Display device
Patent Information
- Application Number
- KR1020200185323
- Authority / Receiving Office
- KR · KR
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2020-12-28
- Publication Date
- 2026-09-04
- Estimated Expiration
- 2040-12-28
Smart Images

Figure 112020142285648-PAT00002_ABST
Abstract
Description
Technology Field
[0001] The present invention relates to a display device. Background Technology
[0002] The importance of display devices is increasing along with the development of multimedia. In response to this, various types of display devices, such as Organic Light Emitting Displays (OLEDs) and Liquid Crystal Displays (LCDs), are being used.
[0003] A device for displaying images of a display device includes a display panel such as an organic light-emitting display panel or a liquid crystal display panel. Among these, as a light-emitting display panel, it may include a light-emitting element; for example, in the case of a light-emitting diode (LED), there are organic light-emitting diodes (OLEDs) that use organic materials as light-emitting materials and inorganic light-emitting diodes that use inorganic materials as light-emitting materials. The problem to be solved
[0004] The problem that the present invention aims to solve is to provide a display device capable of improving display quality by reducing the reflection of external light.
[0005] The problems of the present invention are not limited to those mentioned above, and other unmentioned technical problems will be clearly understood by those skilled in the art from the description below. means of solving the problem
[0006] A display device according to an embodiment for solving the above problem comprises a substrate including a first light-emitting region, a second light-emitting region, and a third light-emitting region, and a light-blocking region that partitions them; a plurality of light-emitting elements disposed on the substrate and respectively disposed in the first light-emitting region, the second light-emitting region, and the third light-emitting region; a flattening layer disposed on the plurality of light-emitting elements; a wavelength conversion layer disposed on the flattening layer and including wavelength conversion units, a light-transmitting unit, and a color conversion member; and a color filter layer disposed on the wavelength conversion layer and including a color filter, wherein the wavelength conversion units are respectively disposed in the first light-emitting region and the second light-emitting region, the light-transmitting unit is disposed in the third light-emitting region, and the color conversion member may be disposed between the flattening layer and the wavelength conversion unit and between the flattening layer and the light-transmitting unit.
[0007] The color conversion member may be positioned closer to the light-emitting element than the wavelength conversion members and the light transmission member.
[0008] The above color conversion member can transmit a color identical to the color of light emitted from the plurality of light-emitting elements.
[0009] The above color conversion member may be a color filter that transmits blue light.
[0010] The refractive index of the color conversion member may be greater than the refractive index of the flattening layer.
[0011] The wavelength conversion layer comprises a first light-blocking member disposed on the flattening layer, wherein the first light-blocking member overlaps with the light-blocking region and may not overlap with the first light-emitting region, the second light-emitting region, and the third light-emitting region.
[0012] The color conversion member, the wavelength conversion member, and the light transmission member may be disposed between the first light-blocking member.
[0013] The color filter layer comprises a reflective layer and a second light-blocking member disposed on the wavelength conversion layer, and the reflective layer and the second light-blocking member may overlap with the first light-emitting region, the second light-emitting region, the third light-emitting region, and the light-blocking region.
[0014] The reflective layer includes a plurality of first holes that overlap with the first light-emitting region, the second light-emitting region, and the third light-emitting region, and the second light-blocking member includes a plurality of second holes that overlap with the first light-emitting region, the second light-emitting region, and the third light-emitting region, and the plurality of first holes and the plurality of second holes can overlap each other.
[0015] The planar shape of the plurality of first holes and the plurality of second holes may be a stripe shape or a dot shape.
[0016] The above color filter is placed in the first light-emitting region and the second light-emitting region, respectively, and can be non-overlapping with the third light-emitting region.
[0017] The above color filter may be a color filter that blocks blue light.
[0018] It may further include a first electrode and a second electrode disposed on the substrate and extending in one direction, the light-emitting element aligned on the first electrode and the second electrode, a first connecting electrode connected to one end of the light-emitting element, and a second connecting electrode connected to the other end of the light-emitting element.
[0019] The light-emitting element comprises a first semiconductor layer, a second semiconductor layer disposed on the first semiconductor layer, and a light-emitting layer disposed between the first semiconductor layer and the second semiconductor layer, and may include an insulating film surrounding the first semiconductor layer, the second semiconductor layer, and the light-emitting layer.
[0020] Additionally, a display device according to one embodiment comprises a substrate including a first light-emitting region, a second light-emitting region, and a third light-emitting region, and a light-blocking region that partitions them; a plurality of light-emitting elements disposed on the substrate and respectively disposed in the first light-emitting region, the second light-emitting region, and the third light-emitting region; an encapsulation layer disposed on the plurality of light-emitting elements; a wavelength conversion layer disposed on the encapsulation layer and including wavelength conversion units, a light-transmitting unit, and a color conversion member; and a color filter layer disposed on the wavelength conversion layer and including a color filter, wherein the color conversion member is disposed on the encapsulation layer, the wavelength conversion units are respectively disposed on the color conversion member in the first light-emitting region and the second light-emitting region, the light-transmitting unit is disposed on the color conversion member in the third light-emitting region, and the color conversion member may overlap with the first light-emitting region, the second light-emitting region, the third light-emitting region, and the light-blocking region.
[0021] The wavelength conversion layer includes a first light-blocking member that overlaps with the light-blocking region, and the color conversion member may be in contact with the upper surface of the encapsulation layer and may be in contact with the lower surface of the first light-blocking member, the wavelength conversion parts, and the light-transmitting part.
[0022] It further includes a flattening layer disposed between the above-mentioned encapsulation layer and the above-mentioned color conversion member, wherein the lower surface of the above-mentioned color conversion member may be in contact with the upper surface of the above-mentioned flattening layer.
[0023] The thickness of the color conversion member may be the same in the first light-emitting region, the second light-emitting region, and the third light-emitting region.
[0024] The refractive index of the color conversion member may be greater than the refractive index of the flattening layer.
[0025] The above color conversion member can transmit light of the same color as the light emitted from the plurality of light-emitting elements.
[0026] Specific details of other embodiments are included in the detailed description and drawings. Effects of the invention
[0027] According to the display device of the embodiments, by including a color conversion member, the reflection of external light incident from the outside can be reduced, thereby improving the display quality. In addition, the light emission efficiency of the light provided by the light-emitting element can be improved, thereby improving the display quality.
[0028] The effects according to the embodiments are not limited to those exemplified above, and a wider variety of effects are included in this specification. Brief explanation of the drawing
[0029] FIG. 1 is a schematic plan view of a display device according to one embodiment. FIG. 2 is a cross-sectional view schematically showing some subpixels of a display device according to one embodiment. FIG. 3 is a plan view showing one pixel of a display device according to one embodiment. Figure 4 is a cross-sectional view taken along the Q1-Q1' line, Q2-Q2' line and Q3-Q3' line of Figure 3. FIG. 5 is a schematic diagram of a light-emitting element according to one embodiment. FIG. 6 is a plan view showing the arrangement of a color conversion member of a display device according to one embodiment. Figure 7 is an enlarged view of area A of Figure 2. FIGS. 8 to 10 are plan views showing various shapes of a reflective layer and a second light-blocking member according to one embodiment. FIG. 11 is a cross-sectional view showing a display device according to another embodiment. FIG. 12 is a plan view showing a color conversion member of a display device according to another embodiment. FIG. 13 is a cross-sectional view showing a display device according to another embodiment. Specific details for implementing the invention
[0030] The advantages and features of the present invention and the methods for achieving them will become clear by referring to the embodiments described below in detail together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below but may be implemented in various different forms. These embodiments are provided merely to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention, and the present invention is defined only by the scope of the claims.
[0031] When elements or layers are referred to as being "on" another element or layer, this includes cases where another layer or element is interposed directly on or in the middle of another element. Throughout the specification, the same reference numerals refer to the same components. Shapes, sizes, ratios, angles, numbers, etc., disclosed in the drawings for describing embodiments are exemplary and therefore the invention is not limited to the depicted details.
[0032] Although terms such as "first," "second," etc., are used to describe various components, it goes without saying that these components are not limited by these terms. These terms are used merely to distinguish one component from another. Therefore, it goes without saying that the first component mentioned below may also be the second component within the technical scope of the present invention.
[0033] The features of each of the 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 embodiment may be implemented independently of one another or may be implemented together in an associated relationship.
[0034] Specific embodiments will be described below with reference to the attached drawings.
[0035] FIG. 1 is a schematic plan view of a display device according to one embodiment.
[0036] Referring to FIG. 1, the display device (10) displays a video or a still image. The display device (10) may refer to any electronic device that provides a display screen. For example, a television, laptop, monitor, billboard, Internet of Things, mobile phone, smartphone, tablet PC (Personal Computer), electronic watch, smart watch, watch phone, head-mounted display, mobile communication terminal, electronic notebook, electronic book, PMP (Portable Multimedia Player), navigation, game console, digital camera, camcorder, etc. that provide a display screen may be included in the display device (10).
[0037] The display device (10) includes a display panel that provides a display screen. Examples of display panels include an inorganic light-emitting diode display panel, an organic light-emitting diode display panel, a quantum dot light-emitting diode display panel, a plasma display panel, a field emission display panel, etc. In the following examples, an inorganic light-emitting diode display panel is used as an example of a display panel, but it is not limited thereto, and if the same technical concept is applicable, it can be applied to other display panels.
[0038] In the drawing describing the display device (10), a first direction (DR1), a second direction (DR2), and a third direction (DR3) are defined. The first direction (DR1) and the second direction (DR2) may be directions perpendicular to each other within a single plane. The third direction (DR3) may be a direction perpendicular to the plane where the first direction (DR1) and the second direction (DR2) are located. The third direction (DR3) is perpendicular to each of the first direction (DR1) and the second direction (DR2). In the embodiment describing the display device (10), the third direction (DR3) represents the thickness direction of the display device (10).
[0039] The shape of the display device (10) can be varied in many ways. For example, the display device (10) may have a rectangular shape in which the first direction (DR1) in the plane includes a longer side than the second direction (DR2). As another example, the display device (10) may have a rectangular shape in which the second direction (DR2) in the plane includes a longer side than the first direction (DR1). However, it is not limited thereto and may have a shape such as a square, a square with rounded corners (vertices), other polygons, a circle, etc. The shape of the display area (DPA) of the display device (10) may also be similar to the overall shape of the display device (10). In FIG. 1, a display device (10) and a display area (DPA) having a rectangular shape in which the first direction (DR1) is longer than the second direction (DR2) are illustrated.
[0040] The display device (10) may include a display area (DPA) and a non-display area (NDA). The display area (DPA) is an area where the screen can be displayed, and the non-display area (NDA) is an area where the screen is not displayed. The display area (DPA) may also be referred to as an active area, and the non-display area (NDA) as an inactive area. The display area (DPA) may generally occupy the center of the display device (10).
[0041] The display area (DPA) may include a plurality of pixels (PX). The plurality of pixels (PX) may be arranged in a matrix direction. The shape of each pixel (PX) may be a planar rectangle or a square, but is not limited thereto, and may be a rhombus shape with each side tilted toward one direction. Each pixel (PX) may be arranged alternately in a stripe type or a pentile type. Additionally, each of the pixels (PX) may include one or more light-emitting elements that emit light of a specific wavelength range to display a specific color.
