Display apparatus

Abstract

A display device according to the present invention comprises a substrate including a first region and a second region, a display element disposed in the first region for displaying an image, and a lens disposed above the display element in the first region, wherein the center of the display element and the center of the lens are separated by a certain distance.

Description

Technology Field

[0001] The present invention relates to a display device capable of improving brightness according to the viewing angle. Background Technology

[0003] Fat Pane Displays (FPDs) are widely used not only in desktop computer monitors but also in portable computers such as laptops and PDAs, as well as mobile phone terminals, due to their advantages in miniaturization and lightweight design. Examples of such flat-pane displays include liquid crystal displays, organic light-emitting diode displays, and quantum dot displays.

[0004] Flat panel displays are commonly used in TVs and computer monitors, but recently, they are also widely used in portable displays and user interfaces for other electronic devices. In particular, with the advancement of IT technology, they are being frequently adopted as instrument panels in automobiles.

[0005] Conventional instrument panels displayed various information about the vehicle, such as speed, fuel, and RPM, through analog display screens, but recently, flat panel displays are installed in the vehicle to display various information about the vehicle.

[0006] However, unlike computers or portable terminals, the user's viewing direction of a vehicle's instrument panel is fixed from horizontal to upward, and conventional display devices had a problem where brightness decreased in the upward direction. The problem to be solved

[0008] The present invention aims to provide a display device capable of improving brightness in a viewing direction that is not the front, such as in a vehicle instrument panel. means of solving the problem

[0010] To achieve the above objective, the display device according to the present invention comprises a substrate including a first region and a second region, a display element disposed in the first region to display an image, and a lens disposed above the display element in the first region, wherein the center of the display element and the center of the lens are spaced apart by a certain distance.

[0011] A light-blocking layer is formed in the second region, and a protective layer may be formed on the lens and the light-blocking layer.

[0013] The lens is a convex lens and can be composed of polymer resins such as acrylic resin, polyimide, polyamide, polycarbonate, polystyrene, and polyethylene terephthalate.

[0014] The separation distance between the center of the display element and the center of the lens can be determined by the emission angle of light from the center of the lens to the desired area, the magnification of the lens, the gap between the display element and the lens, and the angle of incidence of light emitted from the center of the display element and incident on the center of the lens.

[0015] The display element is formed with an asymmetric shape in which the light-emitting area varies depending on the region, and may be formed in a trapezoidal shape. In this case, the trapezoidal shape includes a first side, a second side longer than the first side, and a third side between the first and second sides, and the second side is determined by the lengths of the first and third sides of the trapezoid, the distance between the display element and the lens, the magnification of the lens, and the angle of incidence of light emitted from the center of the display element and incident on the center of the lens. Effects of the invention

[0017] In the present invention, the center of the light-emitting element and the center of the lens are not aligned but are spaced apart by a certain distance in the viewing direction, thereby enabling the improvement of brightness in a viewing direction at a certain angle rather than the front.

[0018] In addition, the present invention allows the area of ​​the light-emitting element to be varied according to the viewing direction, thereby increasing the amount of light supplied to a specific viewing direction and further improving the brightness in a specific viewing direction.

[0019] In addition, since the present invention enables high-efficiency driving by improving brightness according to the viewing direction, it is possible to realize a low-power display device with reduced power consumption. Brief explanation of the drawing

[0021] FIG. 1 is a drawing showing an instrument panel of a vehicle according to the present invention. FIG. 2 is a schematic block diagram of a display device according to the present invention. Figure 3 is a schematic block diagram of the subpixel shown in Figure 2. FIG. 4 is a circuit diagram conceptually showing a subpixel of an organic electroluminescent display device according to the present invention. FIG. 5 is a cross-sectional view specifically showing the structure of a display device according to the present invention. FIG. 6 is a plan view showing the arrangement relationship between a light-emitting element and a lens of a display device according to the present invention. Figure 7 is a diagram showing light emitted from a light-emitting element passing through a lens and being output to a user. Figure 8a is a diagram showing the optical profile of a conventional display device. FIG. 8b is a drawing showing the optical profile of a display device according to the present invention when the center of the light-emitting element and the center of the lens are separated by a certain distance and the light-emitting element is rectangular. FIG. 8c is a drawing showing the optical profile of a display device according to the present invention. FIG. 9 is a drawing showing the brightness according to the left-right viewing angle at an up-down viewing angle of +20 degrees for a display device according to the present invention and a conventional display device. FIG. 10 is a drawing showing a side view and a front view of a display device according to the present invention. Specific details for implementing the invention

[0022] 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.

[0023] Shapes, sizes, ratios, angles, numbers, etc. disclosed in the drawings for explaining embodiments of the present invention are exemplary and are not limited to the depicted details. Throughout the invention, the same reference numerals refer to the same components. Furthermore, in describing the present invention, if it is determined that a detailed description of related prior art may unnecessarily obscure the essence of the invention, such detailed description is omitted. Where terms such as "includes," "has," or "is made up" are used in the present invention, other parts may be added unless "only" is used. When a component is expressed in the singular, it includes cases where it is included in the plural unless specifically stated otherwise.

[0024] In interpreting the components, they are interpreted to include a margin of error even in the absence of a separate explicit statement.

