CN111308778B - Backlight unit and display device including the same - Google Patents

Abstract

Embodiments of the present disclosure relate to a backlight unit and a display device including the same. In an embodiment, a backlight unit includes a light emitting device and a lower reflector on a substrate. The lower reflector has a hole to receive the light emitting device and to expose the light emitting device. The lower reflector may have a height greater than a height of the light emitting device. The backlight unit may include a colored resin in the hole and on the light emitting device. The backlight unit may include an optical path modulator above the light emitting device and on the colored resin. The optical path modulator may have a refractive index different from that of the colored resin to reflect the emitted light toward the lower reflector at a boundary of the optical path modulator and the colored resin.

Description

Backlight unit and display device including backlight unit

Cross References to Related Applications

This application claims the benefit of Korean Patent Application No. 10-2018-0159467 filed on December 11, 2018 and Korean Patent Application No. 10-2019-0134625 filed on October 28, 2019, which was adopted by This reference is incorporated herein for all purposes as if fully set forth herein.

technical field

Embodiments disclosed herein relate to a backlight unit and a display device including the backlight unit.

Background technique

A liquid crystal display (LCD) is one of flat panel displays for displaying images using liquid crystals. LCDs are widely used throughout the industry due to their advantages such as thin thickness, light weight, and low power consumption. The LCD is capable of displaying images by adjusting the transmittance of light emitted from a backlight unit according to its property of controlling transmittance by changing the alignment of liquid crystals. Such an LCD uses a light emitting diode (LED), a cold cathode fluorescent lamp (CCFL), a hot cathode fluorescent lamp (HCLF), or the like as a light source of a backlight unit. In recent years, light emitting diodes having excellent light efficiency and high color reproducibility have been widely used as light sources for backlight units.

The backlight unit may be classified into an edge type or a direct type according to an arrangement of light sources and a light transmission form. In the direct type backlight unit, a light source such as an LED may be disposed on the rear side of the display device.

A light source device used in such a direct type backlight unit may include light emitting diodes and a substrate on which the light emitting diodes are mounted and which includes circuit elements for driving the light emitting diodes and the like. In addition, a phosphor film including an expensive phosphor may be provided on the light emitting diode so that light emitted from the light emitting device is excited to exhibit a color. However, since a large amount of phosphor is used in the phosphor film, the manufacturing cost of the backlight unit may increase. In addition, when the light emitted from the light emitting device is not sufficiently excited, color reproducibility deteriorates.

Contents of the invention

Embodiments of the present disclosure provide a backlight unit having high color reproducibility and a display device including the same.

In addition, embodiments of the present disclosure provide a backlight unit capable of reducing manufacturing costs and a display device including the same.

According to the embodiments of the present disclosure, a backlight unit having high color reproducibility and a display device including the same can be provided.

According to the embodiments of the present disclosure, it is possible to provide a backlight unit capable of reducing manufacturing costs and a display device including the backlight unit.

In various embodiments, the backlight unit includes: a substrate; a light emitting device on the substrate; a lower reflector on the substrate, the lower reflector having a hole for accommodating and exposing the light emitting device, the lower reflector having a height higher than that of the light emitting device a large height and configured to reflect light emitted from the light emitting device; a colored resin in the hole and on the light emitting device, the colored resin having a height lower than that of the lower reflector; and above the light emitting device and at An optical path modulator on a colored resin having a different refractive index from that of the colored resin to reflect emitted light toward the lower reflector at a boundary between the optical path modulator and the colored resin.

In an embodiment, the colored resin includes a plurality of phosphors having at least two different colors. In an embodiment, the colored resin has an upper surface that is concave or convex.

In an embodiment, the optical path modulator comprises air.

In an embodiment, the backlight unit further comprises a distributed Bragg reflector on the light emitting device, the distributed Bragg reflector being in the hole and between the substrate and the optical path modulator.

In an embodiment, the backlight unit further includes: an adhesive film on the lower reflector and the optical path modulator; and a light modifying sheet on the adhesive film, the light modifying sheet comprising a plurality of light modifying patterns, the plurality of At least one of the light modifying patterns at least partially overlaps the light emitting device and has one or more layers including a top layer on a surface of the light modifying sheet facing the substrate, An air gap exists between the one or more layers and the adhesive film.

In an embodiment, the one or more layers further comprise an intermediate layer on a surface of the top layer facing the substrate, the top layer having dimensions larger than the dimensions of the intermediate layer.

In an embodiment, the one or more layers further comprise an underlayer on the substrate-facing surface of the intermediate layer, the underlayer having a size smaller than that of the intermediate layer.

In an embodiment, the backlight unit further includes: a phosphor film on the light modifying sheet; a diffuser plate on the phosphor film; and an optical sheet on the diffuser plate.

In various embodiments, a backlight unit includes: a substrate including a groove having sidewalls coated with a reflective material and having a first height; a light emitting device in the groove having a height higher than the first height a low second height; a colored resin in the groove and on the light emitting device, the colored resin having a third height lower than the first height; and an optical path modulator in the groove and on the colored resin, the optical path modulator having a different refractive index from that of the colored resin to reflect light emitted from the light emitting device toward a sidewall of the groove at a boundary of the optical path modulator and the colored resin.

In various embodiments, a method for manufacturing a backlight unit includes: disposing a plurality of light emitting devices in a region of a substrate; disposing a lower reflector on the substrate, wherein a hole of the lower reflector accommodates and exposes A plurality of light-emitting devices, the holes have a depth greater than the height of the plurality of light-emitting devices; curing the colored resin in the holes, the cured resin has a height lower than the depth; setting an optical path modulation in the holes and on the colored resin The optical path modulator has a refractive index different from that of the colored resin.

In an embodiment, the method further includes: disposing a reflector on the plurality of light emitting devices; and coating the substrate with a reflective material.

In an embodiment, the method further includes: disposing an adhesive film on the lower reflector and the optical path modulator; A plurality of light-modifying patterns stacked, at least one of the plurality of light-modifying patterns having one or more layers, the one or more layers comprising Top layer, an air gap exists between the one or more layers and the adhesive film.

In an embodiment, the method further comprises printing a top layer on the surface of the light modifying sheet.

In an embodiment, the method further comprises printing an intermediate layer of said one or more layers on a top layer, the top layer having an area larger than the area of the intermediate layer, wherein after disposing the light modifying sheet on the adhesive film The light-modifying sheet with the printed top and middle layers was inverted prior to application.

In an embodiment, the method further includes printing a bottom layer of the one or more layers on the middle layer, the bottom layer having a smaller area than the middle layer.

In various embodiments, the backlight unit includes: a light emitting device having a flip chip structure; a first reflector disposed to surround a first area including the light emitting device and a periphery of the light emitting device; a colored resin; an adhesive film disposed over the colored resin to be spaced a predetermined distance from the colored resin; and a light modifying sheet disposed on the adhesive film, the light modifying sheet including a Light modifies the pattern.

In an embodiment, the backlight unit further includes: a material disposed between the adhesive film and the colored resin, the material having a different refractive index from that of the colored resin.

In an embodiment, the first reflector has a height higher than that of the colored resin.

In an embodiment, the backlight unit further includes: a substrate including a groove corresponding to the first region, and wherein the reflective film is applied to the substrate.

In an embodiment, the backlight unit further includes: a phosphor film disposed over the light modifying sheet, the phosphor film including a phosphor having a color different from that of the colored resin.

In an embodiment, the colored resin includes two types of phosphors having different colors.

In an embodiment, the backlight unit further includes a second reflector disposed on an upper surface of the light emitting device.

In various embodiments, a display device includes: a liquid crystal panel; and a backlight unit disposed under the liquid crystal panel and configured to radiate light toward the liquid crystal panel. The backlight unit includes: a light emitting device having a flip chip structure; a first reflector disposed to surround a first region including the light emitting device and a periphery of the light emitting device; a colored resin disposed in the first region; an adhesive a film disposed over the colored resin to be spaced a predetermined distance from the colored resin; and a light modifying sheet disposed on the adhesive film, the light modifying sheet including a light modifying pattern disposed corresponding to a position of the light emitting device.

Description of drawings

The above and other aspects, features and advantages of the present disclosure will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a structural diagram illustrating a display device according to an embodiment of the present disclosure.

FIG. 2 is a view illustrating an example of a structure of a backlight unit included in a display device according to an embodiment of the present disclosure.

3A to 3E are views each showing an example of a specific structure of the backlight unit shown in FIG. 2 .

FIG. 4 is a view illustrating a structure of a backlight unit according to an embodiment of the present disclosure.

5A and 5B are views illustrating examples of structures according to positions of light modification patterns included in the backlight unit illustrated in FIG. 4 .

FIG. 6 is a structural view showing an embodiment of the backlight unit shown in FIG. 1 .

