Backlight unit and display device including the same

Abstract

Embodiments of the present disclosure relate to a backlight unit and a display device including the backlight unit. Specifically, a backlight unit with enhanced image quality and a display device including the backlight unit can be provided, the backlight unit including: at least one light source disposed on a printed circuit and spaced apart from each other; a reflector disposed on the printed circuit and including at least one protrusion disposed to correspond to the at least one light source; and a diffusion plate disposed on the reflector, wherein the at least one protrusion respectively surrounds the at least one light source and wherein the protrusion includes at least one opening in a side surface thereof.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to Korean Patent Application No. 10-2021-0178167, filed on December 13, 2021, which is hereby incorporated by reference for all purposes as if fully set forth herein. Technical Field

[0003] Embodiments of the present disclosure relate to a backlight unit and a display device including the backlight unit. Background Art

[0004] A display device may include a display panel having a plurality of sub-pixels and various driving circuits for driving elements provided in the sub-pixels. Depending on the type of the display device, the display device may include a backlight unit for supplying light to the display panel.

[0005] The backlight unit may include a plurality of light sources and a plurality of optical members. The backlight unit may be provided on a surface opposite to a surface where the display panel displays an image to supply light to the display panel. Summary of the Invention

[0006] Since the backlight unit includes a plurality of light sources and a plurality of optical members, the display device may be thickened.

[0007] Increasing the amount of light supplied to a display panel can improve its brightness. In order to increase the amount of light supplied to the display panel, a high drive current is required. However, increasing the drive current can damage optical components. The present inventors have invented a backlight unit and a display device including the backlight unit. These backlight units can reduce thickness, improve image quality, and maintain optical properties without damaging optical components despite being driven with a high drive current.

[0008] Embodiments of the present disclosure relate to a backlight unit that provides light to a display panel and a display device including the same, which can enhance image quality of the backlight unit while reducing thickness.

[0009] Embodiments of the present disclosure may provide a backlight unit and a display device including the backlight unit, the backlight unit including: at least one light source arranged on a printed circuit and spaced apart from each other; a reflector arranged on the printed circuit and including at least one protrusion arranged to correspond to the at least one light source; and a diffusion plate arranged on the reflector, wherein the at least one protrusion respectively surrounds the at least one light source, and wherein the protrusion includes at least one opening in a side surface of the protrusion.

[0010] Embodiments of the present disclosure may provide a backlight unit and a display device including the backlight unit, the backlight unit including: at least one light source provided on a printed circuit and spaced apart from each other; a reflector provided on the printed circuit and including at least one protrusion provided to correspond to the at least one light source; a diffusion plate provided on the reflector; a color conversion film provided on the diffusion plate; and a display panel provided on the color conversion film, wherein the at least one protrusion respectively surrounds the at least one light source and wherein the protrusion includes at least one opening in a side surface of the protrusion.

[0011] According to an embodiment of the present disclosure, a backlight unit for providing light to a display panel and a display device including the backlight unit can be provided, which can enhance the image quality of the backlight unit while reducing the thickness by allowing a reflector to include at least one protrusion and allowing the protrusion to have at least one opening. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The above and other objects, features and advantages of the present disclosure will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

[0013] Figure 1 is a diagram schematically illustrating a configuration of a display device according to one embodiment of the present disclosure;

[0014] Figure 2 is a diagram illustrating an example of a structure of a backlight unit included in a display device according to one embodiment of the present disclosure;

[0015] Figure 3 is a diagram showing the structure of a reflector of a backlight unit;

[0016] Figure 4 is a plan view showing a protrusion of a reflector according to one embodiment of the present disclosure;

[0017] Figure 5 is a diagram illustrating another shape of a protrusion of a reflector according to an embodiment of the present disclosure;

[0018] Figure 6 is a side view showing the structure of a protrusion of a reflector according to one embodiment of the present disclosure;

[0019] Figure 7 is a diagram illustrating an arrangement relationship between a reflector and a light source and a light path according to the arrangement relationship according to one embodiment of the present disclosure;

[0020] Figure 8 is a diagram illustrating an arrangement structure of a reflector and a light source included in a backlight unit according to one embodiment of the present disclosure;

[0021] Figure 9 and Figure 10 is a diagram illustrating another structure of a protrusion of a reflector according to one embodiment of the present disclosure; and

[0022] Figure 11 It shows Figure 10 A side view of the protruding structure of the reflector. DETAILED DESCRIPTION

[0023] In the following description of examples or embodiments of the present disclosure, reference will be made to the accompanying drawings, in which specific examples or embodiments that can be implemented are shown by way of illustration, and in the accompanying drawings, the same reference numerals and symbols may be used to represent the same or similar parts, even when these parts are shown in different drawings from each other. In addition, in the following description of examples or embodiments of the present disclosure, when it is determined that a detailed description of known functions and components incorporated herein may make the subject matter of some embodiments of the present disclosure quite unclear, the description will be omitted. Terms such as "including", "having", "comprising", "consisting of", and "formed of" used herein are generally intended to allow for the addition of other components unless these terms are used with the term "only". As used herein, the singular form is intended to include the plural form unless the context clearly indicates otherwise.

[0024] Terms such as "first," "second," "A," "B," "(A)," or "(B)" may be used herein to describe elements of the present disclosure. Each of these terms is not used to limit the nature, order, sequence, or number of the elements, but is only used to distinguish the corresponding element from other elements.