[0042] A non-display area (NDA) may be placed around a display area (DPA). The non-display area (NDA) may surround the display area (DPA) in whole or in part. The display area (DPA) is rectangular in shape, and the non-display area (NDA) may be placed adjacent to the four sides of the display area (DPA). The non-display area (NDA) may form the bezel of the display device (10). In each non-display area (NDA), wiring or circuit drivers included in the display device (10) may be placed, or external devices may be mounted.
[0043] FIG. 2 is a cross-sectional view schematically showing some subpixels of a display device according to one embodiment.
[0044] Referring to FIG. 2, the display area ('DPA' in FIG. 1) of the display device (10) may include first to third light-emitting areas (LA1, LA2, LA3). Each of the first to third light-emitting areas (LA1, LA2, LA3) may be an area where light generated from a light-emitting element (30) of the display device (10) is emitted to the outside of the display device (10). Additionally, the display area of the display device (10) may include first to third light-blocking areas (BA1, BA2, BA3) that partition and surround the first to third light-emitting areas (LA1, LA2, LA3).
[0045] The display device (10) may include a substrate (11), a buffer layer (12), a transistor layer (TFTL), a light-emitting element layer (EML), a wavelength conversion layer (WLCL), and a color filter layer (CFL).
[0046] The substrate (11) may be a base substrate or a base member and may be made of an insulating material such as a polymer resin. For example, the substrate (11) may be a flexible substrate capable of bending, folding, rolling, etc. The substrate (11) may include polyimide (PI), but is not limited thereto.
[0047] The buffer layer (12) may be disposed on the substrate (11). The buffer layer (12) may be made of an inorganic film capable of preventing the penetration of air or moisture. For example, the buffer layer (12) may include a plurality of inorganic films stacked alternately.
[0048] A transistor layer (TFTL) may be disposed on the buffer layer (12). The transistor layer (TFTL) may include a first transistor (T1), a first gate insulating layer (13), a first interlayer insulating layer (15), a second interlayer insulating layer (17), and a first flattening layer (19).
[0049] The first transistor (T1) may be placed on the buffer layer (12) and may constitute a pixel circuit for each of a plurality of pixels. For example, the first transistor (T1) may be a driving transistor or a switching transistor of a pixel circuit. The first transistor (T1) may include an active layer (ACT), a gate electrode (G1), a source electrode (SE), and a drain electrode (DE). The active layer (ACT) may include a plurality of conductive regions (ACTa, ACTb) and a channel region (ACTc) between them.
[0050] A light-emitting element layer (EML) may be disposed on a transistor layer (TFTL). The light-emitting element layer (EML) may include a first pattern (BNL1), a light-emitting element (30), and a second pattern (BNL2). The light-emitting element (30) may be disposed on the first transistor (T1). The light-emitting element (30) may be disposed between the first electrode and the second electrode and connected to the first connecting electrode and the second connecting electrode, respectively.
[0051] A detailed description of the aforementioned transistor layer (TFTL) and light-emitting element layer (EML) will be provided later with reference to FIGS. 3 to 5.
[0052] An encapsulation layer (TFE) may be disposed on a light-emitting element layer (EML). The encapsulation layer (TFE) may cover the upper surface and the side surface of the light-emitting element layer (EML). For example, the encapsulation layer (TFE) may include at least one inorganic film to prevent the penetration of oxygen or moisture. Additionally, the encapsulation layer (TFE) may include at least one organic film to protect the light-emitting element layer (EML) from foreign substances such as dust. For example, the encapsulation layer (TFE) may be composed of a structure in which at least one organic film is laminated between two inorganic films. The inorganic films may each include silicon nitride, aluminum nitride, zirconium nitride, titanium nitride, hafnium nitride, tantalum nitride, silicon oxide, aluminum oxide, titanium oxide, tin oxide, cerium oxide, silicon oxynitride, lithium fluoride, etc. The organic film may include acrylic resin, methacrylate resin, polyisoprene, vinyl resin, epoxy resin, urethane resin, cellulose resin, and perylene resin. However, the structure of the encapsulation layer (TFE) is not limited to the examples described above, and the laminated structure may be varied.
[0053] A second flattening layer (41) may be disposed on the encapsulation layer (TFE) to flatten the upper surface of the encapsulation layer (TFE). The second flattening layer (41) may include an organic material. For example, the second flattening layer (41) may include at least one of acrylic resin, epoxy resin, phenolic resin, polyamide resin, and polyimide resin.
[0054] A wavelength conversion layer (WLCL) may be disposed on the second flattening layer (41). The wavelength conversion layer (WLCL) may include a first light-blocking member (BK1), a first wavelength conversion unit (WLC1), a second wavelength conversion unit (WLC2), a light-transmitting unit (LTU), and a first capping layer (CAP1). Additionally, the wavelength conversion layer (WLCL) may further include a color conversion member (CCL). A detailed description of the color conversion member (CCL) will be provided later.
[0055] The first light-blocking member (BK1) may be placed in an overlapping manner with the first to third light-blocking regions (BA1, BA2, BA3) on the second flattening layer (41). The first light-blocking member (BK1) may be placed in an overlapping manner with the second pattern (BNL2) in the thickness direction. The first light-blocking member (BK1) can block the transmission of light. The first light-blocking member (BK1) can improve the color reproduction rate by preventing light from intruding and mixing between the first to third light-emitting regions (LA1, LA2, LA3). The first light-blocking member (BK1) may be placed in a grid shape surrounding the first to third light-emitting regions (LA1, LA2, LA3) on a plane. The first light-blocking member (BK1) may be placed in a non-overlapping manner with the first to third light-emitting regions (LA1, LA2, LA3).
[0056] The first light-blocking member (BK1) may include an organic light-blocking material and a liquid-repellent component. Here, the liquid-repellent component may be composed of a fluorine-containing monomer or a fluorine-containing polymer, and specifically may include a fluorine-containing aliphatic polycarbonate. For example, the first light-blocking member (BK1) may be composed of a black organic material containing the liquid-repellent component. The first light-blocking member (BK1) may be formed through a coating and exposure process, etc., of an organic light-blocking material containing the liquid-repellent component.
[0057] The first light-blocking member (BK1) includes a liquid-repellent component, thereby separating the first and second wavelength conversion sections (WLC1, WLC2) and the light-transmitting section (LTU) into corresponding light-emitting regions (LA1~LA3). For example, if the first and second wavelength conversion sections (WLC1, WLC2) and the light-transmitting section (LTU) are formed by an inkjet method, an ink composition may flow on the upper surface of the first light-blocking member (BK1). In this case, the first light-blocking member (BK1) includes a liquid-repellent component, thereby inducing the ink composition to flow into each light-emitting region. Thus, the first light-blocking member (BK1) can prevent the ink composition from mixing.
[0058] A first wavelength conversion unit (WLC1) may be disposed in a first light-emitting region (LA1) on a second planarization layer (41). The first wavelength conversion unit (WLC1) may be surrounded by a first light-blocking member (BK1). The first wavelength conversion unit (WLC1) may include a first base resin (BS1), a first scatterer (SCT1), and a first wavelength shifter (WLS1).
[0059] The first base resin (BS1) may include a material with a relatively high light transmittance. The first base resin (BS1) may be made of a transparent organic material. For example, the first base resin (BS1) may include at least one of organic materials such as an epoxy resin, an acrylic resin, a cardo resin, and an imide resin.
[0060] The first scatterer (SCT1) may have a refractive index different from that of the first base resin (BS1) and may form an optical interface with the first base resin (BS1). For example, the first scatterer (SCT1) may include a light-scattering material or light-scattering particles that scatter at least a portion of the transmitted light. For example, the first scatterer (SCT1) may include metal oxide particles such as titanium oxide (TiO2), zirconium oxide (ZrO2), aluminum oxide (AlxOy), indium oxide (In2O3), zinc oxide (ZnO), or tin oxide (SnO2), or organic particles such as acrylic resin or urethane resin. The first scatterer (SCT1) may scatter light in a random direction regardless of the incident direction of the incident light without substantially changing the peak wavelength of the incident light.
[0061] The first wavelength shifter (WLS1) can convert or shift the peak wavelength of incident light to the first peak wavelength. For example, the first wavelength shifter (WLS1) can convert and emit blue light provided by the light-emitting element layer (EML) into red light having a single peak wavelength in the range of 610 nm to 650 nm. The first wavelength shifter (WLS1) may be a quantum dot, a quantum rod, or a phosphor. A quantum dot may be a particulate material that emits a specific color as electrons transition from the conduction band to the valence band.
[0062] For example, quantum dots can be semiconductor nanocrystalline materials. Depending on their composition and size, quantum dots can have a specific band gap and emit light with a specific wavelength after absorbing light. Examples of semiconductor nanocrystalline quantum dots include group IV nanocrystals, group II-VI compound nanocrystals, group III-V compound nanocrystals, group IV-VI nanocrystals, or combinations thereof.
[0063] For example, a quantum dot may have a core-shell structure comprising a core containing the aforementioned nanocrystal and a shell surrounding the core. The shell of the quantum dot may serve as a protective layer to maintain semiconductor properties by preventing chemical degradation of the core, and as a charging layer to impart electrophoretic properties to the quantum dot. The shell may be a single layer or a multilayer. The interface between the core and the shell may have a concentration gradient in which the concentration of elements present in the shell decreases toward the center. The shell of the quantum dot may be composed of metal or non-metal oxides, semiconductor compounds, or combinations thereof.
[0064] The light emitted by the first wavelength shifter (WLS1) may have a Full Width of Half Maximum (FWHM) of the emission wavelength spectrum of 45 nm or less, 40 nm or less, or 30 nm or less, and the color purity and color reproducibility of the color displayed by the display device (10) can be further improved. The light emitted by the first wavelength shifter (WLS1) may be emitted in multiple directions regardless of the incident direction of the incident light. Accordingly, the side visibility of red displayed in the first emission region (LA1) can be improved.
[0065] A portion of the blue light provided by the light-emitting element layer (EML) may pass through the first wavelength conversion unit (WLC1) without being converted into red light by the first wavelength shifter (WLS1). Among the blue light provided by the light-emitting element layer (EML), the light incident on the first color filter (CF1) without being converted by the first wavelength conversion unit (WLC1) may be blocked by the first color filter (CF1). Furthermore, among the blue light provided by the light-emitting element layer (EML), the red light converted by the first wavelength conversion unit (WLC1) may pass through the first color filter (CF1) and be emitted to the outside. Therefore, the first light-emitting region (LA1) may emit red light.
[0066] The second wavelength conversion unit (WLC2) may be disposed in the second light-emitting region (LA2) on the second planarization layer (41). The second wavelength conversion unit (WLC2) may be surrounded by the first light-blocking member (BK1). The second wavelength conversion unit (WLC2) may include a second base resin (BS2), a second scatterer (SCT2), and a second wavelength shifter (WLS2).
[0067] The second base resin (BS2) may include a material with relatively high light transmittance. The second base resin (BS2) may be made of a transparent organic material. For example, the second base resin (BS2) may be made of the same material as the first base resin (BS1) or may be made of the material exemplified in the first base resin (BS1).