FIG. 7 is a perspective view showing a reflector employed in the backlight unit shown in FIG. 1 .

FIG. 8 is a conceptual diagram illustrating a path of light emitted from a light emitting device.

9A to 9F are conceptual views illustrating a process of manufacturing the backlight unit shown in FIG. 6 .

FIG. 10 is a structural view showing an embodiment of the backlight unit shown in FIG. 1 .

FIG. 11 is a structural view showing an embodiment of the backlight unit shown in FIG. 1 .

Detailed ways

The advantages and features of the present disclosure and a method of achieving the advantages and features of the present disclosure will become apparent by referring to the embodiments of the present disclosure described in detail below with reference to the accompanying drawings. However, the present disclosure is not limited to the embodiments set forth below, but can be implemented in various forms. The following embodiments are provided only to fully disclose the present disclosure and to inform those skilled in the art of the scope of the present disclosure, and the present disclosure is limited only by the scope of the appended claims.

The shapes, dimensions, ratios, angles, numbers, etc. shown in the drawings for explaining the embodiments of the present disclosure are exemplary, and thus the present disclosure is not limited to the shown contents. Throughout the specification, the same or similar reference numerals denote the same or similar elements. Also, in the description of the present disclosure, when it is determined that a detailed description of a related well-known technology unnecessarily makes the subject matter of the present disclosure unclear, the detailed description will be omitted. When the expression "comprises", "has", "comprises" etc. as mentioned herein is used, any other components may be added unless the expression "only" is used. When an element is expressed in the singular, the element may encompass plural forms unless the element is explicitly specifically mentioned.

Furthermore, when explaining elements in the embodiments of the present disclosure, elements in the embodiments of the present disclosure should be construed as covering a tolerance range even if no explicit indication is given individually.

Also, terms such as first, second, A, B, (a), (b), etc. may be used herein when describing components of the present disclosure. Each of these terms is not used to define the nature, sequence or order of the corresponding component, but is only used to distinguish the corresponding component from one or more other components. When it is described that a certain structural element is "connected to", "coupled to" or "in contact with" another structural element, it should be interpreted that another structural element can be "connected to", "coupled to" "The structural element is either "in contact with" the structural element and a structural element is directly connected to or in direct contact with another structural element. When using terms such as "on", "above", "below", "beside", etc. to describe the positional relationship of two parts, unless terms such as "only" or " directly", otherwise one or more other components may be positioned between the two components.

In addition, components in the embodiments of the present disclosure are not limited by these terms. These terms are only used to distinguish one component from another. Therefore, when a constituent element is hereinafter referred to as a first constituent element, the constituent element may be a second constituent element within the technical concept of the present disclosure.

In addition, the features (components) in the embodiments of the present disclosure may be partially or completely coupled or combined with each other, or may be partially or completely separated from each other, and may be technically interlocked and driven in various ways, and each embodiment can be implemented independently of each other or can be implemented in combination with each other.

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

FIG. 1 is a structural diagram illustrating a display device according to an embodiment of the present disclosure.

Referring to FIG. 1 , the display device 10 may include a display panel 100 such as a liquid crystal panel, and a backlight unit 200 configured to radiate light to the display panel 100 .

The display panel 100 may be a liquid crystal panel. The liquid crystal panel may include: a liquid crystal layer capable of generating a difference in transmittance according to an arrangement of liquid crystal molecules; a pixel electrode configured to selectively apply a voltage to the liquid crystal layer; and a common electrode configured to apply a common voltage to liquid crystal layer. The liquid crystal layer may be disposed between the pixel electrode and the common electrode, and an arrangement of liquid crystal molecules may be determined according to a voltage applied between the pixel electrode and the common electrode. In addition, the display panel 100 may include color filters. In addition, the display panel 100 may further include: a pixel circuit configured to selectively apply a voltage to the pixel electrode; and a driving circuit configured to supply a signal and a voltage to the pixel circuit.

The backlight unit 200 is disposed under the display panel 100 and may uniformly radiate light toward at least a portion or the entire surface of the display panel 100 from under the display panel 100 . The backlight unit 200 may generate and radiate light using light emitting diodes. The backlight unit 200 may be spaced apart from the display panel 100 by a predetermined distance d1.

FIG. 2 is a view illustrating an example of a structure of a backlight unit included in a display device according to an embodiment of the present disclosure.

Referring to FIG. 2 , the display device 10 according to an embodiment of the present disclosure may include: a display panel 100 ; and a backlight unit 200 disposed under the display panel 100 and configured to provide light to the display panel 100 .

Various structures may be provided between the backlight unit 200 and the display panel 100 . For example, the display panel 100 may be fixed to the backlight unit 200 via the guide plate 400, the foam pad 500, etc., but the present disclosure is not limited thereto.

The backlight unit 200 may include a cover bottom 300 configured to accommodate optical elements and the like constituting the backlight unit 200 .

A substrate 210 may be disposed on the cover bottom 300 and a plurality of light emitting devices 211 may be disposed on the substrate 210 . The light emitting device 211 may be, for example, a light emitting diode (LED) or may be a mini LED or a micro LED. In addition, the light emitting device 211 may be arranged in a form in which the chip type light emitting device 211 is mounted on the substrate 210, so that the thickness of the backlight unit 200 may be reduced and also a light source having a wide radiation angle and high optical efficiency may be provided. The light emitting device 211 configured to be mounted on the substrate 210 may be referred to as a light emitting device 211 having a flip chip structure.

The light emitting device 211 may emit light in a white wavelength band, or in some cases, the light emitting device 211 may emit light in a specific wavelength band (eg, a blue wavelength band). The substrate 210 may be a printed circuit board, and the reflector 212 may be disposed on at least a portion of a region of the substrate 210 where the light emitting device 211 is not disposed. The light source protection unit 205 may be disposed on the plurality of light emitting devices 211 and the reflector 212 . The light source protection unit 205 may protect the plurality of light emitting devices 211 and may provide a function of diffusing light emitted from the light emitting devices 211 . The light source protection unit 205 may be a resin layer containing resin.

A light modifying sheet 216 may be provided on the light source protection unit 205 . The light modifying sheet 216 may include a plurality of light modifying patterns 216p disposed on a face facing the light emitting device 211 . Here, a plurality of light modification patterns 216 p may be disposed at positions corresponding to the plurality of light emitting devices 211 on the lower surface of the light modification sheet 216 . The light modifying pattern 216p may transmit a part of light emitted from the light emitting device. Light modifying sheet 216 may be a light control sheet capable of transmitting a portion of light. The light modifying sheet can scatter, reflect, diffract, or transmit light emitted from the light emitting device 211 , thereby improving the image quality of the backlight unit 200 .

That is, by arranging the light modifying pattern 216p in a region where the intensity of light emitted from the light emitting device 211 is the highest, the difference between the region where the light emitting device 211 is provided (the region having a larger amount of light) and the area between the light emitting device 211 can be reduced. The brightness deviation between the regions in between (areas with a smaller amount of light).

Light modifying patch 216 may include a light modifying material. In addition, the light modifying pattern 216p may include titanium dioxide (TiO ₂ ). Additionally, the light modifying material may be white. However, it is not limited to this.

A diffuser plate 218 configured to diffuse light incident from below may be provided on the light modifying sheet 216 . In addition, a phosphor film 217 or one or more optical sheets 219 may be disposed on the diffusion plate 218 . When the light incident on the phosphor film 217 is blue light, the light passing through the phosphor film 217 may be converted into white light.

3A to 3E are views each showing an example of a specific structure of the backlight unit shown in FIG. 2 .

Referring to FIG. 3A , a plurality of light emitting devices 211 may be disposed on a substrate 210 . A reflective film coated on the substrate 210 may be provided. The applied reflective film may be formed of white pigment. That is, white pigment may be applied to the substrate 210 .

Referring to FIG. 3B , the reflector 212 may be disposed on at least a portion of an area other than the area on the substrate 210 where the light emitting device 211 is disposed.

The reflector 212 may be disposed in a shape in which a region corresponding to the light emitting device 211 is an opening, and the reflector 212 may be disposed on the substrate 210 . The reflector 212 can reflect the light emitted from the light emitting device 211 to the front side of the backlight unit (facing the display panel 100 ), thereby improving the optical efficiency of the backlight unit.

Here, when the light emitting device 211 is provided in the form of a chip, the height of the reflector 212 may be greater than that of the light emitting device 211 due to the small size of the light emitting device 211 .

Accordingly, light emitted in a lateral direction of the light emitting device 211 can be reflected by the sides of the opening in the reflector 212 and can be emitted to the front of the backlight unit 200 , thereby further improving the optical efficiency of the backlight unit 200 .

