A display device including a viewing angle control unit

Abstract

To provide a display device including a viewing angle control unit capable of limiting a traveling path of light.SOLUTION: A display device may include a liquid crystal panel located on a backlight unit. The backlight unit may include a second light guide plate located on a first light guide plate. A viewing angle control unit may be located between the first light guide plate and the second light guide plate. The liquid crystal panel may include a first display area and a second display area. The viewing angle control unit may include a light shielding pattern overlapping the first display area. The second display area of the liquid crystal panel may be located outside the light shielding pattern. Thus, in the display device, a first image provided to a user located in a specific direction and a second image shared with persons around the user are realized simultaneously, and the persons around the user may not recognize the first image.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present invention relates to a display device including a viewing angle control unit capable of restricting the traveling path of light.

Background Art

[0002] Generally, a display device embodies an image. For example, the display device can include a liquid crystal panel positioned on a backlight unit. The backlight unit can supply light to the liquid crystal panel. For example, the backlight unit can include at least one light source element. The liquid crystal panel can embody a specific image by using an electric field formed between a pixel electrode and a common electrode. For example, the liquid crystal panel can include a liquid crystal layer positioned between a first display substrate and a second display substrate.

[0003] The display device can be installed in various places. For example, the display device can be mounted inside an automobile. The display device can embody a first image provided to a person sitting in the passenger seat and / or a second image including information necessary for driving. The second image can be embodied simultaneously with the first image. For example, in the display device, the liquid crystal panel can include a first display area for embodying the first image and a second display area for embodying the second image.

[0004] The first display area and the second display area can be positioned side by side. For example, the first display area can be positioned in front of the passenger seat, and the second display area can be positioned between the driver's seat and the passenger seat. Thereby, in the display device, the driver's line of sight can be dispersed by the first image. That is, in the display device, the line of sight of people around the user can be dispersed by the first image provided to the user positioned in a specific direction, and an accident can occur.

Summary of the Invention

[0005] The problem to be solved by the present invention is to provide a display device that can prevent accidents caused by the distraction of the line of sight of people around the user.

[0006] Another problem to be solved by the present invention is to provide a display device that simultaneously embodies a first image and a second image, but the first image can only be recognized in a specific direction.

[0007] The problems to be solved by the present invention are not limited to the above problems. Problems not mentioned here will be clearly understood by ordinary technicians from the following description.

[0008] The display device according to the technical idea of the present invention for achieving the problems to be solved includes a backlight unit. The backlight unit includes a first light guide plate and a second light guide plate. The second light guide plate is located above the first light guide plate. A liquid crystal panel is located above the second light guide plate of the backlight. The liquid crystal panel includes a first display area and a second display area. A first viewing angle control unit is located between the first light guide plate and the second light guide plate of the backlight unit. The first viewing angle control unit includes a first light-shielding pattern extending in a first direction. The first light-shielding pattern is arranged to correspond to the first display area. The second display area of the liquid crystal panel is located outside the first light-shielding pattern in a second direction perpendicular to the first direction.

[0009] The second display area can be in contact with the first display area. The boundary line between the first display area and the second display area can extend in the first direction.

[0010] A first light source element can be located on the side of the first light guide plate. A second light source element can be located on the side surface of the second light guide plate.

[0011] The first light source element can be mounted on the first circuit board. The second light source element can be mounted on the second circuit board. The second circuit board can be separated from the first circuit board in a third direction perpendicular to the first direction and the second direction.

[0012] The second light source element can be positioned side by side with the first light source element in the third direction.

[0013] The first display area of the liquid crystal panel can be positioned close to the first light source element and the second light source element.

[0014] A second viewing angle control unit can be positioned between the second light guide plate of the backlight unit and the liquid crystal panel. The second viewing angle control unit can include a second light-shielding pattern extending in the second direction.

[0015] The second light-shielding pattern can overlap with the first display area and the second display area of the liquid crystal panel.

[0016] The first viewing angle control unit can further include a relaxation area overlapping with the boundary line between the first display area and the second display area. At least one dummy pattern can be positioned within the relaxation area. The thickness of the dummy pattern may be thinner than the thickness of each first light-shielding pattern.

[0017] The dummy pattern of the first viewing angle control unit can extend in the first direction.

[0018] The display device according to the technical idea of the present invention for achieving other problems to be solved by the present invention includes a first light guide plate. A first light source element is located on one side of the first light guide plate. A second light guide plate is located above the first light guide plate. The second light guide plate overlaps the first light guide plate. A viewing angle control unit is located between the first light guide plate and the second light guide plate. The viewing angle control unit includes a narrow viewing angle region and a wide viewing angle region. There is a light shielding pattern in the narrow viewing angle region. The wide viewing angle region is located outside the light shielding pattern. A liquid crystal panel is located above the second light guide plate. The liquid crystal panel includes a first display region and a second display region. The narrow viewing angle region of the viewing angle control unit overlaps the first display region of the liquid crystal panel. The wide viewing angle region of the viewing angle control unit overlaps the second display region of the liquid crystal panel. A second light source element is located on one side of the second light guide plate.

[0019] The light shielding pattern can extend in a first direction. The second display region can be located side by side with the first display region in a second direction. The second direction can be perpendicular to the first direction. The length of the narrow viewing angle region in the second direction can be the same as the length of the wide viewing angle region in the second direction.

[0020] The viewing angle control unit can further include a dummy light shielding layer corresponding to the wide viewing angle region. The dummy light shielding layer may be smaller than the light shielding pattern.

[0021] The dummy light shielding layer can include the same material as the light shielding pattern.

[0022] The dummy light shielding layer corresponds to the wide viewing angle region, but can be arranged to extend in the first direction and the second direction. That is, it can be arranged to be thinly coated corresponding to the wide viewing angle region. The amount of light transmitted through the light shielding pattern of the viewing angle control pattern and the amount of light transmitted through the dummy light shielding layer can be made substantially the same.