[0068] The second scatterer (SCT2) may have a refractive index different from that of the second base resin (BS2) and may form an optical interface with the second base resin (BS2). For example, the second scatterer (SCT2) may include a light-scattering material or light-scattering particles that scatter at least a portion of the transmitted light. For example, the second scatterer (SCT2) may be made of the same material as the first scatterer (SCT1) or may be made of the material exemplified in the first scatterer (SCT1). The second scatterer (SCT2) may scatter light in random directions regardless of the incident direction of the incident light without substantially changing the peak wavelength of the incident light.
[0069] The second wavelength shifter (WLS2) can convert or shift the peak wavelength of incident light to a second peak wavelength different from the first peak wavelength of the first wavelength shifter (WLS1). For example, the second wavelength shifter (WLS2) can convert and emit blue light provided by the light-emitting element layer (EML) into green light having a single peak wavelength in the range of 510 nm to 550 nm. The second wavelength shifter (WLS2) may be a quantum dot, a quantum rod, or a phosphor. The second wavelength shifter (WLS2) may include a material of the same nature as the material exemplified in the first wavelength shifter (WLS1). The second wavelength shifter (WLS2) may be composed of a quantum dot, a quantum rod, or a phosphor such that the wavelength conversion range of the second wavelength shifter (WLS2) is different from the wavelength conversion range of the first wavelength shifter (WLS1).
[0070] The light-transmitting portion (LTU) may be disposed in a third light-emitting region (LA3) on the second planarization layer (41). The light-transmitting portion (LTU) may be surrounded by a first light-blocking member (BK1). The light-transmitting portion (LTU) may transmit while maintaining the peak wavelength of the incident light. The light-transmitting portion (LTU) may include a third base resin (BS3) and a third scatterer (SCT3).
[0071] The third base resin (BS3) may include a material with relatively high light transmittance. The third base resin (BS3) may be made of a transparent organic material. For example, the third base resin (BS3) may be made of the same material as the first or second base resin (BS1, BS2), or may be made of the material exemplified in the first or second base resin (BS1, BS2).
[0072] The third scatterer (SCT3) may have a refractive index different from that of the third base resin (BS3) and may form an optical interface with the third base resin (BS3). For example, the third scatterer (SCT3) may include a light-scattering material or light-scattering particles that scatter at least a portion of the transmitted light. For example, the third scatterer (SCT3) may be made of the same material as the first or second scatterer (SCT1, SCT2) or may be made of the material exemplified in the first or second scatterer (SCT1, SCT2). The third scatterer (SCT3) may scatter light in random directions regardless of the incident direction of the incident light without substantially changing the peak wavelength of the incident light.
[0073] Since the wavelength conversion layer (WLCL) is placed directly on the second planarization layer (41), the display device (10) may not require a separate substrate for the first and second wavelength conversion sections (WLC1, WLC2) and the light transmission section (LTU). Accordingly, the first and second wavelength conversion sections (WLC1, WLC2) and the light transmission section (LTU) can be easily aligned with each of the first to third light-emitting regions (LA1, LA2, LA3), and the thickness of the display device (10) can be relatively reduced.
[0074] The first capping layer (CAP1) may cover the first and second wavelength conversion sections (WLC1, WLC2), the light transmission section (LTU), and the first light-blocking member (BK1). For example, the first capping layer (CAP1) may seal the first and second wavelength conversion sections (WLC1, WLC2) and the light transmission section (LTU) to prevent damage or contamination of the first and second wavelength conversion sections (WLC1, WLC2) and the light transmission section (LTU). The first capping layer (CAP1) may include an inorganic material. For example, the first capping layer (CAP1) may include at least one of silicon nitride, aluminum nitride, zirconium nitride, titanium nitride, hafnium nitride, tantalum nitride, silicon oxide, aluminum oxide, titanium oxide, tin oxide, cerium oxide, and silicon oxynitride.
[0075] A color filter layer (CFL) may be disposed on the first capping layer (CAP1). The color filter layer (CFL) may include a reflective layer (RFL), a second light-blocking member (BK2), a first color filter (CF1), and a third flattening layer (43).
[0076] The reflective layer (RFL) may be disposed overlapping the first to third light-emitting regions (LA1, LA2, LA3) and the first to third light-blocking regions (BA1, BA2, BA3) on the first capping layer (CAP1) of the wavelength conversion layer (WLCL). The reflective layer (RFL) can improve the efficiency of blue light by reflecting the blue light provided by the light-emitting element layer (EML) downwards, causing it to be re-reflected and emitted from the electrodes of the lower light-emitting element layer (EML). The reflective layer (RFL) may include a plurality of first holes (HO1) that overlap with the first to third light-emitting regions (LA1, LA2, LA3). The first to third light-emitting regions (LA1, LA2, LA3) are regions where light is emitted to the outside, and light can be emitted to the outside through the plurality of first holes (HO1). The reflective layer (RFL) is also placed in the region overlapping with the first to third light-emitting regions (LA1, LA2, LA3), thereby further improving the efficiency of blue light.
[0077] The second light-blocking member (BK2) may be placed overlappingly on the reflective layer (RFL) with the first to third light-emitting regions (LA1, LA2, LA3) and the first to third light-blocking regions (BA1, BA2, BA3). The second light-blocking member (BK2) may overlap in the thickness direction with the first light-blocking member (BK1), the reflective layer (RFL), or the second pattern (BNL2). The second light-blocking member (BK2) can block the transmission of light. The second light-blocking member (BK2) can improve color reproduction by preventing light from interfering and mixing between the first to third light-emitting regions (LA1, LA2, LA3). Additionally, the second light-blocking member (BK2) can reduce external light reflectivity by absorbing light incident from the outside.
[0078] The second light-blocking member (BK2) may include a plurality of second holes (HO2) that overlap with the first to third light-emitting regions (LA1, LA2, LA3), just like the reflective layer (RFL). The first to third light-emitting regions (LA1, LA2, LA3) are regions where light is emitted to the outside, and light can be emitted to the outside through the plurality of second holes (HO2).
[0079] A first color filter (CF1) may be placed in a first capping layer (CAP1), a first light-emitting region (LA1), and a second light-emitting region (LA2). The first color filter (CF1) may be surrounded by a reflective layer (RFL) and a second light-blocking member (BK2), and may cover at least a portion of the reflective layer (RFL) and the second light-blocking member (BK2) in the first light-emitting region (LA1) and the second light-emitting region (LA2). The first color filter (CF1) may overlap with the first wavelength converter (WLC1) and the second wavelength converter (WLC2) in the thickness direction.
[0080] The first color filter (CF1) can prevent mixing of blue light provided from the light-emitting element layer (EML) with light that has been converted into a first color light (e.g., red light) and a second color light (e.g., green light), respectively, by passing through the first wavelength conversion unit (WLC1) and the second wavelength conversion unit (WLC2). For example, the first color filter (CF1) blocks blue light that is not converted in the first wavelength conversion unit (WLC1) and blocks blue light that is not converted in the second wavelength conversion unit (WLC2). By doing so, the first color filter (CF1) can block blue light in the first light-emitting region (LA1) and the second light-emitting region (LA2) to emit pure first color light (e.g., red light) and second color light (e.g., green light).
[0081] The first color filter (CF1) is positioned overlappingly in the first light-emitting region (LA1) and the second light-emitting region (LA2), respectively, and is positioned non-overlappingly with the third light-emitting region (LA3), thereby enabling the emission of a third color light (e.g., blue light) emitted through the light-transmitting unit (LTU) in the third light-emitting region (LA3). The first color filter (CF1) can absorb a portion of the light entering from outside the display device (10) to reduce reflected light caused by external light.
[0082] Since the first color filter (CF1) is placed directly on the first capping layer (CAP1) of the wavelength conversion layer (WLCL), the display device (10) may not require a separate substrate for the first color filter (CF1). Therefore, the thickness of the display device (10) can be relatively reduced.
[0083] A third flattening layer (43) may be disposed on the second light-blocking member (BK2), the first color filter (CF1), and the first capping layer (CAP1). The third flattening layer (43) may flatten the upper portion of the second light-blocking member (BK2), the first color filter (CF1), and the first capping layer (CAP1). The third flattening layer (43) may be made of the same material as the second flattening layer (41) or may be made of the material exemplified in the second flattening layer (41).
[0084] An anti-reflection member (45) may be disposed on the third flattening layer (43). The anti-reflection member (45) can absorb light incident from the outside to prevent the display quality from deteriorating due to the reflection of external light. In an exemplary embodiment, the anti-reflection member (45) may include a dye capable of absorbing light other than light of the first to third colors (e.g., red, green, and blue) to prevent the reflection of external light.
[0085] Hereinafter, the transistor layer (TFTL) and the light-emitting element layer (EML) will be described in detail through the planar and cross-sectional structures of a pixel of a display device (10) according to one embodiment.
[0086] FIG. 3 is a plan view showing one pixel of a display device according to one embodiment.
[0087] Referring to FIG. 3, each of the plurality of pixels (PX) may include a plurality of subpixels (PXn, where n is an integer from 1 to 3). For example, one pixel (PX) may include a first subpixel (PX1), a second subpixel (PX2), and a third subpixel (PX3). The first subpixel (PX1), the second subpixel (PX2), and the third subpixel (PX3) may emit light of a third color. For example, the first subpixel (PX1), the second subpixel (PX2), and the third subpixel (PX3) may each emit blue light. However, not limited thereto, the first subpixel (PX1) may emit light of a first color, the second subpixel (PX2) may emit light of a second color, and the third subpixel (PX3) may emit light of a third color. For example, the first color may be blue, the second color may be green, and the third color may be red. Additionally, while FIG. 3 illustrates a pixel (PX) comprising three subpixels (PXn), it is not limited thereto, and the pixel (PX) may comprise a larger number of subpixels (PXn).
[0088] Each subpixel (PXn) of the display device (10) may include a light-emitting part (EMA) and a non-light-emitting part (not shown). The light-emitting part (EMA) is an area where a light-emitting element (30) is placed and light of a specific wavelength range is emitted, and the non-light-emitting part may be an area where a light-emitting element (30) is not placed and light emitted from the light-emitting element (30) does not reach, so light is not emitted. The light-emitting part (EMA) may include an area where a light-emitting element (30) is placed and an area adjacent to the light-emitting element (30) where light emitted from the light-emitting element (30) is emitted.
[0089] Not limited thereto, the light-emitting part (EMA) may also include an area where light emitted from a light-emitting element (30) is reflected or refracted by another member and emitted. A plurality of light-emitting elements (30) are arranged in each sub-pixel (PXn), and a light-emitting part may be formed by including the area where they are arranged and an adjacent area. The light-emitting part (EMA) corresponds to the aforementioned light-emitting areas (LA1, LA2, LA3), and the non-light-emitting part may correspond to the aforementioned light-blocking areas (BA1, BA2, BA3).