Referring to FIG. 3C , a light source protection unit 205 may be disposed on a plurality of light emitting devices 211 and reflectors 212 . The light source protection unit 205 may contain, for example, resin. When the light source protection unit 205 includes resin, the light source protection unit 205 may be provided by providing a partition outside the substrate 210 or outside a region where the plurality of light emitting devices 211 are disposed and applying resin to the inside of the partition. The light source protection unit 205 functions to protect the plurality of light emitting devices 211 disposed on the substrate 210 and may provide the function of a light guide plate by diffusing light emitted from the light emitting devices 211 . Light emitted from the light emitting device 211 may more uniformly travel through the light source protection unit 205 to the upper surface of the light source protection unit 205 . At this time, even if the reflector 212 modifies or adjusts the direction in which light propagates through the light source protection unit 205 or the like, the intensity of light emitted in the vertical direction of the light emitting device 211 may be high, and thus the uniformity of the image may deteriorate.

According to an embodiment of the present disclosure, by disposing the light modifying pattern 216p having optical characteristics such as scattering, reflection, diffraction, and transmission at a position corresponding to the light emitting device 211 on the light source protection unit 205, the backlight unit 200 can be reduced in size. Improve the uniformity of the image while increasing the thickness.

Referring to FIG. 3D , a light modification sheet 216 may be disposed on the light source protection unit 205 , and a plurality of light modification patterns 216 p may be disposed on a lower surface of the light modification sheet 216 . However, the present disclosure is not limited thereto, and a plurality of light modifying patterns 216 p may be disposed on the upper surface of the light modifying sheet 216 . The light modifying sheet 216 may then be bonded to the light source protection unit 205 by a piece of adhesive film 215 . The adhesive film 215 may be an OCA film. The light modifying sheet 216 may be made of, for example, PET or the like, but is not limited thereto. Each of the plurality of light modifying patterns 216p disposed on the lower surface or the upper surface of the light modifying sheet 216 may be arranged to correspond to one of the plurality of light emitting devices 211 disposed on the substrate 210 . For example, the light modification pattern 216p may be disposed to at least partially overlap the light emitting device 211 in consideration of light diffusion characteristics, and the light modification pattern 216p may be disposed to overlap a region including a region where the light emitting device 211 is disposed. The light modifying pattern 216p may scatter, reflect, diffract, or transmit light emitted from the light emitting device 211 . For example, the light modifying pattern 216p may scatter light emitted from the light emitting device 211 such that light can be emitted from the light modifying sheet 216 . In addition, the light modification pattern 216p may reflect the light emitted from the light emitting device 211 in the vertical direction and may cause the light to be reflected by the reflector 212 again so that the light is emitted to an area between the light emitting devices 211 or between the light modification patterns 216p. Area.

As described above, the light emitted from the light emitting device 211 may be scattered, reflected, diffracted or transmitted through the light modifying pattern 216p, and the image quality of the backlight unit 200 may be improved.

Referring to FIG. 3E , a diffuser plate 218 may be disposed on the light modifying sheet 216 , and a phosphor film 217 may be disposed on the diffuser plate 218 . Then, at least one optical sheet 219 may be disposed on the phosphor film 217 . Here, positions where the diffusion plate 218 and the phosphor film 217 are disposed may be exchanged with each other. The diffuser plate 218 may diffuse light emitted through the light modifying sheet 216 .

The phosphor film 217 may include phosphors having a specific color, and may excite incident light to emit light in a specific wavelength band. Accordingly, light passing through the phosphor film 217 may have a specific color of the phosphor included in the phosphor film 217 or a color mixed with the specific color. For example, in the case where the light emitting device 211 emits light in a first wavelength band (eg, blue light), the phosphor film 217 may emit light in a second wavelength band in response to light incident on the phosphor film 217. (eg, green light) and light in a third wavelength band (eg, red light).

In some cases, the phosphor film 217 may be disposed in a partial area on the diffusion plate 218 . For example, when the light emitting device 211 emits light in the blue wavelength band, the phosphor film 217 may be provided only in a region other than a region corresponding to a region in the liquid crystal panel 100 where the blue sub-pixel SP is arranged. That is, light that does not pass through the phosphor film 217 may be made to reach the blue sub-pixel SP of the liquid crystal panel 100 . In addition, the phosphor film 217 may not be provided in the backlight unit 200 . For example, in the case where the light emitting device 211 emits light in the white wavelength band or its emitting surface is coated with a color conversion film that emits light in the green wavelength band and light in the red wavelength band, it is not necessary to set Phosphor film 217 .

As described above, the embodiment can improve the image quality of the backlight unit while reducing the thickness of the backlight unit by providing the light-modifying sheet 216 including the light-modifying pattern 216p provided in conjunction with the light-emitting device 211 and various optical elements. corresponding position of the component.

Hereinafter, the embodiment will be described with a specific example of the light modifying pattern 216 p provided on the light modifying sheet 216 .

FIG. 4 is a view illustrating a structure of a backlight unit according to an embodiment of the present disclosure.

Referring to FIG. 4 , a substrate 210 may be disposed on a cover bottom 300 and the substrate 210 may be bonded to the cover bottom 300 by an adhesive tape 210 a disposed between the cover bottom 300 and the substrate 210 .

A plurality of light emitting devices 211 may be disposed on the substrate 210, and a reflector 212 may be disposed on at least a portion of an area other than the area on the substrate 210 where the light emitting devices 211 are disposed.

Here, each of the light emitting devices 211 may be, for example, an LED and may include a light emitting portion 211a including an n-type semiconductor layer, an active layer, and a p-type semiconductor layer, and an electrode portion 211b. A light source protection unit 205 is disposed on the plurality of light emitting devices 211 and the reflector 212 . A light modification sheet 216 may be provided on the light source protection unit 205 , and a light modification pattern 216 p is provided at a position corresponding to the light emitting device 211 on the light modification sheet 216 . Then, a diffuser plate 218 , a phosphor film 217 , an optical sheet 219 , etc. may be disposed on the light modifying sheet 216 .

The light-modifying pattern 216p disposed on the lower surface of the light-modifying sheet 216 may be realized by printing a substance having light-modifying properties on the light-modifying sheet 216 . For example, the light-modifying pattern 216p may be provided by printing an ink containing titanium dioxide (TiO ₂ ) on the light-modifying sheet 216 . In addition, the light modifying pattern 216p provided on the lower surface of the light modifying sheet 216 may be arranged in one layer or may be arranged in a multilayer structure. That is, as shown in FIG. 4, the light modifying pattern 216p provided on the lower surface of the light modifying sheet 216 may be configured in three layers. The light-modifying pattern 216p can be realized by printing the light-modifying substance on the light-modifying sheet 216 three times, and the area where the light-modifying substance is to be printed can be gradually narrowed. Then, the light modifying pattern 216p may be disposed on the light emitting device 211 by inverting the light modifying sheet 216 on which the light modifying pattern 216p is disposed and arranging the light modifying sheet 216 on the light source protection unit 205 .

Accordingly, the area of the light-modifying patterns 216p may taper away from the bottom of the light-modifying sheet 216, and the central portion of each light-modifying pattern 216p may be thicker than the outer (peripheral) portion thereof.

That is, since the intensity of light emitted from the light emitting device 211 in a vertical direction is greater than that in an oblique or lateral direction, a central portion of the light modification pattern 216p may be configured thicker than other portions. However, the embodiments are not limited thereto.

By disposing the light modifying pattern 216p on the light emitting device 211 as described above, it is possible to prevent or reduce the light emission in the area where the light emitting device 211 is provided by scattering, reflecting, diffracting or blocking at least a part of the light emitted from the light emitting device 211 in the vertical direction. hotspots appear. The light modifying sheet 216 on which the light modifying pattern 216 p is provided may be bonded to the light source protection unit 205 via the adhesive film 215 . At this time, the adhesive film 215 may be disposed in at least a portion of a region other than the region where the light modifying pattern 216p is disposed on the lower surface of the light modifying sheet 216 .

Accordingly, the adhesive film 215 may not be disposed in a region where the light modification pattern 216p is disposed, and an air gap may exist between the light modification pattern 216p and the light source protection unit 205 . In addition, sides of the light modifying pattern 216p and sides of the adhesive film 215 may be spaced apart from each other. Since there is an air gap between the light modifying pattern 216p and the light source protection unit 205 , light emitted in a lateral direction of the light modifying pattern 216p may be reflected by the air gap through the light modifying sheet 216 and toward the display panel 100 . That is, light emitted in a lateral direction of the light modifying pattern 216p may be emitted at a large refraction angle by the air gap having a low refractive index or may be reflected by the air gap. Since the light reflected by the air gap is emitted after being reflected again by the reflector 212, optical efficiency may be improved while assisting the light modifying function of the light modifying pattern 216p.