[0025] In the case of describing a positional relationship, for example, when the positional relationship between two parts is described using expressions such as 'on,' 'upper,' 'lower,' or 'next to,' one or more other parts may be located between the two parts unless 'immediately' or 'directly' is used.

[0026] In the case of an explanation of a temporal relationship, for example, when a temporal sequence is explained using 'after', 'following', 'next', 'before', etc., it may include cases where the sequence is not continuous unless 'immediately' or 'directly' is used.

[0027] Although terms such as "first," "second," etc., are used to describe various components, these components are not limited by these terms. These terms are used merely to distinguish one component from another. Accordingly, the first component mentioned below may be the second component within the technical scope of the present invention.

[0028] In describing the components of the present invention, terms such as first, second, A, B, (a), (b), etc., may be used. These terms are intended only to distinguish the components from other components, and the nature, order, sequence, or number of the components are not limited by these terms. Where it is stated that a component is "connected," "combined," or "connected" to another component, it should be understood that the component may be directly connected or connected to the other component, but that other components may be "interposed" between each component, or that each component may be "connected," "combined," or "connected" through other components.

[0029] In the present invention, the term "display device" may include a display device in the narrow sense, such as a display module comprising a display panel and a driving unit for driving the display panel. Additionally, it may include a set electronic device or set device or set apparatus, such as an equipment display including a complete product or final product including a display module, such as a notebook computer, television, computer monitor, automotive display, or other forms of a vehicle, or a mobile electronic device such as a smartphone or electronic pad.

[0030] Accordingly, the display device in the present invention may include the display device itself in the narrow sense, such as a display module, and even a set device which is an application product or end-consumer device including the display module.

[0031] The present invention will be described in detail below with reference to the attached drawings.

[0032] FIG. 1 is a drawing showing an instrument panel of a vehicle according to the present invention.

[0033] Initially, vehicle instrument panels displayed information limited to simple numerical values ​​such as speed and RPM, as well as warning lights. However, with the recent advancement of IT technology leading to the digitization of information and the emergence of new vehicles like smart cars, connected cars, and even autonomous vehicles, there is a growing need to display a wider range of vehicle information. For instance, modern instrument panels must display various vehicle functions and situations, such as distance to the vehicle ahead, pedestrian recognition, approach warnings, cruise control data, lane keeping assist, and autonomous driving capabilities.

[0034] Moreover, as the time spent in vehicles increases, cars are evolving from mere means of transportation into increasingly functional entertainment vehicles that offer a variety of sights and sounds. For instance, they provide entertainment options such as movies and music, as well as games, for passengers as well as the driver.

[0035] Furthermore, instrument panels designed to provide this diverse information are gradually evolving from analog panels using mechanical gauges and needles, to hybrid panels with small displays integrated into analog panels, and finally to digital clusters where the entire instrument panel is utilized as a digital display.

[0036] Since analog instrument panels consist of physical objects for all numbers, scales, and needles, it is difficult to modify or change them. In contrast, a major advantage of digital instrument panels is that the display can be varied according to the driver, vehicle conditions, or driving mode.

[0037] As shown in FIG. 1, the instrument panel according to the present invention is composed of a display device (1) and is formed on the dashboard and center fascia of a vehicle.

[0038] At this time, the display device (1) is composed of a cluster positioned in front of the driver to display and provide vehicle operation information such as vehicle speed and RPM, various warning lights, vehicle approach warning, cruise driving information, lane keeping assist function, and autonomous driving, a CID (Center Information Display) positioned in the center of the front of the vehicle to display vehicle information such as the temperature inside and outside the vehicle and navigation, and combined with a mobile and audio system, and a co-driver display that provides various services such as video, audio, and games to the vehicle passengers, thereby providing various information to all occupants in the vehicle.

[0039] In the drawing, the cluster, CID, and passenger seat display may be configured as a single display device (1), but the cluster, CID, and passenger seat display may be configured separately and mounted on the dashboard and center fascia, respectively.

[0040] In addition, the cluster and passenger display may be integrated into a single display unit, while the CID is configured separately and mounted on the center fascia. In this case, the display is provided by the display unit manufacturer, and the CID, which connects to vehicle information and external devices such as mobile devices or audio, is installed by the vehicle manufacturer, allowing for the production of various instrument panels that highlight the unique characteristics of the vehicle company.

[0041] Various display devices may be applied to the above display device (1). For example, a flat panel display device such as a liquid crystal display or an organic electroluminescent display device may be applied as the display device (1) of the present invention.

[0042] Meanwhile, since the display device (1) of the present invention is mounted on the dashboard and center fascia inside the vehicle, it can be formed in various shapes depending on the type of vehicle. For example, the display device (1) can be formed as a curved surface following the shape of the dashboard and center fascia. To meet this requirement, the display device (1) must be formed as a flexible display device or a curved display device.

[0043] In addition, the vehicle's display device (1) must not only provide simple information such as vehicle information or driving information, but also provide services including high-definition video such as movies or games to the passenger through the passenger seat display, so the implementation of high-definition video is required.

[0044] Furthermore, since the vehicle's display device (1) is powered by a battery provided in the vehicle, it is necessary to minimize power consumption and thus minimize the burden on the battery.

[0045] Considering these points, the display device (1) of the present invention is suitable as a self-emissive display device such as an organic electroluminescent display device. An organic electroluminescent display device is suitable as a vehicle instrument panel because it is easy to manufacture flexible and curved display devices and has the advantage of having good image quality compared to other flat display devices such as liquid crystal displays, and also has the advantage of consuming less power compared to liquid crystal displays.

