Keithley Source Measurement Unit SMU 236 and Luminometer PR650, at 1,000 cd / m 2 The driving voltage (V), luminous efficacy (cd / A), and lifetime (T) of OLED B, OLED B-1, and OLED B-2 were measured. 90 The results are shown in Table 3. Lifetime (T) 90The luminous efficacy and lifetime in Table 3 indicate the time (in hours) it takes for the brightness of each organic light-emitting device to decay to 90% of its initial brightness. The luminous efficacy and lifetime in Table 3 are relative values.

[0204] Table 3

[0205]

[0206] Referring to the results in Table 3, it was found that OLED B has lower driving voltage, higher luminous efficiency, and longer lifetime compared to OLED B-1 and OLED B-2.

[0207] Subsequently, OLED G, OLED G-1 and OLED G-2 were each manufactured according to the structures shown in Table 4.

[0208] Table 4

[0209]

[0210]

[0211] Table 5

[0212]

[0213] 2 The effective refractive index of the hole transport region and the ITO layer region is 2.0.

[0214] Referring to the results in Tables 4 and 5, it was found that OLED G satisfies Formula 1 and Formula 2, and that OLED G-1 and G-2 do not each satisfy at least one of Formula 1 and Formula 2.

[0215] Using the Keithley Source Measurement Unit SMU 236 and Luminometer PR650, a value of 7,000 cd / m² was achieved. 2 The driving voltage (V), luminous efficacy (cd / A), and lifetime (T) of OLED G, OLED G-1, and OLED G-2 were measured. 90 The results are shown in Table 6. Lifetime (T) 90 The luminous efficacy and lifetime in Table 6 indicate the time (in hours) it takes for the brightness of each organic light-emitting device to decay to 90% of its initial brightness. The luminous efficacy and lifetime in Table 6 are relative values.

[0216] Table 6

[0217]

[0218]

[0219] Referring to the results in Table 6, it was found that OLED G has lower driving voltage, higher luminous efficiency, and longer lifetime compared to OLED G-1 and OLED G-2.

[0220] Subsequently, OLED R, OLED R-1 and OLED R-2 were each manufactured according to the structures shown in Table 7.

[0221] Table 7

[0222]

[0223] Table 8

[0224]

[0225] 3 The effective refractive index of the hole transport region and the ITO layer region is 2.0.

[0226] Referring to the results in Tables 7 and 8, it was found that OLED G satisfies Formula 1 and Formula 2, and that OLED G-1 and G-2 do not each satisfy at least one of Formula 1 and Formula 2.

[0227] Using the Keithley Source Measurement Unit SMU 236 and Luminometer PR650, the result was 3,500 cd / m². 2 The driving voltage (V), luminous efficiency (cd / A), and lifetime (T) of OLED R, OLED R-1, and OLED R-2 were measured. 90 The results are shown in Table 9. Lifetime (T) 90 The luminous efficacy and lifetime in Table 9 indicate the time (in hours) it takes for the brightness of each organic light-emitting device to decay to 90% of its initial brightness. The luminous efficacy and lifetime in Table 9 are relative values.

[0228] Table 9

[0229]

[0230] Referring to the results in Table 9, it was found that OLED R has lower driving voltage, higher luminous efficiency, and longer lifetime compared to OLED R-1 and OLED R-2.

[0231] It is evident from the preceding description that light-emitting devices can have low driving voltage, high luminous efficiency, and long lifespan, and therefore, high-quality electronic devices can be manufactured by using light-emitting devices.

[0232] While specific exemplary embodiments have been described herein, other embodiments and modifications will be apparent from this description. Therefore, the inventive concept is not limited to such embodiments, but is limited to the broader scope of the appended claims and various obvious modifications and equivalent arrangements that will be apparent to those skilled in the art.

Claims

1. A light-emitting device, comprising: First electrode; The second electrode faces the first electrode; An emission layer is located between the first electrode and the second electrode; as well as A charge transport region is located between the emitter layer and the first electrode. in: Light emitted from the emitting layer is transmitted to the outside through the second electrode; The first electrode is a reflective electrode; The first electrode includes a transparent layer and a reflective layer; and The following formulas 1 and 2 are satisfied: Formula 1 L1-a1≤D1≤L1+a1 In Formula 1, D1 represents the distance between i) the interface between the transparent layer and the charge transport region of the first electrode and ii) the interface between the emitting layer and the charge transport region, L1 represents the first resonant distance of the light emitted from the emitting layer, and a1 is a real number in the range of 0 nanometers (nm) to 50 nm. Formula 2 L2-a2≤D2≤L2+a2 In Formula 2, D2 represents the distance between a) the interface between the reflective layer and the transparent layer of the first electrode and b) the interface between the emitting layer and the charge transport region, L2 represents the second resonant distance of the light emitted from the emitting layer, and a2 is a real number in the range of 0 nm to 50 nm. In Equation 1, L1 is represented by Equation 1A: Formula 1A L1={[(m1-1)+0.5]×λ} / 2r1 In Formula 1A, λ represents the maximum emission wavelength of the light emitted from the emitting layer, r1 represents the effective refractive index of the region located between the transparent layer and the emitting layer of the first electrode, and m1 is 1. In formula 2, L2 is represented by formula 2A: Formula 2A L2={[(m2-1)+0.5]×λ} / 2r2 In Formula 2A, λ represents the maximum emission wavelength of the light emitted from the emitting layer, r2 represents the effective refractive index of the region located between the reflective layer and the emitting layer of the first electrode, and m2 is 2. Formula 4 is satisfied as follows: Formula 4 n1-n2≥0.1 In Formula 4, n1 is the refractive index of the transparent layer of the first electrode, and n2 is the refractive index of the layer in the charge transport region that is in direct contact with the transparent layer of the first electrode.

