KR20130000903A

KR20130000903A - Backlight unit and display apparatus using the same

Info

Publication number: KR20130000903A
Application number: KR1020110061714A
Authority: KR
Inventors: 장지원
Original assignee: 엘지이노텍 주식회사
Priority date: 2011-06-24
Filing date: 2011-06-24
Publication date: 2013-01-03

Abstract

A backlight unit and a display device using the same, comprising a light guide plate and a light source module disposed under the light guide plate, wherein the light guide plate includes at least one first groove formed on an upper surface thereof and at least one second groove formed on a lower surface thereof. The first groove and the second groove may be disposed to correspond to each other, and the light source module may be disposed in the second groove of the lower surface.

Description

Backlight unit and display apparatus using the same

An embodiment relates to a backlight unit and a display device using the same.

Typically, typical large-sized display devices include a liquid crystal display (LCD), a plasma display panel (PDP), and the like.

Unlike the self-luminous PDP, an LCD requires a separate backlight unit due to the absence of its own light emitting device.

The backlight unit used in LCD is classified into an edge type backlight unit and a direct type backlight unit according to the position of the light source. In the edge type, the light source is disposed on the left and right sides or the top and bottom sides of the LCD panel and the light guide plate is used. Since the light is evenly distributed on the front surface, the light is uniform and the panel thickness can be made ultra thin.

The direct-type method is generally used for a display of 20 inches or more, and since the light source is arranged at a lower portion of the panel, the light efficiency is higher than that of the edge method. Thus, it is mainly used for a large display requiring high brightness.

CCFL (Cold Cathode Fluorescent Lamp) was used as the light source of the existing edge type or direct type backlight unit.

However, since the CCFL-based backlight unit is always powered by the CCFL, a considerable amount of power is consumed, and the problems of environmental pollution due to the addition of about 70% color reproduction rate and mercury are pointed out as disadvantages.

As a substitute for solving the above problems, research on a backlight unit using an LED (Light Emitting Diode) has been actively conducted.

When the LED is used as a backlight unit, the LED array can be partially turned on and off, which can drastically reduce the power consumption. For the RGB LED, it exceeds 100% of the NTSC (National Television System Committee) color reproduction range specification. To provide consumers with more vivid picture quality.

An embodiment is to provide a backlight unit and a display device using the same that can provide a uniform brightness by modifying the shape of the light guide plate.

The embodiment includes a light guide plate and a light source module disposed under the light guide plate, wherein the light guide plate includes at least one first groove formed on an upper surface thereof and at least one second groove formed on a lower surface thereof. The second grooves may be disposed to correspond to each other, and the light source module may be disposed in the second grooves of the lower surface.

Here, the first groove and the second groove of the LGP may have at least one of a V-shaped stripe having a peak point and an inclined side surface, a cone, a triangular pyramid, a square pyramid, a polygonal pyramid, and a hemispherical shape.

The vertex of the first groove and the vertex of the second groove may be disposed to face each other at a first interval, and the ratio between the first interval and the thickness of the light guide plate may be 0.01 to 0.5: 1.

Subsequently, a ratio between the depth of the first groove or the second groove and the thickness of the light guide plate may be 0.1 to 0.5: 1.

In addition, the depth of the second groove may be deeper than the depth of the first groove, and the depth ratio of the first groove and the second groove may be 0.5-0.99: 1.

Next, the depth of the second groove may be greater than the height of the light source module, and the width of the second groove may be greater than the width of the light source module.

The side surface of the first groove may be a convex curved surface or a plane, and the upper surface of the light guide plate between the first groove and the first groove may be a convex curved surface or a plane.

Subsequently, a side surface of the second groove may be a concave curved surface or a plane, and a lower surface of the light guide plate between the second groove and the second groove may be flat.

Next, at least one of the first groove and the second groove may be a stripe shape or a dot shape arranged in one direction.

In addition, at least one of the side surfaces of the first groove and the second groove may have an uneven shape.

