Light Emitting Display Device

Abstract

The light-emitting display device of the present invention can improve image quality by applying a configuration of an auxiliary color conversion unit in which a color conversion layer with different transmission characteristics is superimposed on the non-light-emitting part of a subpixel, thereby improving luminance efficiency and making the color purity uniform according to current density.

Description

Technology Field

[0001] The present invention relates to a display device, and more specifically, to a light-emitting display device that improves image quality by improving luminance efficiency through the configuration of an auxiliary color conversion layer in a non-light-emitting part and ensuring uniform color purity regardless of current density. Background Technology

[0002] With the recent entry into the full-scale information age, the field of displays that visually represent electrical information signals has been rapidly developing. In response to this, various display devices with excellent performance characteristics such as thinness, lightness, and low power consumption have been developed and are rapidly replacing existing Cathode Ray Tubes (CRTs).

[0003] Among display devices, light-emitting display devices are being considered as competitive applications for their ability to achieve device compactness and vivid color display without requiring a separate light source.

[0004] Meanwhile, in a light-emitting display device, a light-emitting element having a light-emitting layer is placed between electrodes facing each other. In forming the light-emitting element, a method of forming it as a tandem element is mainly used in large-area display devices to improve process convenience and yield. The problem to be solved

[0005] Meanwhile, since tandem elements have different light-emitting layers overlapping adjacent subpixels, even when only a specific subpixel is turned on, it may be affected by the lateral leakage current of adjacent subpixels. In particular, the change in color coordinates of the red subpixel at low current density is greater than the change in color coordinates at high current density, which means that it is difficult for the red subpixel to display a normal red color under low current density conditions.

[0006] The light-emitting display device of the present invention is intended to solve the aforementioned problems and relates to a light-emitting display device that improves image quality by applying an auxiliary color conversion layer configuration to the non-light-emitting part of a subpixel to improve luminance efficiency and uniformly maintaining color purity according to current density. means of solving the problem

[0007] The light-emitting display device of the present invention can improve image quality by improving luminance efficiency through the configuration of an auxiliary color conversion layer in the non-light-emitting part and making the color purity uniform according to current density.

[0008] A light-emitting display device according to an embodiment of the present invention comprises: a substrate including a first subpixel, a second subpixel, a third subpixel, and a fourth subpixel, each having a light-emitting portion and a non-light-emitting portion surrounding the light-emitting portion; a red conversion layer, a green conversion layer, and a blue conversion layer provided on the substrate, respectively, corresponding to the light-emitting portions of the first subpixel, the second subpixel, and the third subpixel; a first auxiliary color conversion unit having a first auxiliary color conversion layer that transmits red light and a second auxiliary color conversion layer that transmits light with a shorter wavelength than the red light, stacked on the non-light-emitting portion of the first subpixel; a flattening layer covering the red conversion layer, the green conversion layer, the blue conversion layer, and the first auxiliary color conversion unit; and a first stack provided on the flattening layer across the first to fourth subpixels, comprising a first electrode, a second electrode facing each other, and a first blue light-emitting layer between the first and second electrodes. It may include a light-emitting element having a second stack including a red light-emitting layer and a green light-emitting layer, and a first charge-generating layer between the first and second stacks. Effects of the invention

[0009] The light-emitting display device of the present invention has the following effects.

[0010] The light-emitting display device of the present invention can improve the color purity of red by blocking colors other than red that cause leakage, in a structure in which a different type of light-emitting part of a light-emitting element is provided with a high-efficiency green light-emitting layer in addition to a red light-emitting layer to improve luminance efficiency, and by applying an auxiliary color conversion part having a structure in which a red conversion layer and a blue conversion layer are laminated on the outer side of the red light-emitting part at the bottom of the light-emitting element. In particular, through the dual-structured auxiliary color conversion part, color deviation can be prevented at low and high current densities, enabling uniform color expression regardless of current density and thereby improving image quality.

[0011] In addition, the light-emitting display device of the present invention can further enhance the effect of improving the image quality of the display device and preventing the degradation of red color purity caused by lateral leakage by further providing a double-structured auxiliary color conversion unit on the outer side of the white light-emitting unit. Brief explanation of the drawing

[0012] FIG. 1 is a plan view of a light-emitting display device according to a first embodiment of the present invention. FIG. 2 is a cross-sectional view of a light-emitting display device according to a first embodiment of the present invention. FIG. 3 is a plan view of a light-emitting display device according to a second embodiment of the present invention. FIG. 4 is a cross-sectional view of a light-emitting display device according to a second embodiment of the present invention. FIG. 5 is a cross-sectional view schematically showing a light-emitting element of the light-emitting display device of the present invention. FIG. 6 is a cross-sectional view specifically showing the stack structure of a light-emitting element of the light-emitting display device of the present invention. FIGS. 7a and FIGS. 7b are cross-sectional views showing Device A and Device B. Figure 8 is a graph showing the color gamut when Device A and Device B are driven at a low current density. Figures 9a and 9b are graphs showing the intensity according to wavelength when driving Device A at low and high current densities. Figures 10a and 10b are graphs showing the intensity according to wavelength when driving Device B at low and high current densities. Figure 11 is a graph comparing the red intensity of Device A and Device B according to current density. FIGS. 12a to 12f are cross-sectional views according to the first to sixth experimental examples. Figure 13 is a graph showing CIEx and CIEy of the first experimental example. FIGS. 14a to 14c are graphs showing CIEx according to the 2nd to 4th experimental examples. Figure 15a is a graph comparing CIEx according to the 2nd, 5th, and 6th experimental examples. FIG. 15b is a graph comparing CIEx according to the first experimental example and the sixth experimental example. Figure 16 is a graph comparing CIEx when a single red conversion layer (Ex2a), a stacked structure of a red conversion layer and a green conversion layer (Ex5a), and a stacked structure of a red conversion layer and a blue conversion layer (Ex6a) are applied to the non-emissive part of Device A. Figure 17 is a graph comparing CIEx when a single red conversion layer (Ex2), a stacked structure of a red conversion layer and a green conversion layer (Ex5), and a stacked structure of a red conversion layer and a blue conversion layer (Ex6) are applied to the non-emissive part of Device B. Specific details for implementing the invention

[0013] Hereinafter, preferred embodiments of the present invention will be described with reference to the attached drawings. Throughout the specification, identical reference numbers denote substantially identical components. In the following description, if it is determined that a detailed description of a technology or configuration related to the present invention could unnecessarily obscure the essence of the invention, such detailed description is omitted. Furthermore, the component names used in the following description have been selected for ease of drafting the specification and may differ from the actual product part names.

[0014] Shapes, sizes, ratios, angles, numbers, etc. disclosed in the drawings for describing various embodiments of the present invention are exemplary, and therefore the present invention is not limited to the matters depicted in the drawings. Throughout this specification, the same reference numerals refer to the same components. Furthermore, in describing the present invention, if it is determined that a detailed description of related prior art may unnecessarily obscure the essence of the present invention, such detailed description is omitted. Where terms such as "includes," "has," or "is made up" are used in this specification, other parts may be added unless "only" is used. Where a component is expressed in the singular, it includes cases where it is included in the plural unless specifically stated otherwise.