2. The light-emitting device according to claim 1, wherein, The light emitted from the emitting layer is blue light having a maximum emission wavelength in the range of 440 nm to 480 nm, green light having a maximum emission wavelength in the range of 510 nm to 550 nm, or red light having a maximum emission wavelength in the range of 610 nm to 640 nm.

3. The light-emitting device according to claim 1, wherein, r1 is in the range of 1.5 to 2.

1.

4. The light-emitting device according to claim 1, wherein, r2 is in the range of 1.6 to 2.

5.

5. The light-emitting device according to claim 1, wherein, The light emitted from the emitting layer is blue light, and D1 in Formula 1 is in the range of 10 nm to 60 nm.

6. The light-emitting device according to claim 1, wherein, The light emitted from the emitting layer is blue light, and D2 in Formula 2 is in the range of 50 nm to 180 nm.

7. The light-emitting device according to claim 1, wherein, The light emitted from the emission layer is green light, and D1 in Formula 1 is in the range of 40 nm to 95 nm.

8. The light-emitting device according to claim 1, wherein, The light emitted from the emission layer is green light, and D2 in Formula 2 is in the range of 80 nm to 215 nm.

9. The light-emitting device according to claim 1, wherein, The light emitted from the emitting layer is red light, and D1 in Formula 1 is in the range of 60 nm to 145 nm.

10. The light-emitting device according to claim 1, wherein, The light emitted from the emission layer is red light, and D2 in Formula 2 is in the range of 130 nm to 225 nm.

11. The light-emitting device according to claim 1, wherein, The first electrode is a conductive layer.

12. The light-emitting device according to claim 1, wherein, The transparent layer of the first electrode is a metal oxide layer, and the reflective layer of the first electrode is a metal layer.

13. A light-emitting device, comprising: First electrode; The second electrode faces the first electrode; A number of emitter units, numbered x, are stacked between the first electrode and the second electrode; as well as x-1 charge generation layers are located between every two adjacent emitter units in a number x of the emitter units, each of the x-1 charge generation layers comprising an n-type charge generation layer and a p-type charge generation layer. in: x is an integer of 2 or greater; Each of the x number of emission units includes a charge transport region and an emission layer sequentially stacked above the first electrode; Light emitted from the x number of emission units is transmitted to the outside through the second electrode; The first electrode is a reflective electrode; The first electrode includes a transparent layer and a reflective layer; and The following formulas y and y+1 are satisfied: Formula y L y -a y ≤D y ≤L y +a y In formula y, D y L represents the distance between i) the interface between the transparent layer of the first electrode and the charge transport region of the first emitting unit, and ii) the distance between the emitting layer of the y-th emitting unit in a number of x emitting units and the interface between the charge transport region of the y-th emitting unit in a number of x emitting units. y Let a be the y-th resonant distance of the light emitted from the emission layer of the y-th emission unit among the x-th emission units, and a y For real numbers in the range of 0nm to 50nm, Formula y+1 L y+1 -a y+1 ≤D y+1 ≤L y+1 +a y+1 In the formula y+1, D y+1 L is the distance between a) the interface between the reflective layer and the transparent layer of the first electrode and b) the distance between the emission layer of the y-th emission unit in the x-th number of emission units and the interface between the charge transport region of the y-th emission unit in the x-th number of emission units. y+1 Let a be the (y+1)th resonant distance of the light emitted from the emission layer of the yth emission unit among the x number of emission units, and a y+1 For real numbers in the range of 0nm to 50nm, Where L in formula y y Represented by formula 1YA: Formula 1YA L y ={[(m 1y -1)+0.5]×λ} / 2r y In formula 1YA, λ represents the maximum emission wavelength of the light emitted from the emission layer of the y-th emission unit, and r y The effective refractive index represents the region located between the transparent layer of the first electrode and the emission layer of the y-th emission unit, and m 1y =1, In the formula y+1, L y+1 Represented by formula 2YA: Formula 2YA L y+1 ={[(m 2y -1)+0.5]×λ} / 2r y+1 In formula 2YA, λ represents the maximum emission wavelength of the light emitted from the emission layer of the y-th emission unit, and r y+1 The effective refractive index represents the region located between the reflective layer of the first electrode and the emission layer of the y-th emission unit, and m 2y It is 2, and Formula 4 is satisfied as follows: Formula 4 n1-n2≥0.1 In Formula 4, n1 is the refractive index of the transparent layer of the first electrode, and n2 is the refractive index of the layer in the charge transport region that is in direct contact with the transparent layer of the first electrode.