[0090] Additionally, each subpixel (PXn) may include a cutting portion (CBA) disposed in a non-emissive portion. The cutting portion (CBA) may be disposed on one side of the second direction (DR2) of the emitting portion (EMA). The cutting portion (CBA) may be disposed between the emitting portions (EMA) of the subpixels (PXn) adjacent in the second direction (DR2). A plurality of emitting portions (EMA) and cutting portions (CBA) may be arranged in the display area (DPA) of the display device (10). For example, a plurality of emitting portions (EMA) and cutting portions (CBA) may be arranged repeatedly in the first direction (DR1), while the emitting portion (EMA) and cutting portion (CBA) may be arranged alternately in the second direction (DR2). Furthermore, the spacing of the cutting portions (CBA) in the first direction (DR1) may be smaller than the spacing of the emitting portion (EMA) in the first direction (DR1). A second pattern (BNL2) is disposed between the cutting sections (CBA) and the emitting sections (EMA), and the spacing between them may vary depending on the width of the second pattern (BNL2). A emitting element (30) is not disposed in the cutting section (CBA) so that light is not emitted, but some of the electrodes (21, 22) disposed in each subpixel (PXn) may be disposed therein. The electrodes (21, 22) disposed in each subpixel (PXn) may be disposed separated from each other in the cutting section (CBA).
[0091] FIG. 4 is a cross-sectional view taken along the Q1-Q1' line, Q2-Q2' line and Q3-Q3' line of FIG. 3. FIG. 4 illustrates a cross-section across both ends of a light-emitting element (30) placed in the first subpixel (PX1) of FIG. 3.
[0092] Referring to FIG. 4 in conjunction with FIG. 3, the display device (10) may include a substrate (11) and a semiconductor layer, a plurality of conductive layers, and a plurality of insulating layers disposed on the substrate (11). The semiconductor layer, the conductive layer, and the insulating layers may each constitute a circuit layer and a light-emitting element layer of the display device (10).
[0093] A light-blocking layer (BML) may be placed on a substrate (11). The light-blocking layer (BML) may be placed to overlap with the active layer (ACT) of the first transistor (T1) of the display device (10). The light-blocking layer (BML) may include a material that blocks light, thereby preventing light from being incident on the active layer (ACT) of the first transistor (T1). For example, the light-blocking layer (BML) may be formed of an opaque metallic material that blocks the transmission of light. However, it is not limited thereto, and in some cases, the light-blocking layer (BML) may be omitted. Additionally, the light-blocking layer (BML) may be electrically connected to the source electrode (SE) to suppress changes in the voltage of the transistor. Furthermore, the light-blocking layer (BML) may be used for wiring, such as power wiring, data wiring, or gate wiring.
[0094] The buffer layer (12) may be disposed over the entire surface of the substrate (11), including a light-blocking layer (BML). The buffer layer (12) is formed on the substrate (11) to protect the first transistors (T1) of the pixel (PX) from moisture penetrating through the substrate (11), which is susceptible to moisture permeability, and can perform a surface flattening function. The buffer layer (12) may be composed of a plurality of inorganic layers that are alternately stacked. For example, the buffer layer (12) may be formed as a multilayer in which inorganic layers comprising at least one of silicon oxide (SiOx), silicon nitride (SiNx), and silicon oxynitride (SiOxNy) are alternately stacked.
[0095] The semiconductor layer may be placed on the buffer layer (12). The semiconductor layer may include the active layer (ACT) of the first transistor (T1). These may be arranged to partially overlap with the gate electrode (G1) of the first gate conductive layer described later.
[0096] Meanwhile, the drawing shows only the first transistor (T1) among the transistors included in the subpixel (PXn) of the display device (10), but is not limited thereto. The display device (10) may include a larger number of transistors. For example, the display device (10) may include two or three transistors by including one or more additional transistors in addition to the first transistor (T1) for each subpixel (PXn).
[0097] The semiconductor layer may include polycrystalline silicon, single-crystal silicon, oxide semiconductors, etc. When the semiconductor layer includes an oxide semiconductor, each active layer (ACT) may include a plurality of conductive regions (ACTa, ACTb) and channel regions (ACTc) between them. The oxide semiconductor may be an oxide semiconductor containing indium (In). For example, the oxide semiconductor may be indium-tin oxide (ITO), indium-zinc oxide (IZO), indium-gallium oxide (IGO), indium-zinc-tin oxide (IZTO), indium-gallium-tin oxide (IGTO), indium-gallium-zinc oxide (IGZO), indium-gallium-zinc-tin oxide (IGZTO), etc.
[0098] In another embodiment, the semiconductor layer may include polycrystalline silicon. Polycrystalline silicon can be formed by crystallizing amorphous silicon, in which case the conductive regions of the active layer (ACT) may each be doped regions doped with impurities.
[0099] The first gate insulating layer (13) may be disposed on the semiconductor layer and the buffer layer (12). The first gate insulating layer (13) may be disposed on the buffer layer (12) including the semiconductor layer. The first gate insulating layer (13) may function as a gate insulating film for each transistor. The first gate insulating layer (13) may be composed of an inorganic layer including an inorganic material, such as silicon oxide (SiOx), silicon nitride (SiNx), or silicon oxynitride (SiOxNy), or may be formed in a stacked structure.
[0100] A first gate conductive layer may be disposed on a first gate insulating layer (13). The first gate conductive layer may include a gate electrode (G1) of a first transistor (T1) and a first capacitive electrode (CSE1) of a storage capacitor. The gate electrode (G1) may be disposed to overlap in the thickness direction with the channel region (ACTc) of the active layer (ACT). The first capacitive electrode (CSE1) may be disposed to overlap in the thickness direction with a second capacitive electrode (CSE2) described later. In one embodiment, the first capacitive electrode (CSE1) may be connected to the gate electrode (G1) and integrated. The first capacitive electrode (CSE1) may be disposed to overlap in the thickness direction with the second capacitive electrode (CSE2), and a storage capacitor may be formed between them.
[0101] The first gate conductive layer may be formed as a single layer or a multilayer composed of any one of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu), or an alloy thereof. However, it is not limited thereto.
[0102] The first interlayer insulating layer (15) may be disposed on the first gate conductive layer. The first interlayer insulating layer (15) may function as an insulating film between the first gate conductive layer and other layers disposed thereon. Additionally, the first interlayer insulating layer (15) may be disposed to cover the first gate conductive layer and perform a protective function thereon. The first interlayer insulating layer (15) may be composed of an inorganic layer including an inorganic material, such as silicon oxide (SiOx), silicon nitride (SiNx), or silicon oxynitride (SiOxNy), or may be formed in a stacked structure.
[0103] The first data conductive layer may be disposed on the first interlayer insulating layer (15). The first data conductive layer may include the source electrode (SE) and drain electrode (DE) of the first transistor (T1), a data line (DTL), and a second capacitance electrode (CSE2).
[0104] The source electrode (SE) and drain electrode (DE) of the first transistor (T1) can each come into contact with the doping regions (ACTa, ACTb) of the active layer (ACT) through a contact hole penetrating the first interlayer insulating layer (15) and the first gate insulating layer (13). Additionally, the source electrode (SE) of the first transistor (T1) can be electrically connected to the light-blocking layer (BML) through another contact hole.
[0105] The data line (DTL) can apply a data signal to another transistor (not shown) included in the display device (10). Although not shown in the drawing, the data line (DTL) can be connected to the source / drain electrodes of another transistor to transmit the signal applied from the data line (DTL).
[0106] The second capacitance electrode (CSE2) may be positioned to overlap the first capacitance electrode (CSE1) in the thickness direction. In one embodiment, the second capacitance electrode (CSE2) may be integrated and connected with the source electrode (SE).
[0107] The first data conductive layer may be formed as a single layer or a multilayer composed of any one of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu), or an alloy thereof. However, it is not limited thereto.
[0108] The second interlayer insulating layer (17) may be disposed on the first data conductive layer. The second interlayer insulating layer (17) may function as an insulating film between the first data conductive layer and other layers disposed thereon. Additionally, the second interlayer insulating layer (17) may cover the first data conductive layer and perform the function of protecting the first data conductive layer. The second interlayer insulating layer (17) may be composed of an inorganic layer including inorganic materials, such as silicon oxide (SiOx), silicon nitride (SiNx), and silicon oxynitride (SiOxNy), or may be formed in a stacked structure.
[0109] The second data conductive layer may be disposed on the second interlayer insulating layer (17). The second data conductive layer may include a first voltage line (VL1), a second voltage line (VL2), and a first conductive pattern (CDP). A high potential voltage (or a first power supply voltage) supplied to the first transistor (T1) may be applied to the first voltage line (VL1), and a low potential voltage (or a second power supply voltage) supplied to the second electrode (22) may be applied to the second voltage line (VL2). Additionally, an alignment signal required to align the light-emitting element (30) during the manufacturing process of the display device (10) may be applied to the second voltage line (VL2).
[0110] The first conductive pattern (CDP) can be connected to the second capacitance electrode (CSE2) through a contact hole formed in the second interlayer insulating layer (17). The second capacitance electrode (CSE2) can be integrated with the source electrode (SE) of the first transistor (T1), and the first conductive pattern (CDP) can be electrically connected to the source electrode (SE). The first conductive pattern (CDP) also contacts the first electrode (21) described later, and the first transistor (T1) can transmit the first power supply voltage applied from the first voltage wiring (VL1) to the first electrode (21) through the first conductive pattern (CDP). Meanwhile, although the drawing shows the second data conductive layer including one second voltage wiring (VL2) and one first voltage wiring (VL1), it is not limited thereto. The second data conductive layer may include a larger number of first voltage wirings (VL1) and second voltage wirings (VL2). However, it is not limited to this, and the first data conductive layer may serve to transmit signals such as power supply voltage, in which case the second data conductive layer may be omitted.
[0111] The second data conductive layer may be formed as a single layer or a multilayer composed of any one of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu), or an alloy thereof. However, it is not limited thereto.
[0112] The first planarization layer (19) may be disposed on the second data conductive layer. The first planarization layer (19) may include an organic insulating material, such as polyimide (PI), and may perform a surface planarization function.
[0113] A plurality of first patterns (BNL1), a plurality of electrodes (21, 22), a light-emitting element (30), a plurality of connecting electrodes (CNE1, CNE2) and a second pattern (BNL2) may be disposed on the first flattening layer (19). Additionally, a plurality of insulating layers (PAS1, PAS2, PAS3, PAS4) may be disposed on the first flattening layer (19).
[0114] A plurality of first patterns (BNL1) may be placed directly on the first planarization layer (19). A plurality of first patterns (BNL1) may have a shape that extends in a second direction (DR2) within each subpixel (PXn), but may not extend to other adjacent subpixels (PXn) in the second direction (DR2) and may be placed within the light-emitting part (EMA). Additionally, a plurality of first patterns (BNL1) may be spaced apart from each other in the first direction (DR1), and a light-emitting element (30) may be placed between them. A plurality of first patterns (BNL1) may be placed in each subpixel (PXn) to form a linear pattern in the display area (DPA) of the display device (10). Although two first patterns (BNL1) are shown in the drawing, they are not limited thereto. A larger number of first patterns (BNL1) may be placed depending on the number of electrodes (21, 22).
