KR20110027185A - Light guide plate and backlight unit having the same - Google Patents

Abstract

PURPOSE: A light guide plate and a backlight unit including the same are provided to improve the uniformity of light by forming different patterns on a hot spot area and a dark area in an incident unit of the light guide plate. CONSTITUTION: A light guide plate(10) includes an incident surface, an upper surface, and a lower surface. Light is inputted to an incident surface. A first pattern(11) and a second pattern(22) change the direction of incident light. The lower surface includes the first and second patterns and is adjacent to the incident surface. The upper plate emits light.

Description

Light guide plate and backlight unit having the same {light guide plate and backlight unit having the same}

An embodiment relates to a light guide plate and a backlight unit having the same.

The display device is a CRT (Cathode Ray Tube), a liquid crystal display (LCD) using an electro-optic effect, a plasma display device (PDP: Plasma Display Panel) using a gas discharge and an EL display device using an electroluminescent effect (ELD: Electro Luminescence Display), among which researches on liquid crystal displays are being actively conducted.

Since most liquid crystal display devices are light-receiving devices that display an image by controlling the amount of light coming from the outside, a separate light source for illuminating the LCD panel, that is, a backlight unit, is required.

An embodiment of the present invention is to provide a light guide plate in which a pattern is formed on one surface of which a part different from the pattern is applied.

An embodiment is to provide a light guide plate and a method of manufacturing the light guide plate which can improve light uniformity by applying a different pattern to the dark region of the light incident portion to which light is incident.

An embodiment is to provide a backlight unit having a light guide plate.

The light guide plate according to the embodiment includes a light incident surface on which light is incident, a lower surface including a second pattern formed near the light incident surface and changing a direction of the incident light, and an upper surface emitting the light.

The backlight assembly according to the embodiment may include a light source for generating light, a light incident surface on which the light is incident, a second pattern for changing a direction of the incident light on first areas adjacent to the light incident surface, and the light. It includes a light guide plate including an upper surface to emit.

The embodiment has the effect of increasing the light uniformity of the light guide plate by forming the patterns formed in the dark region and the hot spot region in the light incident portion of the light guide plate different from each other.

The embodiment has the effect of reducing the luminance deviation between the light incident portion and the light portion of the light guide plate.

According to the embodiment, it is possible to improve the problem of dark part generation of the backlight unit, so that the interval of arrangement of the light emitting diodes can be widened, thereby reducing the manufacturing cost by reducing the number of light emitting diodes.

Therefore, the light efficiency and uniformity of the backlight unit may be improved, and the brightness of the display device having the backlight unit may be improved.

Hereinafter, with reference to the accompanying drawings as follows.

In the description of the embodiments, it is described that each panel, layer, film, member or substrate or the like is formed “on” or “under” of each panel, layer, film, member or substrate or the like. In the case, “on” and “under” include both being formed “directly” or “indirectly” through other components. In addition, the upper or lower reference of each component is described with reference to the drawings. The size of each component in the drawings may be exaggerated for the sake of explanation and does not mean the size actually applied.

1 is a plan view illustrating an arrangement of a light guide plate and a light source.

Referring to FIG. 1, the backlight unit includes a light guide plate and a light source.

The light source includes at least one light emitting diode 20 and a module substrate 30 on which the light emitting diode 20 is mounted.

The light emitting diode 20 may be a colored LED such as a red LED, a blue LED, a green LED, or a white LED, but is not limited thereto.

The module substrate 30 is made of a metal core PCB, FR-4 PCB, general PCB, etc., it can be variously changed within the technical scope of the embodiment.

The light guide plate 10 may include an acrylic resin of a transparent material that may transmit light. For example, the light guide plate 10 may include at least one of a group consisting of PMMA, PC, and PET.

The light guide plate 10 may be flexible.

Patterns may be formed on one or both surfaces of the light guide plate 10.

