Light emitting module and display device including same

Abstract

A light emitting device according to the present invention comprises: a substrate; a cover layer disposed on the upper surface of the substrate and having at least one opening exposing at least a partial region of the upper surface of the substrate; a light emitting element disposed on the upper surface of the substrate exposed through the opening; and a molding layer covering the cover layer and the light emitting element.

Description

Light-emitting module and display device including the same

[0001] The present invention relates to a light-emitting module and a display device including the same, and more particularly, to a light-emitting module composed of a plurality of light-emitting diode chips and a display device including the same.

[0002] Light-emitting diodes (LEDs), semiconductor devices that utilize inorganic light sources, are widely used in various fields, including display devices, vehicle lamps, and general lighting. Light-emitting diodes (LEDs) are rapidly replacing existing light sources due to their long lifespan, low power consumption, and fast response times.

[0003] Meanwhile, conventional light-emitting diodes (LEDs) have primarily been used as backlight sources in display devices. Recently, display devices that directly display images using LEDs are being developed. These displays are also referred to as micro LED displays.

[0004] Display devices typically use a mixture of blue, green, and red to produce a variety of colors. To produce various images, display devices comprise multiple pixels, each of which has blue, green, and red sub-pixels. The colors of these sub-pixels determine the color of a specific pixel, and the combination of these pixels produces an image.

[0005] In micro LED displays, micro LEDs are arranged on a two-dimensional plane, corresponding to each subpixel, and thus, a large number of micro LEDs must be placed on a single substrate. However, micro LEDs are extremely small, typically less than 200 micrometers or even 100 micrometers, and this small size can lead to various problems.

[0006] In particular, in molding a large number of micro LEDs mounted on a substrate, the conventional molding method of applying a thermosetting resin on the substrate and curing it causes several problems, such as a decrease in luminous efficiency due to the influence of the molding layer and difficulty in increasing hardness.

[0007] The purpose of the present invention is to provide a light-emitting device having high luminous efficiency and capable of improving color clarity, and a display device including the same.

[0008] A light-emitting device according to one embodiment of the present invention includes a substrate, a cover layer formed on an upper surface of the substrate and forming at least one opening exposing at least a portion of an upper surface of the substrate, a light-emitting element formed on an upper surface of the substrate exposed through the opening, and a molding layer covering the cover layer and the light-emitting element.

[0009] In one embodiment of the present invention, the cover layer may be a coating layer containing a black pigment.

[0010] In one embodiment of the present invention, the light-emitting element may include a transparent substrate and a semiconductor layer that is disposed on one surface of the transparent substrate and generates light.

[0011] In one embodiment of the present invention, the thickness of the cover layer may be thicker than the thickness of the semiconductor layer.

[0012] In one embodiment of the present invention, the size of the opening on the plane may be smaller than the size of the light-emitting element.

[0013] In one embodiment of the present invention, the molding layer may include a first molding layer that exposes the upper surface of the light-emitting element and covers at least a portion of a side surface of the light-emitting element, and a second molding layer that covers the first molding layer and the upper surface of the light-emitting element.

[0014] In one embodiment of the present invention, the first molding layer may include at least one of a light reflective material and a light absorbing material.

[0015] In one embodiment of the present invention, the second molding layer may be a light-transmitting layer.

[0016] In one embodiment of the present invention, the upper surface of the first molding layer positioned between two adjacent light-emitting elements can form a concave surface.

[0017] In one embodiment of the present invention, the thickness from the upper surface of the substrate to the lowest point of the concave surface of the first molding layer may be thicker than the thickness from the lowest point of the concave surface to the upper surface of the second molding layer.

[0018] In one embodiment of the present invention, the thickness of the cover layer may be thicker than the thickness from the lowest point of the concave surface of the first molding layer to the highest point of the concave surface.

[0019] In one embodiment of the present invention, the longitudinal width of the light-emitting element may be longer than the thickness from the upper surface of the light-emitting element to the upper surface of the second molding layer.

[0020] In one embodiment of the present invention, three light-emitting elements emitting light of different peak wavelengths and arranged in a first direction on a plane can form one pixel.

[0021] In one embodiment of the present invention, the light emitting device may include a plurality of pixels arranged in a grid shape along the first direction and a second direction perpendicular to the first direction.

[0022] In one embodiment of the present invention, the maximum distance between two light-emitting elements at opposite ends within the pixel based on the first direction may be longer than the shortest distance between two neighboring pixels based on the second direction.

[0023] In one embodiment of the present invention, the distance between two neighboring light-emitting elements within the pixel with respect to the first direction may be smaller than the shortest distance between two neighboring pixels with respect to the first direction.

[0024] The present invention can provide a light-emitting device having high luminous efficiency and capable of improving color clarity, and a display device including the same.

[0025] Figure 1 is a plan view showing a display device of the present invention.

[0026] FIG. 2 is a drawing illustrating a light-emitting diode constituting the display device of FIG. 1.

[0027] FIGS. 3A and 3B are side views showing light-emitting elements arranged in a display device according to one embodiment of the present invention.

[0028] FIG. 4 is a side view showing light-emitting elements arranged in a display device according to another embodiment of the present invention.

[0029] FIGS. 5A and 5B are side and plan views showing a portion of a display device according to another embodiment of the present invention.

[0030] FIG. 6 is a side view showing a portion of a display device according to another embodiment of the present invention.