[0015] In interpreting the components included in various embodiments of the present invention, they are interpreted to include an error range even without separate explicit description.

[0016] In describing various embodiments of the present invention, when describing positional relationships, for example, when the positional relationship between two parts is described using expressions such as 'on', 'on the upper part', 'on the lower part', 'next to', etc., unless 'immediately' or 'directly' is used, one or more other parts may be located between the two parts.

[0017] In describing various embodiments of the present invention, when describing temporal relationships, for example, when describing temporal sequence relationships using 'after', 'following', 'next', 'before', etc., cases that are not continuous may be included unless 'immediately' or 'directly' is used.

[0018] In describing various embodiments of the present invention, terms such as 'first~', 'second~', etc. may be used to describe various components, but these terms are used merely to distinguish between identical or similar components. Accordingly, unless otherwise stated, a component modified by 'first~' in this specification may be identical to a component modified by 'second~' within the technical scope of the present invention.

[0019] Each feature within various embodiments of the present invention may be combined or combined with one another, either partially or wholly, and may technically enable various interlocking and operation. Each of the various embodiments may be implemented independently of one another or may be implemented together in an associated relationship.

[0020] In this specification, "doped" means that a material having different physical properties (e.g., N-type and P-type, organic and inorganic materials) is added to a material that constitutes the majority by weight of a layer in an amount of less than 30% by weight. In other words, a "doped" layer refers to a layer in which the host material and the dopant material of a layer can be distinguished by considering their specific gravity by weight. Furthermore, "undoped" refers to all cases other than those corresponding to "doped." For example, if a layer is composed of a single material or is composed of a mixture of materials with identical or similar properties, that layer is included in the "undoped" layer. For example, if at least one of the materials constituting a layer is P-type and not all of the materials constituting the layer are N-type, that layer is included in the "undoped" layer. For example, if at least one of the materials constituting a layer is an organic material and not all of the materials constituting the layer are inorganic materials, that layer is included in the 'undoped' layer. For example, if all of the materials constituting a layer are organic materials, and at least one of the materials constituting the layer is N-type and at least one of the other is P-type, the layer is included in the 'doped' layer if the weight ratio of the N-type material is less than 30% or the weight ratio of the P-type material is less than 30%.

[0021] Meanwhile, in this specification, the term EL (electroluminescence) spectrum is calculated as the product of (1) a PL (photoluminescence) spectrum that reflects the unique characteristics of a light-emitting material, such as a dopant material or a host material included in an organic light-emitting layer, and (2) an out-coupling emittance spectrum curve determined by the structure and optical characteristics of an organic light-emitting device, such as the thickness of an electron transport layer.

[0022] FIG. 1 is a plan view of a light-emitting display device according to a first embodiment of the present invention, and FIG. 2 is a cross-sectional view of a light-emitting display device according to a first embodiment of the present invention.

[0023] As shown in FIG. 1 and FIG. 2, a light-emitting display device according to a first embodiment of the present invention comprises: a substrate (100) including a first subpixel (R_SP), a second subpixel (G_SP), a third subpixel (B_SP), and a fourth subpixel (W_SP), each having a light-emitting part (EM) and a non-light-emitting part (NEM) surrounding the light-emitting part; a red conversion layer (RCF), a green conversion layer (GCF), and a blue conversion layer (BCF) respectively provided on the substrate in correspondence with the light-emitting parts (REM, GEM, BEM) of the first subpixel (R_SP), the second subpixel (G_SP), and the third subpixel (B_SP); and a first auxiliary color conversion layer (ARCF) that transmits red light and a second auxiliary color conversion layer (ABCF) that transmits light of a shorter wavelength than the red light, which are laminated on the non-light-emitting part (NEM) of the first subpixel (R_SP). It comprises a color conversion unit (OCF1, OCF2), a flattening layer (108) covering the red conversion layer (RCF), the green conversion layer (GCF), and the blue conversion layer (BCF), and the first auxiliary color conversion unit (OCF1, OCF2), and a light-emitting element (OLED) provided on the first to fourth subpixels (R_SP, G_SP, B_SP, W_SP) on the flattening layer.

[0024] Here, the light-emitting element (OLED) includes a first electrode (110), a second electrode (200) facing each other, and an organic stack (OS) having multiple stacks between the first and second electrodes (110, 200). The organic stack (OS) may include a first stack (S1) having a first blue light-emitting layer (BEML1 in FIG. 6) as a minimum configuration, a second stack (S2) having a red light-emitting layer (see 141 in FIG. 6) and a green light-emitting layer (see 143 in FIG. 6), and a first charge generating layer (see 150 in FIG. 6) between the first and second stacks.

[0025] In the light-emitting element (OLED), the first electrode (110) is formed separately from each other so that it functions independently in each subpixel (R_SP, G_SP, B_SP, W_SP). In the tandem device, the remaining components of the light-emitting element (OLED), namely the organic stack (OS) and the second electrode (200), can be formed integrally without interruption on the plane of each of the multiple subpixels (R_SP, G_SP, B_SP, W_SP). Therefore, in forming the organic stack (OS) and the second electrode (200), the process can proceed without a metal mask requiring fine openings, thereby resolving problems caused by sagging of the metal mask or the burden required for manufacturing the metal mask.

[0026] FIG. 1 shows first to fourth subpixels (R_SP, G_SP, B_SP, W_SP) emitting different colors among a plurality of subpixels provided on a substrate (100), and such first to fourth subpixels (R_SP, G_SP, B_SP, W_SP) may be arranged continuously on the substrate (100). The illustrated example shows an example in which the first to fourth subpixels (R_SP, G_SP, B_SP, W_SP) are arranged in a stripe shape, but is not limited thereto. For example, the four subpixels emitting different colors may be divided into two pairs and arranged side by side in a horizontal or vertical direction, such as the first and second subpixels being arranged in one row and the third and fourth subpixels being arranged in the next row. Alternatively, other subpixels may be divided and arranged within a rhombus shape.

[0027] In the example of FIG. 1, the first subpixel (R_SP), the fourth subpixel (W_SP), the third subpixel (B_SP), and the second subpixel (G_SP) are shown in order from left to right. For the purpose of explaining the invention, only the vertical wiring separating the subpixels is shown, and the remaining wiring is omitted.

[0028] The shape of the subpixels may vary depending on the shape of the intersecting wires. Additionally, the subpixels may have different shapes depending on the optimal luminous efficiency required by the device. Although FIG. 1 shows that the first to fourth subpixels (R_SP, G_SP, B_SP, W_SP) each have different shapes, this is not limited to this, and the size and area of ​​the subpixels may be the same. In the example illustrated in FIG. 1, four adjacent subpixels are shown in a roughly stripe shape, and the horizontal wires are omitted. A data line (DL) that supplies a data voltage to each subpixel is provided in correspondence, and a driving power voltage line (VDDL) that supplies a driving power voltage signal to two adjacent subpixels is provided. A scan line that applies a scan signal for each row may be provided intersecting the data line (DL) and the driving power voltage line (VDDL), and a switching transistor that determines the turn-on of each subpixel may be further provided at the intersection with the source electrode (drain electrode) protruding from each data line (DL). Each subpixel is equipped with a driving transistor connected to a driving power voltage line (VDDL), and the transistor (TFT) shown in FIG. 2 may be the driving transistor. In the example shown in FIG. 1, two data lines are arranged between the first and fourth subpixels (R_SP, W_SP), and two data lines are arranged between the second and third subpixels (G_SP, B_SP) to supply data voltage to both subpixels. This is not limited to this, and data lines may be provided at the same location corresponding to each subpixel.