The light guide plate 10 receives light from the light emitting diode 20 and emits light in a front direction through reflection, refraction, and scattering.

The light emitting diode 20 has a light directing angle as a point light source and is generated in a fan shape, and the light guide plate 10 is spaced at predetermined intervals by the light emitting diode 20 having such characteristics. The light may not be directly incident to each other so that the dark region A having a relatively low luminance may be formed.

2 and 3 are plan views showing a pattern of a bottom surface of the light guide plate according to the first embodiment and a perspective view of the light guide plate.

Referring to FIG. 2, the light guide plate 10 may be formed of four side surfaces, a top surface on which a surface light source is generated, and a bottom surface facing the top surface.

The light guide plate 10 may have a rectangular planar shape, but is not limited thereto.

The lower surface of the light guide plate 10 has a first edge 1, a second edge facing the first edge 1, and a third edge in contact with the first and second edges 1 and 2 ( 3) and a fourth corner 4 facing the third corner 3.

A pattern 11 is formed on the bottom surface of the light guide plate 10.

The light source may be disposed near the fourth edge 4 of the light guide plate 10. That is, the light generated by the light source 4 may be incident to one side of the light guide plate 10 connected to the fourth edge 4. A light incident portion may be referred to as a light incident portion, and a side opposite to the light source 4 may be referred to as a light incident portion.

The light emitting diode 20 has a light directing angle as a point light source and is generated in a fan shape, and the light guide plate 10 is spaced at predetermined intervals by the light emitting diode 20 having such characteristics. ) And a first region 21 having a relatively low luminance and a second region having a relatively high luminance in front of the light emitting diodes.

First patterns 11 and second patterns 22 are formed on the bottom surface of the light guide plate 10.

The first patterns 11 may be formed as line patterns. For example, the first patterns 11 may be formed in a prism pattern having a triangular cross section. However, the shape of the first patterns 11 is not limited thereto.

The first patterns 11 may be formed of lines crossing one surface of the light guide plate 10 from the first edge 1 to the second edge 2 of the light guide plate 10.

The first patterns 11 may be formed parallel to the third and fourth edges 3 and 4.

A pattern interval, that is, a pitch, may increase as the first edges 11 of the first patterns 11 move from the vicinity of the third edge 3 to the fourth edge 4.

The second patterns 22 are formed in a portion of the lower surface of the light guide plate 10 that is in contact with the fourth edge 4.

The second patterns 22 may be formed in the first regions 21 in which dark portions are expected to occur.

The second patterns 22 may be formed of line patterns.

The second patterns 22 may be formed parallel to the first patterns 11.

An interval between the second patterns 22 may be formed to be constant.

As shown in FIG. 3, another pattern may be formed on the upper surface of the light guide plate 10. The pattern 23 formed on the upper surface of the light guide plate 10 may serve to increase luminance by condensing the light emitted from the light guide plate 10 to the front.

4 is a cross-sectional view of the light guide plate according to the first embodiment taken along the line II ′ of FIG. 2, and FIG. 5 is a cross-sectional view of the light guide plate according to the second embodiment.

Referring to FIG. 4, the first pattern 11 and the second pattern 22 of the light guide plate 10 are patterns formed concave into the light guide plate 10. The cross-sectional shape of the pattern may be triangular.

Referring to FIG. 5, the first pattern 11a and the second pattern 22a of the light guide plate 10 are patterns formed convexly to the outside of the light guide plate 10.

6 is a plan view illustrating an example of a second pattern of the light guide plate according to the third embodiment.

The second pattern 22b is formed in the dark region generated in the light guide plate 10 between the light emitting diodes 20 by the direction of the light emitting diodes 20 disposed on the side of the light guide plate 10.

Referring to FIG. 6, the second patterns 22b may be formed in the first region 21 where the dark portion is expected to occur.

The second patterns 22b may be formed of line patterns.

The second patterns 22b may be formed parallel to the fourth corner 4.