[0031] FIG. 7 is a side view showing a portion of a display device according to another embodiment of the present invention.

[0032] Figures 8a and 8b are graphs showing color differences according to position of a light-emitting device and a display device according to the present invention.

[0033] In the following description, for purposes of explanation, numerous specific details are set forth to provide a thorough understanding of various embodiments or implementations of the present disclosure. As used herein, the terms "embodiment" and "implementation" are interchangeable to refer to non-limiting examples of devices or methods that utilize one or more of the inventive concepts disclosed herein. However, it will be apparent that various embodiments may be practiced without utilizing these specific details or using one or more equivalent arrangements. In other instances, well-known structures and devices are shown in block diagram form to avoid unnecessarily obscuring the various embodiments. Furthermore, while the various embodiments may vary from one another, they are not necessarily exclusive. For example, specific features, configurations, and characteristics of an embodiment may be utilized or implemented in other embodiments without departing from the scope of the inventive concepts.

[0034] Unless otherwise specified, the illustrated embodiments should be understood to provide exemplary features of varying details of some ways in which the concepts of the present invention may be practically implemented. Therefore, unless otherwise specified, the features, components, modules, layers, membranes, panels, regions, and / or aspects (hereinafter, individually or collectively referred to as "elements") of the various embodiments may be differently combined, separated, interchanged, and / or rearranged without departing from the scope of the concepts of the present invention.

[0035] The use of cross-hatching and / or shading in the accompanying drawings is generally provided to clarify boundaries between adjacent elements. As such, the presence or absence of cross-hatching or shading, unless expressly stated, does not imply or indicate any preference or requirement for any particular material, material properties, dimensions, proportions, commonality between the illustrated elements, and / or any other features, properties, or characteristics of the elements. Furthermore, in the accompanying drawings, the dimensions and relative sizes of elements may be exaggerated for clarity and / or illustrative purposes. When embodiments are implemented differently, certain process sequences may be performed differently from the illustrated sequence. For example, two consecutively illustrated processes may be performed substantially simultaneously or in a reverse order from the illustrated sequence. Furthermore, like reference numerals designate like elements.

[0036] When an element, such as a layer, is referred to as being "on," "connected to," or "joined to" another element or layer, the element may be directly on, connected to, or joined to the other element or layer, or there may be intervening elements or layers present. However, when an element or layer is referred to as being "directly on," "directly connected to," or "directly joined to" another element or layer, there are no intervening elements or layers present. For this purpose, the term "connected" may refer to physical, electrical, and / or fluidic connections, with or without intervening elements. Furthermore, the DR1-axis, DR2-axis, and DR3-axis are not limited to the three axes of a Cartesian coordinate system, such as the x, y, and z-axes, and may be interpreted in a broader sense. For example, the DR1-axis, DR2-axis, and DR3-axis may be perpendicular to one another, or may represent different directions that are not perpendicular to one another. For purposes of this disclosure, “at least one of X, Y, and Z” and “at least one selected from the group consisting of X, Y, and Z” may be interpreted as only X, only Y, only Z, or any combination of two or more of X, Y, and Z, such as, for example, XYZ, XYY, YZ, and ZZ. The term “and / or” as used herein includes any and all combinations of one or more of the associated listed items.

[0037] Although the terms "first," "second," and the like may be used herein to describe various types of elements, these elements should not be limited by these terms. These terms are used to distinguish one element from another. Therefore, the first element discussed below may be referred to as the second element without departing from the teachings of the present disclosure.

[0038] Spatially relative terms such as "beneath," "beneath," "directly beneath," "lower," "above," "upper," "above," "higher than," "side" (as in, for example, a "side wall"), and the like may be used for descriptive purposes and thereby to describe the relationship of one element to other element(s) as depicted in the drawings. Spatially relative terms are intended to encompass different orientations of the device in use, operation, and / or manufacture in addition to the orientations depicted in the drawings. For example, if the device in the drawings were turned over, an element described as "beneath" or "beneath" another element or feature would then be oriented "above" the other element or feature. Therefore, the exemplary term "beneath" can encompass both orientations above and below. Furthermore, the device can be oriented differently (e.g., rotated 90° or oriented in other orientations), and thus the spatially relative descriptors used herein can also be interpreted accordingly.

[0039] The terminology used herein is for the purpose of describing particular embodiments and is not limiting. The singular forms "a," "an," and "the" as used herein also include the plural forms unless the context clearly dictates otherwise. Furthermore, the terms "comprises," "comprising," "includes," and / or "comprising" as used herein specify the presence of stated features, integers, steps, operations, elements, components, and / or groups thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. Furthermore, the terms "substantially," "about," and other similar terms as used herein are used as terms of approximation rather than degrees, and as such, are used to describe inherent deviations from measured, calculated, and / or provided values ​​that would be recognized by one of ordinary skill in the art.

[0040] Various embodiments are described below with reference to cross-sectional and / or exploded illustrations, which are schematic illustrations of idealized embodiments and / or intermediate structures. As such, variations from the shapes of the illustrated drawings may be expected, for example, as a result of manufacturing techniques and / or tolerances. Therefore, the embodiments disclosed herein should not necessarily be construed as limited to the shapes of specific illustrated regions, but should be construed to include, for example, deviations in shape resulting from manufacturing. In this way, the regions depicted in the drawings may be schematic in nature, and the shapes of these regions may not reflect the actual shapes of regions of the device, and as such, are not necessarily intended to have a limiting meaning.

