Light guide film, backlight unit, and display device

Abstract

The invention provides a light guide film, a backlight unit and a display device. A light guide portion is disposed in a hole of a reflective plate on which a light source is disposed, and a light guide film is disposed directly on the reflective plate and the light guide portion to provide a light guide function and a light shielding function. Accordingly, a method is provided that facilitates implementation of a backlight unit having a small thickness satisfying image quality. Further, each of the light shielding patterns has a different reflectivity in a different region, thereby increasing the amount of light supplied to the region between the light sources. Accordingly, a backlight unit having a reduced number of light sources and improved image quality may be provided.

Description

[0001] This application is a divisional application of the application with national application number 202010542092.1, application date June 15, 2020, and invention name “Light guide film, backlight unit and display device”.

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS

[0003] This application claims priority to Korean Patent Application No. 10-2019-0073950, filed on June 21, 2019, and Korean Patent Application No. 10-2020-0051452, filed on April 28, 2020, which are hereby incorporated by reference for all purposes as if fully set forth herein. Technical Field

[0004] Embodiments of the present disclosure relate to a light guide film, a backlight unit, and a display device. Background Art

[0005] As the information society develops, the demand for display devices that display images is increasing. In this regard, various types of display devices such as liquid crystal display (LCD) devices and organic light emitting diode (OLED) display devices have been widely used.

[0006] Among these display devices, an LCD device may include a display panel and an optical device, such as a backlight unit, that supplies light to the display panel.

[0007] Therefore, the display device may be thick due to the backlight unit. If the thickness of the backlight unit is reduced, a sufficient optical gap between the light source and the display panel cannot be ensured, thereby reducing image quality. Summary of the invention

[0008] Embodiments of the present disclosure provide a backlight unit having a reduced thickness satisfying image quality and a display device including the same.

[0009] Embodiments of the present disclosure provide a method that helps realize a backlight unit having a small thickness that satisfies image quality.

[0010] According to one aspect, an embodiment of the present disclosure provides a display device including a display panel and a backlight unit supplying light to the display panel.

[0011] The backlight unit may include: a plurality of light sources arranged on a printed circuit; a reflective plate, which is arranged on the printed circuit and includes a plurality of holes, in which the plurality of light sources are respectively arranged; a plurality of light guide portions which are respectively arranged in the plurality of holes to surround the plurality of light sources; and a light guide film, which is arranged on the reflective plate and the plurality of light guide portions and includes at least one light guide layer and a plurality of light shading patterns which are positioned on the top surface of the light guide layer corresponding to the plurality of light sources, respectively.

[0012] In addition, the light guide film may further include a coating layer protecting the light shielding pattern, the coating layer being disposed on a top surface of the light guide layer on which the light shielding pattern is disposed and having a flat top surface.

[0013] Here, a top surface of each of the plurality of light guide portions may be convex, and at least a portion of the top surface of the light guide portion may be positioned higher than a top surface of the reflective plate.

[0014] Alternatively, the top surfaces of the plurality of light guides may be positioned on the same plane as the top surface of the reflective plate.

[0015] According to another aspect, an embodiment of the present disclosure provides a light-guiding film, which includes: a first light-guiding layer, which includes a plurality of recessed portions on one surface, and another surface opposite to the one surface is flat; a second light-guiding layer, which contacts the other surface of the first light-guiding layer and has two flat surfaces; and a plurality of light-shielding patterns, which are arranged on the surface of the second light-guiding layer other than the surface of the second light-guiding layer in contact with the first light-guiding layer.

[0016] Here, a plurality of light shielding patterns may be respectively disposed at positions corresponding to the plurality of concave portions.

[0017] Alternatively, each of the plurality of light shielding patterns may include: a first portion having a first reflectivity; and a second portion disposed outside the first portion and having a second reflectivity smaller than the first reflectivity. Here, the first portion may be disposed at a position corresponding to the concave portion, and at least a portion of the second portion may be disposed at a position corresponding to a position around the concave portion.

[0018] According to an embodiment of the present disclosure, the light source and the light guide are disposed in a hole formed in the reflective plate, and the light guide film including the light shielding pattern is disposed on the reflective plate and the light guide. Therefore, the thickness of the backlight unit is reduced and the image quality can be maintained.

[0019] According to an embodiment of the present disclosure, a light guide film having a light guide function and a light shielding function is provided to be attached to a light guide portion and a reflective plate. Therefore, a backlight unit having a reduced thickness can be easily realized.

[0020] According to one aspect of the present disclosure, a display device is provided, comprising: a display panel; and a backlight unit for supplying light to the display panel, wherein the backlight unit comprises: a plurality of light sources arranged on a printed circuit; a reflective plate, the reflective plate being arranged on the printed circuit and comprising a plurality of holes, in which the plurality of light sources are respectively arranged; a plurality of light guide portions, the plurality of light guide portions being respectively arranged in the plurality of holes to surround the plurality of light sources; and a light guide film, the light guide film being arranged on the reflective plate and the plurality of light guide portions, and comprising a first light guide layer, a second light guide layer arranged on the first light guide layer, and a plurality of light shielding patterns, the plurality of light shielding patterns being located on the second light guide layer and positioned correspondingly to the plurality of light sources, respectively, wherein a top surface of the second light guide layer comprises a plurality of portions, each of the plurality of portions having a plurality of protrusions, wherein each of the plurality of light shielding patterns is positioned in each of the plurality of portions of the second light guide layer, so that each of the light shielding patterns has a flat top surface and a bottom surface having a plurality of protrusions, wherein a bottom surface of the first light guide layer comprises a plurality of recessed portions, wherein each of the plurality of light shielding patterns is positioned correspondingly to the plurality of recessed portions, respectively.

[0021] According to another aspect of the present disclosure, a backlight unit is provided, comprising: a plurality of light sources arranged on a printed circuit; a reflective plate, the reflective plate being arranged on the printed circuit and comprising a plurality of holes, in which the plurality of light sources are respectively arranged; a plurality of light guide portions, the plurality of light guide portions being respectively arranged in the plurality of holes to surround the plurality of light sources; and a light guide film, the light guide film being arranged on the reflective plate and the plurality of light guide portions, and comprising a first light guide layer, a second light guide layer arranged on the first light guide layer, and a plurality of light shielding patterns, the plurality of light shielding patterns being arranged on the second light guide layer and positioned corresponding to the plurality of light sources, respectively, wherein a top surface of the second light guide layer comprises a plurality of portions, each of the plurality of portions having a plurality of protrusions, wherein each of the plurality of light shielding patterns is positioned in each of the plurality of portions of the second light guide layer so that each light shielding pattern has a flat top surface and a bottom surface having a plurality of protrusions, wherein a bottom surface of the first light guide layer comprises a plurality of recessed portions, wherein the first light guide layer has an adhesion function, and the first light guide layer directly contacts the bottom surface of the second light guide layer and the corresponding top surfaces of the reflective plate and the plurality of light guide portions through the adhesion function.

[0022] According to another aspect of the present disclosure, a light-guiding film is provided, comprising: a first light-guiding layer, the first light-guiding layer having a first surface including a plurality of recessed portions thereon, and a second surface which is flat and opposite to the first surface; a second light-guiding layer, the second light-guiding layer having a third surface which contacts the second surface of the first light-guiding layer and has a flat surface, and a fourth surface opposite to the third surface; and a plurality of light-shielding patterns, wherein the fourth surface of the second light-guiding layer comprises a plurality of parts, each of the plurality of parts having a plurality of protrusions, wherein each of the plurality of light-shielding patterns is positioned in each of the plurality of parts of the second light-guiding layer so that each of the light-shielding patterns has a flat top surface and a bottom surface having a plurality of protrusions, wherein a size of a protrusion among the plurality of protrusions located in a central area of ​​each part is larger than a size of a protrusion located in an edge area of ​​each part. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The above and other objects, features and advantages of the present disclosure will be more clearly understood from the following detailed description in conjunction with the accompanying drawings, in which:

[0024] Figure 1 is a schematic diagram showing a configuration of a display device according to an embodiment of the present disclosure;

[0025] Figure 2 is a diagram showing an exemplary cross-sectional structure of a backlight unit according to an embodiment of the present disclosure;

[0026] Figure 3 is a diagram showing another exemplary cross-sectional structure of a backlight unit according to an embodiment of the present disclosure;

[0027] Figure 4 It shows the manufacturing Figure 3 A diagram of an exemplary process of a backlight unit is shown;