Embodiments may provide grooves in the upper and lower portions of the light guide plate to provide uniform luminance without loss of light.

In addition, the embodiments may reduce the overall thickness of the display device including the backlight unit by positioning the light source module in the groove of the light guide plate.

1 is a cross-sectional view showing a backlight unit according to an embodiment
2A and 2B show a light guide plate according to the first embodiment;
3A and 3B illustrate an arrangement relationship between the light guide plate and the light source module of FIG. 2.
4A to 4C show a light guide plate having a second groove that is a polygonal pyramid;
5A to 5C show a light guide plate having a hemispherical second groove.
6 is a view for comparing the thickness of the light guide plate and the depth of the groove;
7 is a view showing an uneven shape formed on a side of a groove of a light guide plate
8A to 8D illustrate an arrangement relationship between the light guide plate and the light source module according to the second embodiment.
9 illustrates a display module having a backlight unit according to an embodiment.
10 and 11 illustrate a display device according to an embodiment.

Hereinafter, exemplary embodiments will be described with reference to the accompanying drawings.

In the description of the present embodiment, when described as being formed on the "on or under" of each element, the (top) or (bottom) ( on or under includes both that two elements are in direct contact with one another or one or more other elements are formed indirectly between the two elements.

In addition, when expressed as "on" or "under", it may include the meaning of the downward direction as well as the upward direction based on one element.

1 is a cross-sectional view illustrating a backlight unit according to an embodiment.

As shown in FIG. 1, the backlight unit includes a light guide plate 20, a reflector 30, an optical member 40, and a light source module 50. It may include.

The backlight unit may further include a top chassis 60, a bottom chassis 70, and a panel guide module 80.

Here, the panel guide module 80 may support the display panel 90, and the top chassis 60 may be connected to the panel guide module 80 and the bottom chassis 70.

Subsequently, at least one first groove 22 may be formed on the upper surface of the light guide plate 20, and at least one second groove 24 may be formed on the lower surface of the light guide plate 20.

In this case, the first groove 22 of the upper surface and the second groove 24 of the lower surface may be disposed to correspond to each other.

In addition, the light guide plate 20 may be formed of an acrylic resin such as polymethylmethacrylate (PMMA), polyethylene terephthlate (PET), cyclic olefin copolymers (COC), polyethylene naphthalate (PEN), polycarbonate (PC), polystyrene (PS), and MS (Mathacylate). styrene) resin can be any one.

The light source module 50 may be disposed in the second groove 24 of the lower surface of the light guide plate 20.

The light source module 50 may include a substrate 54 and at least one light source 52 disposed on the substrate 54.

Here, both the substrate 54 and the light source 52 may be disposed inside the second groove 24 of the light guide plate 20, and the substrate 54 is disposed outside the second groove 24 of the light guide plate 20. The light source 52 may be disposed in the second groove 24 of the light guide plate 20.

Next, the optical member 40 may be disposed on the upper surface of the light guide plate 20.

Here, the optical member 40 is for diffusing light emitted through the light guide plate 20, and may have an uneven pattern on the upper surface to increase the diffusion effect.

In addition, the optical member 40 may be formed of several layers, and the uneven pattern may be on the surface of the uppermost layer or any one layer.

In addition, the uneven pattern may have a stripe shape disposed along the light source module 50.

At this time, the uneven pattern has a protrusion on the surface of the optical member 40, the protrusion is composed of a first surface and a second surface facing each other, the angle between the first surface and the second surface may be an obtuse angle or acute angle.

In some cases, the optical member 40 includes at least one sheet, and may include a diffusion sheet, a prism sheet, a brightness enhancement sheet, and the like.

Here, the diffusion sheet diffuses the light emitted from the light source, and the prism sheet guides the diffused light to the light emitting area, and the brightness diffusion sheet strengthens the brightness.

Subsequently, the reflector 30 may be disposed on the lower surface of the light guide plate 20.

That is, the reflector 30 may be disposed between the light guide plate 20 and the bottom chassis 70, and may extend from the lower surface of the light guide plate 20 to the side surface.