As described above, through the structure in which the light modifying pattern 216p and the air gap are arranged at positions corresponding to the light emitting devices 211, it is possible to improve the optical efficiency of the backlight unit while preventing or mitigating hot spots. In addition, the light modifying pattern 216p disposed on the lower surface of the light modifying sheet 216 may be arranged in different structures depending on the position where the light modifying pattern 216p is disposed.

5A and 5B are views illustrating examples of structures according to positions of light modification patterns included in the backlight unit illustrated in FIG. 4 .

Referring to FIG. 5A , there are shown examples of luminance appearing through the backlight unit according to the structure of the light modification pattern 216p, wherein EX1 shows an example of the luminance measured when the light modification pattern 216p is arranged in a constant structure, and EX2 represents when the light modification pattern 216p is arranged in a constant structure. An example of measured luminance when the light-modifying pattern 216p is arranged in a different configuration depending on the position of the light-modifying pattern 216p.

As shown in EX1 in FIG. 5A, when the structure of the light modification pattern 216pa provided in the outer region of the backlight unit 200 and the structure of the light modification pattern 216pd provided in the central region are the same (for example, the same thickness or size) , the brightness of an outer (peripheral) area of the backlight unit may be lower than that of a central area of the backlight unit.

That is, since in the outer area of the backlight unit, when the light modifying pattern 216p having the same level of light modifying characteristics is provided, the number of light emitting devices 211 providing light to the corresponding area is relatively small compared with the central area, the backlight The brightness in the outer area of the unit may decrease compared to the central area of the backlight unit.

Therefore, as shown in EX2 in FIG. 5A, by arranging the light modification pattern 216pa provided in the outer area of the backlight unit 200 and the light modification pattern 216pd provided in the central area of the backlight unit 200 to have different structures, it is possible to The brightness deterioration of the outer area of the backlight unit 200 is prevented and the overall brightness is made more uniform.

As an example, the light modification pattern 216p may be arranged such that the thickness T1 of the light modification pattern 216pa disposed in the outer region of the backlight unit 200 is smaller than the thickness T2 of the light modification pattern 216pd disposed in the central region.

Alternatively, the light modifying pattern 216p may be arranged such that the area W1 of the thickest portion in the light modifying pattern 216pb disposed adjacent to the outer area of the backlight unit is smaller than the area W2 of the thickest portion in the light modifying pattern 216pd. That is, in the light modifying patterns 216pa and 216pb disposed in an outer region of the backlight unit 200 or in a region adjacent to the outer region, the region of a portion having a higher blocking characteristic is made smaller.

In addition, the light modification pattern 216p may be arranged such that the thickness of the light modification pattern 216p gradually decreases from the central area of the backlight unit 200 toward the outer area of the backlight unit 200, or such that the area of the thickest part of the light modification pattern 216p gradually decreases. Small. That is, in the light modifying patterns 216pa and 216pb disposed in or adjacent to the outer region of the backlight unit 200, the region of the portion having a high blocking characteristic is made smaller.

In addition, the thickness of the light modification pattern 216p gradually decreases from the central area of the backlight unit 200 to the outer area of the backlight unit 200, or the area of the thickest part of the light modification pattern 216p is from the central area of the backlight unit 200 to the outer area of the backlight unit 200. The area gradually decreases.

Also, in some cases, the light modifying patterns 216p may be variously arranged such that the number or interval of the light emitting devices 211 is different between the central area and the outer area of the backlight unit 200 .

Referring to FIG. 5B , another example of a structure in which a light modifying pattern 216p is provided on the lower surface of the light modifying sheet 216 is shown.

Here, the distance between the light emitting devices 211 disposed in the outer area of the backlight unit 200 may be smaller than the distance between the light emitting devices 211 disposed in the central area of the backlight unit 200 . That is, the light emitting devices 211 may be arranged in a structure in which the light emitting devices 211 are denser in the outer area of the backlight unit 200 so that the luminance becomes uniform in the central area and the outer area of the backlight unit 200 set up.

In addition, since the light-modifying patterns 216p provided on the lower surface of the light-modifying sheet 216 are arranged to correspond to the light emitting devices 211, the interval between the light-modifying patterns 216p provided in the outer area of the backlight unit 200 may be different from that provided at The intervals between the light modifying patterns 216p in the central area of the backlight unit 200 are different.

As an example, an interval D1 in the first direction of the light modification patterns 216p disposed in the outer area of the backlight unit 200 may be smaller than an interval D2 in the first direction of the light modification patterns 216p disposed in the central area of the backlight unit 200 . In addition, an interval D3 in the second direction of the light modification patterns 216p disposed in the outer area of the backlight unit 200 may be smaller than an interval D4 in the second direction of the light modification patterns 216p disposed in the central area of the backlight unit 200 .

The size, thickness, etc. of the light modification pattern 216p disposed in the outer area of the backlight unit 200 may be different from the size, thickness, etc. of the light modification pattern 216p disposed in the central area of the backlight unit 200 .

For example, as shown in FIG. 5B , the size S1 of the light modification patterns 216pe and 216pf disposed in the outer area of the backlight unit 200 may be smaller than the size S2 of the light modification pattern 216pg disposed in the central area of the backlight unit 200 .

Alternatively, the light modifying pattern 216p may have a multilayer structure as described above. In this case, the thickness of the light modification patterns 216pe and 216pf provided in the outer area of the backlight unit 200 or the area of the portion having the maximum thickness among the light modification patterns 216pe and 216pf may be smaller than those provided in the central area of the backlight unit 200, respectively. The thickness of the light modifying pattern 216pg in or the region of the portion having the largest thickness in the light modifying pattern 216pg.

That is, by reducing the size of the light modification patterns 216pe and 216pf disposed in the outer region of the backlight unit 200, the light modification patterns 216pe and 216pf may be disposed to correspond to the light emitting devices 211 arranged at small intervals. Accordingly, generation of hot spots at locations corresponding to the light emitting devices 211 in the outer region of the backlight unit 200 may be prevented or mitigated.

Also, by reducing the level at which light emitted from the light emitting device 211 is scattered, reflected, diffracted or blocked in the outer area of the backlight unit 200, the amount of light to be emitted increases and the brightness of the outer area of the backlight unit 200 improves. Therefore, the entire area of the backlight unit 200 can be made to exhibit more uniform brightness.

As described above, by arranging the light modifying patterns 216p to have different structures in different regions in the backlight unit 200, it is possible to prevent or mitigate reduction in luminance in outer regions of the backlight unit 200 and improve uniformity of luminance.

In addition, through the structure in which the above-described modification pattern 216p is provided, it is possible to prevent or alleviate hot spots of the backlight unit 200 and improve uniformity of luminance.

Embodiments can also provide a method of improving the image quality of the backlight unit 200 while increasing the optical efficiency of the backlight unit by diffracting light emitted in the vertical direction of the light emitting device 211 .

6 is a structural view showing an embodiment of the backlight unit shown in FIG. 1 , and FIG. 7 is a perspective view showing a reflector employed in the backlight unit shown in FIG. 1 .

6 and 7, the backlight unit 200a may include: a substrate 210; a light emitting device 211 disposed on the substrate 210, the light emitting device 211 having a flip-chip structure; a reflector 212 disposed to surround the light emitting device 211 and include a light emitting a first region 1AR of the periphery of the device; a colored resin 213 disposed in the first region 1AR; an adhesive film 215 disposed over the colored resin 213 to be spaced apart from the colored resin 213 by a predetermined distance; and a light modifying sheet 216, The light modifying sheet 216 is disposed on the adhesive film 215 and has a light modifying pattern 216p disposed corresponding to the position of the light emitting device 211 .

The light emitting device 211 may have a flip chip structure. The light emitting device 211 may emit blue light. However, the color of light emitted by the light emitting device 211 is not limited thereto. The light emitting device 211 may be disposed at the center of the first region 1AR on the substrate 210 .

The reflector 212 may reflect light emitted from the light emitting device 211 . The reflector 212 may be disposed on the substrate 210 . The reflector 212 may include a hole corresponding to the first area 1AR, as shown in FIG. 7 . When the reflector 212 is disposed on the substrate 210, the first region 1AR on the substrate 210 may be exposed to correspond to the hole. In addition, the substrate 210 may reflect light. The substrate 210 may include a reflective material. The substrate 210 and the reflector 212 may be coated with white pigment to reflect light. The white pigment may include photo solder resist (PSR). However, the present disclosure is not limited thereto. Here, the shape of the hole corresponding to the first region 1AR is shown as a circle, but is not limited thereto.

The colored resin 213 may be disposed in the first region 1AR. Due to the holes, the colored resin 213 may be disposed only in the first region 1AR. The colored resin 213 can be cured by ultraviolet rays. After the colored resin 213 is disposed in the first region 1AR, the colored resin 213 may be cured using ultraviolet rays. The colored resin 213 may include red phosphor. Light passing through the colored resin 213 may be purple. However, the present disclosure is not limited thereto. Since the colored resin 213 is provided only in the first region 1AR, it is possible to reduce the usage amount of the phosphor, thereby reducing the manufacturing cost.