14. The light-emitting device according to claim 13, wherein, x is 2.

15. A light-emitting device, comprising: First electrode; The second electrode faces the first electrode; The first transmitting unit is located between the first electrode and the second electrode; The second transmitting unit is located between the first transmitting unit and the second electrode; as well as A charge generation layer, located between the first emitting unit and the second emitting unit, includes an n-type charge generation layer and a p-type charge generation layer. in: The first emitting unit includes a first charge transport region and a first emitting layer sequentially stacked on the first electrode; The second emitting unit includes a second charge transport region and a second emitting layer sequentially stacked on the charge generation layer; Light emitted from the first emitting unit and the second emitting unit is transmitted to the outside through the second electrode; The first electrode is a reflective electrode; The first electrode includes a transparent layer and a reflective layer; and Formulas 11, 12, 22, and 23 are satisfied as follows: Formula 11 L 11 -a 11 ≤D 11 ≤L 11 +a 11 In Formula 11, D 11 L represents the distance between i) the interface between the transparent layer of the first electrode and the first charge transport region of the first emitting unit, and ii) the interface between the first emitting layer of the first emitting unit and the first charge transport region of the first emitting unit. 11 The first resonant distance of the light emitted from the first emitting layer of the first emitting unit, and a 11 For real numbers in the range of 0nm to 50nm; Formula 12 L 12 -a 12 ≤D 12 ≤L 12 +a 12 In formula 12, D 12 L is the distance between a) the interface between the reflective layer and the transparent layer of the first electrode and b) the interface between the first emitting layer and the first charge transport region of the first emitting unit. 12 The second resonant distance of the light emitted from the first emitting layer of the first emitting unit, and a 12 For real numbers in the range of 0nm to 50nm; Formula 22 L 22 -a 22 ≤D 22 ≤L 22 +a 22 In formula 22, D 22 For iii) the interface between the transparent layer of the first electrode and the first charge transport region of the first emitting unit and iv) the distance between the second emitting layer of the second emitting unit and the second charge transport region of the second emitting unit, L 22 The second resonant distance of the light emitted from the second emitting layer of the second emitting unit, and a 22 Let be a real number in the range of 0 nm to 50 nm; and Formula 23 L 23 -a 23 ≤D 23 ≤L 23 +a 23 In formula 23, D 23 L is the distance between c) the interface between the reflective layer and the transparent layer of the first electrode and d) the interface between the second emitting layer and the second charge transport region of the second emitting unit. 23 The third resonant distance of the light emitted from the second emitting layer of the second emitting unit, and a 23 For real numbers in the range of 0nm to 50nm, In formula 11, L 11 Equation 11A represents: Formula 11A L 11 ={[(m 11 -1)+0.5]×λ} / 2r 11 In Formula 11A, λ represents the maximum emission wavelength of the light emitted from the first emitting layer, and r 11 The effective refractive index represents the region located between the transparent layer and the first emission layer of the first electrode, and m 11 =1, In formula 12, L 12 Equation 12A represents: Formula 12A L 12 ={[(m 12 -1)+0.5]×λ} / 2r 12 In Formula 12A, λ represents the maximum emission wavelength of the light emitted from the first emitting layer, and r 12 The effective refractive index represents the region located between the reflective layer and the emissive layer of the first electrode, and m 12 It is 2. In formula 22, L 22 Equation 22A represents: Formula 22A L 22 ={[(m 22 -1)+0.5]×λ} / 2r 22 In formula 22A, λ represents the maximum emission wavelength of the light emitted from the second emitting layer, and r 22 This represents the effective refractive index of the region located between the transparent layer and the second emission layer of the first electrode, and m 22 It is 2. In formula 23, L 23 Equation 23A represents: Formula 23A L 23 ={[(m 23 -1)+0.5]×λ} / 2r 23 In formula 23A, λ represents the maximum emission wavelength of the light emitted from the second emitting layer, and r 23 The effective refractive index represents the region located between the reflective layer and the second emitting layer of the first electrode, and m 23 The value is 3.

16. An electronic device comprising the light-emitting device according to claim 1.

Images