Here, the reflector 30 is not formed below the substrate 54 of the light source module 50, but may be formed under the substrate 54 of the light source module 50 in some cases.

Here, the reflector 30 may include at least one of a metal and a metal oxide. For example, the reflector 30 may have a high reflectance such as aluminum (Al), silver (Ag), gold (Au), or titanium dioxide (TiO ₂ ). The branch may comprise a metal or metal oxide.

2A and 2B show a light guide plate according to a first embodiment, in which FIG. 2A is a sectional view of the light guide plate, and FIG. 2B is a perspective view of the light guide plate.

As illustrated in FIGS. 2A and 2B, the light guide plate 20 may include a first region in which grooves are formed and a second region in which grooves are not formed between adjacent first regions.

The light guide plate 20 may have at least one first groove 22 formed on the upper surface 20a.

Here, the first groove 22 may be formed in the first region of the light guide plate 20, and may have a V-shaped stripe shape having a peak point 22a and having an inclined side surface.

In some cases, the first groove may be at least one of a cone, a triangular pyramid, a square pyramid, a polygonal pyramidal shape, and a hemispherical shape.

In addition, the side surface 22b of the first groove 22 may be a convex curved surface or may be flat.

In the upper surface 20a of the light guide plate 20, the second area of the light guide plate 20 positioned between the first areas may be a convex curved surface or a flat plane.

Subsequently, at least one second groove 24 may be formed in the lower surface 20b of the light guide plate 20.

Here, the second groove 24 may be formed in the first region of the light guide plate 20 and may have a V-shaped stripe shape having a peak point 24a and having an inclined side surface, or a cone or a triangular pyramid. , At least one of a square pyramid, a polygonal pyramidal shape, and a hemispherical shape.

The side surface 24b of the second groove 24 may be a concave curved surface or may be flat.

In addition, on the lower surface 20b of the light guide plate 20, the second area of the light guide plate 20 positioned between the first areas may be a flat plane.

In addition, the first groove 22 formed in the upper surface 20a of the light guide plate 20 and the second groove 24 formed in the lower surface 20b of the light guide plate 20 may be disposed to face each other. have.

Here, the vertex of the first groove 22 and the vertex of the second groove 24 may be disposed to face each other at a predetermined interval apart.

Subsequently, at least one of the first groove 22 and the second groove 24 may have a stripe shape arranged in one direction.

In some cases, at least one of the first groove 22 and the second groove 24 may have a dot shape in which adjacent grooves are spaced apart from each other by a predetermined distance.

As such, the reason for forming the first grooves 22 and the second grooves 24 on the upper and lower portions of the light guide plate 20 is that light generated by the light source 52 is refracted by the groove shape, and thus the light guide plate 20 is formed. Can be uniformly diffused within.

In addition, since the light generated by the light source 52 is diffused by the groove of the light guide plate 20, it is possible to reduce the hot spot phenomenon occurring in the region adjacent to the light source 52.

3A and 3B illustrate an arrangement relationship between the light guide plate and the light source module of FIG. 2. FIG. 3A is a perspective view and FIG. 3B is a plan view.

As shown in FIGS. 3A and 3B, at least one first groove 22 is formed in the first region of the upper surface of the light guide plate 20, and in the first region of the lower surface of the light guide plate 20. At least one second groove 24 may be formed.

Here, the first groove 22 and the second groove 24 may be disposed to face each other to correspond to each other, and may be disposed in a stripe shape in one direction.

Here, the light source module 50 may include a substrate 54 and at least one light source 52 disposed on the substrate 54, wherein the substrate 54 is formed along the stripe-shaped second groove 24. It is arranged and has a stripe shape.

That is, one substrate 54 may be disposed in one second groove 24, and at least one light source 52 may be disposed on one substrate 54.

In some cases, a plurality of substrates 54 may be disposed in one second groove 24, and at least one light source 52 may be disposed on one substrate 54.