[0025] When it is mentioned that a first element is “connected or coupled to” a second element, “contacts or overlaps with” the second element, etc., it should be interpreted that the first element may not only be “directly connected or coupled to” the second element or “directly contact or overlap with” the second element, but also that a third element may be “interposed” between the first and second elements, or that the first and second elements may be “connected or coupled to”, “contacts or overlaps” each other via a fourth element, etc. Here, the second element may be included in at least one element of the two or more elements that are “connected or coupled to”, “contacts or overlaps”, etc., each other.

[0026] When time relative terms such as “after,” “subsequently,” “next,” “before,” etc. are used to describe a process or operation of an element or configuration, or a process or step in an operation, process, or method of manufacture, these terms may be used to describe non-sequential or non-sequential processes or operations unless used with the terms “directly” or “immediately thereafter.”

[0027] In addition, when any dimension, relative size, etc. is mentioned, it should be understood that, even when no relevant description is specified, the numerical value or corresponding information (e.g., level, range, etc.) of the element or feature also includes a tolerance or error range that may be caused by various factors (e.g., process factors, internal or external influences, noise, etc.). In addition, the term "may" fully encompasses all meanings of the term "can."

[0028] Hereinafter, various embodiments of the present disclosure are described in detail with reference to the accompanying drawings.

[0029] Figure 1 is a diagram schematically illustrating a configuration of a display device 100 according to various embodiments of the present disclosure.

[0030] Reference Figure 1 The display device 100 may include a display panel (PNL) 110 including an active area AA and a non-active area NA, a gate driving circuit 120 , a data driving circuit 130 , and a controller 140 for driving the display panel 110 .

[0031] The display panel 110 may include a plurality of gate lines GL, a plurality of data lines DL, and sub-pixels SP at intersections of the gate lines GL and the data lines DL.

[0032] The gate driving circuit 120 may be controlled by the controller 140 to sequentially output scan signals to a plurality of gate lines GL disposed in the display panel 110 , thereby controlling a driving timing of the sub-pixels SP.

[0033] The gate driving circuit 120 may include one or more gate driver integrated circuits (GDICs). Depending on the driving scheme, the gate driving circuit 120 may be located on only one side or each of two opposing sides of the display panel 110.

[0034] Each gate driver integrated circuit (GDIC) may be connected to a bonding pad of the display panel 110 in a tape automated bonding (TAB) or chip on glass (COG) scheme, or may be implemented in a gate in panel (GIP) type to be directly provided in the display panel 110, or in some cases, may be integrated in the display panel 110. Each gate driver integrated circuit (GDIC) may also be implemented in a chip on film (COF) scheme to be mounted on a film connected to the display panel 110.

[0035] The data driving circuit 130 receives image data DATA from the controller 140 and converts the image data into analog data voltages. The data driving circuit 130 outputs a data voltage to each data line DL according to the timing of applying a scan signal via the gate line GL, so that each subpixel SP can represent brightness according to the image data.

[0036] The data driving circuit 130 may include one or more source driver integrated circuits (SDICs).

[0037] Each source driver integrated circuit (SDIC) may include, for example, a shift register, a latch circuit, a digital-to-analog converter, and an output buffer.

[0038] Each source driver integrated circuit (SDIC) may be connected to a bonding pad of the display panel 110 in a TAB or COG scheme, or may be directly provided in the display panel 110, or in some cases, may be integrated in the display panel 110. Each source driver integrated circuit (SDIC) may be implemented in a COF scheme, in which case each source driver integrated circuit (SDIC) may be mounted on a film connected to the display panel 110 and electrically connected to the display panel 110 via wiring on the film.

[0039] The controller 140 supplies various control signals to the gate driving circuit 120 and the data driving circuit 130 , and controls operations of the gate driving circuit 120 and the data driving circuit 130 .

[0040] The controller 140 may be mounted on a printed circuit board or a flexible printed circuit board, and may be electrically connected to the gate driving circuit 120 and the data driving circuit 130 through the printed circuit board or the flexible printed circuit.

[0041] The controller 140 enables the gate driving circuit 120 to output scanning signals according to the timing of implementing each frame, converts image data received from the outside to meet the data signal format used by the data driving circuit 130, and outputs the obtained image data to the data driving circuit 130.

[0042] Along with the image data, the controller 140 receives various timing signals including a vertical synchronization signal VSYNC, a horizontal synchronization signal HSYNC, an input data enable signal DE, and a clock signal from the outside (eg, a host system).

[0043] The controller 140 may generate various control signals using timing signals received from the outside, and output the control signals to the gate driving circuit 120 and the data driving circuit 130 .

[0044] As an example, in order to control the gate driving circuit 120 , the controller 140 outputs various gate control signals GCS including a gate start pulse GSP, a gate shift clock GSC, and a gate output enable signal GOE.

[0045] The gate start pulse GSP controls the operation start timing of one or more gate driver integrated circuits GDIC constituting the gate drive circuit 120. The gate shift clock GSC is a clock signal commonly input to the one or more gate driver integrated circuits GDIC and controls the shift timing of the scan signal. The gate output enable signal GOE specifies timing information for the one or more gate driver integrated circuits GDIC.

[0046] In order to control the data driving circuit 130 , the controller 140 outputs various data control signals DCS including, for example, a source start pulse SSP, a source sampling clock SSC, and a source output enable signal SOE.

[0047] The source start pulse SSP controls the data sampling start timing of one or more source driver integrated circuits (SDICs) that make up the data driver circuit 130. The source sampling clock SSC is a clock signal used to control the data sampling timing of each source driver integrated circuit (SDIC). The source output enable signal SOE controls the output timing of the data driver circuit 130.

[0048] The controller 140 may control the brightness of each area of ​​the display panel 110 individually by controlling the light emitting operation of the backlight unit of the display apparatus 100 through a local dimming technique.