[0029] The light-emitting elements (OLEDs) provided in the first to fourth subpixels (R_SP, G_SP, B_SP, W_SP) emit white light, and the light-emitting portions (EM) of the first to third subpixels (R_SP, G_SP, B_SP) are each provided with a red conversion layer (RCF), a green conversion layer (GCF), and a blue conversion layer (BCF) to express the color of each subpixel. The fourth subpixel (W_SP) does not have a color conversion layer and can emit light emitted from the light-emitting element (OLED) as is.

[0030] Depending on the reflectivity and transmittance of the first and second electrodes (110, 200), the light emitted from the organic stack (OS) can have a different direction of emission. For example, when the first electrode (110) is transparent and the second electrode (200) is reflective, the light can be emitted downwards as shown in FIG. 2, and when the first electrode (110) is reflective and the second electrode (200) is transparent, the light can be transmitted upwards. In some cases, if one of the first and second electrodes (110, 200) is transparent and the other is transparent or semi-transparent, the light can be transmitted in both directions. Either one of the first electrode (110) and the second electrode (200) may be a transparent oxide alloy such as ITO, IZO, ITZO, and the other may be a metal or metal alloy comprising at least one of silver (Ag), magnesium (Mg), aluminum (Al), ytterbium (Yb), and strontium (Sr).

[0031] In the case of a light-emitting display device using a bottom-emitting method or a transparent display device, circuits such as wiring and transistors are avoided in the area corresponding to the emission side, and as shown in FIG. 1, it can be seen that the light-emitting parts (REM, WEM, BEM, GEM) of each subpixel have different shapes by avoiding wiring and transistors.

[0032] The red conversion layer (RCF), green conversion layer (GCF), and blue conversion layer (BCF) are a type of color filter that transmits light of a broad spectrum in the visible light range into light in the red, green, and blue ranges, respectively, limited to a specific color range. The red conversion layer (RCF) and the first auxiliary color conversion layer (ARCF) can transmit red light and block green and blue light, the green conversion layer (GCF) can transmit green light and block red and blue light, and the blue conversion layer (BCF) and the second auxiliary color conversion layer (ABCF) can transmit blue light and block red and green light. The red conversion layer (RCF), green conversion layer (GCF), and blue conversion layer (BCF) may include pigments or dyes to perform the function of selectively transmitting light.

[0033] A light-emitting display device according to the first embodiment of the present invention has a first auxiliary color conversion unit (OCF1, OCF2) in the non-light-emitting portion of a first subpixel (R_SP), and the first auxiliary color conversion unit (OCF1, OCF2) may be provided along the upper and lower outlines adjacent to the upper and lower boundaries of a red light-emitting portion (REM). The first auxiliary color conversion unit (OCF1, OCF2) is formed by stacking a plurality of color conversion layers. As shown in FIG. 2, the first auxiliary color conversion unit (OCF1, OCF2) may include a first auxiliary color conversion layer (ARCF) identical to the red conversion layer (RCF) provided in the light-emitting portion (EM) of the first subpixel (R_SP) where the first auxiliary color conversion unit (OCF1, OCF2) is formed, and a second auxiliary color conversion layer (ABCF) that transmits a color different from the first auxiliary color conversion layer (ARCF).

[0034] The reason the first auxiliary color conversion unit (OCF1, OCF2) is provided around the red light emitting unit (REM) is to adjust the color purity of the light emitted from the red light emitting unit (REM) to be constant regardless of current density. That is, the first auxiliary color conversion unit (OCF1, OCF2) provided around the red light emitting unit (REM) blocks the light emitted from around the red light emitting unit (REM) through its selective transmission function, thereby preventing light of a different color from the red light emitting unit (REM) from being emitted.

[0035] In particular, among the light-emitting elements (OLEDs), an organic stack (OS) that emits light is provided in common to all subpixels, and light emission is not only in the up and down direction but can also proceed radially through resonance and reflection between the first and second electrodes (110, 200), and light from the non-emissive portion (NEM) can also proceed sideways and affect the adjacent light-emitting portion (EM). In particular, in a structure in which a color conversion layer is provided only in the light-emitting portion, especially in the red light-emitting portion (REM), there is a tendency for color purity to decrease when driven at a low current density, so the light-emitting display device of the present invention is provided with a first auxiliary color conversion portion (OCF1, OCF2) to block light other than red in the red light-emitting portion (REM).

[0036] Here, the first auxiliary color conversion unit (OCF1, OCF2) is provided with a second auxiliary color conversion layer (ABCF) that transmits other colors in addition to the first auxiliary color conversion layer (ARCF) that selectively transmits red. This is done to consider the function of blocking other colors rather than the transmission function of the second auxiliary color conversion layer (ABCF) itself, and the filter function of colors blocked by both the first and second auxiliary color conversion layers (ARCF, ABCF) is enhanced by the stacking of the first and second auxiliary color conversion layers (ARCF, ABCF). For example, the second auxiliary color conversion layer (ABCF) has a large difference in the transmission light region compared to the first auxiliary color conversion layer (ARCF), and it is preferable that it can transmit light of short wavelengths of 100 nm to 220 nm, which is greater than the transmission region of the first auxiliary color conversion layer (ARCF). In this case, the second auxiliary color conversion layer (ABCF) can be formed from the same material as the blue conversion layer (BCF) provided in the blue light-emitting part (BEM). At this time, by double stacking the first and second auxiliary color conversion layers (ARCF, ABCF), the green light emitted relatively strongly from the light-emitting element (OLED) can be double-blocked, thereby preventing the color purity of the red light-emitting part from being affected by lateral leakage of strong green light. Depending on the case, the first auxiliary color conversion part (OCF1, OCF2) can be formed by additionally overlapping a third auxiliary color conversion layer (AGCF) capable of transmitting green light in addition to the first and second auxiliary color conversion layers (ARCF, ABCF), and the same effect of blocking leakage light can be expected.

[0037] A bank (119) is further provided in the non-emissive portion (NEM) of the first to fourth subpixels (R_SP, G_SP, B_SP, W_SP). Since the first auxiliary color conversion unit (OCF1, OCF2) is provided in the non-emissive portion, the bank (119) overlaps with the first auxiliary color conversion unit (OCF1, OCF2). Since the first auxiliary color conversion unit (OCF1, OCF2) is configured with a stacked plurality of color conversion layers, it reduces transmittance when provided in the emitting portion, so it is provided outside the red emitting portion (REM).