In addition, both the substrate 54 and the light source 52 may be disposed inside the second groove 24 of the light guide plate 20, and the substrate 54 may be disposed outside the second groove 24 of the light guide plate 20. The light source 52 may be disposed in the second groove 24 of the light guide plate 20.

As described above, at least one light source 52 may be mounted on the substrate 54 of the light source module 50, and an electrode pattern for connecting the power supply adapter and the light source 52 may be formed.

For example, an electrode pattern for connecting the light source 52 and the adapter may be formed on the upper surface of the substrate 54.

The substrate 54 may be a printed circuit board (PCB) substrate made of any one material selected from polyethylene terephthalate (PET), glass, polycarbonate (PC), and silicon (Si), or may be formed in a film form. .

In addition, the substrate 54 may selectively use a single layer PCB, a multilayer PCB, a ceramic substrate, a metal core PCB, or the like.

At least one light source 52 may be disposed on the substrate 54, and the light source 52 may be a top view type light emitting diode.

In some cases, the light source 52 may be a side view type light emitting diode.

As such, the light source 52 may be a light emitting diode chip, and the light emitting diode chip may include a blue LED chip or an ultraviolet LED chip, or a red LED chip, a green LED chip, a blue LED chip, and yellow green. green) may be configured in the form of a package combining at least one or more of the LED chip, white LED chip.

Here, the white LED may be implemented by combining yellow phosphor on the blue LED, or simultaneously using red phosphor and green phosphor on the blue LED, and yellow phosphor on the blue LED. Yellow phosphor, red phosphor, and green phosphor may be simultaneously used.

4A to 4C illustrate a light guide plate having a second groove that is a polygonal pyramid.

In FIG. 4A, the first groove 22 formed in the first region of the upper surface of the light guide plate 20 may have a curved surface having convex sides, and the surface of the second region may also have a curved surface.

In addition, the second groove 24 formed in the first region of the lower surface of the light guide plate 20 may have a flat planar side, and the surface of the second region may also have a flat planar shape.

4B, the first groove 22 formed in the first region of the upper surface of the light guide plate 20 may have a curved surface having a convex side surface, and the surface of the second region may have a flat planar shape.

Next, in FIG. 4C, the first groove 22 formed in the first region of the upper surface of the light guide plate 20 may have a flat planar side, and the surface of the second region may also have a flat planar shape.

5A through 5C are diagrams illustrating a light guide plate having a hemispherical second groove.

5A, the first groove 22 formed in the first region of the upper surface of the light guide plate 20 may have a curved surface having a convex side, and the surface of the second region may also have a curved surface.

The second groove 24 formed in the first region of the lower surface of the light guide plate 20 may have a curved surface having a concave side surface, and the surface of the second region may have a flat planar shape.

Subsequently, in FIG. 5B, the first groove 22 formed in the first region of the upper surface of the light guide plate 20 may have a curved surface having convex sides, and the surface of the second region may have a flat planar shape.

Next, in FIG. 5C, the first groove 22 formed in the first region of the upper surface of the light guide plate 20 may have a flat planar side, and the surface of the second region may also have a flat planar shape.

6 is a view for comparing the thickness of the light guide plate and the depth of the groove.

As shown in FIG. 6, at least one first groove 22 may be formed on an upper surface of the light guide plate 20, and at least one second groove 24 may be formed on a lower surface of the light guide plate 20. have.

Here, the first groove 22 and the second groove 24 may be disposed to face each other to correspond to each other, the light source module 50 may be disposed in the second groove 24 of the lower surface of the light guide plate 20. .

In this case, the vertex of the first groove 22 and the vertex of the second groove 24 may be disposed to face each other at a first interval d1.

The ratio of the first interval d1 to the thickness d2 of the light guide plate 20 may be about 0.01-0.5: 1.

The reason is that if the first interval d1 is too small, light diffusion is reduced to increase the hot spot phenomenon, and if the first interval d1 is too large, the light source module 50 is located outside the second groove 24 so that the entire backlight The thickness of the unit may increase.