[0028] Figure 5 It is shown that the Figure 3 FIG. 1 is a diagram showing an exemplary structure of a light guide film in a backlight unit;

[0029] Figure 6 It shows that the setting Figure 5 FIG. 1 is a diagram showing an exemplary structure of a light shielding pattern on a light guide film;

[0030] Figure 7 It shows that the setting Figure 5 A diagram of another exemplary structure of a light-shielding pattern on a light-guiding film shown;

[0031] Fig. 8A , Figure 8B and Figure 8C It is shown Figure 7 FIG. 1 is a diagram showing an example of a specific implementation of the structure of the shading pattern shown;

[0032] Fig. 9 is a diagram showing another exemplary cross-sectional structure of a backlight unit according to an embodiment of the present disclosure;

[0033] Fig.10 , Fig.11 and Fig.12 is a diagram showing other exemplary cross-sectional structures of a backlight unit according to an embodiment of the present disclosure; and

[0034] Fig.13 is a table listing test results of the performance of each backlight unit structure according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0035] In the following description of examples or embodiments of the present invention, 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 components, even when these components are shown in different drawings from each other. In addition, in the following description of examples or embodiments of the present invention, when it is determined that the detailed description of known functions and components incorporated herein may make the subject matter of some embodiments of the present invention particularly unclear, the description will be omitted. Terms such as "including", "having", "comprising", "consisting of", and "formed by" used herein are generally intended to allow the addition of other components unless these terms are used together with the term "only". As used herein, the singular form is intended to include the plural form unless the context clearly indicates otherwise.

[0036] Terms such as "first", "second", "A", "B", "(A)" or "(B)" may be used herein to describe elements of the present invention. Each of these terms is not used to limit the nature, sequence, order or number of elements, etc., but is only used to distinguish the corresponding element from other elements.

[0037] When it is mentioned that a first element is “connected or coupled”, “contacted or overlapped”, etc. with a second element, it should be interpreted that the first element can not only be “directly connected or coupled”, “directly contacted or overlapped” with the second element, but also a third element can be “interposed” between the first element and the second element, or the first element and the second element can be “connected or coupled”, “contacted or overlapped”, etc. with each other via a fourth element. Here, the second element can be included in at least one of the two or more elements that are “connected or coupled”, “contacted or overlapped”, etc. with each other.

[0038] When time relationship terms such as "after", "subsequently", "next", "before", etc. are used to describe the processing or operation of an element or configuration, or the process or steps in an operation, process, or manufacturing method, unless the terms "directly" or "immediately" are used together, these terms can be used to describe non-continuous or non-sequential processing or operations.

[0039] In addition, when referring to any dimension, relative size, etc., it should be considered that the numerical value or corresponding information (e.g., level, range, etc.) of the element or feature includes tolerances or error ranges that may be caused by various factors (e.g., processing factors, internal or external influences, noise, etc.), even when the relevant description is not specifically stated. In addition, the term "may" fully encompasses all meanings of the term "can".

[0040] Figure 1 is a schematic diagram showing a configuration of a display device 100 according to an embodiment of the present disclosure.

[0041] Reference Figure 1 According to an embodiment of the present disclosure, a display device 100 may include: a display panel 110 including an active area A / A and a non-active area N / A; a gate driver circuit 120; a data driver circuit 130; and a controller 140 for driving the display panel 110.

[0042] In the display panel 110 , a plurality of gate lines GL and a plurality of data lines DL may be disposed, and a plurality of sub-pixels SP may be disposed at intersections between the gate lines GL and the data lines DL.

[0043] The gate driver circuit 120 may be controlled by the controller 140 , and control driving timing of a plurality of sub-pixels SP by sequentially outputting scan signals to a plurality of gate lines GL disposed in the display panel 110 .

[0044] The gate driver circuit 120 may include one or more gate driver integrated circuits (GDICs) and may be located on one side or both sides of the display panel 110 according to a driving scheme.

[0045] Each GDIC may be coupled to a bonding pad of the display panel 110 through tape automated bonding (TAB) or chip on glass (COG), or may be configured as a gate in panel (GIP) type and directly disposed in the display panel 110. When necessary, each GDIC may be integrated in the display panel 110. In addition, each GDIC may be mounted on a film coupled to the display panel 110 through a chip on film (COF).

[0046] The data driver circuit 130 may receive the image data DATA from the controller 140 and convert the image data into an analog data voltage. In addition, the data driver circuit 130 may output a data voltage to each data line DL at a timing when a scan signal is applied through the gate line GL so that the sub-pixel SP exhibits a light emission intensity corresponding to the image data.

[0047] The data driver circuit 130 may include one or more source driver integrated circuits (SDICs).

[0048] Each SDIC may include a shift register, a latch circuit, a digital-to-analog converter, an output buffer, and the like.

[0049] Each SDIC may be coupled to a bonding pad of the display panel 110 by TAB or COG, or may be directly provided in the display panel 110. When necessary, each SDIC may be integrated in the display panel 110. In addition, each SDIC may be implemented by COF. In this case, the SDIC may be mounted on a film coupled to the display panel 110 and electrically coupled to the display panel 110 by wiring on the film.

[0050] The controller 140 may apply various control signals to the gate driver circuit 120 and the data driver circuit 130 to control operations of the gate driver circuit 120 and the data driver circuit 130 .

[0051] The controller 140 may be mounted on a printed circuit board (PCB), a flexible printed circuit, or the like, and electrically coupled to the gate driver circuit 120 and the data driver circuit 130 through the PCB, the flexible printed circuit, or the like.

[0052] The controller 140 may control the gate driver circuit 120 to output a scan signal at a timing defined by each frame. The controller 140 may convert image data received from an external source into a data signal format used in the data driver circuit 130 and output the converted image data to the data driver circuit 130.

[0053] In addition to image data, the controller 140 may receive various timing signals from an external source (eg, a host system). The timing signals may include a vertical synchronization signal VSYNC, a horizontal synchronization signal HSYNC, an input data enable signal DE, a clock signal CLK, and the like.

[0054] The controller 140 may generate various control signals using various timing signals received from an external source and output the control signals to the gate driver circuit 120 and the data driver circuit 130 .

[0055] For example, the controller 140 may output various gate control signals GCS for controlling the gate driver circuit 120 , wherein the various gate control signals GCS include a gate start pulse GSP, a gate shift clock signal GSC, a gate output enable signal GOE, and the like.

[0056] The gate start pulse GSP may control the operation start timing of one or more GDICs of the gate driver circuit 120. The gate shift clock signal GSC may be a clock signal commonly input to one or more GDICs to control the shift timing of the scan signal. The gate output enable signal GOE may specify the timing information of one or more GDICs.

[0057] In addition, the controller 140 may output various data control signals DCS for controlling the data driver circuit 130 , including a source start pulse SSP, a source sampling clock signal SSC, a source output enable signal SOE, and the like.

[0058] The source start pulse SSP may control the data sampling start timing of one or more SDICs of the data driver circuit 130. The source sampling clock signal SSC may be a clock signal controlling the data sampling timing of each of the SDICs. The source output enable signal SOE may control the output timing of the data driver circuit 130.

[0059] The display device 100 may further include a power management integrated circuit (PMIC) that applies various types of voltages or currents to the display panel 110, the gate driver circuit 120, the data driver circuit 130, etc., or controls various types of voltages or currents to be applied to the display panel 110, the gate driver circuit 120, the data driver circuit 130, etc.

[0060] Each sub-pixel SP may be a region defined by an intersection between a gate line GL and a data line DL, in which a liquid crystal or a light emitting element may be disposed according to the type of the display device 100 .

[0061] For example, when the display device 100 is an LCD device, the display device 100 may include an optical device such as a backlight unit that irradiates light onto the display panel 110, and liquid crystals may be provided in the sub-pixels SP of the display panel 110. The orientation of the liquid crystals may be adjusted by an electric field generated by applying a data voltage to each sub-pixel SP, so that an image may be displayed by presenting a light emission intensity corresponding to image data.

[0062] Therefore, the backlight unit may increase the thickness of the display device 100 .

[0063] Embodiments of the present disclosure provide a backlight unit with a reduced thickness that can maintain image quality, and a method of facilitating implementation of the backlight unit with a reduced thickness.

[0064] Figure 2 is a diagram illustrating an exemplary cross-sectional structure of a backlight unit according to an embodiment of the present disclosure.