[0023] The display device according to the technical idea of the present invention includes a viewing angle control unit located between a first light guide plate and a second light guide plate of a backlight unit, and a liquid crystal panel located on the second light guide plate of the backlight unit. The liquid crystal panel includes a first display area and a second display area. The viewing angle control unit includes a light-shielding pattern overlapping with the first display area and can be located outside the light-shielding pattern. Thus, in the display device according to the technical idea of the present invention, the first image embodied in the first display area may not be selectively recognized by people around. Therefore, in the display device according to the technical idea of the present invention, accidents due to the dispersion of the line of sight of people around can be prevented.

Brief Description of the Drawings

[0024]

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Embodiments for Carrying Out the Invention

[0025] Details regarding the object, technical configuration, and the resulting operational effects of the present invention will be more clearly understood from the following detailed description with reference to the drawings illustrating the embodiments of the present invention. Here, the embodiments of the present invention are provided to fully convey the technical idea of the present invention to those skilled in the art. Therefore, the present invention can be embodied in other forms so as not to be limited to the embodiments described below.

[0026] Also, parts denoted by the same reference numeral throughout the specification denote the same components, and the lengths and thicknesses of layers or regions in the drawings may be exaggerated for convenience of illustration. When it is described that the first component is "above" the second component, it includes not only the case where the first component is located directly above and in contact with the second component, but also the case where a third component is located between the first component and the second component.

[0027] Here, terms such as the first and second are used to describe various components and are used for the purpose of distinguishing one component from another. However, within the scope not departing from the technical idea of the present invention, the first component and the second component can be arbitrarily named for the convenience of those skilled in the art.

[0028] The terms used in the specification of the present invention are merely used to explain specific embodiments and are not intended to limit the present invention. For example, a component expressed in the singular includes a plurality of components when it is not clearly meant only the singular in the context.

[0029] Also, in the specification of the present invention, terms such as "comprising" or "having" are intended to specify the presence of features, numbers, steps, operations, components, parts, or combinations thereof described above in the specification, and should not be construed as precluding the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0030] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs. Terms defined as in a commonly used dictionary should be interpreted as having a meaning consistent with the meaning in the context of the related art, and should not be interpreted in an ideal or overly formal sense unless clearly defined in the specification of the present invention.

[0031] Embodiment FIG. 1 is a diagram showing the location where the display device according to an embodiment of the present invention is installed. FIG. 2 is a diagram schematically showing the display device according to an embodiment of the present invention. FIG. 3 is a diagram showing a cross-section of a liquid crystal panel and a cross-section of a viewing angle control unit in the display device according to an embodiment of the present invention.

[0032] Referring to FIGS. 1 to 3, the display device DP according to an embodiment of the present invention can be installed in an automobile. The display device DP can include a liquid crystal panel 100. The liquid crystal panel 100 can embody an image by using an electric field formed between a pixel electrode and a common electrode. For example, the liquid crystal panel 100 can include a liquid crystal layer located between a first display substrate and a second display substrate. The liquid crystal layer can include liquid crystal in an IPS mode, an ECB mode, or a TN mode.

[0033] The display device DP can embody a first image for a person sitting in the passenger seat and / or a second image including information necessary for driving. The second image can be embodied simultaneously with the first image. For example, the liquid crystal panel 100 can include a first display area CA and a second display area IA. The first image is embodied in the first display area CA, and the second image can be embodied in the second display area IA. The second display area IA can be located side by side with the first display area CA in a first direction X. For example, the first display area CA of the liquid crystal panel 100 is located in front of the passenger seat PS, and the second display area IA of the liquid crystal panel 100 can be located between the passenger seat PS and the driver's seat DS. The length of the second display area IA can be the same as the length of the first display area CA in the first direction X. The second display area IA can be in direct contact with the first display area CA. For example, the boundary line between the first display area CA and the second display area IA can extend in a third direction Z different from the first direction X.

[0034] The liquid crystal panel 100 can be positioned above the backlight unit 200. For example, the liquid crystal panel 100 and the backlight unit 200 can be stacked in a second direction Y perpendicular to the first direction X. The backlight unit 200 can supply light to the liquid crystal panel 100. For example, the liquid crystal panel 100 can utilize the light supplied from the backlight unit 200 to embody the first image and the second image. A first linear polarizer 310 and a second linear polarizer 320 can be stacked on the backlight unit 200. The transmission axis of the second linear polarizer 320 can be perpendicular to the transmission axis of the first linear polarizer 310. For example, the liquid crystal panel 100 can be positioned between the first linear polarizer 310 and the second linear polarizer 320.

[0035] The backlight unit 200 can include a first light source member 210, a first light guide plate 220, a second light source member 250, and a second light guide plate 260. The first light source member 210 can emit light inside the first light guide plate 220. For example, the first light source member 210 can be positioned on the side of the first light guide plate 220. The second light source member 250 can emit light inside the second light guide plate 260. For example, the second light source member 250 can be positioned on the side of the second light guide plate 260. The second light guide plate 260 can be positioned above the first light guide plate 220. The upper surface of the first light guide plate 220 can extend in the first direction X and the third direction Z. The third direction Z can be perpendicular to the first direction X and the second direction Y. For example, the third direction Z can be the direction FW towards the front window of the automobile in which the display device DP is installed.

[0036] The first light guide plate 220 and the second light guide plate 260 can function as a surface light source. For example, the second light guide plate 260 can overlap with the first light guide plate 220. Thus, in the display device according to an embodiment of the present invention, the light incident on the first light guide plate 220 by the first light source member 210 can be supplied to the liquid crystal panel 100 through the upper surface of the second light guide plate 260. The liquid crystal panel 100 can be positioned above the second light guide plate 260.