[0049] The display device 100 may further include a power management integrated circuit that supplies various voltages or currents to, for example, the display panel 110 , the gate driving circuit 120 , and the data driving circuit 130 , or controls the various voltages or currents to be supplied.

[0050] Each sub-pixel SP may be a region defined by the intersection of the gate line GL and the data line DL, and liquid crystal or a light emitting element may be disposed in each sub-pixel SP depending on the type of the display device 100 .

[0051] As an example, when the display device 100 is a liquid crystal display device, the display device 100 may include a light source device, such as a backlight unit, that emits light toward the display panel 110. Liquid crystals are provided in the subpixels SP of the display panel 110. The arrangement of the liquid crystals can be adjusted by an electric field created when a data voltage is applied to each subpixel SP, thereby representing the brightness of each image data and displaying an image.

[0052] Figure 2 is a diagram illustrating an example of a structure of a backlight unit included in the display device 100 according to an embodiment of the present disclosure. Figure 3 is a diagram showing the structure of a reflector of a backlight unit.

[0053] Reference Figure 2, the display device 100 according to an embodiment of the present disclosure may include a display panel 110 and a backlight unit that is disposed under the display panel 110 and supplies light to the display panel 110 .

[0054] For example, the backlight unit may include a plurality of light sources 240 disposed on a printed circuit 220. The printed circuit 220 may be disposed on the bottom cover 210.

[0055] The guide panel 290 for supporting the display panel 110 may be disposed outside a region where the light source 240 and the optical members are disposed on the bottom cover 210 .

[0056] The light source 240 may include a light emitting portion 241 that emits light and an electrode portion 242 to which a signal for driving the light emitting portion 241 is applied.

[0057] The light source 240 may be, for example, a light emitting diode (LED), a small LED, or a micro LED (μLED). Therefore, the light source 240 in the form of a chip may be provided to be mounted on the printed circuit 220, thereby reducing the thickness of the backlight unit.

[0058] The light source 240 may emit white light, and in some cases, may emit light of a specific wavelength band. For example, the light source 240 may emit blue light. The blue light may be excited by an optical member provided on the light source 240 to supply white light to the display panel 110.

[0059] The reflector 230 may be disposed on the printed circuit 220 .

[0060] The reflector 230 may include at least one protrusion 231 and at least one vertical portion 232 .

[0061] The protrusion 231 of the reflector 230 may overlap with the at least one light source 240 .

[0062] Specifically, if Figure 2 As shown, at least one light source 240 may be disposed in a protrusion 231 provided in the reflector 230 .

[0063] Reference Figure 3 The reflector 230 may include a bottom portion 310 and a protrusion 231 , which is a portion protruding from the bottom portion 310 .

[0064] The protrusion 231 may have a dome shape, but the shape of the protrusion 231 according to an embodiment of the present disclosure is not limited thereto.

[0065] The protrusion 231 may include at least one opening 337 in a side surface.

[0066] For example, Figure 3As shown, one protrusion 231 may include four openings 337 .

[0067] The protrusion 231 may include a support portion 336 for supporting an upper portion 335 of the protrusion 231 .

[0068] For example, Figure 3 As shown, one protrusion 231 may include four supporting portions 336 .

[0069] Figure 3 A structure in which one protrusion 231 includes four openings 337 and four support portions 336 is shown, but the structure of the protrusion 231 according to an embodiment of the present disclosure is not limited thereto.

[0070] In at least one protrusion 231 provided in the reflector 230 , the number of openings 337 and the number of support portions 336 may correspond to each other.

[0071] In addition, despite Figure 3 A structure is shown in which the number of openings 337 is the same as the number of support portions 336 provided in each of the plurality of protrusions 231 , but the structure of the protrusion 231 according to an embodiment of the present disclosure is not limited thereto.

[0072] For example, one reflector 230 may include protrusions 231 having different numbers of openings 337 and supports 336 .

[0073] Reference Figure 2 and Figure 3 , at least one light source 240 may be disposed inside the protrusion 231 of the reflector 230. Light emitted from the light source 240 may be emitted to the outside through the opening 337 in the protrusion 231 without being confined within the protrusion 231.

[0074] Reference Figure 2 , the reflector 230 may include at least one vertical portion 232 .

[0075] In this case, the vertical portion 232 may be a region where the reflector 230 extends toward the display panel 110 .

[0076] The vertical portion 232 may be provided on one side of the bottom cover 210 .

[0077] The vertical portion 232 may reflect light emitted in a transverse direction of the light source 240 to the front surface of the backlight unit, thereby further improving light efficiency of the backlight unit.

[0078] In order to uniformly distribute the light emitted from the light source 240 , a lens surrounding the light source 240 may be used.

[0079] However, when a lens is employed in a backlight unit, the backlight unit may be thickened. In addition, when the light source 240 is a small-sized miniature light emitting diode (mini-LED) or micro-light emitting diode (μLED), it may be difficult to manufacture a lens surrounding the light source 240.

[0080] Therefore, a component capable of uniformly diffusing light emitted from the light source 240 to the backlight unit is required.

[0081] The light emitted from the light source 240 can be dispersed by applying a reflective pattern under the diffuser plate 280, but the position of the reflective pattern may change due to the shrinkage and expansion of the sheet provided with the reflective pattern. In this case, the light emitted from the light source 240 may not be properly diffused due to the misalignment between the light source 240 and the reflective pattern, and thus the image quality may be reduced.

[0082] The backlight unit according to an embodiment of the present disclosure employs the reflector 230 including at least one protrusion 231 , and thus may be thinned and uniformly disperse light from the light source 240 .