[0065] Reference Figure 2 A backlight unit may be disposed under the display panel 110 , and include a plurality of optical members for supplying light to the display panel 110 .

[0066] For example, the backlight unit may include a plurality of light sources 240 disposed on a printed circuit 230. The printed circuit 230 may be disposed to be attached to the board 210 through the first adhesive layer 220. According to the type of the display device 100, the board 210 may be a cover back.

[0067] Each of the light sources 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. The light source 240 may emit light in a white wavelength band, and in some cases emit light in a specific wavelength band. For example, the light source 240 may emit light in a blue wavelength band and excite the light through an optical member disposed on the light source 240 to supply the light in the white wavelength band to the display panel 110 (for example, a portion of the emitted blue light is converted into light of other specific wavelength bands (for example, a yellow wavelength band) through an optical member, and the light obtained by the conversion is combined with the emitted blue light to obtain white light).

[0068] A reflective plate 260 may be provided on the printed circuit 230. The reflective plate 260 may be provided to be attached to the printed circuit 230 through the second adhesive layer 250. The reflective plate 260 may include a plurality of holes H, and the light sources 240 may be provided in the holes H included in the reflective plate 260. That is, the reflective plate 260 having a reflective function may be provided in at least a portion of an area on the printed circuit 230 where the light sources 240 are not provided.

[0069] The top surface of the reflective plate 260 may be positioned higher than the top end of the light source 240 disposed in the hole H. The light guide part 270 may be disposed in the hole H of the reflective plate 260. That is, a plurality of light guide parts 270 may be disposed in each hole H.

[0070] The light guide 270 may be formed of, for example, resin. In addition, the light guide 270 may be disposed to surround the light source 240 in the hole H of the reflective plate 260. That is, the light guide 270 may be disposed to fill a space other than the space occupied by the light source 240 in the hole H of the reflective plate 260.

[0071] In this way, the light guide part 270 may be disposed to directly contact the light source 240 and guide the light emitted from the light source 240 to diffuse upward.

[0072] The top surface of the light guide part 270 may be flat and located on the same plane as the top surface of the reflective plate 260 .

[0073] The light guide film 300 may be disposed on the light guide part 270 and the reflective plate 260 .

[0074] The light guide film 300 may include at least one light guide layer 310 and an optical pattern disposed on the light guide layer 310 .

[0075] For example, the light guide film 300 may include: a first light guide layer 310a, which is disposed on the reflective plate 260 and the light guide portion 270 and has a flat top surface; a second light guide layer 310b, which is disposed on the first light guide layer 310a; and a plurality of light shielding patterns 320, which are disposed on the second light guide layer 310b.

[0076] The first light guide layer 310a may be, for example, a silicon-based adhesive layer, and may be disposed in direct contact with the top surface of the reflective plate 260 and the top surface of the light guide portion 270. Therefore, the light guide film 300 may be easily disposed on the reflective plate 260 and the light guide portion 270, and provide a function of guiding light emitted through the light guide portion 270.

[0077] The second light guide layer 310b may be formed of, for example, polycarbonate (PC) or polyethylene terephthalate (PET), and provide a light guide function together with the first light guide layer 310a. That is, the first light guide layer 310a and the second light guide layer 310b may be disposed on the light guide portion 270 to uniformly diffuse the light emitted from the light source 240 to the display panel 110.

[0078] The first light guide layer 310a and the second light guide layer 310b are only examples, and the light guide film 300 may include only one light guide layer 310 or a plurality of light guide layers 310. Furthermore, in some cases, the first light guide layer 310a disposed under the second light guide layer 310b may be regarded as an adhesive layer disposed separately from the light guide film 300. Furthermore, when necessary, the first light guide layer 310a may be thicker than the second light guide layer 310b, or the second light guide layer 310b may be thicker than the first light guide layer 310a.

[0079] The light shielding pattern 320 may be disposed on the top surface of the second light guide layer 310b. The light shielding pattern 320 may be disposed to correspond to the light source 240 disposed on the printed circuit 230. This may be equivalent to disposing the light shielding pattern 320 to correspond to the hole H of the reflective plate 260.

[0080] The shading pattern 320 can provide a reflection function, a scattering function, and a diffraction function. Since the shading pattern 320 is arranged to correspond to the light source 240, the shading pattern 320 can provide a function of shielding at least a portion of the light vertically emitted from the light source 240. In other words, the shading pattern 320 can reflect at least a portion of the light vertically emitted from the light source 240 toward the reflective plate 260. In addition, the shading pattern 320 can transmit a portion of the light arriving or change the path of the light. Therefore, even if the distance between the light source 240 and the display panel 110 is reduced, a hot spot can be prevented from being generated at a position corresponding to the light source 240.

[0081] A plurality of optical sheets may be disposed on the light guide film 300. For example, a diffusion plate 400, a color conversion sheet 500, a prism sheet 600, and a diffusion sheet 700 may be disposed on the light guide film 300.

[0082] A structure for maintaining the shape of the backlight unit may be provided outside the region where the light source 240 is provided on the printed circuit 230. For example, the dam 800 may be provided along the outer circumference of the printed circuit 230. Alternatively, in some cases, a guide plate or the like may be provided.

[0083] Thus, the light guide film 300 providing the light guide function and the light shielding function can be provided, thereby preventing the thickness of the backlight unit from increasing and maintaining the image quality. In addition, by directly attaching the light guide film 300 to the reflective plate 260 and the light guide portion 270, a small thickness backlight unit can be easily realized.

[0084] In addition, the top surface of the light guide portion 270 may be shaped to be convex, thereby enhancing the light extraction function of the light guide portion 270 and facilitating the arrangement of the light guide film 300 .

[0085] Figure 3 is a diagram illustrating another exemplary cross-sectional structure of a backlight unit according to an embodiment of the present disclosure.

[0086] Reference Figure 3 The backlight unit may include: a plurality of light sources 240 disposed on a printed circuit 230 ; and a reflective plate 260 disposed on the printed circuit 230 and including a plurality of holes H. The light sources 240 may be disposed in the holes H of the reflective plate 260 .

[0087] The light guide portion 270 may be disposed in the hole H of the reflective plate 260 , and the light guide film 300 may be disposed on the light guide portion 270 and the reflective plate 260 .

[0088] The top surface of the light guide part 270 may be shaped to be convex. At least a portion of the top surface of each of the light guide parts 270 may be positioned higher than the top surface of the reflective plate 260.

[0089] That is, in the process of disposing the light guide portion 270 in the hole H of the reflective plate 260, the top surface of the light guide portion 270 may be positioned slightly higher than the top surface of the reflective plate 260. Therefore, the light guide portion 270 may be disposed so that a portion of the light guide portion 270 covers a portion of the top surface of the reflective plate 260.

[0090] The function of extracting light emitted from the light source 240 may be improved by shaping the top surface of the light guide part 270 surrounding the light source 240 in the hole H of the reflective plate 260 to be convex.

[0091] Since the top surface of the light guide portion 270 is convex, the bottom surface of the light guide film 300 disposed on the light guide portion 270 may be shaped concave.

[0092] For example, the light guide film 300 disposed on the reflective plate 260 and the light guide part 270 may include a first light guide layer 310 a , a second light guide layer 310 b , and a light shielding pattern 320 .

[0093] The first light guide layer 310a may be disposed to directly contact the reflective plate 260 and the light guide portion 270, and may include a concave portion 311 in a portion corresponding to the light guide portion 270 having a convex top surface. The top surface of the first light guide layer 310a may be flat, and the top surface of the first light guide layer 310a is opposite to a surface of the first light guide layer 310a on which the concave portion 311 is disposed.

[0094] Therefore, the first light guide layer 310a can provide a light guide function and an adhesion function, and also prevent the formation of a step that may otherwise be caused by the convex shape of the light guide portion 270. Therefore, the light guide film 300 can be disposed more easily.

[0095] Since the first light guide layer 310a should be disposed on the entirety of the reflective plate 260 and the light guide portion 270 , the thickness t of the thickest portion of the first light guide layer 310a may be greater than the vertical distance d between the highest point of each of the light guide portions 270 and the highest point of the reflective plate 260 .

[0096] That is, since the first light guide layer 310a should be disposed on the top surface of the light guide portion 270 for an adhesion function and should have a flat top surface for a flattening function, the thickness of the first light guide layer 310a may be equal to or greater than the difference between the height of the light guide portion 270 and the height of the reflective plate 260.