[0037] The first light source member 210 can include a plurality of first light source elements 211 and a first circuit board 212. The first light source elements 211 can be mounted on the first circuit board 212. The second light source member 250 can include a plurality of second light source elements 251 and a second circuit board 252. The second light source elements 251 can be mounted on the second circuit board 252.

[0038] The second light source member 250 can be positioned above the first light source member 210 in the second direction Y. For example, the first light source member 210 can be positioned laterally of the first light guide plate 220 facing the first direction X, and the second light source member 250 can be positioned laterally of the second light guide plate 260 facing the first direction X. The first light source member 210 and the second light source member 250 can be independently controlled. For example, the second circuit board 252 can be positioned above the first circuit board 212 in the second direction Y. The second light source elements 251 can be positioned side by side with the first light source elements 211 in the second direction Y.

[0039] The first light source elements 211 can be positioned side by side along one side surface of the first light guide plate 220. The second light source elements 251 can be positioned side by side along one side surface of the second light guide plate 260. For example, the first display region CA of the liquid crystal panel 100 can be positioned close to the first light source elements 211 and the second light source elements 251.

[0040] The backlight unit 200 may further include a reflector 240 positioned on the lower surface of the first light guide plate 220. For example, the first light guide plate 220 may be positioned between the reflector 240 and the second light guide plate 260. The reflector 240 may include a material having a high reflectivity. For example, the reflector 240 may include metals such as aluminum Al and silver Ag. Accordingly, in the display device according to an embodiment of the present invention, the light emitted through the lower surface of the first light guide plate 220 can be reflected by the reflector 240 in the direction of the upper surface of the first light guide plate 220. Therefore, in the display device according to an embodiment of the present invention, the light efficiency can be improved.

[0041] The backlight unit 200 may include a number of optical sheets 230, 270. The optical sheets 230, 270 can make the light emitted through the upper surface of the first light guide plate 220 and the light emitted through the upper surface of the second light guide plate 260 have uniform characteristics. For example, the optical sheets 230, 270 may include a first optical sheet 230 positioned between the first light guide plate 220 and the second light guide plate 260 and a second optical sheet 270 positioned between the second light guide plate 260 and the first linear polarizing plate 310.

[0042] The characteristics of the light emitted through the upper surface of the first light guide plate 220 can be made overall uniform by the first optical sheet 230. For example, the first optical sheet 230 may have a laminated structure of a first diffusion sheet 231 and a first prism sheet 232. The characteristics of the light emitted through the upper surface of the second light guide plate 260 can be made overall uniform by the second optical sheet 270. The second optical sheet 270 may have the same laminated structure as the first optical sheet 230. For example, the second optical sheet 270 may have a laminated structure of a second diffusion sheet 271 and a second prism sheet 272.

[0043] A viewing angle control unit 400 can be positioned between the first light guide plate 220 and the second light guide plate 260 of the backlight unit 200. For example, the viewing angle control unit 400 can be positioned between the first optical sheet 230 and the second light guide plate 260. The viewing angle control unit 400 can partially restrict the traveling direction of the light that has passed through the first optical sheet 230. For example, the viewing angle control unit 400 can include a narrow viewing angle region 401 where the light shielding pattern 430 is located and a wide viewing angle region 402 located outside the light shielding pattern 430.

[0044] The light shielding pattern 430 can include a material capable of blocking light. For example, the light shielding pattern 430 can include a black dye such as carbon black. The light shielding pattern 430 can extend parallel in one side direction.

[0045] That is, in the display device according to an embodiment of the present invention, the traveling path of the light passing through the narrow viewing angle region 401 of the viewing angle control unit 400 can be restricted by the light shielding pattern 430. For example, each light shielding pattern 430 can extend in the third direction Z between the first control substrate 410 and the second control substrate 420. Thereby, in the display device according to an embodiment of the present invention, the viewing angle in the first direction X can be restricted by the narrow viewing angle region 401 of the viewing angle control unit 400. Therefore, in the display device according to an embodiment of the present invention, the image embodied by the light passing through the narrow viewing angle region 401 of the viewing angle control unit 400 may not be recognized by people adjacent in the first direction X. For example, in the display device according to an embodiment of the present invention, the image embodied by the light passing through the narrow viewing angle region 401 may not be recognized by the driver.

[0046] The narrow viewing angle region 401 of the viewing angle control unit 400 can overlap with the first display region CA of the liquid crystal panel 100. For example, in the display device according to an embodiment of the present invention, the first image provided by the first display region CA of the liquid crystal panel 100 can be an image embodied by light passing through the narrow viewing angle region 401 of the viewing angle control unit 400. Thereby, in the display device according to an embodiment of the present invention, an image that is not recognized by the driver sitting in the driver's seat DS can be embodied in the first display region CA of the liquid crystal panel 100. Therefore, in the display device according to an embodiment of the present invention, the dispersion of the driver's line of sight can be prevented.

[0047] The light shielding pattern 430 can be surrounded by a pattern insulating film 440. For example, a pattern insulating film 440 is located between the first control substrate 410 and the second control substrate 420, and each light shielding pattern 430 can cross the pattern insulating film 440 in the third direction Z. Thereby, in the display device according to an embodiment of the present invention, the light emitted through the upper surface of the first light guide plate 220 can pass through the pattern insulating film 440 of the viewing angle control unit 400 and enter the second light guide plate 260. The pattern insulating film 440 can include an insulating material. The pattern insulating film 440 can include a transparent material. The refractive index of the pattern insulating film 440 can be substantially the same as the refractive index of the first control substrate 410 and the refractive index of the second control substrate 420. Therefore, in the display device according to an embodiment of the present invention, the light loss due to the refractive index difference between the first control substrate 410 and the pattern insulating film 440 and the refractive index difference between the pattern insulating film 440 and the second control substrate 420 is minimized.