[0083] Reference Figure 2 and Figure 3 , the upper portion 335 of the protrusion 231 of the reflector 230 may be located on the light source 240 .

[0084] The upper portion 335 of the protrusion 231 may diffuse light emitted from the light source 240 so that the light is emitted in a horizontal direction and an oblique direction.

[0085] In other words, since the upper portion 335 of the protrusion 231 is disposed in the region having the highest intensity of light emitted from the light source 240, the brightness deviation between the region where the light source 240 is disposed (having more light) and the region between the light sources 240 (having less light) can be reduced.

[0086] Therefore, the image quality of the backlight unit can be improved by adjusting the direction of light emitted from light source 240 by upper portion 335 of protrusion 231. In other words, light emitted from light source 240 can be scattered, reflected, diffracted or transmitted by upper portion 335 of protrusion 231, thereby improving the brightness uniformity of the backlight unit.

[0087] Furthermore, since the light emitted from the light source 240 is appropriately scattered, reflected, diffracted, or transmitted, there is no need to increase the driving current of the light source to adjust the brightness.

[0088] A diffusion plate 280 for diffusing light from below the reflector 230 may be provided on the reflector 230 .

[0089] A color conversion sheet 281 for changing a wavelength band of light emitted from the light source 240 may be disposed on the diffusion plate 280. An optical sheet 285 may be disposed on the color conversion sheet 281.

[0090] For example, the optical sheet 285 may include a prism sheet 286 and a diffusion sheet 287. The prism sheet 286 may be disposed on the color conversion sheet 281, and the diffusion sheet 287 may be disposed on the prism sheet 286.

[0091] The display panel 110 may be disposed on the optical sheet 285. The display panel 110 may include an upper substrate 211 and a lower substrate 212.

[0092] The lower polarizing plate 251 may be disposed under the lower substrate 212 , and the upper polarizing plate 252 may be disposed on the upper substrate 211 .

[0093] A cover glass 260 may be disposed on the upper polarizing plate 252 .

[0094] The positions where the diffusion plate 280 and the color conversion sheet 281 are provided may be interchanged.

[0095] As described above, the diffusion plate 280 may serve to diffuse light emitted from the light source 240 .

[0096] The color conversion sheet 281 may emit light of a specific wavelength band in response to incident light.

[0097] For example, when the light source 240 emits light of a first wavelength band (e.g., blue light), the color conversion sheet 281 may react to the incident light and emit light of a second wavelength band (e.g., green light) and light of a third wavelength (e.g., red light). Thus, light of a white wavelength band may be supplied to the display panel 110 through the color conversion sheet 281.

[0098] In some cases, the color conversion sheet 281 may be provided only in a partial area on the diffusion plate 280 .

[0099] For example, when the light source 240 emits blue light, the color conversion sheet 281 may be provided only in an area of ​​the display panel 110 except for an area corresponding to an area where the blue sub-pixel SP is provided. In other words, light that does not pass through the color conversion sheet 281 may reach the blue sub-pixel SP of the display panel 110.

[0100] Depending on the light source 240 , the color conversion sheet 281 may not be provided.

[0101] For example, when the light source 240 emits white light or a color conversion film emitting green and red light is coated on the light emitting surface of the light source 240 emitting blue light, the color conversion sheet 281 may not be provided.

[0102] Therefore, the embodiment of the present disclosure may provide a backlight unit satisfying image quality by including the reflector 230 including the protrusion 231 positioned corresponding to the light source 240 .

[0103] Figure 4 is a plan view illustrating a protrusion of a reflector according to an embodiment of the present disclosure. Figure 5 is a diagram illustrating another shape of a protrusion of a reflector according to an embodiment of the present disclosure.

[0104] The following description will not be repeated for configurations and effects that are substantially the same as those described above. In the following description, the same reference numerals may be used to denote elements or components that are the same as those described in the above embodiment.

[0105] Reference Figure 4 , the protrusion 231 of the reflector 230 according to an embodiment of the present disclosure may be a portion protruding from the bottom 310 of the reflector 230 .

[0106] The protrusion 231 of the reflector 230 may have an elliptical shape in a plan view.

[0107] However, the shape of the protrusion 231 according to an embodiment of the present disclosure is not limited thereto, and the shape of the protrusion 231 may vary according to the shape of the light source provided inside the protrusion 231 .

[0108] For example, Figure 5 As shown, the protrusion 231 of the reflector 230 may be shaped like a circle in a plan view.

[0109] like Figure 4 and Figure 5 As shown, the diameter of the protrusion 231 may increase toward the base 310 .

[0110] Therefore, in a process of manufacturing the backlight unit, it is possible to prevent the light source 240 from being damaged due to the contact of the support portion 336 of the reflector 230 with the light source 240 .

[0111] Reference Figure 4 and Figure 5 , one protrusion 231 may include a plurality of openings 337 in a side surface thereof.

[0112] For example, the protrusion 231 may include a first opening 431 , a second opening 432 , a third opening 433 , and a fourth opening 434 .

[0113] The first to fourth openings 431 , 432 , 433 , and 434 may be spaced apart from one another.

[0114] The first opening 431 and the second opening 432 may be disposed to face each other. The third opening 433 and the fourth opening 434 may be disposed to face each other.

[0115] The support portion 336 may be provided between two adjacent openings among the openings 431 , 432 , 433 , and 434 .

[0116] In other words, the support portion 336 may serve to support the upper portion 335 of the protrusion 231 having the plurality of openings 337 in the side surface thereof, and to separate the plurality of openings.

[0117] The support portion 336 may be integrally formed with the upper portion 335 , but the structure of the protrusion 231 according to an embodiment of the present disclosure is not limited thereto.