[0041] As is conventional in the art, some embodiments may be illustrated and described in the accompanying drawings in terms of functional blocks, units, and / or modules. Those skilled in the art will appreciate that these blocks, units, and / or modules are physically implemented by electronic (or optical) circuits such as logic circuits, discrete components, microprocessors, wiring circuits, memory elements, and wiring connections formed using semiconductor-based or other manufacturing techniques. When the blocks, units, and / or modules are implemented by microprocessors or other similar hardware, they may be programmed and controlled using software (e.g., microcode) to perform the various functions discussed herein, and optionally, may be driven by firmware and / or software. Furthermore, each block, unit, and / or module may be implemented by dedicated hardware, or by a combination of dedicated hardware for performing some functions and processors (e.g., one or more programmed processors and associated circuitry) for performing other functions. Additionally, the blocks, units, and / or modules of some embodiments may be physically separated into two or more interacting and individual blocks, units, and / or modules without departing from the scope of the present invention. Additionally, the blocks, units, and / or modules of some embodiments may be physically combined into more complex blocks, units, and / or modules without departing from the scope of the present invention.

[0042] Unless otherwise defined, all terms (including technical or scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. Terms defined in commonly used dictionaries, such as terms defined in commonly used dictionaries, should be interpreted to have a meaning consistent with their meaning in the context of the relevant technology, and should not be interpreted in an idealistic or overly formal sense unless explicitly defined herein.

[0043] The present invention provides a light-emitting device comprising a substrate (110), a cover layer (120) disposed on an upper surface of the substrate (110) and forming at least one opening (122) exposing at least a portion of the upper surface of the substrate (110), a light-emitting element (130) disposed on an upper surface of the substrate (110) exposed through the opening (122), and a molding layer (140) covering the cover layer (120) and the light-emitting element (130). Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to the attached drawings.

[0044] The above substrate (110) is a circuit board on which a light-emitting element (130) is mounted on the upper surface, and has an insulating layer and wiring for electrical connection with the light-emitting element (130), and may include circuits for supplying power to and driving the light-emitting element (130).

[0045] A pad for mounting a light-emitting element (130) may be formed on the upper surface of the substrate (110), and a pad for mounting on another substrate (not shown, for example, a display substrate) may also be formed on the lower surface of the substrate (110).

[0046] The above substrate (110) can be formed into a multi-layer structure and can be formed into various thicknesses as needed.

[0047] The above cover layer (120) can have various configurations, such as a configuration that forms at least one opening (122) that exposes at least a portion of the upper surface of the substrate (110).

[0048] The above cover layer (120) is a layer that covers at least a portion of the upper surface of the substrate (110), and can be formed in close contact with the upper surface of the substrate (110).

[0049] The above cover layer (120) may be an insulating layer.

[0050] The above cover layer (120) can be formed on the upper surface of the substrate (110) through various processes if an opening (122) is formed that exposes a portion of the upper surface. For example, the cover layer (120) can be a layer formed on the upper surface of the substrate (100) through a PSR (Photo imageable Solder Resist) process.

[0051] Specifically, the cover layer (120) can be formed by applying ink (spray or silkscreen, etc.) to the upper surface of the substrate (110), curing the ink applied to the remaining area except for the area corresponding to the opening (122) by irradiating it with light (UV) (exposure and curing), and removing the uncured area of ​​the opening (122) to expose the upper surface of the substrate (110).

[0052] Additionally, the cover layer (120) may include a black pigment. For example, the cover layer (120) may be a black PSR coating layer.

[0053] The opening (122) of the above cover layer (120) is an opening for exposing the mounting area where the light-emitting element (130) is mounted on the upper surface of the substrate (110), and can be formed in various sizes and shapes.

[0054] A plurality of openings (122) may be formed on the cover layer (120), and one or more light-emitting elements (130) may be mounted in the openings (122). That is, one light-emitting element (130) may be mounted in one opening (122), or a plurality of light-emitting elements (130) may be mounted in one opening (122).

[0055] The above light-emitting element (130) is a light-emitting diode that is placed on the upper surface of the substrate (110) exposed through the opening (122), and can be configured in various ways.

[0056] Referring to FIG. 2, the light-emitting element (130) may include a transparent substrate (132) and a semiconductor layer (134) that is arranged on one surface of the transparent substrate (132) and generates light.

[0057] The above transparent substrate (132) may be a light-transmitting substrate such as PET, a glass substrate, quartz, or a sapphire substrate.

[0058] The above transparent substrate (132) is placed on the light emitting surface of the light emitting element (130), and light emitted from the light emitting element (130) can be emitted to the outside through the transparent substrate (132).

[0059] The above transparent substrate (132) may have an upper surface and a lower surface, and a semiconductor layer (134) may be arranged on one surface.

[0060] The above semiconductor layer (134) is a light-emitting structure that emits light having a preset peak wavelength and can be configured in various ways.

[0061] For example, the semiconductor layer (134) may be a light-emitting structure including a first conductive semiconductor layer (134a), an active layer (134b), and a second conductive semiconductor layer (134c).