[0038] Additionally, as shown in FIG. 2, each of the first to fourth subpixels' non-emissive parts (NEM) further includes a thin-film transistor (TFT). At least in the first subpixel (R_SP) that emits red, the first auxiliary color conversion part (OCF1, OCF2) is positioned so as not to overlap with the thin-film transistor, thereby preventing the degradation of the color purity of red due to lateral leakage light in the area of ​​the non-emissive part (NEM) where the thin-film transistor is not located, and enabling a red light emission display having uniform color characteristics regardless of current density.

[0039] Meanwhile, 110a, which is not described in FIG. 1, is formed on the same layer as the first electrode (110) as a first electrode dummy pattern and can be used as a means of connection between the second electrode (200) and auxiliary wiring (not shown), or as another circuit configuration placed in a storage capacitor or a non-light-emitting part. In some cases, the first electrode dummy pattern (110a) may be omitted.

[0040] The thin-film transistor (TFT) of FIG. 2 includes, for example, a gate electrode (102), a semiconductor layer (104), and a source electrode (106a) and a drain electrode (106b) connected to both sides of the semiconductor layer (104) on a substrate (100).

[0041] A gate insulating film (103) is provided between the gate electrode (102) and the semiconductor layer (104).

[0042] The semiconductor layer (104) may be composed of, for example, amorphous silicon, polycrystalline silicon, an oxide semiconductor, or a combination of two or more of the listed materials. For example, if the semiconductor layer (104) is an oxide semiconductor, an etch stopper (105) may be further provided in direct contact with the semiconductor layer (104) to prevent damage to the channel portion of the semiconductor layer (104).

[0043] In some cases, the gate electrode (102), source electrode (106a), and drain electrode (106b) may be provided on the same layer.

[0044] Additionally, the drain electrode (106b) of the thin film transistor (TFT) can be connected to the first electrode (110) and the contact hole (CT) region provided within the protective film (107) and the planarization layer (108).

[0045] The above protective film (107) is primarily provided to protect the thin-film transistor (TFT), and the color conversion layer (RCF, GCF, BCF) described above may be provided on the upper surface corresponding to each light-emitting part (REM, GEM, BEM).

[0046] A red conversion layer (RCF), a green conversion layer (GCF), and a blue conversion layer (BCF) are separately provided in the remaining subpixels (R_SP, G_SP, B_SP) excluding the fourth subpixel (W_SP), so that white light emitted through the first electrode (110) passes through each wavelength of the respective range.

[0047] Light emitted from the light-emitting element (OLED) is emitted from the first to third subpixels (R_SP, G_P, B_SP) to the bottom of the substrate (100) through the first electrode (110), planarization layer (108), color conversion layer (RCF, GCF, BCF), protective film (107), and gate insulating film (103). Since the fourth subpixel (W_SP) does not pass through the color conversion layer among the films through which the light passes, it can be emitted while maintaining broad wavelength characteristics of the white spectrum.

[0048] Meanwhile, the first auxiliary color conversion unit (OCF1, OCF2) provided in the non-emissive part of the first subpixel (R_SP) is not directly used for lower light emission but serves to block side leakage light transmitted to the red light-emitting part (REM).

[0049] BH, which is not described here, corresponds to the light-emitting parts (REM, GEM, BEM, WEM) of each subpixel as an open area between banks (119).

[0050] Hereinafter, a light-emitting display device according to a second embodiment of the present invention will be described.

[0051] FIG. 3 is a plan view of a light-emitting display device according to a second embodiment of the present invention, and FIG. 4 is a cross-sectional view of a light-emitting display device according to a second embodiment of the present invention.

[0052] As shown in FIGS. 3 and 4, the light-emitting display device according to the second embodiment of the present invention, compared with the first embodiment, further comprises a second auxiliary color conversion unit (OCF3, OCF4) in the non-light-emitting part around the white light-emitting part (WEM) of the fourth subpixel (W_SP).

[0053] The second auxiliary color conversion unit (OCF3, OCF4) also has a stacked configuration as shown in FIG. 4, comprising a first auxiliary color conversion layer (ARCF) that selectively transmits red and a second auxiliary color conversion layer (ABCF) that transmits colors other than red. The inclusion of the second auxiliary color conversion layer (ABCF) is intended to consider the function of blocking other colors rather than the transmission function of the second auxiliary color conversion layer (ABCF) itself, and the filter function of colors blocked by both the first and second auxiliary color conversion layers (ARCF, ABCF) is enhanced by the stacking of the first and second auxiliary color conversion layers (ARCF, ABCF). For example, the second auxiliary color conversion layer (ABCF) has a large difference in the transmission light region compared to the first auxiliary color conversion layer (ARCF), and it is preferable that it can transmit light of short wavelengths of 100 nm to 220 nm more than the transmission region of the first auxiliary color conversion layer (ARCF). In this case, the second auxiliary color conversion layer (ABCF) can be formed from the same material as the blue conversion layer (BCF) provided in the blue light emitting part (BEM). At this time, the first and second auxiliary color conversion parts (OCF1, OCF2 / OCF3, OCF4) are both double stacked of the first and second auxiliary color conversion layers (ARCF, ABCF), thereby double-blocking the green light that is relatively strongly emitted from the light emitting element (OLED) and preventing the color purity of the red light emitting part from being affected by lateral leakage of strong green light.

[0054] Since there is no 50% of the W60, the 50% of the 50% of the 50% of the 50% of the 50% of the 50% of the 50% of the 50% of the 50% of the 50% of the 50% of the 50% of the 50% of the 50% of the 50% of the 50% of the 50% of the W6% of the 50

[0055] Since the area of ​​the red light-emitting part (REM) and the white light-emitting part (WEM) may vary as needed, the first auxiliary color conversion part (OCF1, OCF2) provided on the upper and lower outer boundary lines of the red light-emitting part (REM) and the second auxiliary color conversion part (OCF3, OCF4) provided on the upper and lower outer boundary lines of the white light-emitting part (WEM) may have different widths.

[0056] Meanwhile, in the first and second embodiments, a green conversion layer (GCF) and a blue conversion layer (BCF) are extended and stacked respectively at the vertical boundary portions of the second subpixel (G_SP) and the third subpixel (B_SP), so that an auxiliary color conversion portion may be provided at the vertical outer portions of the light-emitting portions (GEM, BEM) of the second and third subpixels (G_SP, B_SP). In this case, the superimposed green conversion layer (GCF) and blue conversion layer (BCF) may have a blocking effect on leakage light in the non-light-emitting portion.

[0057] The description of the identical configurations of the first and second embodiments is omitted, and below, the specific configuration of the light-emitting element within the light-emitting display device of the present invention and the significance of the auxiliary color conversion unit having a configuration of the light-emitting element will be explained.

[0058] FIG. 5 is a cross-sectional view schematically showing a light-emitting element of the light-emitting display device of the present invention, and FIG. 6 is a cross-sectional view specifically showing a stack structure of a light-emitting element of the light-emitting display device of the present invention.

[0059] Figure 5 shows that the organic stack (OS) of the light-emitting device of Figure 2 is configured as three stacks (S1, S2, S3), and that each stack is equipped with a light-emitting layer.