Subsequently, a ratio between the depths h2 and h1 of the first grooves 22 or the second grooves 24 and the thickness d1 of the light guide plate 20 may be about 0.1 to 0.5: 1.

Here, the depth h1 of the second groove 24 may be deeper than the depth h2 of the first groove 22.

This is because the light source module 50 should be disposed in the second groove 24.

Here, the ratio of the depth h2 of the first groove 22 and the depth h1 of the second groove 24 may be 0.5-0.99: 1.

In some cases, the depth h1 of the second groove 24 and the depth h2 of the first groove 22 may be the same.

In addition, the depth h1 of the second groove 24 may be greater than the height h3 of the light source module 50.

In addition, the width w2 of the second groove 24 may be larger than the width w1 of the light source module 50.

FIG. 7 is a view illustrating an uneven shape formed on a side of a groove of the light guide plate.

As illustrated in FIG. 7, at least one of the first groove 22 formed in the upper surface of the light guide plate 20 and the second groove 24 formed in the lower surface of the light guide plate 20 may have an uneven pattern on a side surface thereof. This can be formed.

That is, the first uneven pattern 22c may be formed in the first groove 22 side surface 22b of the light guide plate 20, and the second unevenness may be formed in the side surface 24b of the second groove 24 of the light guide plate 20. The pattern 24c may be formed.

Here, the 1st, 2nd uneven | corrugated patterns 22c and 24c may be saw-tooth-shaped in a flat surface, and may be sawtooth-shaped in surface or convex curved surface.

In some cases, the size of the concave-convex pattern may become gradually smaller toward the apex of the groove.

As such, the reason for forming the first and second uneven patterns 22c and 24c on the side surfaces of the first and second grooves 22 and 24 of the light guide plate 20 is to increase the diffusion effect of uniformly spreading the light. Because it can.

Therefore, the shape of the groove or the uneven pattern may be manufactured in various sizes in the corresponding area according to the overall luminance distribution of the backlight.

8A to 8D are views illustrating an arrangement relationship between the light guide plate and the light source module according to the second embodiment, in which FIG. 8A is a perspective view, FIG. 8B is a top view, FIG. 8C is a rear view, and FIG. 8D is a sectional view. .

8A to 8D, the light guide plate 20 has a plurality of first grooves 22 formed on an upper surface thereof, and the first grooves 22 adjacent to each other are disposed to be spaced apart from each other by a dot. ) May be shaped.

In addition, the light guide plate 20 may have a dot shape in which a plurality of second grooves 24 are formed on a lower surface thereof, and second grooves 24 adjacent to each other are also spaced apart from each other by a predetermined distance.

The first grooves 22 formed on the upper surface of the light guide plate 20 may be disposed to face each other in a one-to-one correspondence with the second grooves 24 formed on the lower surface of the light guide plate 20.

Here, the first groove 22 may be a cone shape having a peak point, but in some cases, the first groove 22 may have a V-shaped stripe, a triangular pyramid, a square pyramid, and a polygonal pyramid having inclined sides. At least one of, and hemispherical shape may be sufficient.

In this case, the side surface of the first groove 22 may be a convex curved surface or may be a flat surface.

The second groove 24 may have a square pyramid shape having a peak point, but in some cases, at least one of a V-shaped stripe, a cone, a triangular pyramid, a polygonal pyramid shape, and a hemispherical shape having an inclined side surface. It may be.

Here, the side surface of the second groove 24 may be a concave curved surface or may be flat.

As such, the reason for forming the first grooves 22 and the second grooves 24 on the upper and lower portions of the light guide plate 20 is that light generated by the light source 52 is refracted by the groove shape, and thus the light guide plate 20 is formed. It is because it can spread uniformly inside.

Here, the light source module 50 may include a substrate 54 and at least one light source 52 disposed on the substrate 54. The substrate 54 may correspond to a dot-shaped second groove 24. Can be arranged.

As such, the embodiments may provide grooves in the upper and lower portions of the light guide plate to provide uniform luminance without loss of light.