[0048] The thickness of the pattern insulating film 440 can be the same as the thickness of each light-shielding pattern 430. For example, the second control substrate 420 can be positioned parallel to the first control substrate 410. In the region 401 with a narrow viewing angle, the space between the first control substrate 410 and the second control substrate 420 can be completely filled by the light-shielding pattern 430 and the pattern insulating film 440. Thereby, in the display device according to an embodiment of the present invention, deformation of the viewing angle control unit 400 due to an external impact is prevented. Also, in the display device according to an embodiment of the present invention, distortion of an image due to light passing through the viewing angle control unit 400 can be prevented.

[0049] In the wide viewing angle region 402 of the viewing angle control unit 400, only the first control substrate 410, the second control substrate 420, and the pattern insulating film 440 can be positioned. For example, in the wide viewing angle region 402, the space between the first control substrate 410 and the second control substrate 420 can be completely filled by the pattern insulating film 440. Thereby, in the display device according to an embodiment of the present invention, the traveling path of light passing through the wide viewing angle region 402 of the viewing angle control unit 400 may not be restricted. Therefore, in the display device according to an embodiment of the present invention, an image embodied by light passing through the wide viewing angle region 402 of the viewing angle control unit 400 can be recognized by people around.

[0050] The wide viewing angle region 402 of the viewing angle control unit 400 can overlap with the second display region IA of the liquid crystal panel 100. For example, in the display device according to an embodiment of the present invention, the second image provided by the second display region IA of the liquid crystal panel 100 can be embodied by light passing through the light viewing angle region 402 of the viewing angle control unit 400. Thereby, in the display device according to an embodiment of the present invention, the second image can be recognized by the driver. Therefore, in the display device according to an embodiment of the present invention, the second image can be shared by the driver and the person sitting in the passenger seat.

[0051] The region 402 with the wide viewing angle can be positioned side by side with the region 401 with the narrow viewing angle in the first direction X. The length of the region 402 with the wide viewing angle can be the same as the length of the region 401 with the narrow viewing angle in the first direction X. The region 402 with the wide viewing angle can be in direct contact with the region 401 with the narrow viewing angle. The length of the region 401 with the narrow viewing angle can be the same as the length of the first display area CA in the first direction X. The length of the region 402 with the wide viewing angle can be the same as the length of the second display area IA in the first direction X. For example, the length of the viewing angle control unit 400 can be the same as the length of the liquid crystal panel 100 in the first direction X. The boundary line between the region 401 with the narrow viewing angle and the region 402 with the wide viewing angle can overlap with the boundary line between the first display area CA and the second display area IA. For example, the boundary line between the region 401 with the narrow viewing angle and the region 402 with the wide viewing angle can extend in the third direction Z.

[0052] In the display device according to an embodiment of the present invention, the first image embodied in the first display area CA of the liquid crystal panel 100 can be selectively restricted. For example, the display device according to an embodiment of the present invention can control whether to share the first image using the second light source member 250.

[0053] FIG. 4 is a diagram showing the traveling direction of light in the backlight unit 200 when the viewing angle of the image embodied by the first display area CA of the liquid crystal panel 100 is restricted in the display device according to an embodiment of the present invention. FIG. 5 is a diagram showing the traveling direction of light in the backlight unit 200 when the viewing angle of the image embodied by the first display area CA of the liquid crystal panel 100 is not restricted in the display device according to an embodiment of the present invention.

[0054] Referring to FIGS. 1 to 4, in the display device according to an embodiment of the present invention, when the second light source member 250 does not operate, only the light that has passed through the narrow viewing angle region 401 of the viewing angle control unit 400 is provided to the first display region CA of the liquid crystal panel 100, and only the light that has passed through the wide viewing angle region 402 of the viewing angle control unit 400 is provided to the second display region IA of the liquid crystal panel 100. Accordingly, in the display device according to an embodiment of the present invention, the first image embodied in the first display region CA of the liquid crystal panel 100 is not recognized by the driver, and the second image embodied in the second display region IA of the liquid crystal panel 100 can be shared by the driver and the person sitting in the passenger seat.

[0055] Also, referring to FIGS. 1 to 3 and 5, in the display device according to an embodiment of the present invention, when the second light source member 250 operates, the light that has passed through the narrow viewing angle region 401 of the viewing angle control unit 400 and the light supplied to the second light guide plate 260 by the second light source member 250 are provided to the first display region CA of the liquid crystal panel 100, and the light that has passed through the wide viewing angle region 402 of the viewing angle control unit 400 and the light supplied to the second light guide plate 260 by the second light source member 250 can be provided to the second display region IA of the liquid crystal panel 100. That is, in the display device according to an embodiment of the present invention, when the second light source member 250 operates, light that has not passed through the narrow viewing angle region 401 of the viewing angle control unit 400 can be provided to the first display region CA of the liquid crystal panel 100. Therefore, in the display device according to an embodiment of the present invention, both the first image embodied in the first display region CA and the second image embodied in the second display region IA can be recognized by the driver and the person sitting in the passenger seat. For example, in the display device according to an embodiment of the present invention, when the second light source member 250 operates, one large image shared by the driver and the person sitting in the passenger seat is embodied in the first display region CA and the second display region IA of the liquid crystal panel 100.

[0056] As a result, the display device according to an embodiment of the present invention includes the viewing angle control unit 400 positioned between the first light guide plate 220 and the second light guide plate 260 of the backlight unit 200 and the liquid crystal panel 100 positioned on the second light guide plate 260 of the backlight unit 200. The liquid crystal panel 100 includes a first display area CA and a second display area IA that are arranged side by side in a first direction X. The viewing angle control unit 400 includes a narrow viewing angle area 401 and a wide viewing angle area 402 having the light shielding pattern 430. The narrow viewing angle area 401 of the viewing angle control unit 400 overlaps with the first display area CA of the liquid crystal panel 100, and the wide viewing angle area 402 of the viewing angle control unit 400 can overlap with the second display area IA of the liquid crystal panel 100. Accordingly, in the display device according to an embodiment of the present invention, due to the operation of the second light source member 250 that supplies light to the second light guide plate 260, the first image embodied in the first display area CA of the liquid crystal panel 100 may not be selectively recognized by the driver. That is, in the display device according to an embodiment of the present invention, the viewing angle of the first image embodied in the first display area CA of the liquid crystal panel 100 can be selectively restricted. Therefore, in the display device according to an embodiment of the present invention, the line of sight of people around due to the first image embodied in the first display area CA of the liquid crystal panel 100 can be selectively blocked. For example, in the display device according to an embodiment of the present invention, an accident due to the driver's distracted line of sight can be prevented.