[0097] The second light guide layer 310 b may be disposed on the first light guide layer 310 a , and the light shielding pattern 320 may be disposed at a position corresponding to the light source 240 on the second light guide layer 310 b .

[0098] In this way, the top surface of the light guide portion 270 may be shaped to be convex to prevent an empty space from being generated between the light guide portion 270 and the light guide film 300 disposed on the light guide portion 270. Therefore, the light guide film 300 providing a light guide function and a light shielding function may be easily disposed, and a light extraction function provided by the light guide portion 270 and the light guide layer of the light guide film 300 may be improved.

[0099] Figure 4 It shows the manufacturing Figure 3 A diagram of an exemplary process of a backlight unit is shown.

[0100] Reference Figure 4 , a light source 240 and a reflective plate 260 including a hole H may be disposed on the printed circuit 230, as shown in FIG. Figure 4 As shown in (1) in FIG. 1 , a metal mask 900 opened at a portion corresponding to the hole H of the reflective plate 260 may be provided on the reflective plate 260 . Subsequently, a material (eg, resin) forming the light guide portion 270 may be provided in the hole H of the reflective plate 260 .

[0101] When the material forming the light guide portion 270 is completely disposed in the hole H of the reflective plate 260, the light guide portion 270 may be formed by curing the material disposed in the hole H of the reflective plate 260. Figure 4 Here, the top surface of the light guide portion 270 may be shaped to be convex.

[0102] When forming the light guide portion 270, the light guide film 300 including the first light guide layer 310a, the second light guide layer 310b and the light shielding pattern 320 may be disposed on the light guide portion 270 and the reflective plate 260. Figure 4 Therefore, the bottom surface of the first light guide layer 310 a disposed in the lower portion of the light guide film 300 may include a concave portion 311 corresponding to the convex shape of the light guide portion 270 .

[0103] As such, the light guide portion 270 may be shaped to be convex, thereby preventing an air gap from being generated between the light guide film 300 and the light guide portion 270 during the process of disposing the light guide film 300 on the light guide portion 270 and the reflective plate 260 .

[0104] Furthermore, by providing both light guiding and light shielding functions by the light guide film 300 including the concave portions 311 formed on the light incident surface and the light shielding patterns 320 provided on the light emitting surface, a backlight unit with a reduced thickness capable of maintaining image quality may be provided.

[0105] Figure 5 It is shown that the Figure 3 FIG. 1 is a diagram showing an exemplary structure of a light guide film 300 in a backlight unit.

[0106] Reference Figure 5 The light guide film 300 may include: a first light guide layer 310a including at least one concave portion 311; a second light guide layer 310b disposed on the first light guide layer 310a; and at least one light shielding pattern 320 disposed on the second light guide layer 310b.

[0107] The first light guide layer 310a may include a concave portion 311 on a bottom surface thereof, and the first light guide layer 310a may be flat on a top surface thereof. The first light guide layer 310a may provide a flattening function to compensate for a step as well as a light guiding function and an adhesion function.

[0108] The second light guide layer 310b may be disposed on the first light guide layer 310a to provide a light guiding function. The second light guide layer 310b may be flat on a top surface thereof, and a light shielding pattern 320 may be disposed on the top surface of the second light guide layer 310b.

[0109] The light shielding pattern 320 may be disposed at a position corresponding to the concave portion 311 disposed on the bottom surface of the first light guide layer 310 a .

[0110] For example, the area S of each of the light shielding patterns 320 may be equal to the area of ​​the entrance of each of the recesses 311. Alternatively, the area S of each of the light shielding patterns 320 may be greater than the area of ​​the entrance of each of the recesses 311 when necessary.

[0111] That is, the concave portion 311 may be formed along the shape of the hole H in which the light source 240 is disposed, and the light shielding pattern 320 may be disposed to cover the hole H. Therefore, an area S of each of the light shielding patterns 320 may be equal to or greater than an area of ​​an entrance of each of the concave portions 311 .

[0112] Alternatively, in another example, the area S of each of the light shielding patterns 320 may be smaller than the area of ​​the entrance of each of the recessed portions 311. In the above example, when the light guide portion 270 is provided to cover a portion of the top surface of the reflective plate 260, the area of ​​the entrance of the recessed portion 311 may also increase. When each of the light shielding patterns 320 is provided on the same area as that of each hole H, the area S of each of the light shielding patterns 320 may be smaller than the area of ​​the entrance of each of the recessed portions 311.

[0113] The light shielding patterns 320 may be provided by printing a light shielding material such as ink on the second light guide layer 310 b <Case A> or by etching a top surface of the second light guide layer 310 b <Case B>.

[0114] In addition, the light shielding pattern 320 may be positioned to correspond to the hole H of the reflective plate 260 in which the light source 240 is disposed, or may be positioned to partially correspond to a position around the hole H.

[0115] Figure 6 It shows that the setting Figure 5 FIG. 3 is a diagram showing an exemplary structure of a light shielding pattern 320 on a light guide film 300 .

[0116] Reference Figure 6 A light guide portion 270 having a convex top surface is disposed in the hole H of the reflective plate 260 in which the light source 240 is disposed. A light guide film 300 may be disposed on the reflective plate 260 and the light guide portion 270 .

[0117] The light guide film 300 may include a first light guide layer 310a including a concave portion 311 on a bottom surface of the first light guide layer 310a, a second light guide layer 310b disposed on the first light guide layer 310a, and a light shielding pattern 320 disposed on the second light guide layer 310b.

[0118] The light shielding pattern 320 may be disposed to correspond to the light source 240. The light shielding pattern 320 may be disposed to overlap with the hole H in which the light source 240 is disposed. That is, the light shielding pattern 320 may be disposed to correspond to the light source 240 one by one, and the area S of the light shielding pattern 320 may be equal to the area of ​​the hole H in which the light source 240 is disposed.

[0119] Therefore, the light guide part 270 , the first light guide layer 310 a , and the second light guide layer 310 b disposed on the light source 240 may provide a light guiding function and may dispose the light shielding pattern 320 in a region having a maximum light emission intensity, thereby preventing image quality from being degraded.

[0120] Furthermore, when necessary, the light shielding pattern 320 may include a plurality of portions having different reflectivities.

[0121] Figure 7 It shows that the setting Figure 5 FIG. 1 is a diagram showing another exemplary structure of a light shielding pattern 320 on a light guide film 300 .

[0122] Reference Figure 7 The light source 240 is disposed in the hole H of the reflective plate 260 , and a light guide portion 270 surrounding the light source 240 may be disposed in the hole H. The light guide portion 270 may be convex on a top surface thereof, and a light guide film 300 may be disposed on the light guide portion 270 .

[0123] The light guide film 300 may be disposed to directly contact the light guide part 270 and the reflective plate 260 , and include a first light guide layer 310 a , a second light guide layer 310 b , and a light shielding pattern 320 .

[0124] The light shielding pattern 320 may include a first portion 321 having a first reflectivity, and a second portion 322 having a second reflectivity smaller than the first reflectivity, the second portion 322 being defined to surround the first portion 321. That is, the first portion 321 may provide a strong light shielding function, and the second portion 322 may provide a weaker light shielding function than the first portion 321.

[0125] The first portion 321 may be positioned to correspond to the hole H of the reflection plate 260 , and the second portion 322 may be positioned to correspond to a position around the hole H of the reflection plate 260 .

[0126] Since the first portion 321 having a high reflectivity corresponds to the hole H of the reflective plate 260 in which the light source 240 is disposed, light in an area having a strong luminous intensity can be shielded. In addition, the light shielding pattern 320, particularly the second portion 322 having a lower reflectivity than the first portion 321, is disposed around the hole H to efficiently provide a light shielding function, thereby increasing the luminous uniformity of the backlight unit.

[0127] That is, when the light emitted from the light source 240 reaches the first portion 321 of the light shielding pattern 320, most of the light is reflected toward the reflective plate 260 and is supplied to the area between the light sources 240 through the light guide layer 310 of the light guide film 300 and the reflective plate 260, as shown in reference numeral ①. In addition, when the light emitted from the light source 240 reaches the second portion 322 of the light shielding pattern 320, a portion of the light may be transmitted through the second portion 322, as shown in reference numeral ②, while another portion of the light may be reflected, as shown in reference numeral ③. The light reflected from the second portion 322 of the light shielding pattern 320 may be supplied to the area between the light sources 240 through the light guide layer 310 of the light guide film 300 and the reflective plate 260.