[0062] The first conductive semiconductor layer (134a), the active layer (134b), and the second conductive semiconductor layer (134c) can be grown on a growth substrate in a chamber using a known method such as metal-organic chemical vapor deposition (MOCVD). The substrate can be various substrates that can be used for semiconductor growth, such as a gallium nitride substrate, a GaAs substrate, a Si substrate, a sapphire substrate, and particularly a patterned sapphire substrate. The growth substrate can be separated from the semiconductor layers using a technique such as mechanical polishing, laser lift-off, or chemical lift-off. However, the present invention is not limited thereto, and a portion of the substrate may remain to form at least a portion of the first conductive semiconductor layer (21).

[0063] In the case of a light-emitting element (130) that emits red light, the semiconductor layers (134) may include aluminum gallium arsenide (AlGaAs), gallium arsenide phosphide (GaAsP), aluminum gallium indium phosphide (AlGaInP), or gallium phosphide (GaP).

[0064] In the case of a light-emitting element (130) that emits green light, the semiconductor layers (134) may include indium gallium nitride (InGaN), gallium nitride (GaN), gallium phosphide (GaP), aluminum gallium indium phosphide (AlGaInP), or aluminum gallium phosphide (AlGaP).

[0065] In the case of a light-emitting element (130) that emits blue light, the semiconductor layer may include gallium nitride (GaN), indium gallium nitride (InGaN), or zinc selenide (ZnSe).

[0066] The first conductive type semiconductor layer (134a) and the second conductive type semiconductor layer (134c) have opposite polarities. When the first conductive type is n-type, the second conductive type is p-type, and when the first conductive type is p-type, the second conductive type is n-type.

[0067] For example, the first conductive semiconductor layer (134a) may include an n-type impurity (e.g., Si, Ge, Sn), and the second conductive semiconductor layer (134c) may include a p-type impurity (e.g., Mg, Sr, Ba).

[0068] Specifically, the first conductive semiconductor layer (134a) may include GaN or AlGaN containing Si as a dopant, and the second conductive semiconductor layer (134c) may include GaN or AlGaN containing Mg as a dopant.

[0069] Although the first conductive semiconductor layer (134a) and the second conductive semiconductor layer (134c) are each depicted as a single layer in the drawing, these layers may have a multilayer structure and may also include a superlattice layer.

[0070] The above active layer (134b) may include a single quantum well structure or a multiple quantum well structure (MQW), and the composition ratio of the nitride semiconductor may be adjusted to emit a desired wavelength. For example, the light-emitting element (130) may be configured to emit blue light, green light, red light, or ultraviolet light from the active layer (134b).

[0071] The second conductive semiconductor layer (134c) and the active layer (134b) have a mesa structure and can be placed on the first conductive semiconductor layer (134a).

[0072] The mesa includes a second conductive semiconductor layer (134c) and an active layer (134b), and may also include a portion of a first conductive semiconductor layer (134a). The mesa is positioned on a portion of the first conductive semiconductor layer (134a), and the upper surface of the first conductive semiconductor layer (21) may be exposed around the mesa.

[0073] At this time, the light-emitting element (130) may include an insulating layer (134f) that covers the first conductive semiconductor layer (134a) and the second conductive semiconductor layer (134c) and forms an opening in which two electrode pads (134d, 134e) are arranged.

[0074] The above two electrode pads (134d, 134e) can be electrically connected to the first conductive semiconductor layer (134a) and the second conductive semiconductor layer (134c), respectively, through the openings in the insulating layer (134f).

[0075] The electrode pads (134d, 134e) may be formed of a single layer or multi-layer metal. The electrode pads (134d, 134e) may be formed of a material such as a metal such as Al, Ti, Cr, Ni, Au, or an alloy thereof.

[0076] The above two electrode pads (134d, 134e) can be electrically connected to electrode pads formed on the upper surface of the substrate (110).

[0077] Although a light-emitting device (130) according to one embodiment of the present disclosure has been briefly described with reference to the drawings, the light-emitting device (130) may further include layers having additional functions in addition to the layers described above. For example, the light-emitting device (130) may further include various layers such as a reflective layer that reflects light, an additional insulating layer for insulating specific components, a solder prevention layer that prevents diffusion of solder, an ohmic layer, a contact layer, and the like.

[0078] In addition, the light-emitting element (130) can form a mesa in various shapes, and the positions and shapes of the electrode pads (134d, 134e) can also be changed in various ways. In addition, the light-emitting element (130) is not limited to a flip-chip structure.

[0079] In addition, the light emitting element (130) may include a single light emitting structure that each emits light of a single peak wavelength, but is not limited thereto, and as another example, it is also possible to form a single light emitting element (130) by vertically stacking a red light emitting structure, a blue light emitting structure, and a green light emitting structure or horizontally arranging them.

[0080] In addition, FIG. 2 is an example in which one semiconductor layer (134) is arranged on one transparent substrate (132), and illustrates a case in which each light-emitting element (130) has a separate transparent substrate (132), but the present invention is not limited thereto, and it is of course possible to form a plurality of semiconductor layers (134) on one transparent substrate (132).

[0081] Meanwhile, as the light emitting element (130) is mounted on the upper surface of the substrate (110) exposed by the opening (122) of the coating layer (120), the size and shape of the opening (122) on a plane can be configured in various ways depending on the number of light emitting elements (130) mounted in the opening (122) and the size and shape of the light emitting elements (130).

[0082] For example, based on the city of FIG. 1, the opening (122) may be formed in a rectangular shape with a length in the X-axis direction of K1 on a plane and a length in the Y-axis direction perpendicular to the X-axis direction of K2, but the shape of the opening (122) is not limited to a rectangle.