[0060] As shown in FIG. 5, the first stack (S1) may have a first blue light-emitting layer (Blue1), the second stack (S2) may have a plurality of light-emitting layers (Red, YG, Green) with wavelengths longer than blue adjacent to each other, and the third stack (S3) may have a second blue light-emitting layer (Blue2).

[0061] The reason for providing blue in two stacks as a stack configuration in the organic stack is to increase the efficiency of blue, which has low visibility. The advantage of having a first and / or second auxiliary color conversion unit as a light-emitting display device of the present invention can also be obtained even when including the first stack (S1) and the second stack (S2) described above.

[0062] In addition, the light-emitting display device of the present invention may, in some cases, include additional stacks other than the first to third stacks (S1, S2, S3).

[0063] The second stack (S2) includes a red light-emitting layer (Red) and a green light-emitting layer (Green) in addition to a yellow-green light-emitting layer (YG) between the red light-emitting layer (Red) and the green light-emitting layer (Green) for displaying various colors by a multiple stack configuration.

[0064] Although the organic stack can be composed of only a red light-emitting layer (Red) and a yellow-green light-emitting layer (YG) in the second stack (S2) to produce a white spectrum, it is further provided with a green light-emitting layer (Green) that exhibits a similar white spectrum and improves brightness efficiency to match the level of brightness efficiency required in a light-emitting display device.

[0065] The light-emitting display device of the present invention has a structure in which a green light-emitting layer (Green) is added in addition to a red light-emitting layer and a yellow-green light-emitting layer, and the degradation of red purity of the first subpixel (red pixel) at low current density is resolved by the first and / or second auxiliary color conversion unit through the strong efficiency of the green light-emitting layer (Green).

[0066] Multiple stacks each have different color light-emitting layers or combinations of color light-emitting layers. Since at least one blue light-emitting layer among the color light-emitting layers has relatively lower efficiency compared to other color light-emitting layers, it is provided as a single light-emitting layer in one or more stacks. Color light-emitting layers other than the blue light-emitting layer may be configured by arranging multiple light-emitting layers in contact to improve the brightness of the entire light-emitting display device. A red light-emitting layer and a yellow-green light-emitting layer may be arranged in contact with each other in a stack different from the blue stack, or a red light-emitting layer, a yellow-green light-emitting layer, and a green light-emitting layer may be arranged in contact with each other.

[0067] As shown in FIG. 6, the first to third stacks (S1, S2, S3) between the first electrode (110) and the second electrode (200) are separated by the first and second charge generation layers (150, 170). In the first stack (S1), a hole-related portion (1210), a first blue light-emitting layer (130), and a first electron transport layer (124) may be stacked in sequence between the first electrode (110) and the first charge generation layer (150). The hole-related portion (1210) may include a hole injection layer (121) that assists in hole injection from the first electrode (110), a first hole transport layer (122) that transports holes from the hole injection layer (121) to the first blue light-emitting layer (130), and a second hole transport layer (123). The first and second hole transport layers (122, 123) may be formed as a two-layer structure as illustrated, or as a single layer. When formed as a two-layer structure, the first hole transport layer (122) has a hole transport function, and the second hole transport layer (123) has a function of preventing electrons and excitons from being transferred to the first hole transport layer (122) side along with hole transport to the first blue light-emitting layer (130).

[0068] The second stack (S2) is provided between the first and second charge generating layers (150, 170) and includes a heterogeneous light-emitting part (140) comprising a red light-emitting layer (141), a yellow-green light-emitting layer (142), and a green light-emitting layer (143) stacked adjacent to each other, and includes a third hole transport layer (125) below the red light-emitting layer (141) and a second electron transport layer (126) above the green light-emitting layer (143).

[0069] The third stack (S3) is provided between the second charge generation layer (170) and the second electrode (200), and the hole-related part (1250), the second blue light-emitting layer (160), and the third electron transport layer (129) may be stacked in sequence. The hole-related part (1250) includes a fourth hole transport layer (127) that transports holes from the second charge generation layer (170) to the second blue light-emitting layer (160), and a fifth hole transport layer (128) that prevents excitons and electrons of the second blue light-emitting layer (160) from being transferred downward along with the hole transport function.

[0070] The first and second charge generation layers (150, 170) between the stacks each include an n-type charge generation layer (151, 171) responsible for generating electrons and transferring electrons to adjacent stacks, and a p-type charge generation layer (153, 173) responsible for generating holes and transferring holes to adjacent stacks. In some cases, the first and second charge generation layers (150, 170) may be formed as a single layer by doping one or more hosts together with an n-type dopant and a p-type dopant.

[0071] In the following, as the first experiment, we examine the color characteristics by varying the configuration of the light-emitting element and the current density without applying an auxiliary color conversion unit.

[0072] Figures 7a and 7b are cross-sectional views showing Device A and Device B. Figure 8 is a graph showing the color gamut when Device A and Device B are driven at low current density. Figures 9a and 9b are graphs showing the intensity according to wavelength when Device A is driven at low and high current densities. Figures 10a and 10b are graphs showing the intensity according to wavelength when Device B is driven at low and high current densities. Figure 11 is a graph comparing the red intensity of Device A and Device B according to current density.

[0073] FIGS. 7a and 7b show Device A and Device B, which differ in the second stack having a different type of light-emitting part in the configuration of the light-emitting element in the first experiment. Device B is configured such that the same red light-emitting layer, yellow-green light-emitting layer, and green light-emitting layer as the light-emitting element described in FIG. 5 are stacked in the different type of light-emitting part, and Device A is configured such that only the red light-emitting layer and the yellow-green light-emitting layer are stacked compared to Device B.

[0074] As shown in Fig. 8, when examining the color gamut in the case where a color conversion layer is provided below the light-emitting part of the subpixel of the light-emitting elements of Device A and Device B, but an auxiliary color conversion unit is not applied, it can be seen that the blue and green color gamuts of both Device A and Device B are similar to the DCI level, but the red color gamut shows a significant difference from the DCI level. In particular, Device B has a larger difference from the DCI level in red color coordinates than Device A, which is interpreted as Device B using a relatively more efficient green light-emitting layer, causing the red color coordinates to approach white. The white light emitted from the light-emitting element is the sum of the light emitted from the light-emitting layers of each stack, and among the light-emitting layers provided in the organic stack, the one that has the most influence on brightness is the highly efficient green light-emitting layer (Green). This phenomenon of the red color gamut shifting implies that the purity of the red expression in the light-emitting display device is reduced, and since this is perceived by viewers as a degradation of image quality, it is a problem that needs to be improved.

[0075] In addition, FIGS. 9a and 9b show the white spectrum of Device A during low-density current driving and high-density current driving, exhibiting a similar shape regardless of density change. It can be seen that by providing a red light-emitting layer and a yellow-green light-emitting layer in the heterogeneous light-emitting part, yellow-green light-emitting characteristics are evenly exhibited during low-density current driving and high-density current driving.

[0076] On the other hand, Figures 10b and 10b show the white spectrum of Device B when driven at low and high current densities, respectively, and it can be seen that the red light emission intensity decreases and the green light emission intensity increases when driven at low current densities compared to when driven at high current densities.