[0128] Therefore, light may be uniformly supplied to regions corresponding to the holes H of the light sources 240 , regions around the holes H, and regions between the light sources 240 , thereby improving the overall image quality of the backlight unit.

[0129] For example, by making the ratio of the light shielding material provided in each portion to the portion different, the reflectivity of the first portion 321 and the reflectivity of the second portion 322 of the light shielding pattern 320 may be controlled.

[0130] Fig. 8A , Figure 8B and Figure 8C It is shown Figure 7 The figure shows an example of a specific implementation method of the structure of the shading pattern 320.

[0131] Reference Fig. 8A , Figure 8B and Figure 8C The light shielding pattern 320 disposed on the second light guide layer 310 b of the light guide film 300 may include a first portion 321 having a first reflectivity and a second portion 322 having a second reflectivity smaller than the first reflectivity.

[0132] The first portion 321 may be disposed to correspond to the hole H of the reflective plate 260 in which the light source 240 is arranged, and at least a portion of the second portion 322 may be disposed to overlap with a region around the hole H.

[0133] A ratio of the light shielding material disposed in the first portion 321 to the first portion 321 may be greater than a ratio of the light shielding material disposed in the second portion 322 to the second portion 322 .

[0134] For example, as in Fig. 8A As in the example of FIG. 3 , the light shielding material may be disposed throughout the entire first portion 321. The light shielding material may be disposed in a predetermined pattern. It is only provided in a partial area of ​​the second portion 322. Fig. 8A In the example of FIG. 3 , the light shielding material is shown as being disposed in the second portion 322 in a diamond pattern, but the light shielding material may be disposed in the second portion 322 in any other pattern other than a diamond, a grid, or the like.

[0135] That is, the presence of a partial area of ​​the second portion 322 without the light shielding material may cause the reflectivity of the second portion 322 to be lower than the reflectivity of the first portion 321 .

[0136] In addition, despite the Fig. 8A The examples in which the light shielding material is provided in a predetermined pattern are shown, however, when necessary, a portion without the light shielding material may be formed in a predetermined pattern.

[0137] For example, as in Figure 8B As in the example of FIG. 3 , no light shielding material is provided in the ring-shaped region in each of the first portion 321 and the second portion 322 of the light shielding pattern 320. The width of each ring may be uniform.

[0138] Since there are areas without shading material in the first part 321 and the second part 322 and the ratio of the area without shading material in the first part 321 is different from the ratio of the area without shading material in the second part 322, the reflectivity of the first part 321 and the reflectivity of the second part 322 can be different.

[0139] Since the area in which the shading material is provided is a predetermined pattern, or the area in which the shading material is not provided is a predetermined pattern, it is possible to easily realize a shading pattern 320 including a first portion 321 having a high first reflectivity and a second portion 322 having a low second reflectivity.

[0140] Alternatively, the first portion 321 and the second portion 322 may have different reflectivities by providing light shielding materials having the same shape and size but different densities in the first portion 321 and the second portion 322 .

[0141] For example, as in Figure 8C As in the example of , the light shielding pattern 320 can be implemented by arranging the light shielding material into a plurality of dots. In this case, the density of the dots of the light shielding material arranged in the first portion 321 of the light shielding pattern 320 can be higher than the density of the dots of the light shielding material arranged in the second portion 322 of the light shielding pattern 320.

[0142] Therefore, the light shielding pattern 320 in which the reflectivity gradually decreases from a point corresponding to the hole H in which the light source 240 is disposed may be implemented.

[0143] As such, the light shielding pattern 320 has different reflectivities in different regions, so that light can be diffused from a region corresponding to the hole H in which the light source 240 is disposed and a region around the hole H.

[0144] Furthermore, light is uniformly supplied to the area between the light sources 240. The resulting increase in the gap between the light sources 240 may result in a reduction in the number of light sources 240 included in the backlight unit while maintaining image quality.

[0145] Although the above-mentioned optical sheet may be directly disposed on these light shielding patterns 320 , a configuration for protecting the light shielding patterns 320 and preventing an air gap between the optical sheet disposed on the light shielding patterns 320 and the light guide film 300 may be added.

[0146] Fig. 9 is a diagram illustrating another exemplary cross-sectional structure of a backlight unit according to an embodiment of the present disclosure.

[0147] Reference Fig. 9 , a light source 240 may be disposed on the printed circuit 230, and a reflective plate 260 including a plurality of holes H may be disposed. The light source 240 may be disposed in the hole H of the reflective plate 260, and a light guide 270 may be disposed around the light source 240 in the hole H. That is, the light guide 270 may be disposed in each hole H.

[0148] The top surface of the light guide portion 270 may be shaped to be convex to improve the light extraction function and facilitate attachment to the light guide film 300. The light guide film 300 may be disposed on the light guide portion 270 and the reflective plate 260.

[0149] The light guide film 300 may include: a first light guide layer 310a in contact with the reflective plate 260 and the light guide portion 270; a second light guide layer 310b disposed on the first light guide layer 310a; and a light shielding pattern 320 disposed on the second light guide layer 310b. In addition, the light guide film 300 may further include a coating layer 330 disposed on the second light guide layer 310b and the light shielding pattern 320.

[0150] The first light guide layer 310a may include a concave portion 311 on a bottom surface thereof corresponding to the convex top surface of the light guide portion 270, and provide an adhesion function and a light guide function. The top surface of the first light guide layer 310a may be flat.

[0151] The second light guide layer 310 b may be disposed on the first light guide layer 310 a to provide a light guiding function, and the second light guide layer 310 b may have a flat top surface.

[0152] The light shielding pattern 320 may be disposed on the second light guide layer 310 b corresponding to the light source 240 to provide a light shielding function, thereby preventing a hot spot and improving image quality.

[0153] As in the above-described example, each of the light shielding patterns 320 may have different reflectivities in a portion corresponding to the hole H and a portion corresponding to an area around the hole H, so that light may be uniformly diffused around the light shielding patterns 320 .

[0154] The coating layer 330 may be disposed on the light shielding pattern 320 .

[0155] The coating layer 330 may be disposed on the top surfaces of the second light guide layer 310 b and the light shielding pattern 320 and have a flat top surface. When necessary, the coating layer 330 may be implemented as a part of the light guide film 300 or be disposed separately from the light guide film 300 .

[0156] Since the coating layer 330 is disposed on the second light guide layer 310 b and the light shielding pattern 320 , the coating layer 330 may protect the light shielding pattern 320 and cause planarization of the top surface of the light guide film 300 .

[0157] Therefore, it is possible to prevent damage to the light shielding pattern 320 that may otherwise be caused by an optical member such as a diffuser plate 400 disposed on the light guide film 300. In particular, when each of the light shielding patterns 320 has different reflectances in different regions, the light shielding material may be disposed in a different shape in each region. When the diffuser plate 400 or the like deforms the layout of the light shielding material, the expected reflectance may not be accurately obtained.

[0158] Since damage to the light shielding pattern 320 is prevented by providing the coating layer 330 on the light shielding pattern 320 in the above-described manner, the light shielding patterns 320 each having different reflectivities in different regions may be implemented.

[0159] Furthermore, planarizing the top surface of the light guide film 300 by disposing the coating layer 330 on the light guide film 300 may result in no air gap between the light guide film 300 and an optical member disposed on the light guide film 300 .

[0160] Therefore, total reflection of light emitted from the air gap through the light guide layer 310 of the light guide film 300 and reduction in light emission efficiency caused thereby may be prevented.

[0161] Furthermore, in an embodiment of the present disclosure, the light guide layer 310 included in the light guide film 300 may be formed in various structures to improve light guiding performance and diffusion performance of the light guide film 300 while further reducing the thickness of the backlight unit.

[0162] Fig.10 , Fig.11 and Fig.12 is a diagram illustrating other exemplary cross-sectional structures of a backlight unit according to an embodiment of the present disclosure.

[0163] Reference Fig.10 The backlight unit may include a light source 240 disposed on a printed circuit 230 and a reflective plate 260 disposed on the printed circuit 230 and including a hole H positioned in a region corresponding to the light source 240. A light guide 270 may be disposed in the hole H of the reflective plate 260.

[0164] The light guide film 300 may be disposed on the light guide part 270. Similar to the aforementioned example, the diffusion plate 400, the color conversion sheet 500, the prism sheet 600, and the diffusion sheet 700 may be disposed on the light guide film 300.