[0046] FIG. 2 is a schematic block diagram of a display device (100) according to an embodiment of the present invention, and FIG. 3 is a schematic block diagram of a subpixel (SP) shown in FIG. 2.

[0047] As shown in FIG. 2, the display device (100) is configured to include an image processing unit (102), a timing control unit (104), a gate driving unit (106), a data driving unit (107), a power supply unit (108), and a display panel (109).

[0048] The image processing unit (102) outputs a driving signal for driving various devices along with image data supplied from the outside. For example, the driving signal output from the image processing unit (102) may include a data enable signal, a vertical synchronization signal, a horizontal synchronization signal, and a clock signal.

[0049] The timing control unit (104) receives image data and a driving signal, etc., from the image processing unit (102). Based on the driving signal input from the image processing unit (102), the timing control unit (104) generates and outputs a gate timing control signal (GDC) for controlling the operation timing of the gate driving unit (106) and a data timing control signal (DDC) for controlling the operation timing of the data driving unit (107).

[0050] The gate driver (106) outputs a scan signal to the display panel (109) in response to a gate timing control signal (GDC) supplied from the timing control unit (104). The gate driver (106) outputs the scan signal through a plurality of gate lines (GL1~GLm). At this time, the gate driver (106) may be formed in the form of an IC (Integrated Circuit), but is not limited thereto. The gate driver (106) includes various gate driving circuits, and the gate driving circuits may be formed directly on the substrate of the display panel (109). In this case, the gate driver (106) may be a GIP (Gate-In-Panel).

[0051] The data driving unit (107) outputs a data voltage to a display panel (109) in response to a data timing control signal (DDC) input from the timing control unit (104). The data driving unit (107) samples and latches a digital data signal (DATA) supplied from the timing control unit (104) and converts it into an analog data voltage based on gamma voltage. The data driving unit (107) outputs the data voltage through a plurality of data lines (DL1~DLn). At this time, the data driving unit (107) may be formed in the form of an IC (Integrated Circuit), but is not limited thereto.

[0052] The power supply unit (108) outputs a high potential voltage (VDD) and a low potential voltage (VSS), etc., and supplies them to the display panel (109). The high potential voltage (VDD) is supplied to the display panel (109) through the first power line (EVDD), and the low potential voltage (VSS) is supplied to the display panel (109) through the second power line (EVSS). At this time, the voltage output from the power supply unit (108) may be output to the gate driving unit (106) or the data driving unit (107) and used for driving them.

[0053] The above display panel (109) displays an image in response to the data voltage and scan signal supplied from the gate driving unit (106) and the data driving unit (107), and the power supplied from the power supply unit (108).

[0054] The above display panel (109) is composed of a plurality of subpixels (SP) to display an actual image. The subpixels (SP) include a red subpixel, a green subpixel, and a blue subpixel, or a white (W) subpixel, a red (R) subpixel, a green (G) subpixel, and a blue (B) subpixel. At this time, the W, R, G, and B subpixels (SP) may all be formed with the same area, but may also be formed with different areas.

[0055] As shown in FIG. 3, one subpixel (SP) can be connected to a gate line (GL1), a data line (DL1), a first power line (EVDD), and a second power line (EVSS). The number of transistors and capacitors, as well as the driving method of the subpixel (SP), are determined according to the configuration of the pixel circuit.

[0056] FIG. 4 is a circuit diagram conceptually showing a subpixel (SP) of an organic electroluminescent display device (100) according to the present invention.

[0057] As illustrated in FIG. 4, the organic electroluminescent display device according to the present invention includes gate wiring (GL), data wiring (DL), and power wiring (PL) that intersect to define pixels (P), and a switching thin-film transistor (Ts), a driving thin-film transistor (Td), a storage capacitor (Cst), and a light-emitting element (130) are arranged in the pixels (P).

[0058] The switching thin-film transistor (Ts) is connected to the gate wiring (GL) and data wiring (DL), the driving thin-film transistor (Td) and storage capacitor (Cst) are connected between the switching thin-film transistor (Ts) and the power wiring (PL), and the light-emitting element (130) is connected to the driving thin-film transistor (Td).

[0059] In an organic electroluminescent display device of this structure, when a switching thin-film transistor (Ts) is turned on according to a gate signal applied to a gate wire (GL), a data signal applied to a data wire (DL) is applied to the gate electrode of a driving thin-film transistor (Td) and one electrode of a storage capacitor (Cst) through the switching thin-film transistor (Ts).

[0060] The above driving thin-film transistor (Td) is turned on according to a data signal applied to the gate electrode, and as a result, a current proportional to the data signal flows from the power wiring (PL) through the driving thin-film transistor (Td) to the light-emitting element (130), and the light-emitting element (130) emits light with a brightness proportional to the current flowing through the driving thin-film transistor (Td).

[0061] At this time, the storage capacitor (Cst) is charged with a voltage proportional to the data signal, so that the voltage of the gate electrode of the driving thin-film transistor (Td) is maintained constant during one frame.

[0062] In the drawing, only two thin-film transistors (Td, Ts) and one capacitor (Cst) are provided, but this is not limited to three or more thin-film transistors and two or more capacitors may be provided.