[0077] When comparing the red efficiency of Device A and Device B through Fig. 11, it can be seen that Device B has lower efficiency than Device A when driven at a low current density of 1 mA / cm2 or less. This means that in Device B, which has a green light-emitting layer additionally provided in the irregular light-emitting part for higher efficiency compared to the structure of Device A, the red light-emitting efficiency drops sharply when driven at low current density.

[0078] The light-emitting display device of the present invention is intended to solve the problem of red color purity during low-density current driving by providing an auxiliary color conversion unit of the non-light-emitting part in a situation where a green light-emitting layer is provided in the irregular light-emitting part to improve the brightness of the display device.

[0079] In particular, the light-emitting display device of the present invention is equipped with a first auxiliary color conversion unit in a non-light-emitting part surrounding a red light-emitting part to improve the problematic red purity, thereby preventing the influence of leakage light around the red light-emitting part. In addition, a second auxiliary color conversion unit is equipped in a non-light-emitting part surrounding a white light-emitting part to further improve the effect of preventing the influence of leakage light around the red light-emitting part.

[0080] In the second experiment, the significance of the light-emitting display device of the present invention is examined by changing the configuration of the color conversion layer of the non-light-emitting part in a structure having red, yellow-green, and green light-emitting layers in the heterogeneous light-emitting part of FIGS. 5, 6, and 7b.

[0081] FIGS. 12a to 12f are cross-sectional views according to the first to sixth experimental examples, and FIG. 13 is a graph showing CIEx and CIEy of the first experimental example. FIGS. 14a to 14c are graphs showing CIEx according to the second to fourth experimental examples, FIG. 15a is a graph comparing CIEx according to the second, fifth, and sixth experimental examples, and FIG. 15b is a graph comparing CIEx according to the first and sixth experimental examples.

[0082] In the first experimental example (Ex1) to the sixth experimental example (Ex6) of FIGS. 12a to 12f, the light-emitting display device is shown as a red subpixel to examine the effect of leakage light, and components that do not affect light emission on the substrate (100) are omitted. Each red subpixel is provided with a red conversion layer (RCF) in the light-emitting part, and includes a light-emitting element (OLED) of the configuration of FIG. 6 on a flattening layer (250) that flatly covers the red conversion layer (RCF). That is, the light-emitting element (OLED) includes first to third stacks (S1, S2, S3) between the first electrode (110) and the second electrode (200), the first and third stacks (S1, S3) have a single blue light-emitting layer (130, 160), and the second stack (S2) has a heterogeneous light-emitting part (140) in which a red light-emitting layer (141), a yellow-green light-emitting layer (142), and a green light-emitting layer (143) are stacked.

[0083] FIGS. 12a to 12f show that a thin-film transistor (TFT) is included in the non-emissive portion of a red subpixel, and whether an auxiliary color conversion layer is applied to the non-overlapping area with the thin-film transistor (TFT) varies. That is, as shown in FIG. 12a, the first experimental example (Ex1) does not apply an auxiliary color conversion layer to the non-emissive portion, and as shown in FIG. 12b, the second experimental example (Ex2) applies an auxiliary color conversion layer (ARCF) identical to the red conversion layer (RCF) to the non-emissive portion. As shown in FIG. 12c, the third experimental example (Ex3) applies an auxiliary color conversion layer (AGCF) identical to the green conversion layer (GCF) to the non-emissive portion. As shown in FIG. 12d, the fourth experimental example (Ex4) applies an auxiliary color conversion layer (BCF) identical to the blue conversion layer (BCF) to the non-emissive portion. As shown in FIG. 12e, the fifth experimental example (Ex5) has a first auxiliary color conversion layer (AGCF) identical to the green conversion layer (GCF) and a second auxiliary color conversion layer (ARCF) identical to the red conversion layer (RCF) laminated in the non-emissive part. Since the common filter characteristics of the first and second auxiliary color conversion layers (AGCF, ARCF) are important, the first and second auxiliary color conversion layers (AGCF, ARCF) have the same effect regardless of their vertical order. As shown in FIG. 12f, the sixth experimental example (Ex6) has a first auxiliary color conversion layer (ABCF) identical to the blue conversion layer (BCF) and a second auxiliary color conversion layer (ARCF) identical to the red conversion layer (RCF) laminated in the non-emissive part. In the 6th experimental example (Ex6), the first and second auxiliary color conversion layers (ABCF, ARCF) have common filter characteristics that are important, and the first and second auxiliary color conversion layers (AGCF, ARCF) have the same effect regardless of their vertical order.

[0084] Figure 13 shows the color efficiency of the first experimental example (Ex1), which corresponds to the case where the red subpixel does not have an auxiliary color conversion unit in the non-emissive part. It can be seen that when the CIEx value changes from 0.0001 mA / cm2 to 1 mA / cm2, it shows a significant change to approximately 0.300. Relatively speaking, the CIEy value shows a change amount of less than 0.0800 due to the change in current density, which is less variability than the CIEx value, indicating that the sensitivity of the CIEx value is high in red display. Since similar color coordinate values ​​are expected when the CIEx value is matched to a level similar to that of low-density driving and high-density current driving, the changes in the CIEx value are mainly examined below in the second to sixth experimental examples (Ex2~Ex6).

[0085] As shown in FIG. 14a, when a red auxiliary color conversion layer (ARCF) is provided as the auxiliary color conversion unit in the second experimental example (Ex2), it can be seen that the color purity of red is significantly improved because it blocks light emission of other colors other than red. In addition, in the case of the third and fourth experimental examples (Ex3, Ex4) in FIG. 14b and FIG. 14c, compared to the first experimental example (Ex1) in FIG. 13, the CIEx value increases at a current density of 0.0001 mA / cm2, indicating some degree of improvement. However, compared to the second experimental example (Ex2), the effect is relatively small when an auxiliary green conversion layer (AGCF) and an auxiliary blue conversion layer (ABCF) are provided as the auxiliary color conversion layers in the third and fourth experimental examples (Ex3, Ex4). This is because the contribution to the X tristimulus component, which is the only component in the blue region of the lateral leakage light emission components that significantly affects red among the tristimulus values, is the smallest. In addition, in the case of the third and fourth experimental examples (Ex3, Ex4), green and blue leakage light-emitting components are generated in the non-luminous parts of the subpixels by the organic stack (OS) provided in the subpixels, and it is understood that the red color purity is reduced by being transmitted through the auxiliary green conversion layer (AGCF) and auxiliary blue conversion layer (ABCF) that transmit light in the green and blue regions among the leakage light-emitting components.

[0086] Meanwhile, the 5th and 6th experimental examples (Ex5, Ex6) use the red conversion layer confirmed in the 2nd experimental example (Ex2) as the first auxiliary color conversion layer (ARCF) to have an exclusion effect other than red, and additionally provide a color conversion layer with transmission characteristics different from red as the second auxiliary color conversion layer (AGCF / ABCF) to enhance the filtering effect.