[0083] The X-axis direction length K1 and the Y-axis direction length K2 of the above opening (122) can be configured in various ways depending on the number of light-emitting elements (130) mounted in the opening (122) and the X-axis direction length W1 and the Y-axis direction length W2 of the light-emitting elements (130).

[0084] One light emitting element (130) may be placed within one opening (122), or multiple light emitting elements (130) may be placed at intervals. FIGS. 3A and 3B illustrate an example in which three light emitting elements (130) are placed in a row at intervals within one opening (122), and the cover layer (120) may form a boundary surrounding the outer edges of three neighboring light emitting elements (130).

[0085] Figures 3 to 6 illustrate examples in which both the X-axis direction length K1 and the Y-axis direction length K2 of the opening (122) are formed to be larger than the light-emitting element (130), thereby forming a gap between the cover layer (120) and the light-emitting element (130), but the present invention is not limited thereto.

[0086] For example, as shown in FIG. 7, if the electrode pads (134d, 134e) formed on the lower surface of the light-emitting element (130) can be positioned within the opening (122), the size of the opening (122) may be smaller than the size of the light-emitting element (130).

[0087] As shown in Fig. 7, when the X-axis direction length K1 of the opening (122) is formed to be smaller than the X-axis direction length W1 of the light-emitting element (130), and the size of the opening (122) is smaller than the size of the light-emitting element (130), there is an advantage in that the light-emitting element (130) can be mounted in a more accurate position within the opening (122).

[0088] Meanwhile, the thickness (T1) of the cover layer (120) is the length from the upper surface of the substrate (110) to the upper surface of the cover layer (1200), and can be formed to be considerably thinner than the thickness of the light-emitting element (130). At this time, the thickness (T1) of the cover layer (120) can be formed to be thicker than the thickness (T2) of the semiconductor layer (134) of the light-emitting element (130).

[0089] In addition, the upper surface of the cover layer (120) may be positioned at a position corresponding to or higher than the upper surface of the semiconductor layer (134). In this case, the color clarity of the light emitting device may be improved by allowing light emitted from the side of the semiconductor layer (134) to be blocked by the cover layer (120) and emitted upward.

[0090] The above molding layer (140) can have various configurations as a layer covering the cover layer (120) and the light-emitting element (130).

[0091] The above molding layer (140) may be formed as a single layer or may have a multi-layer structure.

[0092] As an example, when the molding layer (140) is formed as a single layer as illustrated in FIGS. 3A and 3B, the molding layer (140) may be a light-transmitting layer, such as a translucent or transparent layer for light emission. For example, the light-transmitting molding layer (140) may be formed by applying a transparent resin (e.g., epoxy or silicone) to the upper surface of the substrate (110) and curing it.

[0093] The molding layer (140) above includes a light-transmitting material and may further include a diffusion material for light diffusion. When the molding layer (140) includes a light-diffusion material, when light generated from the light-emitting element (130) is emitted upward, the light can be diffused and emitted through the molding layer (140), and accordingly, the light can be uniformly diffused in the light-emitting device.

[0094] Additionally, the light transmittance of the molding layer (140) may vary depending on the content of a diffusion agent for diffusing light. Accordingly, the thickness of the molding layer (140) may be determined taking the light transmittance into consideration.

[0095] Referring to FIG. 3a, the upper surface of the molding layer (140) is depicted as being flat, but a number of unevennesses may be formed on the upper surface of the molding layer (140) to form an uneven surface.

[0096] Meanwhile, a film layer (150) may be placed on the upper surface of the molding layer (140).

[0097] The above film layer (150) may be an anti-glare layer capable of preventing glare.

[0098] For example, the film layer (150) may be a film layer formed through matte treatment. Specifically, the film layer (150) may be a matte film layer that is surface-treated after a matte film attached to the molding layer (140) is attached to the molding layer (140).

[0099] The above film layer (150) can be formed thinner than the thickness of the molding layer (140), and can have various thicknesses depending on the thickness of the film attached to the upper surface of the molding layer (140), and it goes without saying that films of various thicknesses can be selectively attached.

[0100] An adhesive layer for film adhesion may be provided between the film layer (150) and the molding layer (140).

[0101] As another example, as illustrated in FIG. 4, when the molding layer (140) is formed in a multi-layer structure, the molding layer (140) may include a first molding layer (142) that exposes the upper surface of the light-emitting element (130) and covers at least a portion of the side surface of the light-emitting element (130), and a second molding layer (142) that covers the first molding layer (142) and the upper surface of the light-emitting element (130).

[0102] The first molding layer (142) exposes the upper surface of the light-emitting element (130) and is a layer that covers at least a portion of the side surface of the light-emitting element (130), and may include a light-reflecting material or a light-absorbing material.

[0103] The above first molding layer (142) may be an opaque layer and may include a black pigment to adjust the contrast of the display.

[0104] The first molding layer (142) may be formed by applying a molding agent to the upper portion of the substrate (110), and then liquefying it through compression and high-temperature treatment to fill the area around the light-emitting element (130). Alternatively, the first molding layer (142) may be a layer formed by curing a resin through UV treatment.

[0105] The first molding layer (142) may include a light-blocking function, and furthermore, may perform both a light-blocking function and a light-reflecting function. For example, the first molding layer (142) may be formed of a carbon black molding agent or a molding agent combining black and white.