[0063] FIG. 5 is a cross-sectional view specifically showing the structure of a display device (100) according to the present invention.

[0064] As illustrated in FIG. 5, the display device (100) of the present invention includes a plurality of subpixels (SP1, SP2), and each of the subpixels (SP1, SP2) includes a light-emitting region (EA) and a non-light-emitting region (NEA). The subpixels (SP1, SP2) may include a red (R) subpixel, a green (G) subpixel, and a blue (B) subpixel. Additionally, the subpixels (SP1, SP2) may further include a white (W) subpixel.

[0065] A buffer layer (142) is formed on the substrate (140). The substrate (140) may be composed of a hard material such as glass, or may be composed of a plastic material such as polyimide, polymethylmethacrylate, polyethylene terephthalate, polyethersulfone, or polycarbonate, but is not limited thereto.

[0066] For example, if the substrate (140) is made of polyimide, it may be composed of multiple polyimides, and an inorganic layer may be further disposed between the polyimides, but is not limited thereto.

[0067] The buffer layer (142) is formed over the entire substrate (140) and can perform functions such as improving the adhesion between the layers formed thereon and the substrate (140), and blocking various types of defects, such as alkaline components leaking from the substrate (140). In addition, the buffer layer (142) can delay the diffusion of moisture or oxygen that has penetrated into the substrate (140).

[0068] The buffer layer (142) may be composed of a single layer of SiNx or SiOx or a multilayer thereof. If the buffer layer (142) is composed of a multilayer, SiOx and SiNx may be formed alternately. The buffer layer (142) may be omitted based on the type and material of the substrate (140), the structure and type of the thin-film transistor, etc.

[0069] A thin-film transistor is formed on the buffer layer (142) of the non-emissive region (EA) of each subpixel (SP1, SP2). For convenience of explanation, only the driving thin-film transistor among the various thin-film transistors that can be placed in the subpixels (SP1, SP2) is illustrated, but other thin-film transistors such as switching thin-film transistors may also be included. Additionally, although the thin-film transistor is described in the drawing as having a top-gate structure, it is not limited to this structure and may be implemented with other structures such as a bottom-gate structure.

[0070] Each thin-film transistor includes a semiconductor pattern (112) disposed on a buffer layer (142), a gate insulating layer (144) formed on the semiconductor pattern (112), a gate electrode (113) disposed on the gate insulating layer (144), an interlayer insulating layer (146) formed on the gate electrode (113), a source electrode (114) and a drain electrode (115) disposed on the interlayer insulating layer (146).

[0071] The semiconductor pattern (112) may be made of a polycrystalline semiconductor. For example, the polycrystalline semiconductor may be made of low-temperature polysilicon (LTPS) with high mobility, but is not limited thereto.

[0072] Additionally, the semiconductor pattern (112) may be made of an oxide semiconductor. For example, it may be made of any one of IGZO (Indium-gallium-zinc-oxide), IZO (Indium-zinc-oxide), IGTO (Indium-gallium-tin-oxide), and IGO (Indium-gallium-oxide), but is not limited thereto. The semiconductor pattern (112) is composed of a channel region (112a) in the central region and a source region (112b) and a drain region (112c), which are doping layers on both sides.

[0073] The gate insulating layer (144) may be formed in the display area (AA) and the non-display area (NA), or may be formed only in the display area (AA). The gate insulating layer (144) may be composed of a single layer or multiple layers made of inorganic materials such as SiOx or SiNx, but is not limited thereto.

[0074] The gate electrode (113) is made of metal. For example, the gate electrode (113) may be composed of a single layer or multiple layers made 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, but is not limited thereto.

[0075] The interlayer insulating layer (146) may be formed in the display area (AA) and the non-display area (NA), or may be formed only in the display area (AA). The interlayer insulating layer (146) may be composed of a single layer or multiple layers thereof, made of an organic material such as photoacrylic or an inorganic material such as SiNx or SiOx. Additionally, the interlayer insulating layer (146) may be composed of multiple layers of an organic layer and an inorganic layer, but is not limited thereto.

[0076] The source electrode (114) and the drain electrode (115) may be composed of a single layer or multiple layers made of any one of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu), or alloys thereof, but are not limited thereto. The source electrode (114) and the drain electrode (115) may each be contacted with the source region (112b) and the drain region (112c) of the semiconductor pattern (112) through contact holes formed in the gate insulating layer (144) and the interlayer insulating layer (146).

[0077] Although not shown in the drawing, a bottom shield metal layer may be disposed on the substrate (140) below the semiconductor pattern (112). The bottom shield metal layer is intended to prevent afterimages or degradation of transistor performance by minimizing back channel phenomena caused by charges trapped in the substrate (140), and may be composed of a single layer or multiple layers made of titanium (Ti), molybdenum (Mo), or an alloy thereof, but is not limited thereto.

[0078] A planarization layer (148) is formed on a substrate (140) on which a thin-film transistor is placed. The planarization layer (148) may be formed from an organic material such as photoacrylic, but is not limited thereto and may be composed of multiple layers consisting of an inorganic layer and an organic layer.

[0079] A light-emitting element (130) is disposed in the light-emitting region (EA) of the subpixel (SP1, SP2) on the flattening layer (148). Each light-emitting element (130) is composed of a first electrode (132), an organic layer (134), and a second electrode (136).