[0118] The following describes an arrangement relationship between the reflector 230 and the light source 240 and a path of light emitted from the light source 240 according to an embodiment of the present disclosure.

[0119] Figure 6 is a side view illustrating the structure of a protrusion of a reflector according to an embodiment of the present disclosure. Figure 7 is a diagram illustrating an arrangement relationship between a reflector and a light source and a light path according to the arrangement relationship according to an embodiment of the present disclosure.

[0120] The following description will not be repeated for configurations and effects that are substantially the same as those described above. In the following description, the same reference numerals may be used to denote elements or components that are the same as those described in the above embodiment.

[0121] like Figure 6 As shown, the surface of the protrusion 231 of the reflector 230 may be in a circular shape.

[0122] When the protrusion 231 includes edges (lines forming boundaries between polyhedral surfaces), the protrusion 231 may be difficult to form and stress may be concentrated in the edges, thereby increasing the possibility of cracks, resulting in reduced reliability of the reflector 230 .

[0123] In the reflector 230 , at least one first hole 610 may be provided in a region of the bottom 310 corresponding to a region where the protrusion 231 is provided.

[0124] like Figure 7 As shown, the printed circuit 220 and the at least one light source 240 disposed on the printed circuit 220 may be disposed in a first hole 610 disposed in the bottom 310 .

[0125] Reference Figure 6 , a height H1 of the opening 337 provided in one protrusion 231 may be lower than a height H2 of the entire protrusion 231 .

[0126] Here, the height H1 of the opening 337 and the height H2 of the entire protrusion 231 mean the shortest length in a direction in which the color conversion sheet 281 is stacked on the diffusion plate 280 .

[0127] Therefore, the upper portion 355 of the protrusion 231 may be provided not only on the upper surface of the protrusion 231 but also on a portion of the side surface.

[0128] The upper portion 355 of the protrusion 231 may be connected to one end of the support portion 336 and may be integrally formed with the support portion 336 .

[0129] Reference Figure 6 and Figure 7 , light may be emitted in all directions from the light source 240. The region where the light source 240 is disposed may have a large amount of light, and the region between the light source 240 and another light source 240 adjacent to the light source 240 may have a small amount of light.

[0130] like Figure 7 As shown, light L1 (hereinafter, referred to as first light) reaching the upper portion 355 of the protrusion 231 among the light emitted from the light source 240 may be reflected and thus change a path.

[0131] The first light L1 may be emitted to the outside of the protrusion 231 through at least one 431 , 432 , 433 , and 434 of the plurality of openings 337 of the protrusion 231 .

[0132] The first light L1 may reach the diffusion plate 280 after changing its path through the bottom portion 310 of the reflector 230, or may reach the diffusion plate 280 after changing its path through the vertical portion 232 of the reflector 230. Alternatively, the first light L1 may change its path through the support portion 336 or the upper portion 335 of another protrusion 231 adjacent thereto and then reach the diffusion plate 280.

[0133] Therefore, since the upper portion 355 of the protrusion 231 is disposed in a portion of the side surface and the upper surface of the protrusion 231, it is possible to prevent the light emitted from the light source 240 from reaching the diffuser plate 280 while being concentrated in a partial area, thereby reducing the brightness deviation between the area where the light source 240 is disposed (having more light) and the area between the light sources 240 (having less light).

[0134] Reference Figure 7 Among the light emitted from the light source 240 , there may be light L2 (hereinafter, referred to as second light) that is emitted to the side and then exits to the outside of the protrusion 231 through at least one opening 431 , 432 , 433 , and 434 .

[0135] The second light L2 may be reflected, scattered, or diffracted to the diffusion plate 280 by the upper portion 335 or the support portion 336 of another adjacent protrusion 231 , or may be reflected, scattered, or diffracted to the diffusion plate 280 by the vertical portion 232 of the reflector 230 .

[0136] Therefore, since the plurality of protrusions 231 provided in the reflector 230 are provided to overlap with the light source 240 , it is possible to prevent light emitted from the light source from being concentrated in a partial area, thereby preventing visual perception such as moire fringes.

[0137] Therefore, light emitted from the light source 240 may be uniformly distributed toward the diffusion plate 280 without being confined in the protrusion 231 .

[0138] like Figure 7 As shown, the plurality of protrusions 231 may have different sizes.

[0139] For example, Figure 4 and Figure 7 As shown in FIG, the sizes of the first opening 431 and the second opening 432 may be smaller than the sizes of the third opening 433 and the fourth opening 434 .

[0140] The first opening 431 and the second opening 432 facing each other may have respective sizes corresponding to each other. The third opening 433 and the fourth opening 434 may also have respective sizes corresponding to each other.

[0141] The first to fourth openings 431 , 432 , 433 , and 434 may have heights H1 corresponding to each other.

[0142] The maximum widths W1 of the first and second openings 431 and 432 may correspond to each other. The maximum widths W2 of the third and fourth openings 433 and 434 may correspond to each other. The maximum widths W1 of the first and second openings 431 and 432 may be smaller than the maximum widths W2 of the third and fourth openings 433 and 434.

[0143] The sizes of the first to fourth openings 431 , 432 , 433 , and 434 may mean areas.

[0144] The maximum widths W1 and W2 of the first to fourth openings 431 , 432 , 433 , and 434 mean the maximum lengths of the first to fourth openings 431 , 432 , 433 , 434 in a direction perpendicular to the direction in which the color conversion sheet 281 is stacked on the diffusion plate 280 .