An adhesive film 215 may be disposed on the colored resin 213 . The adhesive film 215 may contain resin. The refractive index of the adhesive film 215 may be the same as or similar to that of the colored resin 213 . However, the present disclosure is not limited thereto. The adhesive film 215 may be disposed to be spaced apart from the colored resin 213 by a predetermined distance. That is, the optical path modulator 214 having a refractive index different from that of the colored resin 213 may be provided between the adhesive film 215 and the colored resin 213 . The optical path modulator 214 may be any suitable material having a different refractive index from that of the colored resin 213 . The optical path modulator 214 and the colored resin 213 may be in contact with each other so that light may undergo total internal reflection at the boundary between the optical path modulator 214 and the colored resin 213 . An angle at which light is totally reflected may correspond to a difference in refractive index between the optical path modulator 214 and the colored resin 213 . Optical path modulator 214 may be a material having a refractive index ranging from 1 to 1.46. The optical path modulator 214 can be air. However, the present disclosure is not limited thereto.

The light modifying patch 216 may include a light modifying pattern 216p. The light modification sheet 216 may be disposed on the adhesive film 215 such that the light modification pattern 216 p is disposed at a position corresponding to the light emitting device 211 . Generation of hot spots may be prevented or mitigated by scattering, reflecting, diffracting, or blocking light emitted from the light emitting device in a vertical direction by the light modifying pattern 216p. The light modifying pattern 216p may reflect incident light.

A phosphor film 217 may be disposed on the light modifying sheet 216 . The color of the phosphor included in the phosphor film 217 may be different from that of the phosphor included in the colored resin 213 . A diffusion plate 218 may be disposed on the phosphor film 217 , and an optical sheet 219 may be disposed on the diffusion plate 218 . The number of optical sheets 219 is shown as one, but is not limited thereto.

In an embodiment, a reflector 212 a may also be disposed above the light emitting device 211 . The reflector 212a disposed above the light emitting device 211 may be a distributed Bragg reflector. However, the present disclosure is not limited thereto. Light emitted from the light emitting device 211 and having a path in a vertical direction or in a direction close to the vertical direction may be reflected by the reflector 212a.

FIG. 8 is a conceptual diagram illustrating a path of light emitted from a light emitting device.

Referring to FIG. 8 , a light emitting device 211 may be disposed in a colored resin 213 . Accordingly, when the light emitted from the light emitting device 211 passes through the colored resin 213 , the light emitted from the light emitting device 211 may be excited to have energy corresponding to a color mixed with a phosphor included in the colored resin 213 . For example, when the light emitting device 211 emits blue light and the colored resin 213 includes a red phosphor, light passing through the colored resin 213 may have a purple color. However, depending on the path of light, there may be differences in the degree of color mixing. For example, since the thickness of the colored resin 213 through which the light beams of the first group A among the light beams emitted from the light emitting device 211 passes is small, the colors cannot be sufficiently mixed. However, among the light beams emitted from the light emitting device 211 , the light beams corresponding to the second group B pass through the colored resin 213 and are reflected by the reflector 212 . Then, the light beam passes through the colored resin 213 again and then proceeds toward the display panel 100 . Therefore, the light beams of the first group A and the light beams of the second group B may differ in color reproducibility. In addition, a problem arises in that the color reproducibility of the backlight unit 200a is deteriorated by the light beams of the first group A. Referring to FIG.

In order to solve the above problem, when at least some of the light beams of the first group A undergo total internal reflection at the boundary of the colored resin 213 so that its path is changed, the light beams emitted from the light emitting device 211 may be included in the third group C middle. The light beams of the third group C are reflected at the upper boundary of the colored resin 213, are then directed to the colored resin 213 toward the reflector 212 (or substrate 210), and are then reflected by the reflector 212 (or substrate 210) to toward The display panel 100 radiates. This can enhance color reproducibility of the backlight unit 200a.

In order to cause total internal reflection at the boundary of the colored resin 213, a material having a different refractive index from that of the colored resin 213 (for example, the optical path modulator 214 shown in FIG. 6) may be provided on the colored resin 213. In addition, it is also possible to increase the angle θ1 at which total internal reflection occurs at the boundary of the colored resin 213 by providing a large difference in refractive index between the colored resin 213 and the material provided on the colored resin 213, which makes it possible to increase the The amount of light undergoing total internal reflection at the boundary of the resin 213 .

9A to 9F are conceptual views illustrating a process of manufacturing the backlight unit shown in FIG. 6 .

As shown in FIG. 9A , in a backlight unit 200 a, a light emitting device 211 may be disposed on a substrate 210 . Each light emitting device 211 may have a flip chip structure directly connected to the substrate 210 . The light emitting devices 211 may be arranged to correspond to the first region 1AR on the substrate 210 . Each light emitting device 211 may be disposed at the center of one of the first regions 1AR. Here, although the number of light emitting devices 211 disposed on the substrate 210 is shown as three, the present disclosure is not limited thereto. The substrate 210 may include a reflective material to reflect light. In addition, the substrate 210 may be coated with a white pigment. In addition, each light emitting device 211 may also be provided with a reflector 212 a on the light emitting device 211 , as shown in FIG. 6 . The reflector 212a disposed on the light emitting device 211 may be a distributed Bragg reflector.

As shown in FIG. 9B , a reflector 212 may be provided on a substrate 210 . The reflector 212 may include a hole having a predetermined diameter, and the hole may correspond to the first region 1AR. Accordingly, the first region 1AR on the substrate 210 may not be covered by the reflector 212 .

In addition, as shown in FIG. 9C , the colored resin 213 is put into the first region 1AR corresponding to the hole of the reflector 212, and the colored resin 213 is cured by ultraviolet rays. The upper surface of the colored resin 213 may be disposed below the upper surface of the reflector 212 . That is, the height h2 of the reflector 212 may be higher than the height h1 of the colored resin 213 . Here, although the upper surface of the colored resin 213 is shown parallel to the horizontal plane, the present disclosure is not limited thereto, and the upper surface of the colored resin 213 may be concave or convex. However, the highest point of the upper surface of the colored resin 213 is lower than the height of the reflector 212 .

Then, as shown in FIG. 9D , an adhesive film 215 may be disposed over the substrate 210 on which the reflector 212 is disposed. Since the height of the reflector 212 is higher than that of the colored resin 213 , the adhesive film 215 may be disposed such that the adhesive film 215 is disposed above the colored resin 213 to form a predetermined gap above the colored resin 213 . The optical path modulator 214 may be disposed in a predetermined gap. The optical path modulator 214 can be air. However, the optical path modulator 214 is not limited thereto, and may be any material as long as the material has a different refractive index from that of the colored resin 213 . The adhesive film 215 may be a light-transmitting material.

In addition, as shown in FIG. 9E , a light modifying sheet 216 may be provided on the adhesive film 215 . The light modifying sheet 216 may include a light modifying pattern 216p, and the light modifying pattern 216p may be disposed at a position corresponding to a position where the light emitting device 211 is disposed. The light modifying pattern 216p included in the light modifying sheet 216 is capable of reflecting, scattering, diffracting or blocking light emitted from the light emitting device 211 in a vertical direction or light emitted from the light emitting device 211 at an angle close to the vertical direction, thereby preventing or The generation of hot spots in the backlight unit 200 shown in FIG. 1 is mitigated.

Additionally, a phosphor film 217 may be disposed on the light modifying sheet 216 as shown in FIG. 9F . The phosphor film 217 may include a phosphor having a color different from that of the colored resin. A diffusion plate 218 may be disposed on the phosphor film 217 , and an optical sheet 219 may be disposed on the diffusion plate 218 .

FIG. 10 is a structural view showing an embodiment of the backlight unit shown in FIG. 1 .

Referring to FIG. 10, the backlight unit 200b may include: a substrate 210; a light emitting device 211 disposed on the substrate 210, the light emitting device 211 having a flip-chip structure; The first region 1AR; the colored resin 213 provided in the first region 1AR; the adhesive film 215 provided at a predetermined distance from the colored resin 213; and the light modifying sheet 216 provided on the adhesive film 215 , the light modifying sheet 216 has a light modifying pattern 216p arranged to correspond to the position of the light emitting device 211 .

The light emitting device 211 may emit blue light. However, the present disclosure is not limited thereto. The light emitting device 211 may be disposed at the center of the first region 1AR on the substrate 210 .