[0080] The first electrode (132) is placed on the flattening layer (148) and is electrically connected to the drain electrode (115) of the thin-film transistor through a contact hole formed in the flattening layer (148). The first electrode (132) may be formed from at least one of silver (Ag), aluminum (Al), gold (Au), molybdenum (Mo), tungsten (W), chromium (Cr), or an alloy thereof. The first electrode (132) is electrically connected to the drain electrode (115) of the thin-film transistor so that an image signal is applied from the outside.

[0081] Additionally, the first electrode (132) may be formed from a transparent metal oxide layer such as ITO (Indium Tin Oxide) or IZO (Indium Zinc Oxide). At this time, the first electrode (132) may further include an opaque conductive material to function as a reflective electrode that reflects light.

[0082] A bank layer (152) is formed at the boundary of the R, G, and B subpixels on the flattening layer (148). The bank layer (152) may be a type of barrier defining the R, G, and B subpixels.

[0083] The bank layer (152) may be made of at least one material among an inorganic insulating material such as SiNx or SiOx, an organic insulating material such as BCB (BenzoCycloButene), an acrylic resin, an epoxy resin, a phenolic resin, a polyamide resin, or a polyimide resin, or a photosensitive material including a black (or black) pigment, but is not limited thereto.

[0084] The organic layer (134) is formed on the upper surface of the first electrode (132), that is, on the inclined surface of the bank layer (152) of the light-emitting region (EA) or in a part of the upper surface of the bank layer (152). The organic layer (134) may include an R-light-emitting layer that emits red light, a G-light-emitting layer that emits green light, and a B-light-emitting layer that emits blue light, formed in R, G, and B pixels. Additionally, the organic layer (134) may include a W-light-emitting layer that emits white light. For example, the organic layer (134) may include an organic light-emitting layer or an inorganic light-emitting layer, for example, a nano-sized material layer, a quantum dot, a micro LED light-emitting layer, or a mini LED light-emitting layer, but is not limited thereto.

[0085] In the organic layer (134), in addition to the light-emitting layer, an electron injection layer and a hole injection layer that respectively inject electrons and holes into the light-emitting layer, and an electron transport layer, a hole blocking layer, an electron blocking layer, and a hole transport layer that respectively transport the injected electrons and holes to the light-emitting layer may be formed, but are not limited thereto.

[0086] The second electrode (136) is placed on the organic layer (134) and may be placed using a translucent conductive material that transmits light. For example, the second electrode (136) may be formed from at least one of alloys such as LiF / Al, CsF / Al, Mg:Ag, Ca / Ag, Ca:Ag, LiF / Mg:Ag, LiF / Ca / Ag, and LiF / Ca:Ag. Additionally, the second electrode (136) may be composed of a transparent metal oxide such as Indium Tin Oxide (ITO) or Indium Zinc Oxide (IZO), but is not limited thereto. It may be formed across a plurality of subpixels (SP1, SP2) of the second electrode (136).

[0087] Additionally, the light-emitting element (130) may be configured in a tandem structure. The tandem structure includes a plurality of organic light-emitting layers, and a charge-generating layer may be included between the organic light-emitting layers. The charge-generating layer is intended to regulate the charge balance between the plurality of organic light-emitting layers and may be composed of a plurality of layers including a first charge-generating layer and a second charge-generating layer. The charge-generating layer may include an N-type charge-generating layer and a P-type charge-generating layer, and may be composed of an organic layer doped with an alkali metal such as Li, Na, K, Cs, or an alkaline earth metal such as Mg, Sr, Ba, or Ra, but is not limited thereto.

[0088] An encapsulation layer (160) is formed on the light-emitting element (130). If the light-emitting element (130) is exposed to impurities such as moisture or oxygen, a pixel shrinkage phenomenon in which the light-emitting area is reduced may occur, or defects such as dark spots within the light-emitting area may occur. In addition, moisture or oxygen oxidizes electrodes made of metal. The encapsulation layer (160) prevents defects in the light-emitting element (130) and various electrodes by blocking the penetration of impurities such as oxygen and moisture from the outside.

[0089] The bag layer (160) may be composed of a first bag layer (162), a second bag layer (164), and a third bag layer (166), but is not limited thereto; it may be formed as a two-layer structure of an organic film and an inorganic film, or as a structure of four or more layers.

[0090] The first sealing layer (162) and the third sealing layer (166) may be composed of inorganic materials such as SiOx or SiNx, but are not limited thereto.

[0091] The second sealing layer (164) may be composed of an organic insulating material such as acrylic resin, epoxy resin, polyimide, polyethylene, or silicon oxycarbon (SiOC), but is not limited thereto.

[0092] A lens (170) is placed in the light-emitting region (EA) above the encapsulation layer (160), and a light-blocking layer (172) is formed between the lens (170) of the non-light-emitting region (NEA), and a protective layer (174) can be formed on the lens (170) and the light-blocking layer (172).

[0093] In the drawing, the lens (170) is placed on the encapsulation layer (160), but if the display device (100) is a bottom-emitting display device (100), the lens (170) may be placed below the light-emitting element (130) and may also be formed on the lower surface of the substrate (140).

[0094] Lenses (170) are formed for each light-emitting region (EA) of subpixels (SP1, SP2) and are spaced apart from each other by a set distance (e.g., the distance of a non-light-emitting region (NEA)). Lenses (170) may be convex lenses that are convex along the upward direction in which light is output. If the display device (100) is a bottom-emitting display device (100), the lenses (170) may be convex lenses that are convex in the downward direction.