[0145] like Figure 7As shown, at least one light source 240 may be disposed in the protrusion 231. The first and second openings 431 and 432 may correspond to the first and second side surfaces of the light source 240, and the third and fourth openings 433 and 434 may correspond to the third and fourth side surfaces of the light source 240.

[0146] Widths of the first and second side surfaces of the light source 240 may be smaller than widths of the third and fourth side surfaces of the light source 240 .

[0147] The size of the plurality of openings 337 provided in the protrusion 231 may be adjusted according to the size of the side surface of the light source 240 corresponding to each of the plurality of openings 337 .

[0148] Refer to the following Figure 8 The arrangement relationship between the light source 240 and the protrusion 231 is described in detail.

[0149] Figure 8 is a diagram illustrating an arrangement structure of a reflector and a light source included in a backlight unit according to an embodiment of the present disclosure.

[0150] The following description will not be repeated for configurations and effects that are substantially the same as those described above. In the following description, the same reference numerals may be used to denote elements or components that are the same as those described in the above embodiment.

[0151] Reference Figure 8 , the light source 240 and the protrusion 231 may be disposed such that the center of the light source 240 and the center of the protrusion 231 correspond to each other.

[0152] The light source 240 may be disposed to be spaced apart from the support portion 336 of the protrusion 231. That is, the light source 240 and the protrusion 231 do not contact each other.

[0153] For example, one side surface of the light source 240 may be spaced apart from the support portion 336 of the protrusion 231 by an interval X of 1 mm to 6 mm.

[0154] When one side surface of the light source 240 and the support portion 336 of the protrusion 231 are spaced less than 1 mm apart, the support portion 336 of the protrusion 231 and the light source 240 may contact each other due to a process error during manufacturing of the backlight unit, thereby damaging the light source 240 .

[0155] When one side surface of the light source 240 and the supporting portion 336 of the protrusion 231 are spaced apart by more than 6 mm, the distance between the light sources 240 increases, thereby reducing brightness uniformity and the brightness of the backlight unit.

[0156] Figure 9 and Figure 10is a diagram illustrating another structure of a protrusion of a reflector according to an embodiment of the present disclosure. Figure 11 It shows Figure 10 A side view of the protruding structure of the reflector.

[0157] The following description will not be repeated for configurations and effects that are substantially the same as those described above. In the following description, the same reference numerals may be used to denote elements or components that are the same as those described in the above embodiment.

[0158] Reference Figures 9 to 11 , the reflector 230 included in the backlight unit according to the embodiment of the present disclosure may include a protrusion 231 .

[0159] The protrusion 231 may include at least one hole 935 and 936 provided in the upper portion 335 of the protrusion 231 .

[0160] For example, the upper portion 335 of the protrusion 231 may include: at least one second hole 935, which is located in the center of the upper portion 335 of the protrusion 231 and surrounds the center; and at least one third hole 936, which is located farther away from the center of the upper portion 335 of the protrusion 231 than the second hole 925.

[0161] like Figure 9 As shown, the plurality of third holes 936 may be disposed around the plurality of second holes 935 .

[0162] When the plurality of holes 935 and 936 are located in the upper portion 335 of the protrusion 231 , at least two of the holes may have different diameters.

[0163] For example, the diameter of the second hole 935 may be smaller than the diameter of the third hole 936 .

[0164] The area where the intensity of light emitted from the light source 240 is strongest may correspond to the center of the upper portion 335 of the protrusion 231. Since the second hole 935 located at the center of the upper portion 335 of the protrusion 231 is formed to have a larger diameter than the third hole 936, the brightness deviation from the area with a relatively small amount of light can be reduced.

[0165] However, the shapes of the second hole 935 and the third hole 936 according to an embodiment of the present disclosure are not limited thereto, and the diameter of the second hole 935 and the diameter of the third hole 936 may correspond to each other.

[0166] The diameter of the second hole 935 may be 0.3 mm to 1 mm. The diameter of the third hole 936 may be 0.5 mm to 1 mm.

[0167] When the diameter of the holes 935 and 936 provided in the upper portion 335 of the protrusion 231 is less than 0.3 mm, the holes 935 and 936 may be difficult to form and may not sufficiently transmit the light emitted from the light source 240 .

[0168] When the diameter of the holes 935 and 936 provided in the upper portion 335 of the protrusion 231 exceeds 1 mm, the amount of light passing through the holes 935 and 936 increases, so that the light amount may be concentrated in the area corresponding to the upper portion 335 of the protrusion 231, resulting in uneven brightness.

[0169] The support portions 336 of the protrusion 231 according to an embodiment of the present disclosure may be configured such that two pairs of support portions 336 are disposed to face each other.

[0170] like Figure 9 As shown, in a plan view, a plurality of support portions 336 of the protrusion 231 may be respectively provided on the top, bottom, left, and right sides around the center of the upper portion 335 of the protrusion 231 .

[0171] like Figure 10 As shown, in a plan view, the plurality of support portions 336 of the protrusion 231 may be disposed in directions other than the 0°, 90°, 180°, and 270° directions relative to the upper portion 335 of the protrusion 231 .

[0172] Reference Figure 11 , the upper portion 335 of the protrusion 231 may be shaped to be concave toward the light source 240 .

[0173] A portion of the light emitted from the light source 240 (light that fails to exit through the hole in the upper portion of the protrusion among the light directed toward the upper portion of the protrusion) can reach the recessed portion 335 of the upper portion 335 of the protrusion 231 and be scattered, reflected, diffracted or transmitted, and then be changed in path to the outside of the protrusion 231 through an opening provided in the side surface of the protrusion 231.