9 is a view illustrating a display module having a backlight unit according to an embodiment.

As shown in FIG. 9, the display module 200 may include a display panel 90 and a backlight unit 100.

The display panel 90 includes a color filter substrate 91 and a TFT (Thin Film Transistor) substrate 92 bonded to face each other to maintain a uniform cell gap, and a liquid crystal between the two substrates 91 and 92. A layer (not shown) may be interposed.

The color filter substrate 91 includes a plurality of pixels including red (R), green (G), and blue (B) sub-pixels, and generates an image corresponding to the color of red, green, or blue when light is applied. You can.

The pixels may be composed of red, green, and blue subpixels, but the red, green, blue, and white (W) subpixels constitute one pixel, but are not necessarily limited thereto.

The TFT substrate 92 may switch a pixel electrode (not shown) as an element on which switching elements are formed.

For example, the common electrode (not shown) and the pixel electrode may change the arrangement of molecules of the liquid crystal layer according to a predetermined voltage applied from the outside.

The liquid crystal layer is composed of a plurality of liquid crystal molecules, and the liquid crystal molecules change their arrangement corresponding to the voltage difference generated between the pixel electrode and the common electrode.

As a result, the light provided from the backlight unit 100 may be incident on the color filter substrate 91 in response to the change in the molecular arrangement of the liquid crystal layer.

In addition, an upper polarizer 93 and a lower polarizer 94 may be disposed above and below the display panel 90, and more specifically, an upper polarizer 93 may be disposed on an upper surface of the color filter substrate 91. The lower polarizer 94 may be disposed on the bottom surface of the TFT substrate 92.

Although not shown, a gate and a data driver for generating a driving signal for driving the display panel 90 may be provided on the side of the display panel 90.

As shown in FIG. 9, the display module 200 may be configured by closely placing the backlight unit 100 on the display panel 90.

For example, the backlight unit 100 may be adhered to and fixed to the lower side of the display panel 90, more specifically, the lower polarizer 94, and for this purpose, between the lower polarizer 94 and the backlight unit 100. An adhesive layer (not shown) may be formed on the substrate.

As such, by forming the backlight unit 100 in close contact with the display panel 90, the overall thickness of the display device may be reduced to improve appearance, and an additional structure for fixing the backlight unit 100 may be removed. The structure and manufacturing process of the display device can be simplified.

In addition, by removing the space between the backlight unit 100 and the display panel 90, it is possible to prevent the malfunction of the display device or the deterioration of the display image quality due to the infiltration of foreign matter into the space.

10 and 11 illustrate a display device according to an embodiment.

First, as shown in FIG. 10, the display apparatus 1 is provided in the display module 200, the front cover 300, the back cover 350, and the back cover 350 surrounding the display module 200. It may be composed of a driving unit 550 and a driving unit cover 400 surrounding the driving unit 550.

The front cover 300 may include a front panel (not shown) of a transparent material that transmits light, and the front panel protects the display module 200 at regular intervals, and the light emitted from the display module 200. The light is transmitted through the display module 200 so that the image displayed on the display module 200 is viewed from the outside.

In addition, the front cover 300 may be made of a flat plate without the window 300a.

In this case, the front cover 300 may be made of a transparent material that transmits light, for example, injection molded plastic.

As such, when the front cover 300 is formed of a flat plate, the frame can be removed from the front cover 300.

The back cover 350 may be combined with the front cover 300 to protect the display module 200.

The driving unit 550 may be disposed on one surface of the back cover 350.

The driver 550 may include a drive controller 550a, a main board 550b, and a power supply unit 550c.

The driving control unit 550a may be a timing controller. The driving control unit 550a may be a driving unit for adjusting an operation timing of each driver IC of the display module 200. And a driving unit for transmitting G and B resolution signals, and the power supply unit 550c may be a driving unit for applying power to the display module 200.

The driver 550 may be provided in the back cover 350 and may be wrapped by the driver cover 400.