The distance between the second patterns 22b may become narrower as the distance from the fourth edge 4 increases (P1> P2).

7 is a plan view illustrating another example of the second pattern of the light guide plate according to the fourth embodiment.

Referring to FIG. 7, the second patterns 22 may be formed in the first regions 21 where the dark portion is expected to occur.

The second patterns 22c may be formed of line patterns.

The second patterns 22c may be formed parallel to the fourth corner 4.

The interval between the second patterns 22c may be formed to be constant.

The distance between the second patterns 22c may be wider as the distance from the fourth corner 4 increases (P1 <P2).

8 is a plan view illustrating still another example of the second pattern of the light guide plate according to the fifth embodiment.

Referring to FIG. 8, the second patterns 22d may be formed in the first regions 21 in which dark portions are expected to occur.

The second patterns 22d may be formed of dot patterns.

The distribution density of the dot patterns may be different or the same depending on the position. The distribution density of such dot patterns may be selectively designed within a range capable of improving dark spot generation in the first region 21.

9 is a plan view illustrating another example of a second pattern of the light guide plate according to the sixth embodiment.

As described above, the shape of the first region 21 in which the second pattern 22e is formed may be a triangle having a bottom edge of the fourth corner 4. However, the present invention is not limited thereto, and may be polygonal or semi-circular as shown in FIG. 9.

Here, according to the exemplary embodiments, the first region 21 is a region in which the second pattern 22e is formed, and the first region 21 is divided by the second patterns 22e and has a separate boundary. It may not be.

10 is a plan view illustrating a bottom surface of the light guide plate according to the seventh embodiment.

Referring to FIG. 10, the light guide plate 10 corresponds to the light emitting diodes 20, and since the light is not directly incident due to the light directing angle of the light emitting diodes 20, the first region 21 having a relatively low luminance is provided. And a second region 31 corresponding to the front surfaces of the light emitting diodes 20 and having a relatively high luminance. The first area 21 may be referred to as a dark area.

The first region 21 may have a triangular shape corresponding to the light emitting diodes and having the fourth corner 4 on one side thereof, but is not limited thereto. The first region 21 may form a polygon such as a semicircle, a trapezoid, or a parallelogram.

The second region 31 corresponds to the light emitting diode and may be formed between the first regions 21.

The planar shape of the second region 31 may be a polygon such as a triangle or a quadrangle and may form a semicircle. However, the present invention is not limited thereto.

In addition, the first area 21 and the second area 31 are not formed as a pattern forming a boundary of each area, but are determined by a pattern formed in each area or a pattern formed on the bottom surface of the light guide plate. In FIG. 10, a boundary is indicated by a dotted line in the second region 31 for better understanding, but the pattern is not actually formed on the light guide plate 10.

Referring to FIG. 10, first patterns 11 and second patterns 22 are formed on a bottom surface of the light guide plate 10.

The first patterns 11 may be formed as line patterns. For example, the first patterns 11 may be formed in a prism pattern having a triangular cross section. However, the shape of the first patterns 11 is not limited thereto.

The first patterns 11 may be formed of lines crossing the lower surface of the light guide plate 10 from the first edge 1 to the second edge 2 of the light guide plate 10.

The first patterns 11 may be formed parallel to the third and fourth edges 3 and 4.

The first patterns 11 are not formed in the first region 21 and the second region 31.

A pattern interval, that is, a pitch, may increase as the first edges 11 of the first patterns 11 move from the vicinity of the third edge 3 to the fourth edge 4.

The second patterns 22 may be formed in the first region 21.

The second patterns 22 formed in the first region 21 may be formed of line patterns formed in parallel with the first patterns 11.

The pitch of the second patterns 22 may be smaller than the pitch of the first patterns 11.

The second patterns 22 may be denser than the first patterns 11.

Meanwhile, the first pattern 21 and the second pattern 22 are not formed in the second region 31.