[0165] The light guide film 300 may include a light guide layer 310 contacting the light guide part 270 and a light shielding pattern 320 disposed on the light guide layer 310. That is, the light guide layer 310 of the light guide film 300 may be disposed to directly contact the light guide part 270.

[0166] Since light guide layer 310 is disposed in direct contact with light guide portion 270, it is possible to prevent a reduction in light diffusion performance that may otherwise be caused by the arrangement of an adhesive layer between light guide layer 310 and light guide portion 270. In addition, since light diffusion performance is improved by light guide film 300, light guide performance and diffusion performance can be maintained or improved while the overall thickness of light guide film 300 can be reduced.

[0167] For example, since the light guide layer 310 is directly disposed on the light guide part 270 , the light guide part 270 may provide an adhesion function. When the light guide part 270 provides an adhesion function, a portion of each of the light guide parts 270 may be disposed on the reflective plate 260 .

[0168] That is to say, Fig.10 As shown, the light guide portion 270 may be disposed inside the hole H of the reflective plate 260 and on the top surface of the reflective plate 260 , and the light guide film 300 may be attached to the light guide portion 270 .

[0169] Alternatively, in some cases, the light guide film 300 may be attached with the light guide part 270 filled only in the hole H of the reflective plate 260 .

[0170] In this case, the light guide portion 270 may not be disposed on the top surface of the reflective plate 260. Alternatively, a portion of each of the light guide portions 270 may be disposed only on a partial area of ​​the top surface of the reflective plate 260. That is, there may be an area on the top surface of the reflective plate 260 where the light guide portion 270 is not disposed.

[0171] In a structure in which a portion of each of the light guide portions 270 is disposed on the reflective plate 260, the top surface of the light guide portion 270 disposed in the hole H of the reflective plate 260 may be convex, or may be flat when necessary. When the top surface of the light guide portion 270 is convex, the bottom surface of the light guide layer 310 may include a concave portion 311 positioned in an area corresponding to the light guide portion 270.

[0172] In this way, due to the adhesion function provided by the light guide portion 270, the light guide layer 310 of the light guide film 300 can be directly disposed on the light guide portion 270, thereby preventing the reduction of light diffusion performance that may otherwise be caused by the adhesive layer with low transmittance. In addition, the light guide film 300 can improve the light guide performance and the diffusion performance, and can increase the brightness and light efficiency of the backlight unit.

[0173] Alternatively, when an adhesive layer is provided between the light guide film 300 and the light guide part 270 , the light guide film 300 may include a layer having a light diffusion function to improve light diffusion performance.

[0174] Reference Fig.11, the light source 240 may be disposed on the printed circuit 230 , and a reflective plate 260 including a plurality of holes H may be disposed. A light guide 270 may be disposed inside the holes H of the reflective plate 260 .

[0175] The light guide film 300 may be disposed on the light guide part 270 and the reflective plate 260 .

[0176] The light guide film 300 may include: a first light guide layer 310 a providing an adhesion function and a light guide function; a second light guide layer 310 b disposed on the first light guide layer 310 a ; and a light shielding pattern 320 disposed on the second light guide layer 310 b .

[0177] The first light guide layer 310a may be disposed in contact with the top surface of the light guide part 270 and the top surface of the reflective plate 260. The bottom surface of the first light guide layer 310a may include a concave portion 311 corresponding to the convex shape of the light guide part 270.

[0178] The second light guide layer 310 b may be disposed on the first light guide layer 310 a and provide a light guiding function.

[0179] A plurality of light diffusion particles 340 may be disposed on at least one surface of the second light guide layer 310 b or inside the second light guide layer 310 b .

[0180] For example, as shown in the first example EX 1, a plurality of light diffusion particles 340 may be disposed on the top surface of the second light guide layer 310b. Alternatively, in some cases, a plurality of light diffusion particles 340 may be disposed only on the bottom surface of the second light guide layer 310b. These light diffusion particles 340 may be coated on one surface of the second light guide layer 310b.

[0181] When the light diffusion particles 340 are disposed on the top surface of the second light guide layer 310b, the light diffusion particles 340 may be arranged to spread over the entire top surface of the second light guide layer 310b and overlap with the region in which the light shielding pattern 320 is disposed. Alternatively, the light diffusion particles 340 may be disposed only in a region without the light shielding pattern 320 on the top surface of the second light guide layer 310b.

[0182] In another example, as shown in the second example EX2, a plurality of light diffusion particles 340 may be provided on both the top and bottom surfaces of the second light guide layer 310. The light diffusion particles 340 may be arranged to spread over the entire bottom surface of the second light guide layer 310b. In addition, the light diffusion particles 340 may be arranged to spread over the entire top surface of the second guide layer 310b or only in an area without the light shielding pattern 320.

[0183] In another example, as shown in a third example EX3, a plurality of light diffusion particles 340 may be arranged inside the second light guide layer 310 b .

[0184] That is, the light diffusion particles 340 providing a light diffusion function may be disposed on an outer surface or inside the second light guide layer 310 b .

[0185] For example, the light diffusion particles 340 may be, but are not limited to, beads.

[0186] The arrangement of the light diffusing particles 340 included in the second light guide layer 310 b in the light guide film 300 may result in improved light diffusing performance.

[0187] Therefore, even when the light guide film 300 includes the first light guide layer 310 a providing an adhesion function, the light guide film 300 may improve light diffusion performance and increase brightness and light efficiency of the backlight unit.

[0188] In addition, since the light guide layer 310 providing a light diffusion function is directly attached to the light guide part 270 , the light diffusion performance of the light guide film 300 may be further increased.

[0189] Reference Fig.12 , a reflective plate 260 including a hole H may be disposed on the printed circuit 230 on which the light source 240 is disposed. A light guide portion 270 may be disposed inside the hole H of the reflective plate 260 . A light guide film 300 may be disposed on the light guide portion 270 .

[0190] The light guide film 300 may include a light guide layer 310 disposed on the light guide part 270 and a light shielding pattern 320 disposed on a top surface of the light guide layer 310 .

[0191] In addition, the light guide film 300 may include a plurality of light diffusion particles 340 disposed on at least one of the top and bottom surfaces of the light guide layer 310. Alternatively, the light diffusion particles 340 may be positioned inside the light guide layer 310.

[0192] Since the light diffusion performance of the light guide layer 310 is improved due to the arrangement of the light diffusion particles 340 on the outer surface or inside of the light guide layer 310 , the brightness and light efficiency of the backlight unit may be increased.

[0193] Furthermore, the absence of a low-transmittance adhesive layer between the light guide layer 310 and the light guide portion 270 can prevent a reduction in light diffusion performance that may otherwise be caused by the adhesive layer, and further increase the brightness and light efficiency of the backlight unit.

[0194] Since the light guide layer 310 is in direct contact with the top surface of the light guide part 270 , the light guide part 270 may provide an adhesion function.

[0195] In addition, a portion of each of the light guide parts 270 may be positioned on the top surface of the reflective plate 260. The light guide layer 310 may be attached through the light guide parts 270 positioned on the top surface of the reflective plate 260.

[0196] In a structure in which a portion of each of the light guide portions 270 is disposed on the top surface of the reflective plate 260, the top surface of the light guide portion 270 disposed in the hole H of the reflective plate 260 may be convex. Alternatively, in some cases, the top surface of the light guide portion 270 disposed in the hole H of the reflective plate 260 may be flat.

[0197] When the top surface of the light guide portion 270 disposed in the hole H of the reflective plate 260 is convex, the bottom surface of the light guide layer 310 disposed on the light guide portion 270 may include a concave portion 311 .

[0198] Thus, the adhesive film can be removed from between the light guide film 300 and the light guide part 270, and a light diffusion function can be imparted to the light guide layer 310 of the light guide film 300, thereby increasing the light diffusion efficiency of the light guide film 300. Therefore, the brightness and light efficiency of the backlight unit can be increased.

[0199] Fig.13 is a table listing test results of performance of various backlight unit structures according to embodiments of the present disclosure.

[0200] Reference Fig.13 , Case 1 shows the measurement results of brightness, image quality, and power consumption when the light guide film 300 disposed on the light guide part 270 in the backlight unit includes a first light guide layer 310a providing an adhesion function, a second light guide layer 310b providing a light guiding function, and a light shielding pattern 320.

[0201] also, Fig.13 The measurement results of the luminance and the power consumption in the backlight units including the light guide films of different structures with respect to the measured luminance and the power consumption of Case 1 being 100% are shown.