[0087] As shown in Fig. 15a, compared to the second experimental example (Ex2) of a single red conversion layer structure, it can be seen that the change in CIEx values ​​at low and high current densities is small in the fifth and sixth experimental examples (Ex5, Ex6) of a double stacked structure.

[0088] The light-emitting display device of the present invention is based on Experimental Example 6 (Ex6), in which the difference in color coordinates is smallest when driving at low current density and high current density, and it can be confirmed that the change in CIEx appears to be less than three decimal places. This is because, in the light-emitting element of Fig. 6, the contribution of the green light-emitting layer increases due to the peak characteristics of yellow-green light emission, which mainly emits at low current density due to structural characteristics. At this time, by stacking a first auxiliary color-converting layer (ARCF) that transmits red and blocks green and blue to the non-light-emitting part and a second auxiliary color-converting layer (ABCF) that transmits blue and blocks red and green, the amount of green light emission caused by this increased lateral leakage is removed by a double filter effect, thereby preventing or eliminating lateral leakage in the non-light-emitting part. In particular, when the transmission spectrum of the first auxiliary color conversion layer (ARCF) and the second auxiliary color conversion layer (ABCF), which have a significantly reduced transmission range, is superimposed, the amount of light transmitted through both the first and second auxiliary color conversion layers (ARCF, ABCF) virtually disappears, resulting in a black state, thereby preventing leakage of light from the non-emissive part and significantly improving the color purity of the red subpixel.

[0089] Experimental Example Auxiliary color conversion unit [Δu'v' at 10mA / cm 2 ]- [Δu'v' at 0.1mA / cm 2 ] Ex1 doesn't exist 0.282 Ex2 ARCF 0.003 Ex3 AGCF 0.197 Ex4 ABCF 0.250 Ex5 ARCF+AGCF 0.001 Ex6 ARCF+ABCF 0.000

[0090] Table 1 shows 10 mA / cm² in Experimental Examples 1 to 6. 2 Current density and 0.1 mA / cm² 2 As shown in Figure 15b and Table 1, the color deviation observed through the difference in CIEx values ​​at current density indicates that while the color deviation in the first experimental example (Ex1) was 0.282, it was 0.000 in the sixth experimental example (Ex6), confirming that the improvement is significant when the auxiliary color conversion unit of the present invention is applied. If only a red conversion layer is used as the auxiliary color conversion layer, some light may help improve red luminance; however, since the actual light-emitting display device includes a yellow-green light-emitting layer, the intensity of red is very low at extremely low currents. Due to the nature of white driving caused by lateral leakage, the current density is inevitably very low, and the white spectrum emitted in this region has almost no red region; therefore, even if the leakage light caused by the leaked white light passes through the red conversion layer, the improvement in red color purity may be low.

[0091] Therefore, the light-emitting display device of the present invention can prevent degradation of color purity due to lateral leakage by using a red conversion layer and simultaneously stacking a blue conversion layer with a significantly different wavelength range.

[0092] Below, we examine the CIEx color coordinate characteristics of the Device A and Device B structures, specifically the structure in which a single red conversion layer is applied to the lower non-emissive part, the structure in which a red conversion layer and a green conversion layer are stacked, and the structure in which a red conversion layer and a blue conversion layer are applied.

[0093] FIG. 16 is a graph comparing CIEx when a single red conversion layer (Ex2a), a stacked structure of a red conversion layer and a green conversion layer (Ex5a), and a stacked structure of a red conversion layer and a blue conversion layer (Ex6a) are applied to the non-emissive part of Device A, and FIG. 17 is a graph comparing CIEx when a single red conversion layer (Ex2), a stacked structure of a red conversion layer and a green conversion layer (Ex5), and a stacked structure of a red conversion layer and a blue conversion layer (Ex6) are applied to the non-emissive part of Device B.

[0094] As shown in FIG. 16, the Device A structure does not have a green light-emitting layer, so 0.0001 mA / cm 2 It can be seen that the variation in CIEx value at low current density is small compared to the Device B structure, and that the auxiliary color conversion unit is provided with a single auxiliary red conversion layer (ARCF) in the relatively non-emissive part, and is less than 0.0005 in the structure where the auxiliary red conversion layer (ARCF) and the auxiliary blue conversion layer (ABCF) or auxiliary green conversion layer (AGCF) are stacked, indicating that the effect of providing an auxiliary color conversion unit with a multiple stacked structure is negligible.

[0095] Relatively speaking, as shown in FIG. 17, by providing a green light-emitting layer, it can be confirmed that the CIEx color coordinate variability at low current density is smaller in the 5th and 6th experimental examples (Ex5, Ex6), which are equipped with an auxiliary red conversion layer (ARCF) and a color conversion layer with different wavelength transmittance, compared to the 2nd experimental example (Ex2), which is equipped with a single auxiliary color conversion unit consisting of a red conversion layer, and in particular, in the case of the 6th experimental example (Ex6), 0.0001 mA / cm² is lower than that of the 2nd experimental example (Ex2). 2 It can be seen that the variation in CIEx values ​​at low current density is improved by more than 0.0020.

[0096] The light-emitting display device of the present invention can improve the color purity of red by blocking colors other than red that cause leakage, in a structure in which a high-efficiency green light-emitting layer is provided in addition to a red light-emitting layer for a different type of light-emitting element to improve luminance efficiency, and an auxiliary color conversion unit having a structure in which a red conversion layer and a blue conversion layer are laminated on the outer side of the red light-emitting element at the bottom of the light-emitting element. In particular, through the dual-structured auxiliary color conversion unit, color deviation can be prevented at low and high current densities, enabling uniform color expression regardless of current density and thereby improving image quality.

[0097] In addition, the light-emitting display device of the present invention can further enhance the effect of preventing the degradation of red color purity caused by lateral leakage and improving the image quality of the display device by further providing a double-structured auxiliary color conversion unit on the outer side of the white light-emitting unit.

[0098] The light-emitting display device of the present invention further comprises a blue conversion layer around a red light-emitting part by overlapping with a red conversion layer provided in a red subpixel, thereby blocking light emitted from areas other than the light-emitting part with the color conversion layer to prevent a decrease in color purity when driving the red subpixel.

[0099] A light-emitting display device according to an embodiment of the present invention comprises: a substrate including a first subpixel, a second subpixel, a third subpixel, and a fourth subpixel, each having a light-emitting portion and a non-light-emitting portion surrounding the light-emitting portion; a red conversion layer, a green conversion layer, and a blue conversion layer provided on the substrate, respectively, corresponding to the light-emitting portions of the first subpixel, the second subpixel, and the third subpixel; a first auxiliary color conversion unit having a first auxiliary color conversion layer that transmits red light and a second auxiliary color conversion layer that transmits light with a shorter wavelength than the red light, stacked on the non-light-emitting portion of the first subpixel; a flattening layer covering the red conversion layer, the green conversion layer, the blue conversion layer, and the first auxiliary color conversion unit; and a first stack provided on the flattening layer across the first to fourth subpixels, comprising a first electrode, a second electrode facing each other, and a first blue light-emitting layer between the first and second electrodes. It may include a light-emitting element having a second stack including a red light-emitting layer and a green light-emitting layer, and a first charge-generating layer between the first and second stacks.