[0106] However, the present invention is not limited thereto, and the first molding layer (142) may further include a light-absorbing function in addition to the light-reflecting function. For example, the first molding layer (142) may be formed of a white molding agent or a molding agent combining white and black. Accordingly, the contrast of the light emitted through the first molding layer (142) can be adjusted, and the brightness of the display can be improved.

[0107] Since the first molding layer (142) includes at least one of a light-blocking material and a light-reflecting material, the first molding layer (142) can expose at least a portion of the upper surface of the light-emitting element (130). That is, the first molding layer (142) is formed so as not to cover the entire upper surface of the light-emitting element (130), and can be arranged so as to cover at least a portion of the side surface of the light-emitting element (13).

[0108] At this time, the first molding layer (142) may cover the entire side surface of the light-emitting element (130), or may be formed at a height lower than the light-emitting element (130) so as not to cover a portion of the upper area of ​​the side surface of the light-emitting element (130).

[0109] Since the first molding layer (142) is positioned so as to cover at least a portion of the side surface of the light-emitting element (130) but not the upper surface thereof, light generated from the light-emitting element (130) and directed to the side surface can be reflected by the first molding layer (142) and induced to be emitted upward. Accordingly, the light extraction concentration in the upper direction can be increased, thereby improving light efficiency and brightness.

[0110] The lower portion of the light-emitting element (130), i.e., the space between the electrode pads (134d, 134e), may also be filled with the first molding layer (142). Accordingly, when the light generated from the light-emitting element (130) is directed downward, the first molding layer (142) can reflect the light and induce it to be emitted upward. Therefore, it may provide additional assistance in improving light extraction efficiency and brightness uniformity. Alternatively, it is also possible to configure the lower portion of the light-emitting element (130) as a space filled with air without the first molding layer (142).

[0111] Meanwhile, FIG. 4 illustrates that the first molding layer (142) exposes the entire upper surface of the light-emitting element (130), but the first molding layer (142) may be configured to expose only a portion of the upper surface of the light-emitting element (130).

[0112] For example, the first molding layer (142) exposes the central portion of the upper surface of the light emitting element (130) and extends to the upper edge of the light emitting element (130) so as to overlap at least a portion of the upper edge (corner side) of the light emitting element (130).

[0113] Meanwhile, the first molding layer (142) is a layer formed by curing a resin applied to the upper surface of the substrate (110), and the upper surface of the first molding layer (142) positioned between adjacent light-emitting elements (130) can form a curved surface due to the influence of the surface tension of the liquid material.

[0114] Depending on the amount of molding agent applied, the upper surface of the first molding layer (142) may form a concave surface, and the concave surface may have a lowest point (L) having the lowest height and a highest point (M) having the highest height.

[0115] Referring to Fig. 4, the concave surface can be formed in an asymmetrical shape on the left and right based on an imaginary vertical line (N) passing through the lowest point (L), and the left and right curvatures can also be formed differently from each other.

[0116] The second molding layer (144) can be configured in various ways as a light-transmitting layer covering the upper surface of the first molding layer (142) and the light-emitting element (130).

[0117] The second molding layer (144) may be a translucent or transparent layer for light emission. For example, a light-transmitting second molding layer (144) may be formed by applying a transparent resin (e.g., epoxy or silicone) to the upper surface of the first molding layer (142) and the light-emitting element (130) and curing the resin.

[0118] The second molding layer (144) includes a light-transmitting material and may further include a diffusion material for light diffusion. When the second molding layer (144) includes a light-diffusion material, when light generated from the light-emitting element (130) is emitted upward, the light can be diffused and emitted through the second molding layer (144), and accordingly, the light can be uniformly diffused in the light-emitting device.

[0119] Additionally, the light transmittance of the second molding layer (144) may vary depending on the content of a diffusion agent for diffusing light. Accordingly, the thickness of the second molding layer (144) may be determined taking the light transmittance into consideration.

[0120] Referring to FIG. 4, the upper surface of the second molding layer (144) is shown as being flat, but a number of unevennesses may be formed on the upper surface of the second molding layer (144) to form an uneven surface.

[0121] Meanwhile, a film layer (150) having the same or similar configuration as described above may be placed on the upper surface of the second molding layer (144).

[0122] Meanwhile, in the embodiment of FIG. 4, the thickness (D1) from the upper surface of the substrate (110) to the lowest point (L) of the concave surface of the first molding layer (142) may be configured to be thicker than the thickness (D2) from the lowest point (L) of the concave surface to the upper surface of the second molding layer (144).

[0123] In addition, the thickness (T1) of the cover layer (120) may be formed to be thicker than the thickness (T3) from the lowest point (L) of the concave surface of the first molding layer (142) to the highest point (M) of the concave surface. In addition, the thickness (T1) of the cover layer (120) may be formed to be thinner than the thickness from the upper surface of the cover layer (120) to the lowest point (L) of the concave surface.

[0124] In addition, the longitudinal width (W1) of the light emitting element (130) may be configured to be longer than the thickness (T4) from the upper surface of the light emitting element (130) to the upper surface of the second molding layer (144). Through this, the efficiency of the light emitted from the light emitting element (130) and transmitted through the second molding layer (144) can be maximized.

[0125] In addition, the thickness from the upper surface of the substrate (110) to the upper surface of the light-emitting element (130) may be formed to be thicker than the thickness (T4) from the light-emitting element (130) to the upper surface of the second molding layer (144). At this time, the thickness from the upper surface of the substrate (110) to the upper surface of the light-emitting element (130) may have a value that is less than twice the thickness (T2) to the upper surface of the second molding layer (144).