[0202] Case 2 shows the measurement results of brightness and the like in a structure in which the light guide film 300 is disposed on the light guide portion 270 without an adhesive layer between the light guide film 300 and the light guide portion 270 .

[0203] It should be noted that since the light guide layer 310 of the light guide film 300 is disposed on the light guide portion 270 without an adhesive layer between the light guide film 300 and the light guide portion 270, and the light shading pattern 320 is disposed on the light guide layer 310, Case 2 has an improved brightness of 107% and a reduced power consumption of 92% relative to Case 1 while maintaining image quality (BLUFOS: Backlight Unit Front Of Sight).

[0204] Case 3 shows the measurement results of brightness, etc. when the light guide film 300 arranged on the light guide portion 270 includes a first light guide layer 310a providing an adhesion function, a second light guide layer 310b arranged on the first light guide layer 310a, a shading pattern 320 arranged on the second light guide layer 310b, and light diffusing particles 340 arranged on at least one surface of the second light guide layer 310b or inside the second light guide layer 310b.

[0205] Although the first light guide layer 310a providing the adhesion function is provided, the second light guide layer 310b provides the diffusion function through the light diffusion particles 340, thereby improving the light diffusion performance of the light guide film 300. Fig.13 As shown, it can be noted that Case 3 has 110% improved brightness and 90% reduced power consumption relative to Case 1 while maintaining image quality.

[0206] Case 4 shows a case where the light guide film 300 is disposed on the light guide portion 270 without an adhesive layer between the light guide film 300 and the light guide portion 270. In addition, Case 4 shows measurement results of brightness and the like when the light guide film 300 includes a light guide layer 310, a light shielding pattern 320 disposed on a top surface of the light guide layer 310, and light diffusion particles 340 disposed on at least one surface of the light guide layer 310 or inside the light guide layer 310.

[0207] It can be noted that Case 4 has 108% improved brightness and 91% reduced power consumption relative to Case 1, since the adhesive layer that reduces the light diffusion performance is removed and the light diffusion performance of the light guide layer 310 is improved.

[0208] In addition, in terms of light diffusion performance, the light guide layer 310 in case 4 is inferior to the light guide film 300 in case 3. Therefore, case 4 can provide a similar level of light efficiency while reducing costs compared to case 3. In addition, when the light guide layer 310 of case 4 has the same light diffusion performance as the light guide film 300 of case 3, case 4 can have the highest light efficiency due to the absence of an adhesive layer structure.

[0209] According to the above-mentioned embodiment of the present disclosure, since in the structure in which the light source 240 is arranged in the hole H of the reflective plate 260, the light guide portion 270 is arranged in each hole H, and the light guide film 300 is arranged on the reflective plate 260 and the light guide portion 270, a backlight unit with a small thickness that satisfies image quality can be provided.

[0210] In addition, the backlight unit may be easily implemented by directly disposing the light guide film 300 on the light guide part 270 and the reflective plate 260 .

[0211] Furthermore, since each of the light shielding patterns 320 has different reflectivity in different regions, more light can be supplied to the region between the light sources 240. The resulting increase in the gap between the light sources 240 and maintenance of image quality can lead to a reduction in the number of light sources 240.

[0212] In addition, when necessary, the light guide film 300 is directly attached to the light guide portion 270, which eliminates the need to arrange an adhesive layer that reduces light diffusion performance between the light guide film 300 and the light guide portion 270, or the light guide layer 310 of the light guide film 300 has a light diffusion function. The resulting improvement in the light diffusion performance of the light guide film 300 can lead to a further increase in the light efficiency of the backlight unit while maintaining the image quality of the backlight unit.

[0213] For example, the present disclosure may also include the following technical solutions:

[0214] Solution 1. A display device, comprising:

[0215] display panel; and

[0216] a backlight unit that supplies light to the display panel,

[0217] Wherein, the backlight unit comprises:

[0218] a plurality of light sources disposed on the printed circuit;

[0219] a reflective plate, the reflective plate being disposed on the printed circuit and comprising a plurality of holes, wherein the plurality of light sources are respectively disposed in the plurality of holes;

[0220] a plurality of light guide portions, the plurality of light guide portions being respectively disposed in the plurality of holes to surround the plurality of light sources; and

[0221] A light guide film is disposed on the reflective plate and the plurality of light guide portions and includes at least one light guide layer and a plurality of light shielding patterns, wherein the plurality of light shielding patterns are positioned on a top surface of the light guide layer corresponding to the plurality of light sources, respectively.

[0222] Solution 2. The display device according to Solution 1, wherein a top surface of each of the plurality of light guide portions is convex, and at least a portion of the top surface of the light guide portion is positioned higher than a top surface of the reflective plate.

[0223] Solution 3. The display device according to Solution 1, wherein top surfaces of the plurality of light guide portions are positioned on the same plane as a top surface of the reflection plate.

[0224] Solution 4. The display device according to Solution 1, wherein top surfaces of the plurality of light guide portions are in direct contact with a bottom surface of the light guide film.

[0225] Solution 5. The display device according to Solution 4, wherein a portion of each of the plurality of light guide portions is positioned on a top surface of the reflective plate.

[0226] Solution 6. The display device according to Solution 1, wherein the light guide film further comprises:

[0227] A plurality of light diffusion particles are disposed on at least one surface of the light guide layer or inside the light guide layer.

[0228] Solution 7. The display device according to Solution 1, wherein the light guide film comprises:

[0229] a first light guide layer that contacts a top surface of the reflection plate and top surfaces of the plurality of light guide portions and has a flat top surface; and

[0230] A second light guide layer is disposed on the first light guide layer and has a top surface on which the plurality of light shielding patterns are disposed.

[0231] Solution 8. A display device according to Solution 7, wherein a thickness of a thickest portion of the first light guide layer is greater than a vertical distance between a highest point of each of the plurality of light guide portions and a highest point of the reflective plate.

[0232] Solution 9. The display device according to Solution 1 further includes an adhesive layer, which is arranged between the reflective plate and the multiple light guide parts and the light guide film, and has a bottom surface in contact with the reflective plate and the multiple light guide parts and a flat top surface.

[0233] Solution 10. The display device according to Solution 1, wherein each of the plurality of light shielding patterns comprises:

[0234] a first portion having a first reflectivity; and

[0235] A second portion is positioned outside the first portion and has a second reflectivity that is less than the first reflectivity.

[0236] Option 11. A display device according to Option 10, wherein the ratio of the area of ​​the shading material arranged in the first part to the total area of ​​the first part is greater than the ratio of the area of ​​the shading material arranged in the second part to the total area of ​​the second part.

[0237] Solution 12. The display device according to Solution 10, wherein the first portion is positioned to correspond to the hole, and at least a portion of the second portion overlaps with a portion of the reflective plate other than the hole.

[0238] Option 13. A display device according to Option 1, wherein the light guide film further comprises a coating layer that protects the plurality of light-shielding patterns and has a flat top surface, the coating layer being disposed on the top surface of the light guide layer on which the plurality of light-shielding patterns are disposed.

[0239] Solution 14. A backlight unit, comprising:

[0240] a plurality of light sources disposed on the printed circuit;

[0241] a reflective plate, the reflective plate being disposed on the printed circuit and comprising a plurality of holes, wherein the plurality of light sources are respectively disposed in the plurality of holes;

[0242] a plurality of light guide portions, the plurality of light guide portions being respectively disposed in the plurality of holes to surround the plurality of light sources; and

[0243] A light guide film is disposed on the reflective plate and the plurality of light guide portions and includes at least one light guide layer and a plurality of light shielding patterns, wherein the plurality of light shielding patterns are positioned on a top surface of the light guide layer corresponding to the plurality of light sources, respectively.

[0244] Solution 15. A light-guiding film, comprising:

[0245] a first light guide layer including a plurality of concave portions on one surface and having another surface opposite to the one surface being flat;

[0246] a second light guide layer that contacts the other surface of the first light guide layer and has two flat surfaces; and

[0247] A plurality of light shielding patterns are provided on a surface of the second light guide layer except a surface of the second light guide layer in contact with the first light guide layer.

[0248] Option 16. The light-guiding film according to Option 15, wherein the plurality of light-shielding patterns are respectively arranged at positions corresponding to the plurality of recessed portions.