[0115] The first pattern (BNL1) may have a structure in which at least a portion protrudes with respect to the upper surface of the first flattening layer (19). The protruding portion of the first pattern (BNL1) may have an inclined side, and light emitted from the light-emitting element (30) may be reflected from the electrodes (21, 22) placed on the first pattern (BNL1) and emitted in the upward direction of the first flattening layer (19). The first pattern (BNL1) may provide an area where the light-emitting element (30) is placed and may also function as a reflective barrier that reflects light emitted from the light-emitting element (30) in the upward direction. The side of the first pattern (BNL1) may be inclined in a linear shape, but is not limited thereto, and the first pattern (BNL1) may have a shape of a semicircle or semi-ellipse with a curved outer surface. The first patterns (BNL1) may include an organic insulating material such as polyimide (PI), but are not limited thereto.
[0116] A plurality of electrodes (21, 22) may be disposed on a first pattern (BNL1) and a first flattening layer (19). The plurality of electrodes (21, 22) may include a first electrode (21) and a second electrode (22). The first electrode (21) and the second electrode (22) extend in a second direction (DR2), and may be disposed so as to be spaced apart from each other in a first direction (DR1).
[0117] The first electrode (21) and the second electrode (22) may each extend in a second direction (DR2) within a subpixel (PXn) and be separated from other electrodes (21, 22) at a cutting portion (CBA). For example, a cutting portion (CBA) may be placed between the light-emitting portions (EMA) of subpixels (PXn) adjacent in the second direction (DR2), and the first electrode (21) and the second electrode (22) may be separated at the cutting portion (CBA) from other first electrodes (21) and second electrodes (22) placed in subpixels (PXn) adjacent in the second direction (DR2). However, this is not limited thereto, and some electrodes (21, 22) may be placed extending beyond subpixels (PXn) adjacent in the second direction (DR2) without being separated for each subpixel (PXn), or only one of the first electrode (21) or the second electrode (22) may be separated.
[0118] The first electrode (21) may be electrically connected to the first transistor (T1) through the first contact hole (CT1), and the second electrode (22) may be electrically connected to the second voltage wiring (VL2) through the second contact hole (CT2). For example, the first electrode (21) may contact the first conductive pattern (CDP) through the first contact hole (CT1) penetrating the first flattening layer (19) in the portion extending in the first direction (DR1) of the second pattern (BNL2). The second electrode (22) may also contact the second voltage wiring (VL2) through the second contact hole (CT2) penetrating the first flattening layer (19) in the portion extending in the first direction (DR1) of the second pattern (BNL2). However, it is not limited thereto. In another embodiment, the first contact hole (CT1) and the second contact hole (CT2) may be placed within the light-emitting part (EMA) surrounded by the second pattern (BNL2) so as not to overlap with the second pattern (BNL2). In yet another embodiment, the second electrode (22) may be in direct contact with the first data wiring layer to apply voltage.
[0119] In the drawing, it is illustrated that one first electrode (21) and one second electrode (22) are arranged for each subpixel (PXn), but this is not limited thereto, and the number of first electrodes (21) and second electrodes (22) arranged for each subpixel (PXn) may be greater. Additionally, the first electrode (21) and the second electrode (22) arranged for each subpixel (PXn) may not necessarily have a shape that extends in one direction, and the first electrode (21) and the second electrode (22) may be arranged in various structures. For example, the first electrode (21) and the second electrode (22) may have a partially curved or bent shape, and one electrode may be arranged to surround the other electrode.
[0120] The first electrode (21) and the second electrode (22) may each be placed directly on the first patterns (BNL1). The first electrode (21) and the second electrode (22) may each be formed to have a width greater than that of the first pattern (BNL1). For example, the first electrode (21) and the second electrode (22) may each be placed to cover the outer surface of the first pattern (BNL1). The first electrode (21) and the second electrode (22) are each placed on the side of the first pattern (BNL1), and the gap between the first electrode (21) and the second electrode (22) may be narrower than the gap between the first patterns (BNL1). Additionally, at least a portion of the first electrode (21) and the second electrode (22) may be placed directly on the first flattening layer (19) so that they are placed on the same plane. However, they are not limited thereto. In some cases, the width of each electrode (21, 22) may be smaller than that of the first pattern (BNL1). However, each electrode (21, 22) may be arranged to cover at least one side of the first pattern (BNL1) to reflect light emitted from the light-emitting element (30).
[0121] Each electrode (21, 22) may include a highly reflective conductive material. For example, each electrode (21, 22) may include a metal such as silver (Ag), copper (Cu), or aluminum (Al) as a highly reflective material, or an alloy including aluminum (Al), nickel (Ni), or lanthanum (La). Each electrode (21, 22) may reflect light emitted from the light-emitting element (30) and traveling toward the side of the first pattern (BNL1) toward the upper direction of each subpixel (PXn).
[0122] However, not limited thereto, each electrode (21, 22) may further include a transparent conductive material. For example, each electrode (21, 22) may include a material such as ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), ITZO (Indium Tin-Zinc Oxide), etc. In some embodiments, each electrode (21, 22) may have a structure in which a transparent conductive material and a highly reflective metal layer are each stacked one or more times, or may be formed as a single layer including these. For example, each electrode (21, 22) may have a stacked structure such as ITO / Silver(Ag) / ITO / , ITO / Ag / IZO, or ITO / Ag / ITZO / IZO.
[0123] A plurality of electrodes (21, 22) are electrically connected to light-emitting elements (30), and a predetermined voltage may be applied so that the light-emitting elements (30) emit light. A plurality of electrodes (21, 22) are electrically connected to the light-emitting elements (30) through connecting electrodes (CNE1, CNE2), and an electrical signal applied to the electrodes (21, 22) can be transmitted to the light-emitting elements (30) through the connecting electrodes (CNE1, CNE2).
[0124] Either one of the first electrode (21) and the second electrode (22) may be electrically connected to the anode electrode of the light-emitting element (30), and the other may be electrically connected to the cathode electrode of the light-emitting element (30). However, this is not limited thereto, and the opposite case may also occur.
[0125] Additionally, each electrode (21, 22) may be utilized to form an electric field within a subpixel (PXn) to align the light-emitting element (30). The light-emitting element (30) may be positioned between the first electrode (21) and the second electrode (22) by means of an electric field formed on the first electrode (21) and the second electrode (22). The light-emitting element (30) of the display device (10) may be sprayed onto the electrodes (21, 22) through an inkjet printing process. When ink containing the light-emitting element (30) is sprayed onto the electrodes (21, 22), an alignment signal is applied to the electrodes (21, 22) to generate an electric field. The light-emitting element (30) dispersed in the ink may be aligned on the electrodes (21, 22) by receiving a dielectrophoretic force from the electric field generated on the electrodes (21, 22).
[0126] A first insulating layer (PAS1) may be disposed on the first flattening layer (19). The first insulating layer (PAS1) may be disposed to cover the first patterns (BNL1), and the first electrode (21) and the second electrode (22). The first insulating layer (PAS1) can protect the first electrode (21) and the second electrode (22) while simultaneously insulating them from each other. Additionally, it may prevent the light-emitting element (30) disposed on the first insulating layer (PAS1) from being damaged by direct contact with other components.
[0127] In one embodiment, the first insulating layer (PAS1) may include an opening (OP) that partially exposes the first electrode (21) and the second electrode (22). Each opening (OP) may partially expose a portion of each electrode (21, 22) that is positioned on the upper surface of the first pattern (BNL1). Some of the connecting electrodes (CNE1, CNE2) may come into contact with each electrode (21, 22) exposed through the opening (OP).
[0128] The first insulating layer (PAS1) may have a step formed such that a portion of its upper surface is sunken between the first electrode (21) and the second electrode (22). For example, as the first insulating layer (PAS1) is positioned to cover the first electrode (21) and the second electrode (22), its upper surface may be stepped according to the shape of the electrodes (21, 22) positioned below it. However, it is not limited thereto.
[0129] The second pattern (BNL2) may be placed on the first insulating layer (PAS1). The second pattern (BNL2) may be placed in a grid pattern across the entire front of the display area (DPA), including portions extending in the first direction (DR1) and the second direction (DR2) in a planar manner. The second pattern (BNL2) may be placed across the boundaries of each subpixel (PXn) to distinguish neighboring subpixels (PXn).
[0130] Additionally, the second pattern (BNL2) is positioned to surround the light-emitting portion (EMA) and the cutting portion (CBA) placed for each subpixel (PXn), thereby distinguishing them. The first electrode (21) and the second electrode (22) can be extended in the second direction (DR2) and positioned across the portion of the second pattern (BNL2) that extends in the first direction (DR1). The portion of the second pattern (BNL2) that extends in the second direction (DR2) may have a greater width between the portions of the light-emitting portions (EMA) than the portion between the cutting portions (CBA). Accordingly, the spacing between the cutting portions (CBA) may be smaller than the spacing between the light-emitting portions (EMA).
[0131] The second pattern (BNL2) may be formed to have a greater height than the first bank (BNL1). The second pattern (BNL2) can prevent ink from overflowing into adjacent subpixels (PXn) during the inkjet printing process of the manufacturing process of the display device (10), thereby separating the inks in which different light-emitting elements (30) are dispersed for each subpixel (PXn) so that they do not mix with each other. The second pattern (BNL2) may include polyimide (PI) as in the first pattern (BNL1), but is not limited thereto.
[0132] A light-emitting element (30) may be disposed on a first insulating layer (PAS1). A plurality of light-emitting elements (30) may be spaced apart from each other along a second direction (DR2) in which each electrode (21, 22) is extended and may be aligned substantially parallel to each other. The light-emitting element (30) may have a shape that extends in one direction, and the direction in which each electrode (21, 22) is extended and the direction in which the light-emitting element (30) is extended may be substantially perpendicular. However, this is not limited thereto, and the light-emitting element (30) may be disposed obliquely rather than perpendicular to the direction in which each electrode (21, 22) is extended.
[0133] The light-emitting elements (30) placed in each subpixel (PXn) may include a light-emitting layer ('36' in FIG. 5) containing different materials and emit light of different wavelengths to the outside. Accordingly, light of the first color, the second color, and the third color may be emitted from the first subpixel (PX1), the second subpixel (PX2), and the third subpixel (PX3), respectively. However, this is not limited thereto, and each subpixel (PXn) may include the same type of light-emitting element (30) and emit light of substantially the same color.
[0134] The light-emitting element (30) may have both ends placed on each electrode (21, 22) between the first patterns (BNL1). The extended length of the light-emitting element (30) is longer than the gap between the first electrode (21) and the second electrode (22), and both ends of the light-emitting element (30) may be placed on the first electrode (21) and the second electrode (22), respectively. For example, the light-emitting element (30) may be placed such that one end is placed on the first electrode (21) and the other end is placed on the second electrode (22).
[0135] A plurality of layers of the light-emitting element (30) may be arranged in a direction perpendicular to the upper surface of the substrate (11) or the first flattening layer (19). The light-emitting element (30) may be arranged such that one extended direction is parallel to the upper surface of the first flattening layer (19), and a plurality of semiconductor layers included in the light-emitting element (30) may be arranged sequentially along a direction parallel to the upper surface of the first flattening layer (19). However, this is not limited thereto, and if the light-emitting element (30) has a different structure, a plurality of semiconductor layers may be arranged in a direction perpendicular to the upper surface of the first flattening layer (19).