[0100] The second auxiliary color conversion layer can transmit light with a short wavelength of 100 nm to 220 nm more than the first auxiliary color conversion layer.

[0101] The non-emissive portion of the fourth subpixel may further include a second auxiliary color conversion portion in which a third auxiliary color conversion layer of the same layer as the red conversion layer and a fourth auxiliary color conversion layer of the same layer as the blue conversion layer are stacked.

[0102] The non-emissive portion of the second subpixel may further include a third auxiliary color conversion unit having a fifth auxiliary color conversion layer of the same layer as the blue conversion layer.

[0103] The first electrode is provided spaced apart from each of the first to fourth subpixels, and the first stack and second stack, the first charge generating layer and the second electrode may be provided continuously in the first to fourth subpixels.

[0104] A bank is further provided in the non-emissive portion of the first to fourth subpixels, and at least one of the first auxiliary color conversion unit and the second auxiliary color conversion unit can overlap with the bank.

[0105] The first auxiliary color conversion unit may be provided in the non-emitting part along the upper and lower outlines of the emitting part of the first subpixel, and the second auxiliary color conversion unit may be provided in the non-emitting part along the upper and lower outlines of the emitting part of the second subpixel.

[0106] The above bank can overlap with the red light-emitting layer, the green light-emitting layer, and the first blue light-emitting layer.

[0107] A third stack may be further included between the second stack and the second electrode, and the third stack may include a second blue light-emitting layer.

[0108] The second stack further includes a yellow-green light-emitting layer between the red light-emitting layer and the green light-emitting layer, and both surfaces of the yellow-green light-emitting layer can be in contact with the red light-emitting layer and the green light-emitting layer.

[0109] Each of the first to fourth subpixels may further include a thin-film transistor, and the first auxiliary color conversion unit may not overlap with the thin-film transistor.

[0110] Meanwhile, it will be obvious to those skilled in the art that the present invention described above is not limited to the embodiments and attached drawings described above, and that various substitutions, modifications, and changes are possible within the scope of the technical concept of the present invention. Explanation of the symbols

[0111] 100: Substrate 110: First electrode 119: Bank TFT: (Thin-film) Transistor OS: Organic Stack OLED: Light Emitting Device 130: First blue light-emitting layer 140: Irregular light-emitting part 141: Red light-emitting layer 142: Yellow-green light-emitting layer 143: Green light-emitting layer 160: Second blue light-emitting layer 150, 170: Charge generation layer 200: Second electrode

Claims

Claim 1 A substrate comprising a first subpixel, a second subpixel, a third subpixel, and a fourth subpixel, each having a light-emitting portion and a non-light-emitting portion surrounding the light-emitting portion; a red conversion layer, a green conversion layer, and a blue conversion layer each provided on the substrate corresponding to the light-emitting portions of the first subpixel, the second subpixel, and the third subpixel; a first auxiliary color conversion portion having a first auxiliary color conversion layer that transmits red light and a second auxiliary color conversion layer that transmits light with a shorter wavelength than the red light stacked on the non-light-emitting portion of the first subpixel; and a flattening layer covering the red conversion layer, the green conversion layer, the blue conversion layer, and the first auxiliary color conversion portion. A light-emitting display device comprising a light-emitting element having a first electrode, a second electrode, and a first stack including a first blue light-emitting layer between the first and second electrodes, a second stack including a red light-emitting layer and a green light-emitting layer, and a first charge-generating layer between the first and second stacks, wherein the first auxiliary color conversion unit overlaps at least a portion with the first electrode of the first subpixel. Claim 2 In claim 1, the second auxiliary color conversion layer transmits light of a short wavelength of 100 nm to 220 nm more than the first auxiliary color conversion layer, in a light-emitting display device. Claim 3 A light-emitting display device according to claim 1, further comprising a second auxiliary color conversion unit in which a third auxiliary color conversion layer of the same layer as the red conversion layer and a fourth auxiliary color conversion layer of the same layer as the blue conversion layer are laminated on the non-light-emitting part of the fourth subpixel. Claim 4 In claim 3, a light-emitting display device further comprising a third auxiliary color conversion unit having a fifth auxiliary color conversion layer of the same layer as the blue conversion layer in the non-light-emitting part of the second subpixel. Claim 5 A light-emitting display device according to any one of claims 1 to 4, wherein the first electrode is spaced apart from each of the first to fourth subpixels, and the first stack and second stack, the first charge generating layer and the second electrode are continuously provided in the first to fourth subpixels. Claim 6 In claim 3, a light-emitting display device further comprising a bank in the non-light-emitting portion of the first to fourth subpixels, wherein at least one of the first auxiliary color conversion unit and the second auxiliary color conversion unit is superimposed with the bank. Claim 7 In claim 3, the first auxiliary color conversion unit is provided in the non-emitting part along the upper and lower outlines of the emitting part of the first subpixel, and the second auxiliary color conversion unit is provided in the non-emitting part along the upper and lower outlines of the emitting part of the fourth subpixel. Claim 8 In claim 6, the bank is a light-emitting display device superimposed with the red light-emitting layer, the green light-emitting layer, and the first blue light-emitting layer. Claim 9 A light-emitting display device according to claim 1, further comprising a third stack between the second stack and the second electrode, wherein the third stack includes a second blue light-emitting layer. Claim 10 In claim 1, the second stack further comprises a yellow-green light-emitting layer between the red light-emitting layer and the green light-emitting layer, and the yellow-green light-emitting layer is a light-emitting display device having both surfaces in contact with the red light-emitting layer and the green light-emitting layer, respectively. Claim 11 In claim 1, each non-luminous portion of the first to fourth subpixels further includes a thin-film transistor, and the first auxiliary color conversion portion is a light-emitting display device that is non-overlapping with the thin-film transistor. Claim 12 In claim 1, the first auxiliary color conversion layer is integral with the first color conversion layer and is arranged extending from the emitting portion to the non-emitting portion of the first subpixel, and the second auxiliary color conversion layer is disposed on the first auxiliary color conversion layer and is spaced apart from each of the second and third color conversion layers. Claim 13 In claim 1, the light-emitting display device in which the first auxiliary color conversion layer is not placed in the second and third subpixels. Claim 14 In claim 1, in each of the first to fourth subpixels, the first electrode includes a light-emitting part overlapping part and a non-light-emitting part overlapping part, the non-light-emitting part overlapping part includes a connecting part with a narrower width than the light-emitting part overlapping part in an area adjacent to the light-emitting part overlapping part, and the first auxiliary color conversion part is arranged in the first subpixel to overlap the connecting part but have a wider width than the connecting part. Claim 15 In claim 3, in each of the first to fourth subpixels, the first electrode includes a light-emitting part overlapping part and a non-light-emitting part overlapping part, and the non-light-emitting part overlapping part includes a connecting part that is narrower than the light-emitting part overlapping part in an area adjacent to the light-emitting part overlapping part, and the second auxiliary color conversion part is longer than the first auxiliary color conversion part in the longitudinal direction of the connecting part, in a light-emitting display device.

Images