[0057] The display device according to an embodiment of the present invention is described such that the length of the second display area IA is the same as the length of the first display area CA in the first direction X. However, in the display device according to another embodiment of the present invention, the length of the second display area IA may be different from the length of the first display area CA in the first direction X. For example, in the display device according to another embodiment of the present invention, the length of the second display area IA can be smaller than the length of the first display area CA in the first direction X.

[0058] The display device according to an embodiment of the present invention is described as being installed in an automobile. However, the display device according to other embodiments of the present invention can be installed in various devices. For example, the display device according to other embodiments of the present invention can be used for an advertising board or the like that provides a large image to people around. In the display device according to other embodiments of the present invention, it can function as a monitor for correcting and changing an image in which the first display area CA having an area smaller than the second display area IA is embodied. Thereby, in the display device according to other embodiments of the present invention, it is possible to correct and change an image shared with people around without adding a display panel.

[0059] In the display device according to other embodiments of the present invention, the luminance deviation between the first image embodied in the first display area CA of the liquid crystal panel 100 by the light shielding pattern 430 and the second image embodied in the second display area IA of the liquid crystal panel 100 can be alleviated. For example, as shown in FIG. 6, in the display device according to other embodiments of the present invention, the viewing angle control unit 400 of the display device can include a relaxation area 403 located between the narrow viewing angle area 401 and the wide viewing angle area 402. The relaxation area 403 can be in direct contact with the narrow viewing angle area 401 and the wide viewing angle area 402. The relaxation area 403 of the viewing angle control unit 400 can overlap with the boundary line between the first display area CA and the second display area IA. For example, in the display device according to other embodiments of the present invention, the length of the narrow viewing angle area 401 may be smaller than the length of the first display area CA in the first direction X, and the length of the wide viewing angle area 402 may be smaller than the length of the second display area IA in the first direction X.

[0060] At least one dummy pattern 450 can be positioned within the relaxation region 403 of the viewing angle control unit 400. The dummy pattern 450 can include a material capable of blocking light. For example, the dummy pattern 450 can include a black dye such as carbon black. The dummy pattern 450 can include the same material as the light-shielding pattern 430.

[0061] The dummy pattern 450 can have a smaller thickness or shorter length than each light-shielding pattern 430. For example, the thickness 450t of the dummy pattern 450 can be smaller than the vertical distance between the first control substrate 410 and the second control substrate 420. The dummy pattern 450 can be spaced apart from the first control substrate 410 or the second control substrate 420. For example, the dummy pattern 450 can be in contact with the second control substrate 420, and the first control substrate 410 can be spaced apart from the dummy pattern 450. The dummy pattern 450 can extend in the same direction as the light-shielding pattern 430. For example, the dummy pattern 450 can extend in the third direction Z. Thereby, in the display device according to another embodiment of the present invention, the viewing angle of the light incident on the relaxation region 403 can be limited by the dummy pattern 450. The viewing angle of the light passing through the relaxation region 403 can be between the viewing angle of the light passing through the narrow viewing angle region 401 and the viewing angle of the light passing through the wide viewing angle region 402. That is, in the display device according to another embodiment of the present invention, the luminance deviation between the light passing through the narrow viewing angle region 401 and the light passing through the wide viewing angle region 402 can be mitigated by the light passing through the relaxation region 403. Therefore, in the display device according to another embodiment of the present invention, when the first display region CA and the second display region IA embody one large image, the boundary line between the first display region CA and the second display region IA may not be recognized by the user.

[0062] The length of the relaxation region 403 can be smaller than the length of the narrow viewing angle region 401 and the length of the wide viewing angle region 402 in the first direction X. Thereby, in the display device according to another embodiment of the present invention, when the second light source member 250 does not operate, it is possible to prevent the first image embodied in the first display region CA from being recognized by people around due to the relaxation region 403. Therefore, in the display device according to another embodiment of the present invention, it is possible to prevent the line-of-sight dispersion due to the relaxation region 403.

[0063] As shown in FIG. 7, in the display device according to another embodiment of the present invention, a dummy light-shielding layer 460 can be positioned within the wide viewing angle region 402 of the viewing angle control unit 400. The thickness 460t of the dummy light-shielding layer 460 can be smaller than the thickness of each light-shielding pattern 430. For example, the thickness 450t of the dummy light-shielding layer 460 can be smaller than the vertical distance between the first control substrate 410 and the second control substrate 420. For example, the dummy light-shielding layer 460 can be in contact with the second control substrate 420, and the first control substrate 410 can be separated from the dummy light-shielding layer 460. The wide viewing angle region 402 of the second control substrate 420 can be completely covered by the dummy light-shielding layer 460. For example, the length of the dummy light-shielding layer 460 can be the same as the length of the wide viewing angle region 402 in the first direction X. The dummy light-shielding layer 460 can extend in the same direction as the light-shielding pattern 430. For example, the dummy light-shielding layer 460 can extend in the third direction Z.