[0095] A lens (170) placed in each of the plurality of light-emitting regions (EA) refracts and outputs light emitted from the light-emitting element (130) of the corresponding subpixel (SP1, SP2). At this time, since the light passing through the lens (170) is refracted in the forward direction, the brightness of the display device (100) is improved by the lens (170).

[0096] The lens (170) may be composed of a polymer resin having light transmittance. For example, the lens (170) may be composed of at least one selected from among acrylic resin, polyimide, polyamide, polycarbonate, polystyrene, and polyethylene terephthalate, but is not limited thereto.

[0097] The light-blocking layer (172) absorbs light. Specifically, the light-blocking layer (172) blocks or absorbs light emitted from the first subpixel (SP1) that is output to the second subpixel (SP2), thereby preventing the color of the first subpixel (SP1) and the color of the second subpixel (SP2) from mixing. The light-blocking layer (172) may be composed of black resin and may be composed of a metallic material such as Cr or CrOx, but is not limited thereto.

[0098] The protective layer (174) may be composed of at least one layer made of organic or inorganic material, and may be composed of multiple layers of inorganic and organic layers, but is not limited thereto.

[0099] The lens (170) is formed by being aligned on the upper surface of the light-emitting element (130), or, strictly speaking, the organic layer (134) that emits actual light. In this case, in the present invention, the center (CL) of the lens (170) and the center (CE) of the light-emitting element (130) do not coincide and are spaced apart by a set distance (L).

[0100] In this way, separating the center (CL) of the lens (170) and the center (CE) of the light-emitting element (130) by a set distance (L) is intended to increase brightness in a specific viewing direction rather than in the front.

[0101] For example, when the display device (100) of the present invention is applied to the instrument panel of a vehicle, the display device (100) is positioned lower than the driver's field of vision, so the light input from the display device (100) to the driver's eye is output at a certain angle from the horizontal direction to the upward direction.

[0102] Generally, the maximum brightness of the display device (100) is in the direction of the frontal view, and the brightness decreases significantly as the view moves up and down or left and right. Therefore, when the display device (100) is applied to a vehicle, the light (image) input to the driver's eyes is light with significantly reduced brightness, so the driver's visibility when looking at the instrument panel is reduced.

[0103] In the present invention, to improve brightness in a viewing direction that is not the front but has a certain angle with respect to the front, the center (CE) of the light-emitting element (130) and the center (CL) of the lens (170) are not aligned but are spaced apart by a certain distance in the viewing direction to improve brightness in this viewing direction. In addition, in the present invention, the brightness in a specific viewing direction is further improved by varying the area of ​​the light-emitting element (130), specifically the area of ​​the region that emits light, according to the viewing direction. This is explained in detail below.

[0104] FIG. 6 is a plan view showing the arrangement relationship between the light-emitting element (130) and the lens (170) of the display device (100) according to the present invention.

[0105] As illustrated in FIG. 6, the light-emitting element (130) and the lens (170) are arranged overlapping each other within a subpixel. At this time, the center (CE) of the light-emitting element (130) and the center (CL) of the lens (170) do not coincide with each other and are spaced apart from each other. That is, the center (CE) of the light-emitting element (130) may be arranged at a distance (L) set in the -y direction from the center (CL) of the lens (170), or the center (CL) of the lens (170) may be arranged at a distance (L) set in the +y direction from the center (CE) of the light-emitting element (130).

[0106] FIG. 7 is a diagram showing light emitted from a light-emitting element (130) being output to a user through a lens (170). In the diagram, position a1 corresponds to the center (CE) of the light-emitting element (130), a2 is the position where light emitted from the center of the light-emitting element (130) is output through the lens (170), a3 is the position where light emitted from the lowest part of the light-emitting element (130) is output through the lens (170), and a4 is the position where light emitted from the uppermost part of the light-emitting element (130) is output through the lens (170).

[0107] As illustrated in FIG. 7, the center (CE) of the light-emitting element (130) is positioned at a distance (L) set in the -y direction from the center (CL) of the lens (170), that is, the center (CE) of the light-emitting element (130) is located below the center (CL) of the lens (170), so the light emission area emitted from the light-emitting element (130) moves upward relative to the center of the light-emitting element (130). Therefore, the light emission area with the highest brightness also moves upward relative to the center of the light-emitting element (130), so the brightness in the direction above the horizontal plane of the display device (100) increases.

[0108] Additionally, as shown in FIG. 6, the light-emitting element (130) is formed in a trapezoidal shape such that the width of the bottom of the plane is wider than the width of the top. Accordingly, in the light-emitting element (130), the amount of light emitted from the bottom is greater than the amount of light emitted from the top.

[0109] As illustrated in FIG. 7, light emitted from the top of the light-emitting element (130) passes through the lens (170) and is emitted toward the lower side (i.e., the -y direction side) of the center (CE) of the light-emitting element (130), and light emitted from the top of the light-emitting element (130) passes through the lens (170) and is emitted toward the upper side (i.e., the +y direction side) of the center (CE) of the light-emitting element (130). Since the amount of light emitted from the bottom of the trapezoidal light-emitting element (130) is greater than the amount of light emitted from the top, the amount of light output in the upward direction relative to the horizontal plane of the display device (100) is relatively greater, and thus the brightness in the upward direction relative to the horizontal plane of the display device (100) increases further.