[0249] Embodiment 17. The light-guiding film according to Embodiment 16, wherein an area of ​​at least one of the plurality of light-shielding patterns is equal to or larger than an area of ​​an entrance of a recessed portion corresponding to the light-shielding pattern.

[0250] Solution 18. The light guide film according to Solution 15, wherein each of the plurality of light shielding patterns comprises: a first portion having a first reflectivity; and a second portion disposed outside the first portion and having a second reflectivity smaller than the first reflectivity; and

[0251] The first portion is disposed at a position corresponding to the recessed portion, and at least a portion of the second portion is disposed at a position corresponding to a position around the recessed portion.

[0252] Option 19. The light-guiding film according to Option 15 further includes a coating for protecting the multiple light-shielding patterns, wherein the coating is disposed on a surface of the second light-guiding layer on which the multiple light-shielding patterns are disposed, one of the two surfaces of the second light-guiding layer, and a surface of the coating opposite to a surface in contact with the second light-guiding layer and the multiple light-shielding patterns is flat.

[0253] Solution 20. The light guiding film according to Solution 15 further comprises a plurality of light diffusing particles, wherein the plurality of light diffusing particles are disposed on at least one of the two surfaces of the second light guiding layer or inside the second light guiding layer.

[0254] The above description has been presented to enable any person skilled in the art to implement and use the technical concept of the present invention, and the above description has been provided in the context of a specific application and its needs. Various modifications, additions and substitutions to the described embodiments will be 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 invention. The above description and accompanying drawings provide examples of the technical concept of the present invention for illustrative purposes only. That is, the disclosed embodiments are intended to illustrate the scope of the technical concept of the present invention. Therefore, the scope of the present invention is not limited to the embodiments shown, but should have the widest scope consistent with the claims. The scope of protection of the present invention should be interpreted based on the attached claims, and all technical concepts within their equivalent ranges should be interpreted as included within the scope of the present invention.

Claims

1. A display device, comprising: Display panel; as well as a backlight unit that supplies light to the display panel, Wherein, the backlight unit comprises: a plurality of light sources disposed on the printed circuit; a reflective plate, the reflective plate being disposed on the printed circuit and comprising a plurality of holes, wherein the plurality of light sources are respectively disposed in the plurality of holes; a plurality of light guide portions, the plurality of light guide portions being respectively disposed in the plurality of holes to surround the plurality of light sources; and a light guide film, the light guide film being disposed on the reflective plate and the plurality of light guide portions, and comprising a first light guide layer, a second light guide layer disposed on the first light guide layer, and a plurality of light shielding patterns, the plurality of light shielding patterns being located on the second light guide layer and being positioned corresponding to the plurality of light sources, respectively; The top surface of the second light guide layer includes a plurality of parts, each of the plurality of parts has a plurality of protrusions, wherein each of the plurality of light shielding patterns is positioned in each of the plurality of portions of the second light guide layer such that each light shielding pattern has a flat top surface and a bottom surface having a plurality of protrusions, Wherein, the bottom surface of the first light guide layer includes a plurality of concave portions, Wherein, each of the plurality of light shielding patterns is positioned corresponding to the plurality of concave portions respectively.

2. The display device according to claim 1, wherein: The size of the protrusions located in the central area of ​​each portion among the plurality of protrusions is greater than the size of the protrusions located in the edge area of ​​each portion.

3. The display device according to claim 1, wherein: Each of the plurality of light shielding patterns comprises: a first portion having a first reflectivity; and a second portion positioned outside the first portion and having a second reflectivity less than the first reflectivity, and Wherein, the first portion is disposed at a position corresponding to a corresponding hole among the plurality of holes and does not extend beyond the hole.

4. The display device according to claim 1, wherein: The light guide film further comprises: a plurality of light diffusion particles, wherein the plurality of light diffusion particles are arranged on at least one surface of the light guide layer. The plurality of light diffusion particles do not overlap with the plurality of light shielding patterns.

5. The display device according to claim 1, wherein: The plurality of light guide portions provide an adhesion function, and a portion of each of the plurality of light guide portions is positioned on a top surface of the reflection plate.

6. The display device according to claim 1, wherein: Top surfaces of the plurality of light guide parts are in direct contact with the bottom surface of the second light guide layer.

7. The display device according to claim 1, wherein: A top surface of each of the plurality of light guides is convex.

8. The display device according to claim 1, wherein: A ratio of an area of ​​the light shielding material disposed in the first portion to a total area of ​​the first portion is greater than a ratio of an area of ​​the light shielding material disposed in the second portion to a total area of ​​the second portion.

9. The display device according to claim 1, wherein: The light guide film further includes a coating layer disposed on a top surface of the second light guide layer on which the plurality of light shielding patterns are disposed.

10. The display device according to claim 1, wherein: The first light guide layer has an adhesion function, and the first light guide layer directly contacts a lower surface of the second light guide layer and corresponding top surfaces of the reflection plate and the plurality of light guide parts through the adhesion function.

11. A backlight unit, comprising: a plurality of light sources disposed on the printed circuit; a reflective plate, the reflective plate being disposed on the printed circuit and comprising a plurality of holes, wherein the plurality of light sources are respectively disposed in the plurality of holes; a plurality of light guide portions, the plurality of light guide portions being respectively disposed in the plurality of holes to surround the plurality of light sources; as well as a light guide film, the light guide film being disposed on the reflective plate and the plurality of light guide portions, and comprising a first light guide layer, a second light guide layer disposed on the first light guide layer, and a plurality of light shielding patterns, the plurality of light shielding patterns being disposed on the light guide layer and positioned corresponding to the plurality of light sources, respectively; The top surface of the second light guide layer includes a plurality of parts, each of the plurality of parts has a plurality of protrusions, wherein each of the plurality of light shielding patterns is positioned in each of the plurality of portions of the second light guide layer such that each light shielding pattern has a flat top surface and a bottom surface having a plurality of protrusions, Wherein, the bottom surface of the first light guide layer includes a plurality of concave portions, The first light guide layer has an adhesion function, and the first light guide layer directly contacts the bottom surface of the second light guide layer and the corresponding top surfaces of the reflective plate and the plurality of light guide parts through the adhesion function.

12. The display device according to claim 11, wherein: The size of the protrusions located in the central area of ​​each portion among the plurality of protrusions is greater than the size of the protrusions located in the edge area of ​​each portion.

13. The display device according to claim 11, wherein: Each of the plurality of light shielding patterns comprises: a first portion having a first reflectivity; and a second portion positioned outside the first portion and having a second reflectivity that is smaller than the first reflectivity, Wherein, the first portion is disposed at a position corresponding to a corresponding hole among the plurality of holes and does not extend beyond the hole.

14. The display device according to claim 11, wherein: The light guide film further comprises: a plurality of light diffusion particles, wherein the plurality of light diffusion particles are arranged on at least one surface of the light guide layer. The plurality of light diffusion particles do not overlap with the plurality of light shielding patterns.

15. The display device according to claim 11, wherein: The plurality of light guide portions provide an adhesion function, and a portion of each of the plurality of light guide portions is positioned on a top surface of the reflection plate.

16. The display device according to claim 11, wherein: Top surfaces of the plurality of light guide parts are in direct contact with the bottom surface of the second light guide layer.

17. The display device according to claim 11, wherein: The light guide film further includes a coating layer disposed on a top surface of the second light guide layer on which the plurality of light shielding patterns are disposed.

18. The display device according to claim 11, wherein: The bottom surface of the first light guide layer includes a plurality of concave portions, and Wherein, each of the plurality of light shielding patterns is positioned corresponding to the plurality of concave portions respectively.

19. A light guide film, comprising: a first light guide layer having a first surface including a plurality of concave portions thereon, and a second surface that is flat and opposite to the first surface; a second light guide layer having a third surface that contacts the second surface of the first light guide layer and has a flat surface, and a fourth surface that is opposite to the third surface; The fourth surface of the second light guide layer includes a plurality of parts, each of the plurality of parts has a plurality of protrusions, wherein each of the plurality of light shielding patterns is positioned in each of the plurality of portions of the second light guide layer such that each light shielding pattern has a flat top surface and a bottom surface having a plurality of protrusions, Among the plurality of protrusions, a size of a protrusion located in a central area of ​​each portion is greater than a size of a protrusion located in an edge area of ​​each portion.

20. The display device according to claim 11, wherein: The first light guide layer has an adhesion function, and the first light guide layer directly contacts a lower surface of the second light guide layer through the adhesion function.

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