[0064] The dummy light-shielding layer 460 can include a material capable of reducing the transmitted light. For example, the dummy light-shielding layer 460 can include a black dye such as carbon black. The dummy light-shielding layer 460 can have a thickness smaller than that of the light-shielding pattern 430. The light passing through the dummy light-shielding layer 460 can have substantially the same brightness as the light passing through the narrow viewing angle region 401. The dummy light-shielding layer 460 can include the same material as the light-shielding pattern 430. Thereby, in the display device according to another embodiment of the present invention, the light passing through the wide viewing angle region 402 can have substantially the same hue as the light passing through the narrow viewing angle region 401. That is, in the display device according to another embodiment of the present invention, the hue difference between the image embodied in the first display region CA and the image embodied in the second display region IA can be alleviated by the dummy light-shielding layer 460. Also, in the display device according to another embodiment of the present invention, when a single large image is embodied using the first display region CA and the second display region IA, the user's recognition of the boundary line between the first display region CA and the second display region IA can be alleviated by the dummy light-shielding layer 460. Therefore, in the display device according to another embodiment of the present invention, the quality of the image embodied by the liquid crystal panel 100 can be improved.

[0065] The display device according to an embodiment of the present invention is described such that the first display region CA of the liquid crystal panel 100 is located close to the first light source member 210 and the second light source member 250.

[0066] However, as shown in FIG. 8, in the display device according to another embodiment of the present invention, the first light source member 210 is located on the side of the first light guide plate 220 close to the second display area IA of the liquid crystal panel 100, and the second light source member 250 can be located on the side of the second light guide plate 260 close to the second display area IA of the liquid crystal panel 100. Accordingly, in the display device according to another embodiment of the present invention, the degree of freedom in arranging the first light source member 210 and the second light source member 250 can be improved.

[0067] The display device according to an embodiment of the present invention is described such that the first light source member 210 is located on one side surface of the first light guide plate 220 and the second light source member 250 is located on one side surface of the second light guide plate 260. However, in the display device according to another embodiment of the present invention, the first light source member 210 can be located on at least two side surfaces of the first light guide plate 220, and the second light source member 250 can be located on at least two side surfaces of the second light guide plate 260. For example, in the display device according to another embodiment of the present invention, the first light source member 210 is located on the side of the first light guide plate 220 close to the first display area CA and on the side of the first light guide plate 220 close to the second display area IA, and the second light source member 250 can be located on the side of the second light guide plate 260 close to the first display area CA and on the side of the second light guide plate 260 close to the second display area IA. Accordingly, in the display device according to another embodiment of the present invention, the amount of light supplied to the liquid crystal panel 100 can be increased. Therefore, in the display device according to another embodiment of the present invention, the luminance of the image realized by the liquid crystal panel 100 can be improved.

[0068] The display device according to an embodiment of the present invention is described such that the second light source member 250 is positioned side by side with the first light source member 210 in the second direction Y. However, in the display device according to another embodiment of the present invention, the second light source member 250 can be separated from the first light source member 210 in the first direction X or the third direction Y. For example, in the display device according to another embodiment of the present invention, the first light source member 210 is positioned on the side surface of the first light guide plate 220 close to the first display area CA, and the second light source member 250 can be positioned on the side surface of the second light guide plate 260 close to the second display area IA. Thereby, in the display device according to another embodiment of the present invention, the degree of freedom with respect to the relative positions of the first light source member 210 and the second light source member 250 can be improved. The display device according to an embodiment of the present invention is described such that one viewing angle control unit 400 is positioned between the first light guide plate 220 and the liquid crystal panel 100. However, the display device according to another embodiment of the present invention can include a plurality of viewing angle control units 400. For example, as shown in FIG. 9, in the display device according to another embodiment of the present invention, a first viewing angle control unit 400 is positioned between the first light guide plate 220 and the second light guide plate 260 of the backlight unit 200, and a second viewing angle control unit 500 can be positioned between the second light guide plate 260 of the backlight unit 200 and the liquid crystal panel 100.

[0069] The viewing angle control unit 400 of the first viewing angle can include a narrow viewing angle region where a first light shielding pattern extending in the third direction Z is positioned and a wide viewing angle region positioned outside the first light shielding pattern. The first light shielding pattern can be surrounded by a first pattern insulating film. The first pattern insulating film can extend between the first control substrate and the second control substrate in the wide viewing angle region. For example, the space between the wide viewing angle region of the first control substrate and the wide viewing angle region of the second control substrate can be completely filled by the first pattern insulating film.

[0070] The second viewing angle control unit 500 may include a second light shielding pattern 530 positioned between a third control substrate 510 and a fourth control substrate 520, and a second pattern insulating film 540 surrounding the second light shielding pattern 530. The second light shielding pattern 530 may extend in the first direction X. For example, the second light shielding pattern 530 may extend in a direction perpendicular to the first light shielding pattern. The second light shielding pattern 530 may completely cross the liquid crystal panel 100 in the first direction X. For example, the second light shielding pattern 530 may overlap the first display region and the second display region of the liquid crystal panel 100. Accordingly, in the display device according to another embodiment of the present invention, the viewing angles of light supplied from the backlight unit 200 to the first display region and the second display region of the liquid crystal panel 100 may be restricted by the second viewing angle control unit 500. That is, in the display device according to another embodiment of the present invention, the viewing angle in the third direction Z may be restricted by the second viewing angle control unit 500. For example, the display device according to another embodiment of the present invention may prevent an image embodied by the liquid crystal panel 100 from being reflected by the front window. Therefore, in the display device according to another embodiment of the present invention, accidents due to the dispersion of the line of sight of people around can be effectively prevented.