[0110] In this way, the present invention is formed such that the center (CE) of the light-emitting element (130) and the center (CL) of the lens (170) are spaced apart by a certain distance, and the shape of the light-emitting element (130) is formed such that the area of ​​one side is larger (e.g., a trapezoidal shape), thereby improving the brightness in the upper viewing direction (+y viewing direction).

[0111] In addition, by forming the shape of the light-emitting element (130) into a trapezoid, the light-emitting area in the ±x direction from the bottom is increased. Accordingly, the brightness in the ±x direction in the direction above the horizontal plane of the display device (100) is increased compared to the brightness in the ±x direction in the direction above the horizontal plane.

[0112] FIG. 8a is a drawing showing the optical profile of a conventional display device in which the center (CE) of the light-emitting element (130) and the center (CL) of the lens (170) coincide and the light-emitting element (130) is rectangular; FIG. 8b is a drawing showing the optical profile when the center (CE) of the light-emitting element (130) and the center (CL) of the lens (170) are separated by a certain distance and the light-emitting element (130) is rectangular; and FIG. 8c is a drawing showing the optical profile of the present invention in which the center (CE) of the light-emitting element (130) and the center (CL) of the lens (170) are separated by a certain distance and the light-emitting element (130) is trapezoidal.

[0113] At this time, the two blue lines in the optical profile represent vertical viewing angles of 20 degrees and -10 degrees, respectively. When the display device (100) of the present invention is applied to the instrument panel of a vehicle, the angle between the center of the display device (100) and the driver's eyes is approximately 20 degrees, although this varies depending on the driver's height and the height of the driver's seat. Therefore, in the present invention, it is very important to improve the brightness at a vertical viewing angle of 20 degrees.

[0114] Comparing FIG. 8a and FIG. 8b, it can be seen that there is almost no difference in brightness at a viewing angle of -10 degrees, but at a viewing angle of +20 degrees, the brightness is greatly improved when the center (CE) of the light-emitting element (130) and the center (CL) of the lens (170) are separated by a certain distance (L) compared to when the center (CE) of the light-emitting element (130) and the center (CL) of the lens (170) coincide.

[0115] In addition, when comparing FIG. 8b and FIG. 8c, it can be seen that as the light-emitting element (130) is formed in a trapezoidal shape, the brightness in the left and right viewing directions is also improved at the upper outer part, that is, at a viewing angle of +20 degrees.

[0116] Accordingly, comparing FIG. 8a and FIG. 8c, compared to the case of a conventional display device in which the center (CE) of the light-emitting element (130) and the center (CL) of the lens (170) coincide and the light-emitting element (130) is rectangular, the brightness in the display device (100) according to the present invention is greatly increased at an upward viewing angle of +20 degrees, and the brightness in the left-right viewing angle is also greatly increased at an upward viewing angle of +20 degrees.

[0117] FIG. 9 is a diagram showing the brightness according to the left-right viewing angle at an up-down viewing angle of +20 degrees of a conventional display device in which the center (CE) of the light-emitting element (130) and the center (CL) of the lens (170) coincide with the center of the display device (100) and the light-emitting element (130) according to the present invention, and the light-emitting element (130) is rectangular. At this time, the x-axis is the left-right viewing angle direction and the y-axis is the brightness.

[0118] As shown in FIG. 9, while the brightness of a conventional display device is approximately 290 nits at a left-right viewing angle of 0 degrees, the brightness of the present invention is improved to approximately 370 nits at a left-right viewing angle of 0 degrees. In addition, the brightness of the display device of the present invention is significantly improved compared to the conventional display device at a left-right viewing angle of approximately ±38 degrees.

[0119] FIG. 10 is a drawing showing a side view and a front view of a display device (100) according to the present invention. With reference thereto, the distance (L) between the center (CE) of the light-emitting element (130) and the center (CL) of the lens (170) and the shape of the trapezoidal light-emitting element (130) will be described in detail.

[0120] In FIG. 10, θ1 is the angle of emission of light from the center (CL) of the lens (170) to a desired area (a2), for example, the area where the driver's eye is located in a vehicle, and θ2 is the angle of incidence of light entering from the center (CE) of the light-emitting element (130) to the center (CL) of the lens (170). At this time, D is the distance between the light-emitting element (130) and the lens (170).

[0121] The distance (D) between the light-emitting element (130) and the lens (170) can be derived as shown in the following mathematical formula 1.

[0122]

[0123]

[0124]

[0125]

[0126] In mathematical formula 1, M is the magnification of the lens, which is determined by the exit angle (θ1) of the desired area (a1) from the center (CL) of the lens (170) and the incident angle (θ2) of the light input from the center (CE) of the light-emitting element (130) to the center (CL) of the lens (170).

[0127] For example, if the distance (D) between the light-emitting element (130) and the lens (170) is 25.8 μm and the exit angle (θ1) of the desired area (a1) from the center (CL) of the lens (170) is 2 degrees (D=25.8 μm, θ1=2°), then θ1 / M is 1.3°, so L=25.8 μm × tan1.3°=0.6 μm. Therefore, by forming the light-emitting element (130) and the lens (170) within the display device (100) such that the distance (L) between the center (CE) of the light-emitting element (130) and the center (CL) of the lens (170) is 0.6 μm, the brightness of the desired upper viewing direction can be improved.