A plurality of holes may be provided in the back cover 350 to connect the display module 200 and the driver 550, and a stand 600 supporting the display apparatus 1 may be provided.

Subsequently, as shown in FIG. 11, the driving controller 550a of the driving unit 550 may be provided in the back cover 350, and the main board 550b and the power board 550c may be provided in the stand 600. have.

In addition, the driver cover 400 may wrap only the driver 550 provided in the back cover 350.

In an embodiment, the main board 550b and the power board 550c are separately configured, but may be formed as one integrated board, but the present invention is not limited thereto.

Features, structures, effects, and the like described in the above embodiments are included in at least one embodiment of the present invention, and are not necessarily limited to only one embodiment. Furthermore, the features, structures, effects, and the like illustrated in each embodiment may be combined or modified with respect to other embodiments by those skilled in the art to which the embodiments belong. Therefore, it should be understood that the present invention is not limited to these combinations and modifications.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of illustration, It can be seen that various modifications and applications are possible. For example, each component specifically shown in the embodiments can be modified and implemented. It is to be understood that all changes and modifications that come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Claims

Light guide plate; And
A light source module disposed under the light guide plate;
The light guide plate,
At least one first groove formed on the upper surface,
At least one second groove formed in the lower surface,
The first groove and the second groove are disposed to correspond to each other,
The light source module is disposed in the second groove of the lower surface.

2. The light guide plate of claim 1, wherein the first grooves and the second grooves of the light guide plate have a peak point 22a and are inclined at a side, V-shaped stripe, cone, triangular pyramid, square pyramid, polygonal pyramid, and hemispherical shape. At least one of the backlight unit.

The backlight unit of claim 2, wherein the vertex of the first groove and the vertex of the second groove are disposed to face each other at a first interval.

The backlight unit of claim 3, wherein a ratio between the first interval and the thickness of the light guide plate is 0.01 to 0.5: 1.

The backlight unit of claim 1, wherein a ratio of a depth of the first groove or the second groove to a thickness of the light guide plate is 0.1 to 0.5: 1.

The backlight unit of claim 1, wherein a depth of the second groove is deeper than a depth of the first groove.

The backlight unit of claim 6, wherein a depth ratio of the first groove to the second groove is 0.5 to 0.99: 1.

The backlight unit of claim 1, wherein a depth of the second groove is greater than a height of the light source module.

The backlight unit of claim 1, wherein a width of the second groove is greater than a width of the light source module.

The backlight unit of claim 1, wherein a side surface of the first groove is a convex curved surface or a flat surface.

The backlight unit of claim 1, wherein the light guide plate upper surface between the first groove and the first groove is a convex curved surface or a plane.

The backlight unit of claim 1, wherein a side surface of the second groove is a concave curved surface or a flat surface.

The backlight unit of claim 1, wherein the light guide plate lower surface between the second groove and the second groove is flat.

The backlight unit of claim 1, wherein at least one of the first groove and the second groove has a stripe shape or a dot shape arranged in one direction.

The backlight unit of claim 1, wherein at least one of the side surfaces of the first groove and the second groove has a concave-convex shape.

The method of claim 1, wherein the light guide plate is any one of polymethylmethacrylate (PMMA), polyethylene terephthlate (PET), cyclic olefin copolymers (COC), polyethylene naphthalate (PEN), polycarbonate (PC), polystyrene (PS), and matercylate styrene (MS). One backlight unit.

The method of claim 1,
The light source module,
At least one substrate disposed in a second groove of the light guide plate;
And at least one light source arranged on the substrate.

18. The backlight unit of claim 17, wherein the light source is a top emitting light emitting diode.

The method of claim 1,
An optical member disposed on an upper surface of the light guide plate;
The backlight unit further comprises a reflector disposed on the lower surface of the light guide plate.

Display panel;
It includes a backlight unit for irradiating light to the display panel,
20. The display apparatus using the backlight unit of claim 1, wherein the backlight unit is any one of the backlight units of claim 1.