[0071] According to an embodiment of the present invention, it is described that the thickness of each light-shielding pattern 430 is equal to the vertical distance between the first control substrate 410 and the second control substrate 420. However, in a display device according to another embodiment of the present invention, each light-shielding pattern 430 may be separated from the first control substrate 410 or the second control substrate 420. For example, as shown in FIG. 10, in a display device according to another embodiment of the present invention, the first control substrate 410 may be in contact with the light-shielding pattern 430, and the light-shielding pattern 430 may be separated from the second control substrate 420. The pattern insulating film 440 extends between each light-shielding pattern 430 and the second control substrate 420. The second control substrate 420 may be located between the first control substrate 410 and the liquid crystal panel 100. For example, each light-shielding pattern 430 in the panel insulating film 440 may be disposed close to the light guide plate of the backlight unit. Therefore, a display device according to another embodiment of the present invention can alleviate the luminance deviation between the first image embodied in the first display area CA of the liquid crystal panel 100 by the light-shielding pattern 430 and the second image mounted in the second display area IA of the liquid crystal panel 100. That is, in a display device according to another embodiment of the present invention, the light-shielding pattern 430 is used to prevent accidents due to the dispersion of the line of sight of people around, and the boundary line between the first display area CA and the second display area (IA) may not be recognized by the user.

[0072] In a display device according to another embodiment of the present invention, the dummy pattern 450 in the relaxation region 430 may be located on the same control substrates 410, 420 as the light-shielding pattern 430. For example, as shown in FIG. 11, in a display device according to another embodiment of the present invention, the dummy pattern 450 in the relaxation region 403 may be in direct contact with the first control substrate 410. The second control substrate 420 may be separated from the light-shielding pattern 430 and the dummy pattern 450.

[0073] The dummy pattern 450 may be formed by the same process as the light-shielding pattern 430. Therefore, in a display device according to another embodiment of the present invention, the formation process of the light-shielding pattern 430 and the dummy pattern 450 may be simplified. Therefore, in a display device according to another embodiment of the present invention, the process efficiency can be improved.

[0074] In a display device according to another embodiment of the present invention, the light-shielding layer 460 in the wide viewing angle region 402 may be disposed on the same control substrates 410 and 420 as the light-shielding pattern 430. For example, as shown in FIG. 12, in a display device according to another embodiment of the present invention, the wide viewing angle region 402 of the first control substrate 410 may be covered with the light-shielding layer 460. The light-shielding layer 460 may be in direct contact with the first control substrate 410. For example, the light-shielding layer 460 may be formed simultaneously with the light-shielding pattern 430. Therefore, in a display device according to another embodiment of the present invention, the process efficiency can be improved.

[0075] A display device according to another embodiment of the present invention may include the relaxation pattern 470 located within the wide viewing angle region 401 of the viewing angle control unit 400. For example, as shown in FIG. 13, in a display device according to another embodiment of the present invention, the relaxation pattern 470 may be disposed on the wide viewing angle region 401 of the first control substrate 410. The relaxation patterns 470 may be arranged at regular intervals. For example, the interval between the relaxation patterns 470 may be the same as the interval between the light-shielding patterns 430. The relaxation pattern 470 may be in direct contact with the first control substrate 410. For example, the pattern insulating film 440 may extend between each relaxation pattern 470 and the second control substrate 420. The relaxation pattern 470 may extend parallel in one direction. The relaxation pattern 470 may extend in the same direction as the light-shielding pattern 430. For example, the relaxation pattern 470 may extend in a third direction.

[0076] The relaxation pattern 470 includes a material capable of blocking light. For example, the relaxation pattern 470 may include a black dye such as carbon black. Therefore, in the display device according to another embodiment of the present invention, the luminance of the light passing through the light viewing angle region 402 of the viewing angle control unit 400 can be reduced by the relaxation pattern 470. The relaxation pattern 470 may include the same material as the light shielding pattern 430. For example, the relaxation pattern 470 may be formed simultaneously with the light shielding pattern 430.

[0077] The thickness 470t of each relaxation pattern 470 may be made very thinner than the thickness of the light shielding pattern 430. Therefore, in the display device according to another embodiment of the present invention, the traveling path of the light passing through the light viewing angle region 402 of the viewing angle control unit 400 may not be greatly restricted by the relaxation pattern 470. That is, in the display device according to another embodiment of the present invention, people adjacent to the first direction X may recognize an image realized by the light passing between the relaxation patterns 470. Therefore, in the display device according to another embodiment of the present invention, the viewing angle of the light viewing angle region 402 may be restricted, and the luminance deviation between the light passing through the narrow viewing angle region 401 and the light passing through the light viewing angle region 402 may be alleviated.

[0078] The display device according to an embodiment of the present invention is described assuming that the dummy pattern 450 in the relaxation region 403 has the same thickness. However, in a display device according to another embodiment of the present invention, the dummy patterns 450 having different thicknesses may be arranged in the relaxation region 403. For example, as shown in FIG. 14, in a display device according to another embodiment of the present invention, the dummy pattern 450 may include a first dummy pattern 451, a second dummy pattern 452 having a thickness smaller than that of the first dummy pattern 451, and a third dummy pattern 453 having a thickness thinner than that of the second dummy pattern 452. The first dummy pattern 451 may be arranged near the narrow viewing angle region 401. The third dummy pattern 453 may be arranged close to the wide viewing angle region 402. The second dummy pattern 452 may be located between the first dummy pattern 451 and the third dummy pattern 453. For example, in a display device according to another embodiment of the present invention, the thickness of the dummy pattern 450 may be decreased as going from the narrow viewing angle region 401 toward the wide viewing angle region 402. Therefore, in a display device according to another embodiment of the present invention, the luminance deviation between the light passing through the narrow viewing angle region 401 and the light passing through the light viewing angle region 402 can be effectively relaxed by the dummy pattern 450. Therefore, in a display device according to another embodiment of the present invention, when the first display region CA and the second display region IA of the liquid crystal panel 100 realize one large image, the boundary line between the first display region CA and the second display region IA may not be recognized by the user.

[0079] As shown in FIG. 15, in a display device according to another embodiment of the present invention, dummy patterns 450 having different thicknesses from each other may be arranged in the relaxation region 403, and relaxation patterns 470 in the wide viewing angle region 402 may be arranged. The thickness 470t of each relaxation pattern 470 may be made smaller than the thickness of the third dummy pattern 453. Therefore, in a display according to another embodiment of the present invention, the boundary line between the first display region CA and the second display region IA can be made hardly recognizable by the user.