[0174] The light emitted to the outside of the protrusion 231 may reach the diffusion plate 280 after changing its path by the bottom portion 310 of the reflector 230, or the first light L1 may reach the diffusion plate 280 after changing its path by the vertical portion 232 of the reflector 230. Alternatively, the first light L1 may change its path by the support portion 336 or the upper portion 335 of another protrusion 231 adjacent thereto and then reach the diffusion plate 280.

[0175] Therefore, it is possible to prevent image quality from being deteriorated due to brightness non-uniformity in a region corresponding to the upper surface of the light source 240 .

[0176] The above-mentioned embodiment will be briefly described below.

[0177] The backlight unit according to an embodiment of the present disclosure may include: at least one light source 240 provided on a printed circuit 220 and spaced apart from each other; a reflector 230 provided on the printed circuit 220 and including at least one protrusion 231 provided to correspond to the at least one light source 240; and a diffusion plate 280 provided on the reflector 230. The at least one protrusion 231 may respectively surround the at least one light source 240. The protrusion 231 may include at least one opening 337 in a side surface thereof.

[0178] A height H1 of the opening 337 is lower than a height H2 of the entire protrusion 231 .

[0179] To improve light efficiency, the heights of at least two openings 337 may be different from each other. A minimum length from the bottom 310 of the reflector 230 to the upper portion 335 of the protrusion 231 may be different from region to region.

[0180] For example, the minimum length of the protrusion 231 from the bottom 310 of the reflector 230 to the center of the protrusion 231 may be smaller than the minimum length from the bottom 310 of the reflector 230 to the right area of ​​the protrusion 231 (eg, Figure 11 The minimum length of the protrusion 231 in the right area of ​​the protrusion 231).

[0181] In addition, the area from the bottom 310 of the reflector 230 to the right side of the protrusion 231 (eg, Figure 11 The minimum length of the protrusion 231 in the right area of ​​the protrusion 231 may be smaller than the minimum length from the bottom 310 of the reflector 230 to the left area of ​​the protrusion 231 (eg, Figure 11 The minimum length of the protrusion 231 in the left area of ​​the protrusion 231).

[0182] In other words, the height of the central portion of the protrusion 231 may be lower than the height of one side of the protrusion 231 , and the height of one side of the protrusion 231 may be lower than the height of the other side of the protrusion 231 .

[0183] Therefore, the height of the protrusion 231 may be formed to be different from region to region to improve light efficiency.

[0184] The protrusion 231 may include a plurality of openings 337 , a support portion 336 disposed between the plurality of openings 337 , and an upper portion integrally formed with an end portion of the support portion 336 .

[0185] A portion of the upper portion 335 of the protrusion 231 may extend up to a portion of a side surface of the protrusion 231 .

[0186] The upper portion 335 of the protrusion 231 may include at least one hole 935 and 936 .

[0187] The upper portion 335 of the protrusion 231 may include at least one second hole 935 and at least one third hole 936 having diameters different from each other.

[0188] The second hole 935 may have a smaller diameter than the third hole 936. The second hole 935 may be disposed in and around the center of the upper portion 335. The third hole 936 may be disposed farther from the center of the upper portion 335 than the second hole 935.

[0189] The upper portion 335 of the protrusion 231 may be shaped to be concave toward the light source 240 .

[0190] The support portion 336 may be disposed to be spaced apart from the light source 240 .

[0191] The reflector 230 may include a bottom portion 310. The bottom portion 310 may include at least one first hole 610. The light source 240 may be disposed to correspond to the first hole 610.

[0192] The backlight unit may further include a bottom cover 210 disposed under the printed circuit 220 and including an extension in a lateral direction of the printed circuit 220. The reflector 230 may include a vertical portion 232 extending from the bottom 310 and disposed on a side surface of the extension of the bottom cover 210.

[0193] The at least one opening 337 of the reflector may include a first opening 431 , a second opening 432 facing the first opening 431 , a third opening 433 disposed between the first and second openings 431 and 432 , and a fourth opening 434 disposed between the first and second openings 431 and 432 and facing the third opening 433 .

[0194] The size of the first opening 431 may correspond to the size of the second opening 432 , and the size of the third opening 433 may correspond to the size of the fourth opening 434 .

[0195] The maximum width W1 of the first opening 431 and the second opening 432 may be smaller than the maximum width W2 of the third opening 433 and the fourth opening 434 .

[0196] The width of the side surface of the light source 240 positioned corresponding to the first opening 431 and the second opening 432 may be smaller than the width of the side surface of the light source 240 positioned corresponding to the third opening 433 and the fourth opening 434 .

[0197] The center position of the light source 240 may correspond to the center position of the protrusion 231. Therefore, the light source 240 and the support portion 336 of the protrusion 231 may be prevented from contacting each other.

[0198] A surface of the protrusion 231 may have a round shape.

[0199] A display device according to an embodiment of the present disclosure may include: at least one light source 240 disposed on a printed circuit 220 and spaced apart from each other; a reflector 230 disposed on the printed circuit 220 and including at least one protrusion 231 disposed corresponding to the at least one light source 240; a diffusion plate 280 disposed on the reflector; a color conversion film 281 disposed on the diffusion plate 280; and a display panel 110 disposed on the color conversion film 281. The at least one protrusion 231 may respectively surround the at least one light source 240. The protrusion 231 may include at least one opening 337 in a side surface thereof.

[0200] According to an embodiment of the present disclosure, a backlight unit that provides light to a display panel and a display device including the backlight unit can be provided, which can enhance the image quality of the backlight unit while reducing the thickness by allowing a reflector to include at least one protrusion and allowing the protrusion to have at least one opening.