The reflector 212 may reflect light emitted from the light emitting device 211 . The reflector 212 may be disposed on the substrate 210 . The reflector 212 may be the same as the reflector 212 shown in FIG. 3 and may include a hole corresponding to the first region 1AR. When the reflector 212 is disposed on the substrate 210, the first region 1AR on the substrate 210 may be exposed to correspond to the hole. The reflector 212 may be coated with white paint to reflect light. The white pigment may include photo solder resist (PSR). However, the present disclosure is not limited thereto. Here, the shape of the hole corresponding to the first region 1AR is shown as a circle, but is not limited thereto.

The colored resin 213 may be disposed in the first region 1AR. Due to the hole, the colored resin 213 may be provided only in the first region 1AR (and in other regions exposed through other holes formed by the reflector 212 ). The colored resin 213 can be cured by ultraviolet rays. After the colored resin 213 is disposed in the first region 1AR, the colored resin 213 may be cured using ultraviolet rays. The colored resin 213 may include yellow phosphor. In addition, the colored resin 213 may include red phosphors and green phosphors. Light passing through the colored resin 213 may be purple. However, the present disclosure is not limited thereto. Since the colored resin 213 is disposed only in the first region 1AR (instead of a larger region on the substrate 210 ), the amount of phosphor used can be reduced, thereby reducing manufacturing costs.

An adhesive film 215 may be disposed on the colored resin 213 . The adhesive film 215 may contain resin. The refractive index of the adhesive film 215 may be the same as or similar to that of the colored resin 213 . However, the present disclosure is not limited thereto. The adhesive film 215 may be an OCA film. The adhesive film 215 may be disposed to be spaced apart from the colored resin 213 by a predetermined distance. That is, the optical path modulator 214 having a refractive index different from that of the colored resin 213 may be provided between the adhesive film 215 and the colored resin 213 . The optical path modulator 214 and the colored resin 213 may be in contact with each other so that light may undergo total internal reflection at the boundary between the optical path modulator 214 and the colored resin 213 . The angle at which light undergoes total internal reflection may correspond to the difference in refractive index between the optical path modulator 214 and the colored resin 213 . The optical path modulator 214 can be air. However, the present disclosure is not limited thereto.

The light modifying patch 216 may include a light modifying pattern 216p. The light modification sheet 216 may be disposed on the adhesive film 215 such that the light modification pattern 216 p is disposed at a position corresponding to the light emitting device 211 . Generation of hot spots in the backlight unit 200b may be prevented or mitigated by reflecting, scattering, diffracting or blocking light emitted from the light emitting device and having a path in a vertical direction or a path close to a vertical direction by the light modifying pattern 216p. The light modification pattern 216p may have the same shape as the light modification pattern shown in FIG. 4 .

A diffuser plate 218 may be disposed on the light modifying sheet 216 and an optical sheet 219 may be disposed on the diffuser plate 218 . The number of optical sheets 219 is shown as one, but is not limited thereto.

Therefore, unlike the backlight unit shown in FIG. 2, the colored resin 213 may include two phosphors with different colors or may include phosphors with two colors, so that the backlight unit may not include a phosphor film over the light modifying sheet. 217. This makes it possible to reduce the amount of phosphor used in the backlight unit 200, thereby reducing manufacturing costs.

FIG. 11 is a structural view showing an embodiment of the backlight unit shown in FIG. 1 .

Referring to FIG. 11, the backlight unit 200c may include: a substrate 210; a light emitting device 211 having a flip-chip structure disposed on the substrate 210; a reflector 212 disposed to surround the light emitting device 211 and a first light-emitting device including a periphery of the light emitting device. Region 1AR; colored resin 213 disposed in first region 1AR; adhesive film 215 disposed over colored resin 213 to be spaced apart from colored resin 213 by a predetermined distance; and light modification disposed on adhesive film 215 The sheet 216 , the light modifying sheet 216 has a light modifying pattern 216p arranged to correspond to the position of the light emitting device 211 .

The light emitting device 211 may have a flip chip structure. In the flip chip structure, the light emitting device 211 is directly disposed on the substrate 210 rather than being mounted in a package, thereby making it possible to manufacture a light source that is lightweight and has a large radiation angle. The light emitting device 211 may emit blue light. However, the present disclosure is not limited thereto. The light emitting device 211 may be disposed at the center of the first region 1AR on the substrate 210 .

Grooves CA corresponding to the first region 1AR may be provided in the substrate 210 . The light emitting device 211 may be disposed in the groove CA. The outer walls of the slot CA may serve as reflectors. In order for the outer wall of the groove CA to function as a reflector, a white pigment may be applied to the substrate 210 . That is, the reflector may include the substrate 210 and white paint applied to the substrate. The white pigment may contain photo solder resist (PSR). However, the present disclosure is not limited thereto. Here, the groove CA corresponding to the first region 1AR may have a circular shape, but is not limited thereto.

The colored resin 213 may be disposed in the first region 1AR. Due to the groove CA, the colored resin 213 may be disposed only in the first region 1AR (and disposed in other regions exposed through other grooves of the substrate 210 ). The colored resin 213 can be cured by ultraviolet rays. After the colored resin 213 is disposed in the first region 1AR, the colored resin 213 may be cured using ultraviolet rays. The colored resin 213 may include red phosphor. However, the colored resin 213 is not limited thereto and may include a yellow phosphor. In addition, the colored resin 213 may include red phosphors and green phosphors. Light passing through the colored resin 213 may be purple. However, the present disclosure is not limited thereto. Since the colored resin 213 is provided only in the first region 1AR, the usage amount of the phosphor can be reduced.

An adhesive film 215 may be disposed on the colored resin 213 . The adhesive film 215 may contain resin. The refractive index of the adhesive film 215 may be the same as or similar to that of the colored resin 213 . However, the present disclosure is not limited thereto. The adhesive film 215 may be an OCA film. The adhesive film 215 may be disposed to be spaced apart from the colored resin 213 by a predetermined distance. That is, the optical path modulator 214 having a refractive index different from that of the colored resin 213 may be provided between the adhesive film 215 and the colored resin 213 . The optical path modulator 214 and the colored resin 213 may be in contact with each other so that light may undergo total internal reflection at the boundary between the optical path modulator 214 and the colored resin 213 . The angle at which light undergoes total internal reflection may correspond to the difference in refractive index between the optical path modulator 214 and the colored resin 213 . Optical path modulator 214 may be a material having a refractive index ranging from 1 to 1.46. The optical path modulator can be air. However, the present disclosure is not limited thereto.

The light modifying patch 216 may include a light modifying pattern 216p. The light modification sheet 216 may be disposed on the adhesive film 215 such that the light modification pattern 216 p is disposed at a position corresponding to the light emitting device 211 . Generation of hot spots in the backlight unit 200c may be prevented or mitigated by reflecting, scattering, diffracting or blocking light emitted from the light emitting device and having a path in a vertical direction or a path close to a vertical direction by the light modifying pattern 216p. The light modification pattern 216p may have the same shape as the light modification pattern shown in FIG. 4 . However, the present disclosure is not limited thereto.

A phosphor film 217 may be disposed on the light modifying sheet 216 . The phosphor film 217 may include green phosphor. However, the present disclosure is not limited thereto. In addition, when the colored resin 213 includes yellow phosphors or red and green phosphors, the phosphor film 217 may not be provided on the light modifying sheet 216 .

A diffuser plate 218 may be disposed on the light modifying sheet 216 or phosphor film 217 , and an optical sheet 219 may be disposed on the diffuser plate 218 . The number of optical sheets 219 is shown as one, but is not limited thereto.

The above description and drawings provide examples of the technical concept of the present disclosure for illustrative purposes only. It will be understood by those skilled in the art to which the present disclosure pertains that various modifications and changes can be made in forms such as combination, separation, replacement, and changes in configurations without departing from the essential characteristics of the present disclosure. Therefore, the embodiments disclosed in the present disclosure are intended to illustrate the scope of the technical idea of the present disclosure, and the scope of the present disclosure is not limited by the embodiments. The scope of the present disclosure should be interpreted based on the appended claims in such a manner that all technical ideas included within the scope equivalent to the claims belong to the present disclosure.

In addition, embodiments of the present disclosure also include:

Embodiment (1). A backlight unit, comprising:

Substrate;

a light emitting device on said substrate;

A lower reflector on the substrate, the lower reflector has a hole for accommodating and exposing the light emitting device, the lower reflector has a height greater than that of the light emitting device and is configured to reflect light from the light emitting device light emitted by the light emitting device;

a colored resin in the hole and on the light emitting device, the colored resin having a height lower than that of the lower reflector; and

An optical path modulator above the light emitting device and on the colored resin, the optical path modulator having a refractive index different from that of the colored resin, so that the optical path modulator and the colored resin The boundaries of the resin reflect the emitted light towards the lower reflector.

Embodiment (2). The backlight unit according to embodiment (1), wherein the colored resin includes a plurality of phosphors having at least two different colors.