[0080] In the display device according to another embodiment of the present invention, the light-shielding pattern 430 can be formed in various ways. For example, in the display device according to another embodiment of the present invention, the step of forming the light-shielding pattern 430 may include the step of forming a plurality of trenches in the pattern insulating film 440 and the step of filling the trenches with a light-shielding material. As shown in FIG. 16, in the display device according to another embodiment of the present invention, a base substrate 480 may be disposed between the pattern insulating film 440 and the second control substrate 420. The base substrate 480 may support the pattern insulating film 440 in the step of forming the light-shielding pattern 430. For example, the base substrate 480 may be thicker than the first control substrate 410 and the second control substrate 420. The side surface of each light-shielding pattern 430 may be inclined. For example, the horizontal width of each light-shielding pattern 430 may decrease in the direction from the first control substrate 410 to the second control substrate 420. Therefore, in the display device according to another embodiment of the present invention, the degree of freedom with respect to the step of forming the light-shielding pattern 430 may be improved.

[0081] The display device according to an embodiment of the present invention is described such that the pattern insulating film 440 is located between the first control substrate 410 and the second control substrate 420. However, in the display device according to another embodiment of the present invention, at least one of the first surface of the pattern insulating film 440 facing the light guide plate and the second surface of the pattern insulating film 440 facing the liquid crystal panel 100 may not be covered by the control substrates 410 and 420. For example, as shown in FIG. 17, in the display device according to another embodiment of the present invention, the viewing angle control unit 400 may be composed of the light shielding pattern 430 located above the narrow viewing angle region 401 of the first control substrate 410 and the pattern insulating film 440 surrounding the light shielding pattern 430. The surface of the pattern insulating film 440 facing the liquid crystal panel 100 may be exposed. Therefore, in the display device according to another embodiment of the present invention, the overall size can be reduced. Also, in the display device according to another embodiment of the present invention, a decrease in luminance due to the second control substrate can be prevented. Therefore, in the display device according to another embodiment of the present invention, the degree of freedom in the configuration of the viewing angle control unit 400 can be improved.

Explanation of Reference Numerals

[0082] 100 Liquid crystal panel 200 Backlight unit 220 First light guide plate 260 Second light guide plate 400 Viewing angle control unit 401 Narrow viewing angle region 402 Wide viewing angle region 430 Light shielding pattern 440 Pattern insulating film CA First display region IA Second display region

Claims

1. A backlight unit including a first light guide plate and a second light guide plate located on the first light guide plate, a liquid crystal panel located on the second light guide plate of the backlight unit and including a first display area and a second display area, and a first viewing angle control unit between the first light guide plate and the second light guide plate of the backlight unit, wherein the first viewing angle control unit includes a first light shielding pattern extending in a first direction, the first light shielding pattern is arranged to correspond to the first display area, the first viewing angle control unit further includes a relaxation area overlapping a boundary line between the first display area and the second display area, the relaxation area includes at least one dummy pattern, the dummy pattern has a thickness thinner than that of the first light shielding pattern, a display device.

2. The second display area is in contact with the first display area, and the boundary line between the first display area and the second display area extends in the first direction. The display device according to claim 1.

3. The backlight unit further includes a first light source element located on a side of the first light guide plate and a second light source element located on a side of the second light guide plate. The display device according to claim 1.

4. The backlight unit further includes a first circuit board on which the first light source element is mounted and a second circuit board on which the second light source element is mounted, the second circuit board is separated from the first circuit board in a third direction, the third direction is perpendicular to a plane formed by the first direction and a second direction perpendicular to the first direction. The display device according to claim 3.

5. The second light source element is positioned side by side with the first light source element in a third direction perpendicular to a plane formed by the first direction and a second direction perpendicular to the first direction. The display device according to claim 3.

6. The first display area of the liquid crystal panel is located near the first light source element and the second light source element. The display device according to claim 5.

7. The backlight unit further includes a second viewing angle control unit located between the second light guide plate of the backlight unit and the liquid crystal panel, wherein the second viewing angle control unit includes a second light shielding pattern extending in a second direction. The display device according to claim 1.

8. The display device according to claim 7, wherein the second light-shielding pattern overlaps with the first display region and the second display region of the liquid crystal panel.

9. The display device according to claim 1, wherein the dummy pattern extends in the first direction.

10. A first light source element located on one side of the first light guide plate, A second light guide plate located above the first light guide plate and overlapping with the first light guide plate, A viewing angle control unit located between the first light guide plate and the second light guide plate, including a narrow viewing angle region where the light-shielding pattern is located and a wide viewing angle region located outside the light-shielding pattern, A liquid crystal panel located above the second light guide plate, including a first display region and a second display region, and A second light source element located on one side of the second light guide plate, The narrow viewing angle region of the viewing angle control unit overlaps with the first display region of the liquid crystal panel, The wide viewing angle region of the viewing angle control unit overlaps with the second display region of the liquid crystal panel, The viewing angle control unit includes a dummy light-shielding layer corresponding to the wide viewing angle region, The dummy light-shielding layer has a thickness smaller than that of the light-shielding pattern, The dummy light-shielding layer extends in the first direction and the second direction within the wide viewing angle region, A display device.

11. The light-shielding pattern extends in the first direction, The second display region is located side by side with the first display region in the second direction perpendicular to the first direction, The display device according to claim 10, wherein the length of the narrow viewing angle region in the second direction is the same as the length of the wide viewing angle region in the second direction.

12. The display device according to claim 10, wherein the dummy light-shielding layer includes the same material as the light-shielding pattern.

13. The display device according to claim 10, wherein the amount of light transmitted through the space between the light-shielding patterns of the viewing angle control unit is substantially the same as the amount of light transmitted through the dummy light-shielding layer.

Images