[0136] Both ends of the light-emitting element (30) may each come into contact with connecting electrodes (CNE1, CNE2). For example, the light-emitting element (30) may not have an insulating film ('38' in FIG. 5) formed on the extended one-way end surface, and a portion of the semiconductor layer ('31', '32' in FIG. 5) or electrode layer ('37' in FIG. 5) may be exposed, and the exposed semiconductor layer ('31', '32' in FIG. 5) or electrode layer ('37' in FIG. 5) may come into contact with the connecting electrodes (CNE1, CNE2). However, not limited thereto, the light-emitting element (30) may have at least a portion of the insulating film (38) removed so that the sides of both ends of the semiconductor layer ('31', '32' in FIG. 5) are partially exposed. The side of the exposed semiconductor layer ('31', '32' in FIG. 5) may come into direct contact with the connecting electrode (CNE1, CNE2).
[0137] The second insulating layer (PAS2) may be partially disposed on the light-emitting element (30). For example, the second insulating layer (PAS2) may be disposed on the light-emitting element (30) with a width smaller than the length of the light-emitting element (30) so as to surround the light-emitting element (30) and expose both ends of the light-emitting element (30). The second insulating layer (PAS2) may be disposed to cover the light-emitting element (30), electrodes (21, 22), and the first insulating layer (PAS1) during the manufacturing process of the display device (10), and then removed to expose both ends of the light-emitting element (30). The second insulating layer (PAS2) may be disposed extending in a second direction (DR2) on the first insulating layer (PAS1) in a planar manner to form a linear or island pattern within each subpixel (PXn). The second insulating layer (PAS2) can protect the light-emitting element (30) and at the same time fix the light-emitting element (30) during the manufacturing process of the display device (10).
[0138] A plurality of connecting electrodes (CNE1, CNE2) and a third insulating layer (PAS3) may be disposed on the second insulating layer (PAS2).
[0139] A plurality of connecting electrodes (CNE1, CNE2) may have a shape extending in one direction and may be disposed on each electrode (21, 22). The connecting electrodes (CNE1, CNE2) may include a first connecting electrode (CNE1) disposed on the first electrode (21) and a second connecting electrode (CNE2) disposed on the second electrode (22). Each connecting electrode (CNE1, CNE2) may be disposed spaced apart from or facing each other. For example, the first connecting electrode (CNE1) and the second connecting electrode (CNE2) may be disposed on the first electrode (21) and the second electrode (22), respectively, and spaced apart from each other in a first direction (DR1). Each connecting electrode (CNE1, CNE2) may form a stripe-shaped pattern within the light-emitting portion (EMA) of each subpixel (PXn).
[0140] A plurality of connecting electrodes (CNE1, CNE2) can each contact a light-emitting element (30). The first connecting electrode (CNE1) can contact one end of the light-emitting element (30), and the second connecting electrode (CNE2) can contact the other end of the light-emitting element (30). A semiconductor layer is exposed on both end surfaces of the light-emitting element (30) in an extended direction, and each connecting electrode (CNE1, CNE2) can be electrically connected to the semiconductor layer of the light-emitting element (30) by contacting it. One side of the connecting electrode (CNE1, CNE2) that contacts both ends of the light-emitting element (30) can be disposed on the second insulating layer (PAS2). Additionally, the first connecting electrode (CNE1) may contact the first electrode (21) through an opening (OP) that exposes a portion of the upper surface of the first electrode (21), and the second connecting electrode (CNE2) may contact the second electrode (22) through an opening (OP) that exposes a portion of the upper surface of the second electrode (22).
[0141] Each connecting electrode (CNE1, CNE2) may have a width measured in one direction that is smaller than the width measured in one direction of each electrode (21, 22). The connecting electrodes (CNE1, CNE2) may be arranged to contact one end and the other end of the light-emitting element (30) and simultaneously cover a portion of the upper surface of the first electrode (21) and the second electrode (22). However, not limited thereto, the connecting electrodes (CNE1, CNE2) may be formed with a width larger than that of the electrodes (21, 22) to cover both sides of the electrodes (21, 22).
[0142] The connecting electrodes (CNE1, CNE2) may include a transparent conductive material. For example, they may include ITO, IZO, ITZO, aluminum (Al), etc. Light emitted from the light-emitting element (30) may pass through the connecting electrodes (CNE1, CNE2) and proceed toward the electrodes (21, 22). However, it is not limited thereto.
[0143] In the drawing, two connecting electrodes (CNE1, CNE2) are shown arranged in one subpixel (PXn), but are not limited thereto. The number of each connecting electrode (CNE1, CNE2) may vary depending on the number of electrodes (21, 22) arranged in each subpixel (PXn).
[0144] The third insulating layer (PAS3) may be positioned to cover the first connecting electrode (CNE1). The third insulating layer (PAS3) may be positioned to cover one side on which the first connecting electrode (CNE1) is positioned relative to the second insulating layer (PAS2), including the first connecting electrode (CNE1). For example, the third insulating layer (PAS3) may be positioned to cover the first insulating layers (PAS1) positioned on the first connecting electrode (CNE1) and the first electrode (21). This positioning may be formed by a process in which the insulating material layer constituting the third insulating layer (PAS3) is positioned entirely on the light-emitting part (EMA), and then a portion of the insulating material layer is removed to form the second connecting electrode (CNE2). In the above process, the insulating material layer forming the third insulating layer (PAS3) can be removed together with the insulating material layer forming the second insulating layer (PAS2), and one side of the third insulating layer (PAS3) can be aligned with one side of the second insulating layer (PAS2). One side of the second connecting electrode (CNE2) is placed on the third insulating layer (PAS3), and can be mutually insulated from the first connecting electrode (CNE1) with this in between.
[0145] The fourth insulating layer (PAS4) may be placed over the entire display area (DPA) of the substrate (11). The fourth insulating layer (PAS4) may function to protect the external environment of the components placed on the substrate (11). However, the fourth insulating layer (PAS4) may be omitted.
[0146] Each of the above-described first insulating layer (PAS1), second insulating layer (PAS2), third insulating layer (PAS3), and fourth insulating layer (PAS4) may include an inorganic insulating material or an organic insulating material. For example, the first insulating layer (PAS1), second insulating layer (PAS2), third insulating layer (PAS3), and fourth insulating layer (PAS4) may include inorganic insulating materials such as silicon oxide (SiOx), silicon nitride (SiNx), silicon oxynitride (SiOxNy), aluminum oxide (AlxOy), aluminum nitride (AlN), etc. Alternatively, these may include, as organic insulating materials, acrylic resin, epoxy resin, phenolic resin, polyamide resin, polyimide resin, unsaturated polyester resin, polyphenylene resin, polyphenylene sulfide resin, benzocyclobutene, cardo resin, siloxane resin, silsesquioxane resin, polymethyl methacrylate, polycarbonate, polymethyl methacrylate-polycarbonate synthetic resin, etc. However, they are not limited thereto.
[0147] FIG. 5 is a schematic diagram of a light-emitting element according to one embodiment.
[0148] Referring to FIG. 5, the light-emitting element (30) is a particle-shaped element and may be a rod or cylindrical shape having a predetermined aspect ratio. The light-emitting element (30) may have a size ranging from a nanometer scale (1 nm or more and less than 1 µm) to a micrometer scale (1 µm or more and less than 1 mm). In one embodiment, the light-emitting element (30) may have both a diameter and a length of a nanometer scale or both of micrometer scales. In some other embodiments, the diameter of the light-emitting element (30) may have a nanometer scale, while the length of the light-emitting element (30) may have a micrometer scale. In some embodiments, some of the light-emitting elements (30) may have a diameter and / or length of a nanometer scale, while other parts of the light-emitting elements (30) may have a diameter and / or length of a micrometer scale.
[0149] In one embodiment, the light-emitting element (30) may be an inorganic light-emitting diode. Specifically, the light-emitting element (30) may include a semiconductor layer doped with any conductivity type (e.g., p-type or n-type) impurity. The semiconductor layer receives an electrical signal applied from an external power source and can emit it as light of a specific wavelength range.
[0150] A light-emitting element (30) according to one embodiment may include a first semiconductor layer (31), an active layer (33), a second semiconductor layer (32), and an electrode layer (37) that are sequentially stacked in the longitudinal direction. The light-emitting element may further include an insulating film (38) covering the outer surface of the first semiconductor layer (31), the second semiconductor layer (32), and the active layer (33).
[0151] The first semiconductor layer (31) may be an n-type semiconductor. When the light-emitting element (30) emits light in the blue wavelength range, the first semiconductor layer (31) may include a semiconductor material having the chemical formula AlxGayIn1-x-yN (0≤x≤1, 0≤y≤1, 0≤x+y≤1). For example, it may be one or more of n-type doped AlGaInN, GaN, AlGaN, InGaN, AlN, and InN. The first semiconductor layer (31) may be doped with an n-type dopant, and the n-type dopant may be Si, Ge, Sn, etc. For example, the first semiconductor layer (31) may be n-GaN doped with n-type Si. The length of the first semiconductor layer (31) may be in the range of 1.5 μm to 5 μm, but is not limited thereto.
[0152] The second semiconductor layer (32) may be disposed on the light-emitting layer (36) described later. The second semiconductor layer (32) may be a p-type semiconductor, and when the light-emitting element (30) emits light in the blue or green wavelength range, the second semiconductor layer (32) may include a semiconductor material having the chemical formula AlxGayIn1-x-yN (0≤x≤1, 0≤y≤1, 0≤x+y≤1). For example, it may be one or more of p-type doped AlGaInN, GaN, AlGaN, InGaN, AlN, and InN. The second semiconductor layer (32) may be doped with a p-type dopant, and the p-type dopant may be Mg, Zn, Ca, Se, Ba, etc. For example, the second semiconductor layer (32) may be p-GaN doped with p-type Mg. The length of the second semiconductor layer (32) may be in the range of 0.05㎛ to 0.10㎛, but is not limited thereto.
[0153] Meanwhile, the drawing shows the first semiconductor layer (31) and the second semiconductor layer (32) as being composed of a single layer, but is not limited thereto. Depending on the material of the light-emitting layer (36), the first semiconductor layer (31) and the second semiconductor layer (32) may further include a larger number of layers, such as a clad layer or a TSBR (Tensile strain barrier reducing) layer.
[0154] The light-emitting layer (36) may be disposed between the first semiconductor layer (31) and the second semiconductor layer (32). The light-emitting layer (36) may include a material having a single or multiple quantum well structure. If the light-emitting layer (36) includes a material having a multiple quantum well structure, it may have a structure in which a quantum layer and a well layer are alternately stacked in multiple layers. The light-emitting layer (36) may emit light by the coupling of electron-hole pairs according to an electrical signal applied through the first semiconductor layer (31) and the second semiconductor layer (32). If the light-emitting layer (36) emits light in the blue wavelength range, it may include a material such as AlGaN or AlGaInN. In particular, if the light-emitting layer (36) has a structure in which a quantum layer and a well layer are alternately stacked in a multiple quantum well structure, the quantum layer may include a material such as AlGaN or AlGaInN, and the well layer may include a material such as GaN or AlInN. For example, as described above, the light-emitting layer (36) may include AlGaInN as the quantum layer and AlInN as the well layer, and the light-emitting layer (36) may emit blue light having a central wavelength band in the range of 450 nm to 495 nm.