[0126] Next, FIG. 5 is another embodiment of a light-emitting device according to the present invention, which differs from FIGS. 3a to 4 in that one or more light-emitting elements (130) are mounted on a substrate (110) through a sub-substrate (101).

[0127] Since the light emitting elements (130) are directly mounted on the sub-substrate (101) and the sub-substrate (101) is arranged on the upper surface of the substrate (110), handling can be made easier compared to arranging the light emitting elements (130) on each substrate (110). That is, when a plurality of light emitting elements (130) are arranged on one sub-substrate (101), the plurality of light emitting elements (130) can be arranged on the substrate (110) by handling only one sub-substrate (101).

[0128] In the case of the light emitting device according to FIG. 5, the cover layer (120) described above can be formed on the sub-substrate (101) and thus placed on the upper side of the substrate (110).

[0129] The above cover layer (120) may be formed around the edge of the sub-substrate (101) as illustrated in FIGS. 5A and 5B to form one opening (122) therein. A plurality of light-emitting elements (130) may be arranged inside the opening (122). Alternatively, the cover layer (120) may be configured to form a plurality of openings (122), as illustrated in FIG. 6, and one light-emitting element (130) may be arranged in each opening (122).

[0130] The above-described molding part (140) can be formed on the upper surface of the cover layer (120) and the light-emitting element (130).

[0131] Meanwhile, a separate light control layer (170) may be further formed on the upper portion of the cover layer (120), as shown in FIGS. 5a to 6.

[0132] The above light control layer (170) is formed along the edge of the sub-substrate (101) and may be formed high to have a dam shape. The thickness of the light control layer (170) is thicker than the thickness of the cover layer (120), but the upper surface of the light control layer (170) may be positioned lower than the upper surface of the light emitting element (130). Although not illustrated, it is also possible for the upper surface of the light control layer (170) to be positioned higher than the upper surface of the light emitting element (130).

[0133] The above light control layer (170) may include a function of blocking light, and further may perform both a light blocking function and a light reflection function.

[0134] For example, the light control layer (170) may be formed of a carbon black molding agent or a molding agent combining black and white. However, the present invention is not limited thereto, and the light control layer (170) may further include a light absorption function in addition to a light reflection function. For example, the light control layer (170) may be formed of a white molding agent or a molding agent combining white and black. Accordingly, the contrast of the light emitted through the light control layer (170) may be adjusted, and the brightness of the display may be improved.

[0135] Referring to Fig. 1, a light emitting device according to the present invention can form one pixel (P) with three light emitting elements (130) that emit light of different peak wavelengths and are arranged in a first direction on a plane. Here, the first direction may be the Y-axis direction based on Fig. 1, and a direction perpendicular to the first direction may be the X-axis direction based on Fig. 1 as a second direction.

[0136] The three light-emitting elements (130) constituting one pixel (P) may be light-emitting diodes that emit red, green, and blue light, respectively.

[0137] As illustrated in Fig. 1, the light-emitting device may include a plurality of pixels (P) arranged in a grid shape along the first direction and a second direction perpendicular to the first direction. The plurality of pixels (P) may be arranged on a plane so that light can be uniformly emitted.

[0138] Specifically, the maximum distance (S1) between two light-emitting elements (130) at both ends within the pixel (P) based on the first direction may be configured to be longer than the shortest distance (S2) between two neighboring pixels (P) based on the second direction.

[0139] In addition, the distance (S3) between two neighboring light-emitting elements (130) within the pixel (P) based on the first direction may be configured to be smaller than the shortest distance (S4) between two neighboring pixels (P) based on the first direction.

[0140] Meanwhile, the red, green, and blue light-emitting elements (130) that constitute one pixel (pixel, P) can be managed in terms of light quantity ratio (e.g., 3:6:1 for RGB, respectively), peak wavelength, and dominant wavelength to match the maximum visible wavelength of 550 nm.

[0141] Specifically, the light-emitting element (130) that emits blue light (B) is a blue light-emitting diode having a center wavelength within the blue wavelength range, and the difference between the center wavelength and the dominant wavelength may be between 2 nm and 15 nm. Specifically, the blue light-emitting diode may have a center wavelength different from 455 nm to 475 nm, and may have a dominant wavelength between 460 nm and 480 nm. The center wavelength of the blue light-emitting diode may be a shorter wavelength than the dominant wavelength.

[0142] The light-emitting element (130) emitting green light (G) may be a green light-emitting diode having a center wavelength within the green wavelength range, and the difference between the center wavelength and the dominant wavelength of the green light-emitting diode may be between 5 and 20 nm. Specifically, the green light-emitting diode may have a center wavelength between 520 nm and 540 nm, and a dominant wavelength between 525 nm and 545 nm. The center wavelength of the green light-emitting diode may be a shorter wavelength than the dominant wavelength.

[0143] The light emitting element (130) emitting red light (R) may be a red light emitting diode having a center wavelength (peak wavelength) within a red wavelength range, and the difference between the center wavelength and the dominant wavelength of the red light emitting diode may be between 5 and 20 nm. Specifically, the red light emitting diode may have a center wavelength between 620 nm and 640 nm, and a dominant wavelength between 610 nm and 630 nm. The center wavelength of the red light emitting diode may be a wavelength longer than the dominant wavelength.