Embodiment (3). The backlight unit according to embodiment (1), wherein the colored resin has an upper surface that is concave or convex.

Embodiment (4). The backlight unit according to embodiment (1), wherein the optical path modulator includes air.

Embodiment (5). The backlight unit according to embodiment (1), further comprising:

A distributed Bragg reflector on the light emitting device, the distributed Bragg reflector in the hole and between the substrate and the optical path modulator.

Embodiment (6). The backlight unit according to embodiment (1), further comprising:

an adhesive film on the lower reflector and the optical path modulator; and

A light modifying sheet on the adhesive film, the light modifying sheet comprising a plurality of light modifying patterns at least partially overlapping a plurality of light emitting devices, the plurality of light modifying patterns having one or more layers , the one or more layers comprising a top layer on the surface of the light modifying sheet facing the substrate, an air gap between the one or more layers and the adhesive film .

Embodiment (7). The backlight unit according to embodiment (1), further comprising:

an adhesive film on the lower reflector and the optical path modulator; and

A light modifying sheet on the adhesive film, the light modifying sheet comprising a plurality of light modifying patterns, at least one of the plurality of light modifying patterns at least partially overlapping the light emitting device and having a or more layers, the one or more layers comprising a top layer on the surface of the light modifying sheet facing the substrate, between the one or more layers and the adhesive film There is an air gap in between.

Embodiment (8). The backlight unit according to embodiment (6), wherein the one or more layers further comprise:

An intermediate layer on a surface of the top layer facing the substrate, the top layer having a size larger than that of the intermediate layer.

Embodiment (9). The backlight unit according to embodiment (8), wherein the one or more layers further comprise:

An underlayer on a surface of the intermediate layer facing the substrate, the underlayer having a size smaller than that of the intermediate layer.

Embodiment (10). The backlight unit according to embodiment (6), wherein a central portion of at least one of the plurality of light modifying patterns is configured to be thicker than other portions.

Embodiment (11). The backlight unit according to embodiment (6), further comprising:

a phosphor film on said light modifying sheet;

a diffuser plate on the phosphor film; and

Optical sheets on the diffuser plate.

Embodiment (12). A backlight unit, comprising:

a substrate comprising a trench having sidewalls coated with a reflective material and having a first height;

a light emitting device in the groove, the light emitting device having a second height lower than the first height;

a colored resin in the groove and on the light emitting device, the colored resin having a third height lower than the first height; and

an optical path modulator in the groove and on the colored resin, the optical path modulator having a refractive index different from that of the colored resin so as to be at a boundary between the optical path modulator and the colored resin reflect light emitted from the light emitting device toward the sidewall of the groove.

Embodiment (13). The backlight unit according to embodiment (12), wherein the colored resin includes a plurality of phosphors having at least two different colors.

Embodiment (14). The backlight unit according to embodiment (12), wherein the colored resin has an upper surface that is concave or convex.

Embodiment (15). The backlight unit according to embodiment (12), wherein the optical path modulator includes air.

Embodiment (16). The backlight unit according to embodiment (12), further comprising:

A distributed Bragg reflector on the light emitting device, the distributed Bragg reflector in the groove and between the substrate and the optical path modulator.

Embodiment (17). A method for manufacturing a backlight unit, the method comprising:

arranging a plurality of light emitting devices in the area of the substrate;

A lower reflector is disposed on the substrate, wherein a hole of the lower reflector accommodates and exposes the plurality of light emitting devices, the hole has a depth greater than a height of the plurality of light emitting devices;

curing the colored resin in the hole, the cured resin having a height lower than the depth; and

An optical path modulator is provided in the hole and on the colored resin, the optical path modulator having a different refractive index than that of the colored resin.

Embodiment (18). The method according to embodiment (17), further comprising:

disposing a reflector on the plurality of light emitting devices; and

The substrate is coated with a reflective material.

Embodiment (19). The method according to embodiment (17), further comprising:

providing an adhesive film on the lower reflector and the optical path modulator; and

A light-modifying sheet is provided on the adhesive film, the light-modifying sheet includes a plurality of light-modifying patterns respectively at least partially overlapping the plurality of light-emitting devices, the plurality of light-modifying patterns having one or more a plurality of layers, the one or more layers including a top layer on the surface of the light modifying sheet facing the substrate, between the one or more layers and the adhesive film There is an air gap.

Embodiment (20). The method according to embodiment (17), further comprising:

providing an adhesive film on the lower reflector and the optical path modulator; and

A light-modifying sheet is provided on the adhesive film, the light-modifying sheet includes a plurality of light-modifying patterns respectively at least partially overlapping the plurality of light-emitting devices, at least one of the plurality of light-modifying patterns - having one or more layers including a top layer on the surface of the light modifying sheet facing the substrate, between the one or more layers and the adhesive There are air gaps between the mixture films.

Embodiment (21). The method according to embodiment (19), further comprising:

The top layer is printed on the surface of the light modifying sheet.

Embodiment (22). The method according to embodiment (21), further comprising:

Printing an intermediate layer of the one or more layers on the top layer, the top layer having an area larger than the area of the intermediate layer, wherein after disposing the light modifying sheet on the adhesive The light-modifying sheet was inverted with the printed top and middle layers prior to film application.

Embodiment (23). The method according to embodiment (22), further comprising:

A bottom layer of the one or more layers is printed on the middle layer, the bottom layer having an area smaller than that of the middle layer.

Embodiment (24). A backlight unit, comprising:

A light emitting device having a flip-chip structure;

a first reflector disposed to surround a first region including the light emitting device and a periphery of the light emitting device;

a colored resin disposed in the first region;

an adhesive film disposed over the colored resin to be spaced a predetermined distance from the colored resin; and

A light modifying patch disposed on the adhesive film, the light modifying patch comprising a light modifying pattern disposed to correspond to a location of the light emitting device.

Embodiment (25). The backlight unit according to embodiment (24), further comprising:

A material disposed between the adhesive film and the colored resin, the material having a different refractive index from that of the colored resin.

Embodiment (26). The backlight unit according to embodiment (24), wherein the first reflector has a height higher than that of the colored resin.

Embodiment (27). The backlight unit according to embodiment (24), further comprising: a substrate including a groove corresponding to the first region, and wherein a reflective film is applied to the substrate.

Embodiment (28). The backlight unit according to embodiment (24), further comprising:

A phosphor film disposed over the light modifying sheet, the phosphor film including a phosphor having a color different from that of the colored resin.

Embodiment (29). The backlight unit according to embodiment (24), wherein the colored resin includes two types of phosphors having different colors.

Embodiment (30). The backlight unit according to embodiment (24), further comprising:

A second reflector disposed on the upper surface of the light emitting device.

Embodiment (31). The backlight unit according to embodiment (24), wherein a thickness of the light modifying pattern gradually decreases from a central area of the backlight unit to an outer area of the backlight unit.

Embodiment (32). The backlight unit according to embodiment (24), wherein the light modifying pattern is configured to have different structures in different regions in the backlight unit.

Embodiment (33). A display device comprising:

display panel;

a backlight unit disposed under the display panel, the backlight unit configured to radiate light toward the display panel;

Wherein, the backlight unit includes:

A light emitting device having a flip-chip structure;

a first reflector disposed to surround a first region including the light emitting device and a periphery of the light emitting device;

a colored resin disposed in the first region;

an adhesive film disposed over the colored resin to be spaced a predetermined distance from the colored resin; and

A light modifying patch disposed on the adhesive film, the light modifying patch comprising a light modifying pattern disposed to correspond to a location of the light emitting device.

Embodiment (34). The display device according to embodiment (33), further comprising:

A material disposed between the adhesive film and the colored resin, the material having a different refractive index from that of the colored resin.

Embodiment (35). The display device according to embodiment (33), wherein the first reflector has a height higher than that of the colored resin.

Embodiment (36). The display device according to embodiment (33), wherein the backlight unit further includes: a substrate including grooves corresponding to the first region, and wherein the reflective film is covered by applied to the substrate.

Embodiment (37). The display device according to embodiment (33), further comprising:

A phosphor film disposed over the light modifying sheet, the phosphor film including a phosphor having a color different from that of the colored resin.

Embodiment (38). The display device according to embodiment (33), wherein the colored resin includes two types of phosphors having different colors.

Embodiment (39). The display device according to embodiment (33), further comprising:

A second reflector disposed on the upper surface of the light emitting device.