[0155] However, it is not limited thereto, and the light-emitting layer (36) may have a structure in which semiconductor materials with a large band gap energy and semiconductor materials with a small band gap energy are alternately stacked, and may include different Group 3 to Group 5 semiconductor materials depending on the wavelength range of the emitted light. The light emitted by the light-emitting layer (36) is not limited to light in the blue wavelength range, and may emit light in the red or green wavelength range depending on the case. The length of the light-emitting layer (36) may have a range of 0.05㎛ to 0.10㎛, but is not limited thereto.
[0156] Meanwhile, light emitted from the light-emitting layer (36) can be emitted not only to the longitudinal outer surface of the light-emitting element (30) but also to both sides. The directionality of the light emitted from the light-emitting layer (36) is not limited to one direction.
[0157] The electrode layer (37) may be an ohmic connection electrode. However, it is not limited thereto and may be a Schottky connection electrode. The light-emitting element (30) may include at least one electrode layer (37). FIG. 5 illustrates the light-emitting element (30) including one electrode layer (37), but it is not limited thereto. Depending on the case, the light-emitting element (30) may include a larger number of electrode layers (37) or may omit them. The description of the light-emitting element (30) described below can be applied in the same way even if the number of electrode layers (37) changes or other structures are included.
[0158] The electrode layer (37) can reduce the resistance between the light-emitting element (30) and the electrode or connecting electrode when the light-emitting element (30) is electrically connected to the electrode or connecting electrode in a display device (10) according to one embodiment. The electrode layer (37) may include a conductive metal. For example, the electrode layer (37) may include at least one of aluminum (Al), titanium (Ti), indium (In), gold (Au), silver (Ag), ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), and ITZO (Indium Tin-Zinc Oxide). Additionally, the electrode layer (37) may include an n-type or p-type doped semiconductor material. The electrode layer (37) may include the same material or different materials, but is not limited thereto.
[0159] The insulating film (38) may be arranged to surround the outer surface of the plurality of semiconductor layers and electrode layers described above. For example, the insulating film (38) may be arranged to surround the outer surface of at least the light-emitting layer (36) and may extend in one direction in which the light-emitting element (30) extends. The insulating film (38) may perform the function of protecting the members. The insulating film (38) may be formed to surround the side portions of the members, but the two ends in the longitudinal direction of the light-emitting element (30) may be formed to be exposed.
[0160] In the drawing, the insulating film (38) is shown extending in the longitudinal direction of the light-emitting element (30) to cover from the first semiconductor layer (31) to the side of the electrode layer (37), but is not limited thereto. The insulating film (38) may cover only the outer surface of a portion of the semiconductor layer, including the light-emitting layer (36), or cover only a portion of the outer surface of the electrode layer (37), so that the outer surface of each electrode layer (37) is partially exposed. Additionally, the insulating film (38) may be formed with a rounded upper surface in cross-section in an area adjacent to at least one end of the light-emitting element (30).
[0161] The thickness of the insulating film (38) may be in the range of 10 nm to 1.0 µm, but is not limited thereto. Preferably, the thickness of the insulating film (38) may be around 40 nm.
[0162] The insulating film (38) may include materials having insulating properties, such as silicon oxide (SiOx), silicon nitride (SiNx), silicon oxynitride (SiOxNy), aluminum nitride (AlN), aluminum oxide (AlxOy), etc. The insulating film (38) may be formed as a single film or multiple films of materials having insulating properties. Accordingly, it is possible to prevent an electrical short circuit that may occur when the light-emitting layer (36) comes into direct contact with an electrode through which an electrical signal is transmitted to the light-emitting element (30). In addition, since the insulating film (38) protects the outer surface of the light-emitting element (30) including the light-emitting layer (36), it is possible to prevent a decrease in light-emitting efficiency.
[0163] Additionally, the outer surface of the insulating film (38) may be surface-treated. The light-emitting element (30) may be sprayed onto the electrode and aligned in a dispersed state within a predetermined ink. Here, in order for the light-emitting element (30) to remain dispersed without aggregating with other adjacent light-emitting elements (30) within the ink, the surface of the insulating film (38) may be treated to be hydrophobic or hydrophilic. For example, the outer surface of the insulating film (38) may be surface-treated with a material such as stearic acid, 2,3-naphthalene dicarboxylic acid, etc.
[0164] FIG. 6 is a plan view showing the arrangement of a color conversion member of a display device according to one embodiment. FIG. 7 is an enlarged view of area A of FIG. 2.
[0165] Referring to FIG. 6 in conjunction with FIG. 2, a display device (10) according to one embodiment may include a wavelength conversion layer (WLCL) including a color conversion member (CCL). The color conversion member (CCL) may be disposed in first to third light-emitting regions (LA1, LA2, LA3) on a second flattening layer (41). The color conversion member (CCL) may overlap with the first to third light-emitting regions (LA1, LA2, LA3) and may not overlap with the first to third light-blocking regions (BA1, BA2, BA3).
[0166] The color conversion member (CCL) can reduce the reflection of external light by absorbing external light incident from the outside through the first color filter (CF1) or the light transmission unit (LTU). To this end, the color conversion member (CCL) may be positioned overlapping the first color filter (CF1). For example, the color conversion member (CCL) may be positioned overlapping the first color filter (CF1) and the first wavelength conversion unit (WLC1) of the first light emission region (LA1). Additionally, the color conversion member (CCL) may be positioned overlapping the first color filter (CF1) and the second wavelength conversion unit (WLC2) of the second light emission region (LA2). Furthermore, the color conversion member (CCL) may be positioned overlapping the light transmission unit (LTU) of the third light emission region (LA3).
[0167] The color conversion member (CCL) may be positioned between the second flattening layer (41) and the first wavelength conversion unit (WLC1) in the first light-emitting region (LA1), between the second flattening layer (41) and the second wavelength conversion unit (WLC2) in the second light-emitting region (LA2), and between the second flattening layer (41) and the light transmission unit (LTU) in the third light-emitting region (LA3). That is, the color conversion member (CCL) may be positioned adjacent to the light-emitting element (30) of the light-emitting element layer (EML) than the first wavelength conversion unit (WLC1), the second wavelength conversion unit (WLC2), and the light transmission unit (LTU).
[0168] The color conversion member (CCL) can transmit light of a third color (e.g., blue light) and block light of other colors, e.g., red light and green light. For example, the color conversion member (CCL) can be made of a blue color filter. The color conversion member (CCL) can transmit light of the same color as the light emitted by the light-emitting element (30) of the light-emitting element layer (EML). For example, the light-emitting element (30) emits blue light, which is the third color light, and the color conversion member (CCL) can transmit the blue light, which is the third color light. Thus, it can transmit the blue light provided by the light-emitting element (30) and absorb external light incident from the outside to reduce the reflection of external light.
[0169] The color conversion member (CCL) can be placed within an area partitioned by the first light-blocking member (BK1). The color conversion member (CCL) is applied by inkjet printing within the first to third light-emitting areas (LA1, LA2, LA3) partitioned by the first light-blocking member (BK1), which has the advantage of eliminating the mask process.
[0170] The first wavelength conversion unit (WLC1), the second wavelength conversion unit (WLC2), and the light transmission unit (LTU) can be applied by inkjet printing after the formation of the color conversion member (CCL). When the color conversion member (CCL) is formed first by inkjet printing, the surface of the color conversion member (CCL) may have a wetting characteristic. Accordingly, the processability of the first wavelength conversion unit (WLC1), the second wavelength conversion unit (WLC2), and the light transmission unit (LTU) formed by inkjet printing on the color conversion member (CCL) can be improved.
[0171] Referring to FIG. 7 in conjunction with FIG. 2, in one embodiment, a color conversion member (CCL) may be disposed on a second flattening layer (41). The color conversion member (CCL) and its lower surface may be disposed in contact with the upper surface of the second flattening layer (41). The color conversion member (CCL) and the second flattening layer (41) may each have a predetermined refractive index. In one embodiment, the refractive index (n1) of the color conversion member (CCL) may be greater than the refractive index (n2) of the second flattening layer (41).
[0172] Blue light provided from the light-emitting element layer (EML) can pass through the encapsulation layer (TFE), pass through the second planarization layer (41), and be incident on the color conversion member (CCL). Since the color conversion member (CCL) and the second planarization layer (41) have different refractive indices, changes in the propagation path of the blue light, such as refraction, reflection, and transmission, occur at the interface between the color conversion member (CCL) and the second planarization layer (41). In one embodiment, the refractive index (n1) of the color conversion member (CCL) may be greater than the refractive index (n2) of the second planarization layer (41). Among the blue light that has passed through the second planarization layer (41), light incident perpendicularly to the interface between the color conversion member (CCL) and the second planarization layer (41) can pass through the color conversion member (CCL) without a change in path. Because the refractive index of the color conversion member (CCL) is large, it can be refracted toward the color conversion member (CCL). And among the blue light that has passed through the second flattening layer (41), the light incident obliquely on the interface between the color conversion member (CCL) and the second flattening layer (41) can be refracted and concentrated in the direction of the color conversion member (CCL) with a higher refractive index. As a result, the refractive index (n1) of the color conversion member (CCL) is made greater than the refractive index (n2) of the second flattening layer (41), thereby improving the light emission efficiency of the blue light emitted from the light-emitting element layer (EML).
[0173] FIGS. 8 to 10 are plan views showing various shapes of a reflective layer and a second light-blocking member according to one embodiment.
[0174] Referring to FIG. 8 to FIG. 10 in conjunction with FIG. 2, as described above, a reflective layer (RFL) and a second light-blocking member (BK2) may be disposed on the first capping layer (CAP1) in the first to third light-emitting regions (LA1, LA2, LA3) and the first to third light-blocking regions (BA1, BA2, BA3). The reflective layer (RFL) may include a plurality of first holes (HO1) that overlap with the first to third light-emitting regions (LA1, LA2, LA3). The second light-blocking member (BK2) may include a plurality of second holes (HO2) that overlap with the first to third light-emitting regions (LA1, LA2, LA3), in the same manner as the reflective layer (RFL). The reflective layer (RFL) and the second light-blocking member (BK2) can be formed into the same planar shape by overlapping each other, and the first hole (HO1) and the second hole (HO2) can also be formed into the same planar pattern shape by overlapping each other. Light emitted from the light-emitting element layer (EML) can be emitted to the outside through the first hole (HO1) and the second hole (HO2).
[0175] In an exemplary embodiment, the reflective layer (RFL) and the second light-blocking member (BK2) may be arranged in a stripe shape in the first to third light-emitting regions (LA1, LA2, LA3). As shown in FIG. 8, the reflective layer (RFL) and the second light-blocking member (BK2) in the first to third light-emitting regions (LA1, LA2, LA3) may be arranged in a stripe shape that extends in the second direction (DR2) and is spaced apart from each other in the first direction (DR1). The first hole (HO1) and the second hole (HO2) may also be arranged in a stripe shape that extends in the second direction (DR2) and is spaced apart from each other in the first direction (DR1).