[0144] The deviations between the central wavelength and the dominant wavelength of each of the above light-emitting devices (130) may have different deviations. For example, the deviation between the central wavelength and the dominant wavelength of a blue light-emitting diode may have a smaller deviation than the deviation between the central wavelength and the dominant wavelength of a green light-emitting diode. The deviation between the central wavelength and the dominant wavelength of a green light-emitting diode may have a smaller deviation than the deviation between the central wavelength and the dominant wavelength of a red light-emitting diode. In this way, by managing the deviations between the central wavelength and the dominant wavelength of the blue light-emitting diode, the green light-emitting diode, and the red light-emitting diode, the color purity and visibility of the color that implements the image of the display can be improved.

[0145] In addition, the light emitting device according to the present invention is configured to include a substrate (110), a cover layer (120), and a molding layer (140), and may be configured in various combinations by additionally including at least one or more of other components, for example, a film layer (150), a light control layer (170), and a sub-substrate (101).

[0146] The shape, thickness (T1), material, and opening (122) of the above cover layer (120) can be configured independently from other components.

[0147] The above molding layer (140) may have a single-layer or multi-layer structure, and even when the molding layer (140) is configured as a multi-layer structure (first and second molding layers (142, 144)), an embodiment in which the above-described light control layer (170) is further added is also possible. The material, added filler, thickness, and layer structure of the molding layer (140) may be configured independently from other components.

[0148] Even if the above light emitting device is configured to include a sub-substrate (101), the cover layer (120) and the molding layer (140) described with reference to FIGS. 3a to 4 may be applied in the same or similar manner.

[0149] Meanwhile, the light-emitting devices of the various embodiments according to the present invention described above can constitute a display device for display. The light-emitting devices described above are display modules, and the display device can include one or more display modules.

[0150] Specifically, the display device may include at least one display module, and the display module may include a substrate (110), a cover layer (120) disposed on an upper surface of the substrate (110) and forming at least one opening (122) exposing at least a portion of the upper surface of the substrate (110), a light-emitting element (130) disposed on an upper surface of the substrate (110) exposed through the opening (122), and a molding layer (140) covering the cover layer (120) and the light-emitting element (130).

[0151] When configuring a display device, display screens of various sizes can be implemented by arranging the sides of a plurality of display modules in contact with each other.

[0152] FIGS. 8a and 8b are graphs showing the color difference by position of the light-emitting device and display device according to the present invention, and it can be confirmed that the color difference by position is 0.002 or less in the horizontal direction and 0.015 or less in the vertical direction, so that the uniformity of brightness and color by position is greatly improved.

[0153]

[0154] Although the present invention has been described above with reference to preferred embodiments thereof, it will be understood by those skilled in the art or having ordinary knowledge in the art that various modifications and changes to the present invention can be made without departing from the spirit and technical scope of the present invention as set forth in the claims to be described below.

[0155] Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification, but should be defined by the patent claims.

Claims

1. Substrate; A cover layer disposed on the upper surface of the substrate and forming at least one opening exposing at least a portion of the upper surface of the substrate; A light emitting element disposed on the upper surface of the substrate exposed through the above opening; and A light-emitting device comprising a molding layer covering the cover layer and the light-emitting element.

2. In claim 1, The above cover layer is a light-emitting device which is a coating layer containing black pigment.

3. In claim 1, The above light-emitting element includes a transparent substrate and a semiconductor layer that is arranged on one surface of the transparent substrate and generates light. A light emitting device wherein the thickness of the cover layer is thicker than the thickness of the semiconductor layer.

4. In claim 1, A light emitting device in which the size of the opening on the plane is smaller than the size of the light emitting element.

5. In claim 1, A light-emitting device comprising a first molding layer that exposes the upper surface of the light-emitting element and covers at least a portion of a side surface of the light-emitting element, and a second molding layer that covers the first molding layer and the upper surface of the light-emitting element.

6. In claim 5, A light-emitting device wherein the first molding layer includes at least one of a light-reflecting material and a light-absorbing material.

7. In claim 5, A light-emitting device in which the second molding layer is a light-transmitting layer.

8. In claim 5, A light emitting device in which the upper surface of the first molding layer positioned between two adjacent light emitting elements forms a concave surface.

9. In claim 5, A light emitting device in which the thickness from the upper surface of the substrate to the lowest point of the concave surface of the first molding layer is thicker than the thickness from the lowest point of the concave surface to the upper surface of the second molding layer.

10. In claim 5, A light emitting device in which the thickness of the cover layer is thicker than the thickness from the lowest point of the concave surface of the first molding layer to the highest point of the concave surface.

11. In claim 5, A light emitting device in which the longitudinal width of the light emitting element is longer than the thickness from the upper surface of the light emitting element to the upper surface of the second molding layer.

12. In claim 1, Three light-emitting elements that emit light of different peak wavelengths and are arranged in the first direction on a plane form one pixel. The light emitting device comprises a plurality of pixels arranged in a grid shape along the first direction and a second direction perpendicular to the first direction.

13. In claim 12, A light-emitting device in which the maximum distance between two light-emitting elements at opposite ends within the pixel based on the first direction is longer than the shortest distance between two neighboring pixels based on the second direction.

14. In claim 12, A light-emitting device in which a distance between two neighboring light-emitting elements within the pixel with respect to the first direction is smaller than the shortest distance between two neighboring pixels with respect to the first direction.

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