Claims (39)

1. A backlight unit, comprising: Substrate; a light emitting device on said substrate; A lower reflector on the substrate, the lower reflector has a hole for accommodating and exposing the light emitting device, the lower reflector has a height greater than that of the light emitting device and is configured to reflect light from the light emitting device light emitted by the light emitting device; a colored resin in the hole and on the light emitting device, the colored resin having a height lower than that of the lower reflector; an optical path modulator above the light emitting device and on the colored resin, the optical path modulator having a different refractive index compared with that of the colored resin so as to separate the optical path modulator and the colored resin reflecting the emitted light towards the lower reflector at the boundary of ; an adhesive film on the lower reflector and the optical path modulator; and a light modifying patch on said adhesive film, said light modifying patch comprising a plurality of light modifying patterns, Wherein, the optical path modulator is located in the hole and surrounded by the colored resin, the lower reflector and the adhesive film. 2. The backlight unit according to claim 1, wherein the colored resin comprises a plurality of phosphors having at least two different colors. 3. The backlight unit according to claim 1, wherein the colored resin has an upper surface that is concave or convex. 4. The backlight unit of claim 1, wherein the optical path modulator comprises air. 5. The backlight unit according to claim 1, further comprising: A distributed Bragg reflector on the light emitting device, the distributed Bragg reflector in the hole and between the substrate and the optical path modulator. 6. The backlight unit according to claim 1, wherein the plurality of light modifying patterns at least partially overlap a plurality of light emitting devices, the plurality of light modifying patterns have one or more layers, the one One or more layers comprising a top layer on the surface of the light modifying patch facing the substrate, an air gap exists between the one or more layers and the adhesive film. 7. The backlight unit according to claim 1, further comprising: an adhesive film on the lower reflector and the optical path modulator; and A light modifying sheet on the adhesive film, the light modifying sheet comprising a plurality of light modifying patterns, at least one of the plurality of light modifying patterns at least partially overlapping the light emitting device and having a or more layers, the one or more layers comprising a top layer on the surface of the light modifying sheet facing the substrate, between the one or more layers and the adhesive film There is an air gap in between. 8. The backlight unit according to claim 6, wherein the one or more layers further comprise: An intermediate layer on a surface of the top layer facing the substrate, the top layer having a size larger than that of the intermediate layer. 9. The backlight unit according to claim 8, wherein the one or more layers further comprise: An underlayer on a surface of the intermediate layer facing the substrate, the underlayer having a size smaller than that of the intermediate layer. 10. The backlight unit according to claim 6, wherein a central portion of at least one of the plurality of light modifying patterns is configured to be thicker than other portions. 11. The backlight unit according to claim 6, further comprising: a phosphor film on said light modifying sheet; a diffuser plate on the phosphor film; and Optical sheets on the diffuser plate. 12. A backlight unit comprising: a substrate comprising a trench having sidewalls coated with a reflective material and having a first height; a light emitting device in the groove, the light emitting device having a second height lower than the first height; a colored resin in the groove and on the light emitting device, the colored resin having a third height lower than the first height; an optical path modulator in the groove and on the colored resin, the optical path modulator having a refractive index different from that of the colored resin so as to be at a boundary between the optical path modulator and the colored resin reflecting light emitted from the light emitting device toward the sidewall of the groove; an adhesive film on the optical path modulator; and a light modifying patch on said adhesive film, said light modifying patch comprising a plurality of light modifying patterns, Wherein, the optical path modulator is located in the groove and surrounded by the colored resin, the side wall and the adhesive film. 13. The backlight unit of claim 12, wherein the colored resin comprises a plurality of phosphors having at least two different colors. 14. The backlight unit according to claim 12, wherein the colored resin has an upper surface which is concave or convex. 15. The backlight unit of claim 12, wherein the optical path modulator comprises air. 16. The backlight unit according to claim 12, further comprising: A distributed Bragg reflector on the light emitting device, the distributed Bragg reflector in the groove and between the substrate and the optical path modulator. 17. A method for manufacturing a backlight unit, the method comprising: arranging a plurality of light emitting devices in the area of the substrate; A lower reflector is disposed on the substrate, wherein a hole of the lower reflector accommodates and exposes the plurality of light emitting devices, the hole has a depth greater than a height of the plurality of light emitting devices; curing the colored resin in the hole, the cured resin having a height less than the depth; disposing an optical path modulator in the hole and on the colored resin, the optical path modulator having a different refractive index than that of the colored resin; providing an adhesive film on the lower reflector and the optical path modulator; and disposing a light-modifying patch on the adhesive film, the light-modifying patch comprising a plurality of light-modifying patterns, Wherein, the optical path modulator is located in at least one of the holes and is surrounded by the colored resin, the lower reflector and the adhesive film. 18. The method of claim 17, further comprising: disposing a reflector on the plurality of light emitting devices; and The substrate is coated with a reflective material. 19. The method of claim 17, wherein the plurality of light modifying patterns at least partially overlap the plurality of light emitting devices, the plurality of light modifying patterns having one or more layers, the plurality of light modifying patterns having one or more layers, the One or more layers include a top layer on the surface of the light modifying patch facing the substrate, an air gap between the one or more layers and the adhesive film. 20. The method of claim 17, further comprising: providing an adhesive film on the lower reflector and the optical path modulator; and A light-modifying sheet is provided on the adhesive film, the light-modifying sheet includes a plurality of light-modifying patterns respectively at least partially overlapping the plurality of light-emitting devices, at least one of the plurality of light-modifying patterns - having one or more layers including a top layer on the surface of the light modifying sheet facing the substrate, between the one or more layers and the adhesive There are air gaps between the mixture films. 21. The method of claim 19, further comprising: The top layer is printed on the surface of the light modifying sheet. 22. The method of claim 21, further comprising: Printing an intermediate layer of the one or more layers on the top layer, the top layer having an area larger than the area of the intermediate layer, wherein after disposing the light modifying sheet on the adhesive The light-modifying sheet was inverted with the printed top and middle layers prior to film application. 23. The method of claim 22, further comprising: A bottom layer of the one or more layers is printed on the middle layer, the bottom layer having an area smaller than that of the middle layer. 24. A backlight unit comprising: A light emitting device having a flip-chip structure; a first reflector disposed to surround a first region including the light emitting device and a periphery of the light emitting device; a colored resin disposed in the first region; an adhesive film disposed over the colored resin to be spaced apart from the colored resin by a predetermined distance; an optical path modulator above the light emitting device and on the colored resin; and a light modifying patch disposed on said adhesive film, said light modifying patch comprising a light modifying pattern arranged to correspond to a position of said light emitting device, wherein the adhesive film is on the optical path modulator, and Wherein, the optical path modulator is located in the hole in the first region, and is surrounded by the colored resin, the first reflector and the adhesive film. 25. The backlight unit according to claim 24, further comprising: A material disposed between the adhesive film and the colored resin, the material having a different refractive index from that of the colored resin. 26. The backlight unit of claim 24, wherein the first reflector has a height higher than that of the colored resin. 27. The backlight unit of claim 24, further comprising: a substrate including a groove corresponding to the first region, and wherein a reflective film is applied to the substrate. 28. The backlight unit according to claim 24, further comprising: A phosphor film disposed over the light modifying sheet, the phosphor film including a phosphor having a color different from that of the colored resin. 29. The backlight unit of claim 24, wherein the colored resin includes two types of phosphors having different colors. 30. The backlight unit according to claim 24, further comprising: A second reflector disposed on the upper surface of the light emitting device. 31. The backlight unit of claim 24, wherein a thickness of the light modifying pattern gradually decreases from a central area of the backlight unit to an outer area of the backlight unit. 32. The backlight unit of claim 24, wherein the light modifying pattern is configured to have different structures for different regions in the backlight unit. 33. A display device comprising: display panel; a backlight unit disposed under the display panel, the backlight unit configured to radiate light toward the display panel; Wherein, the backlight unit includes: A light emitting device having a flip-chip structure; a first reflector disposed to surround a first region including the light emitting device and a periphery of the light emitting device; a colored resin disposed in the first region; an adhesive film disposed over the colored resin to be spaced apart from the colored resin by a predetermined distance; an optical path modulator above the light emitting device and on the colored resin; and a light modifying patch disposed on said adhesive film, said light modifying patch comprising a light modifying pattern arranged to correspond to a position of said light emitting device, wherein the adhesive film is on the optical path modulator, and Wherein, the optical path modulator is located in the hole in the first region, and is surrounded by the colored resin, the first reflector and the adhesive film. 34. The display device according to claim 33, further comprising: A material disposed between the adhesive film and the colored resin, the material having a different refractive index from that of the colored resin. 35. The display device of claim 33, wherein the first reflector has a height higher than that of the colored resin. 36. The display device according to claim 33, wherein the backlight unit further comprises: a substrate including a groove corresponding to the first region, and wherein a reflective film is applied to the substrate . 37. The display device of claim 33, further comprising: A phosphor film disposed over the light modifying sheet, the phosphor film including a phosphor having a color different from that of the colored resin. 38. The display device of claim 33, wherein the colored resin includes two types of phosphors having different colors. 39. The display device of claim 33, further comprising: A second reflector disposed on the upper surface of the light emitting device.

Images