[0176] As illustrated in FIG. 9, in another exemplary embodiment, the reflective layer (RFL) and the second light-blocking member (BK2) in the first to third light-emitting regions (LA1, LA2, LA3) may be arranged in a stripe shape that extends in the first direction (DR1) and is spaced apart from each other in the second direction (DR2). The first hole (HO1) and the second hole (HO2) may also be arranged in a stripe shape that extends in the first direction (DR1) and is spaced apart from each other in the second direction (DR2).
[0177] As illustrated in FIG. 10, in another exemplary embodiment, the reflective layer (RFL) and the second light-blocking member (BK2) in the first to third light-emitting regions (LA1, LA2, LA3) may be formed in a mesh shape. The first hole (HO1) and the second hole (HO2) may be arranged in a plurality of dot shapes of a square on a planar surface between the mesh-shaped reflective layer (RFL) and the second light-blocking member (BK2). However, this is not limited thereto, and the first hole (HO1) and the second hole (HO2) may be arranged in a plurality of dot shapes of a polygon other than a circular or square on a planar surface.
[0178] As described above, a display device (10) according to one embodiment can reduce the reflection of external light and improve the light emission efficiency of blue light provided by the light-emitting element layer (EML) by including a color conversion member (CCL) between wavelength conversion layers (WLCL).
[0179] FIG. 11 is a cross-sectional view showing a display device according to another embodiment. FIG. 12 is a plan view showing a color conversion member of a display device according to another embodiment.
[0180] Referring to FIGS. 11 and 12, a display device (10) according to one embodiment may include a color conversion member (CCL). The embodiment of FIGS. 11 and 12 differs from the embodiment of FIGS. 2 to 7 in that the arrangement of the color conversion member (CCL) is different. Hereinafter, the description of the identical configuration will be brief, and the differences will be described in detail.
[0181] A display device (10) according to one embodiment may include a wavelength conversion layer (WLCL) comprising a color conversion member (CCL). The color conversion member (CCL) may be disposed entirely on the second flattening layer (41). For example, the color conversion member (CCL) may be disposed in the first to third light-emitting regions (LA1, LA2, LA3) and the first to third light-blocking regions (BA1, BA2, BA3) and overlap with them. The color conversion member (CCL) may be disposed on the second flattening layer (41) in overlap with the first light-blocking member (BK1), the first wavelength conversion unit (WLC1), the second wavelength conversion unit (WLC2), and the light-transmitting unit (LTU).
[0182] Since the color conversion member (CCL) is placed entirely on the flat second flattening layer (41), the thickness of the color conversion member (CCL) can be made constant. For example, the thickness of the color conversion member (CCL) can be made the same in the first light-emitting region (LA1), the second light-emitting region (LA2), and the third light-emitting region (LA3), respectively.
[0183] Additionally, the color conversion member (CCL) can be formed by a solution process by being placed entirely on the second planarization layer (41). For example, the color conversion member (CCL) can be formed by various solution processes such as spin coating, slit coating, and inkjet printing. Accordingly, the color conversion member (CCL) can eliminate the mask process, thereby reducing manufacturing costs.
[0184] FIG. 13 is a cross-sectional view showing a display device according to another embodiment.
[0185] Referring to FIG. 13, a display device (10) according to one embodiment may include a wavelength conversion layer (WLCL) including a color conversion member (CCL). In one embodiment, the second flattening layer (41) is omitted, which differs from the embodiments of FIG. 2 to 7, FIG. 11, and FIG. 12 described above. Hereinafter, the description of the same configuration will be brief, and the differences will be described in detail.
[0186] A display device (10) according to one embodiment may include a wavelength conversion layer (WLCL) comprising a color conversion member (CCL). The color conversion member (CCL) may be disposed over the entire surface of the encapsulation layer (TFE). Since the color conversion member (CCL) is formed by a solution process and has flatness, the second flattening layer can be omitted, and it can absorb external light as well as function as the second flattening layer.
[0187] The color conversion member (CCL) may be placed in the first to third light-emitting regions (LA1, LA2, LA3) and the first to third light-blocking regions (BA1, BA2, BA3) and overlap with them. The color conversion member (CCL) may be placed on the second flattening layer (41) in overlap with the first light-blocking member (BK1), the first wavelength conversion unit (WLC1), the second wavelength conversion unit (WLC2), and the light-transmitting unit (LTU).
[0188] The color conversion member (CCL) may be in contact with the upper surface of the encapsulation layer (TFE) and the lower surface of the first light-blocking member (BK1), the first wavelength conversion part (WLC1), the second wavelength conversion part (WLC2), and the light-transmitting part (LTU), respectively. Since the color conversion member (CCL) is placed entirely on the encapsulation layer (TFE) and formed by a solution process, the mask process can be omitted, thereby reducing manufacturing costs. Additionally, the color conversion member (CCL) can omit the second planarization layer, thereby simplifying the process.
[0189] Although embodiments of the present invention have been described above with reference to the attached drawings, those skilled in the art will understand that the present invention may be implemented in other specific forms without changing the technical concept or essential features thereof. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive. Explanation of the symbols
[0190] 10: Display device 30: Light-emitting element 41: Second leveling layer 43: Third leveling layer TFTL: Circuit layer EML: Light-emitting diode layer TFE: Encapsulation layer CCL: Color change component WLCL: Wavelength conversion layer WLC1: First wavelength conversion unit WLC2: Second wavelength converter LTU: Light transmission unit BK1: First light-blocking member BK2: Second light-blocking member RFL: Reflective layer CFL: Color filter layer CF1: First color filter CAP1: First capping layer
Claims
Claim 1 A substrate comprising a first light-emitting region, a second light-emitting region, and a third light-emitting region, and a light-blocking region partitioning them; a plurality of light-emitting elements disposed on the substrate and respectively disposed in the first light-emitting region, the second light-emitting region, and the third light-emitting region; a planarization layer disposed on the plurality of light-emitting elements; and a wavelength conversion layer disposed on the planarization layer and comprising wavelength conversion parts, a light-transmitting part, and a color conversion member. and comprises a color filter layer disposed on the wavelength conversion layer and including a color filter, wherein the wavelength conversion units are respectively disposed in the first light-emitting region and the second light-emitting region, the light-transmitting unit is disposed in the third light-emitting region, the color conversion member is non-overlapping with the light-blocking region, and is disposed between the flattening layer and the wavelength conversion unit and between the flattening layer and the light-transmitting unit, wherein the wavelength conversion layer includes a first light-blocking member disposed on the flattening layer, and the color filter layer includes a reflection layer and a second light-blocking member disposed on the wavelength conversion layer, wherein the reflection layer and the second light-blocking member overlap with the first light-emitting region, the second light-emitting region, the third light-emitting region, and the light-blocking region, wherein the reflection layer includes a plurality of first holes that overlap with the first light-emitting region, the second light-emitting region, and the third light-emitting region, and the second light-blocking member includes a plurality of second holes that overlap with the first light-emitting region, the second light-emitting region, and the third light-emitting region, and the plurality of first holes and The above plurality of second holes are a display device that overlaps each other. Claim 2 In claim 1, the color conversion member is a display device positioned adjacent to the light-emitting element than the wavelength conversion members and the light transmission member. Claim 3 In claim 1, the color conversion member is a display device that transmits a color identical to the color of light emitted from the plurality of light-emitting elements. Claim 4 In claim 3, the color conversion member is a display device that is a color filter transmitting blue light. Claim 5 A display device according to claim 1, wherein the refractive index of the color conversion member is greater than the refractive index of the flattening layer. Claim 6 A display device according to claim 1, wherein the first light-blocking member overlaps with the light-blocking area and does not overlap with the first light-emitting area, the second light-emitting area, and the third light-emitting area. Claim 7 In claim 6, the color conversion member, the wavelength conversion member, and the light transmission member are disposed between the first light-blocking member. Claim 8 delete Claim 9 delete Claim 10 A display device according to claim 1, wherein the planar shape of the plurality of first holes and the plurality of second holes is a stripe shape or a dot shape. Claim 11 A display device according to claim 1, wherein the color filter is disposed in the first light-emitting region and the second light-emitting region, respectively, and does not overlap with the third light-emitting region. Claim 12 In claim 11, the color filter is a color filter that blocks blue light, and the display device. Claim 13 A display device according to claim 1, further comprising: a first electrode and a second electrode disposed on the substrate and extending in one direction; the light-emitting element aligned on the first electrode and the second electrode; and a first connecting electrode connected to one end of the light-emitting element and a second connecting electrode connected to the other end of the light-emitting element. Claim 14 In claim 13, the light-emitting element comprises a first semiconductor layer, a second semiconductor layer disposed on the first semiconductor layer, and a light-emitting layer disposed between the first semiconductor layer and the second semiconductor layer, and a display device comprising an insulating film surrounding the first semiconductor layer, the second semiconductor layer, and the light-emitting layer. Claim 15 A substrate comprising a first light-emitting region, a second light-emitting region, and a third light-emitting region, and a light-blocking region partitioning them; a plurality of light-emitting elements disposed on the substrate and respectively disposed in the first light-emitting region, the second light-emitting region, and the third light-emitting region; an encapsulation layer disposed on the plurality of light-emitting elements; and a wavelength conversion layer disposed on the encapsulation layer and comprising wavelength conversion parts, a light-transmitting part, and a color conversion member. and comprises a color filter layer disposed on the wavelength conversion layer and including a color filter, wherein the color conversion member is disposed on the encapsulation layer, the wavelength conversion members are respectively disposed on the color conversion member in the first light-emitting region and the second light-emitting region, the light-transmitting member is disposed on the color conversion member in the third light-emitting region, and the color conversion member overlaps with the first light-emitting region, the second light-emitting region, the third light-emitting region, and the light-blocking region, wherein the wavelength conversion layer includes a first light-blocking member disposed on the encapsulation layer, and the color filter layer includes a reflective layer and a second light-blocking member disposed on the wavelength conversion layer, wherein the reflective layer and the second light-blocking member overlap with the first light-emitting region, the second light-emitting region, the third light-emitting region, and the light-blocking region, wherein the reflective layer includes a plurality of first holes that overlap with the first light-emitting region, the second light-emitting region, and the third light-emitting region, and the second light-blocking member overlaps with the first light-emitting region, the second light-emitting region, and the third light-emitting region. A display device comprising a plurality of second holes, wherein the plurality of first holes and the plurality of second holes overlap each other. Claim 16 In claim 15, the color conversion member is in contact with the upper surface of the encapsulation layer and is in contact with the lower surface of the first light-blocking member, the wavelength conversion members, and the light-transmitting member. Claim 17 A display device according to claim 15, further comprising a flattening layer disposed between the encapsulation layer and the color conversion member, wherein the lower surface of the color conversion member contacts the upper surface of the flattening layer. Claim 18 In claim 17, the thickness of the color conversion member is the same in the first light-emitting region, the second light-emitting region, and the third light-emitting region of the display device. Claim 19 In claim 18, a display device in which the refractive index of the color conversion member is greater than the refractive index of the flattening layer. Claim 20 In claim 18, the color conversion member is a display device that transmits light of the same color as the light emitted from the plurality of light-emitting elements.
Citation Information
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