[0201] The above description has been given to enable any person skilled in the art to make and use the technical ideas of the present disclosure, and the above description has been provided in the context of a specific application and its requirements. Various modifications, additions and substitutions to the described embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the present disclosure. The above description and accompanying drawings provide examples of the technical ideas of the present disclosure for illustrative purposes only. That is, the disclosed embodiments are intended to illustrate the scope of the technical ideas of the present disclosure. Therefore, the scope of the present disclosure is not limited to the embodiments shown, but should be given the widest scope consistent with the claims. The scope of protection of the present disclosure should be interpreted based on the appended claims, and all technical concepts within their equivalent scope should be interpreted as being included within the scope of the present disclosure.

Claims

1. A backlight unit comprising: printed circuits; at least one light source disposed on the printed circuit and spaced apart from one another; a reflector disposed on the printed circuit and comprising at least one protrusion disposed to correspond to the at least one light source; a diffusion plate, disposed on the reflector; as well as a bottom cover disposed below the printed circuit and including an extension in a lateral direction of the printed circuit, wherein the at least one protrusion surrounds the at least one light source respectively, wherein the protrusion comprises at least one opening in a side surface of the protrusion, wherein the reflector includes a bottom, and the reflector includes a vertical portion extending from the bottom and disposed on a side surface of the extension portion of the bottom cover, and Wherein, an upper portion of the protrusion is shaped to be concave toward the light source.

2. The backlight unit according to claim 1, wherein The height of the opening is lower than the height of the entire protrusion.

3. The backlight unit according to claim 1, wherein The protrusion comprises: multiple openings; a support portion disposed between the plurality of openings; and The upper portion of the protrusion is formed integrally with the end portion of the support portion.

4. The backlight unit according to claim 3, wherein: A portion of the upper portion of the protrusion extends up to a portion of a side surface of the protrusion.

5. The backlight unit according to claim 4, wherein The upper portion of the protrusion includes at least one hole. The backlight unit according to claim 5 , wherein: The upper portion of the protrusion includes at least one first hole and at least one second hole having different diameters.

7. The backlight unit according to claim 6, wherein The diameter of the first hole is smaller than the diameter of the second hole, wherein the first hole is provided in the center of the upper portion and surrounds the center, and Wherein, the second hole is arranged farther away from the center of the upper portion than the first hole.

8. The backlight unit according to claim 3, wherein The support portion is provided to be spaced apart from the light source.

9. The backlight unit according to claim 1, in, The bottom comprises at least one hole, and Wherein, the light source is arranged to correspond to the hole in the bottom.

10. The backlight unit according to claim 1, wherein The at least one opening of the protrusion of the reflector includes a first opening, a second opening facing the first opening, a third opening disposed between the first opening and the second opening, and a fourth opening disposed between the first opening and the second opening and facing the third opening. The backlight unit according to claim 10 , wherein: A size of the first opening corresponds to a size of the second opening, and a size of the third opening corresponds to a size of the fourth opening.

12. The backlight unit according to claim 11, wherein The maximum widths of the first opening and the second opening are smaller than the maximum widths of the third opening and the fourth opening.

13. The backlight unit according to claim 12, wherein: A width of a side surface of the light source positioned corresponding to the first opening and the second opening is smaller than a width of a side surface of the light source positioned corresponding to the third opening and the fourth opening.

14. The backlight unit according to claim 1, wherein The center position of the light source corresponds to the center position of the protrusion.

15. The backlight unit according to claim 1, wherein The surface of the protrusion has a rounded shape.

16. The backlight unit according to claim 1, wherein A height of a central portion of the protrusion is lower than a height of one side of the protrusion, and a height of the one side of the protrusion is lower than a height of the other side of the protrusion.

17. The backlight unit according to claim 8, wherein An interval between the support portion and a side surface of the light source is in a range of 1 mm to 6 mm.

18. The backlight unit according to claim 6, wherein The diameter of the first hole is in the range of 0.3 mm to 1 mm, and the diameter of the second hole is in the range of 0.5 mm to 1 mm.

19. A backlight unit comprising: printed circuits; at least one light source disposed on the printed circuit and spaced apart from one another; a reflector disposed on the printed circuit and comprising at least one protrusion, wherein the at least one light source is respectively disposed inside the at least one protrusion and does not contact the at least one protrusion; a diffusion plate, disposed on the reflector; as well as a bottom cover disposed below the printed circuit and including an extension in a lateral direction of the printed circuit, wherein the protrusion includes at least one opening in a side surface of the protrusion, and a shape of the protrusion is determined according to a shape of the light source, wherein the reflector includes a bottom, and the reflector includes a vertical portion extending from the bottom and disposed on a side surface of the extension portion of the bottom cover, and Wherein, an upper portion of the protrusion is shaped to be concave toward the light source.

20. A display device comprising the backlight unit according to any one of claims 1 to 19.

21. A display device comprising: printed circuits; at least one light source disposed on the printed circuit and spaced apart from one another; a reflector disposed on the printed circuit and comprising at least one protrusion disposed to correspond to the at least one light source; a diffusion plate, disposed on the reflector; A color conversion film is provided on the diffusion plate; a display panel, disposed on the color conversion film; as well as a bottom cover disposed below the printed circuit and including an extension in a lateral direction of the printed circuit, wherein the at least one protrusion surrounds the at least one light source respectively, wherein the protrusion comprises at least one opening in a side surface of the protrusion, wherein the reflector includes a bottom, and the reflector includes a vertical portion extending from the bottom and disposed on a side surface of the extension portion of the bottom cover, and Wherein, an upper portion of the protrusion is shaped to be concave toward the light source.

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