[0128] In addition, when the upper side length of the trapezoidal light-emitting element (130) is S, the lower side length is (S+2T), and the height is H, the length T extending from the upper side is given by the following mathematical formula 2.

[0129]

[0130] Here, A and B are the lengths of the light-emitting element (130) in the -y direction and +y direction, respectively, from the center of the lens (170), and can be obtained from Equation 1 (A=(H / 2)+1, B=(H / 2)-1, where H is the height of the trapezoidal light-emitting element (130).

[0131] When the length of the upper side (S) of the trapezoidal light-emitting element (130) is 20㎛ and the height (H) is 12㎛ (S=20㎛, H=12㎛), A and B are respectively A=(12 / 2)+0.6=6.6㎛ and B=(12 / 2)-0.6=5.4㎛, so T=20 / 2×(6.6 / 5.4 -1)=2.2㎛.

[0132] In this way, in the present invention, the distance (L) between the center (CE) of the light-emitting element (130) and the center (CL) of the lens (170) and the shape of the trapezoidal light-emitting element (130) are determined by factors such as the position of the user's eye, the magnification of the lens, the length and height of the upper side of the light-emitting element (130), and the distance between the light-emitting element (130) and the lens (170).

[0133] In the above description, the light-emitting element is formed with an asymmetric trapezoidal shape, but the light-emitting element in the present invention is not limited to a trapezoidal shape. Since the present invention improves brightness in the vertical viewing direction by forming the shape of the light-emitting element asymmetrically to make the light-emitting area of ​​a specific region larger than that of another region, the light-emitting element can be formed in various shapes as long as it is possible to form an asymmetric shape with different light-emitting areas.

[0134] In addition, although the above description used an organic electroluminescent display element as an example, the present invention is not limited to such specific display devices but can be applied to various display devices such as liquid crystal displays, quantum dot displays, miniLED displays, microLEDs, and display devices.

[0135] Furthermore, the display device of the present invention is not limited to application to vehicle instrument panels but can be used for various purposes. In particular, in the present invention, when the viewing direction is not directly forward but at a certain angle, the brightness in the viewing direction can be improved by separating the center of the light-emitting element and the lens by a certain distance according to the viewing direction and forming the shape of the light-emitting element asymmetrically.

[0136] Although embodiments of the present invention have been described in more detail with reference to the attached drawings, the present invention is not necessarily limited to these embodiments and can be modified in various ways within the scope of the technical spirit of the present invention. Accordingly, the embodiments disclosed in the present invention are intended to explain, not to limit, the technical spirit of the present invention, and the scope of the technical spirit of the present invention is not limited by these embodiments. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive. Explanation of the symbols

[0138] 140 : Substrate 112 : Semiconductor pattern 114: Source electrode 115: Drain electrode 132: First electrode 134: Organic layer 136 : Second electrode 142 : Buffer layer 144: Gate insulation layer 146: Interlayer insulation layer 160 : Encapsulation layer 170 : Lens 172 : Shading layer 174 : Protective layer

Claims

Claim 1 A display device comprising: a substrate including a first region and a second region; a display element disposed in the first region to display an image; and a lens disposed above the display element in the first region, wherein, with respect to the center of the display element, the light-emitting area of ​​the display element located in a first direction corresponding to the viewing direction is larger than the light-emitting area of ​​the display element located in a second direction corresponding to a direction symmetric to the viewing direction, and the lens moves along the second direction from the center of the display element so that the center of the display element and the center of the lens are separated by a certain distance. Claim 2 A display device according to claim 1, further comprising a light-blocking layer formed in the second region. Claim 3 A display device comprising, in paragraph 2, a protective layer disposed on the lens and the light-blocking layer. Claim 4 A display device according to claim 1, wherein the lens is a convex lens. Claim 5 In claim 1, the lens is a display device composed of a polymer resin. Claim 6 In claim 1, the lens is a display device composed of at least one material selected from the group consisting of acrylic resin, polyimide, polyamide, polycarbonate, polystyrene, and polyethylene terephthalate. Claim 7 A display device according to claim 1, wherein the separation distance between the center of the display element and the center of the lens is determined by the angle of emission of light from the center of the lens to a desired area, the magnification of the lens, the distance between the display element and the lens, and the angle of incidence of light emitted from the center of the display element and incident on the center of the lens. Claim 8 delete Claim 9 In claim 1, the display element is a display device having a trapezoidal shape. Claim 10 In claim 9, the trapezoidal shape comprises a first side, a second side longer than the first side, and a third side between the first side and the second side, wherein the second side is determined by the length of the first side and the third side of the trapezoid, the distance between the display element and the lens, the magnification of the lens, and the angle of incidence of light emitted from the center of the display element and incident on the center of the lens. Claim 11 A display device according to claim 1, further comprising a sealing layer disposed between the display element and the lens. Claim 12 In paragraph 11, the lens is a display device placed on the encapsulation layer. Claim 13 In claim 1, the display device comprises an organic electroluminescent display element, a liquid crystal display element, a quantum dot display element, a microLED display element, and a miniLED display element. Claim 14 A display device according to claim 1, wherein the distance between the center of the display element and the center of the lens is the same over the entire substrate, and the amount of light emitted from the display element is the same over the entire substrate.

Images