As a result, the path of light is efficiently switched to the upper surface of the first region 21 of the light guide plate 10 by the second patterns 22, and the second region 22 is incident from the light emitting diode 20 in the second region 31. By reducing the switching of the light to the upper surface, a uniform luminance distribution can be obtained at the light exit surface of the light guide plate 10.

11 is a plan view illustrating a portion of a bottom surface of the light guide plate according to the eighth embodiment.

Second patterns 22 and third patterns 33 formed in the first region 21 and the second region 31 of the light guide plate 10 are illustrated.

The second patterns 22 described with reference to FIG. 10 are formed in the first region 21.

Third patterns 33 may be formed in the second region 31. For example, dot patterns may be formed in the second region 31.

First patterns 11 are formed on the bottom surface of the light guide plate 10 except for the first region 21 and the second region 31.

The second patterns 22 effectively change the path of light in the first region 21 of the light guide plate 10 to the upper surface, thereby improving dark spot generation, and in the second region 31, the light emitting diodes 20 are formed. By allowing the incident light to be diffused to the upper surface, it is possible to improve the occurrence of hot spots to obtain a uniform luminance distribution on the light exit surface of the light guide plate 10.

FIG. 12 is a cross-sectional view taken along line II-II 'of FIG. 11, and FIG. 13 is a cross-sectional view taken along line II-II ′ of FIG. 11 according to a ninth embodiment.

Referring to FIG. 12, the third patterns 33 formed in the second region 31 may have a convex shape. The third patterns 33 may form convex dot patterns.

Referring to FIG. 13, the third patterns 33a formed in the second region 31 may have a concave shape. The third patterns 33a may form concave dot patterns.

14 is a plan view illustrating a bottom surface of the light guide plate according to the tenth embodiment.

Referring to FIG. 14, second patterns 22 are formed on the lower surface of the light guide plate 10 in the first region 21, which is a dark region corresponding to the first patterns 11 and the light emitting diodes 20. do.

The second patterns 22 are denser than the first patterns 11.

The first and second patterns 11 and 22 may be prismatic patterns. The prism pattern may be observed in a line in a plane, and the vertical cross section may be triangular in shape. For example, the vertical cross section may be an isosceles triangle.

The third pattern 33b is formed in a region facing the light emitting diodes 20 in the second region 31 formed on the light incident surface to which light is incident from the light emitting diodes 20.

The light incident surface is a side surface perpendicular to the bottom surface of the light guide plate 10, and the bottom surface and the light incident surface contact each other at the fourth edge 4.

The third patterns 33b may be formed to have scattering patterns spaced apart from each other according to the arrangement interval of the light emitting diodes 20. For example, the third patterns 33b may be convex dot patterns or concave dot patterns. However, the third patterns 33b are not limited to dot patterns, and may be formed in various shapes, and may include, for example, prismatic patterns.

The third patterns 33b may improve light spot generation and dark part generation by allowing light incident from the light emitting diode 20 to be diffused and side incident to the light guide plate 10. 22, the path of light in the first region 21 of the light guide plate 10 can be efficiently switched to an upper surface, thereby improving dark spots, thereby obtaining a uniform luminance distribution on the light exit surface of the light guide plate 10.

15 is a plan view illustrating a portion of a lower surface of the light guide plate according to the eleventh embodiment.

A scattering pattern layer 33c is formed on the light incident surface corresponding to the light emitting diode 20.

In the first region 21 corresponding to the light emitting diodes 20 and expected to generate dark portions, second patterns 22 formed of a prism pattern are formed on the lower surface of the light guide plate 10.

The light incident surface and the bottom surface of the light guide plate 10 are formed perpendicular to each other and contact each other at the fourth edge 4.

The scattering pattern layer 33c has a concave dot pattern or a convex dot pattern formed on the transparent film. However, the scattering pattern layer 33c is not limited to the dot pattern, but may be formed in various shapes and may include, for example, a prism pattern.

The light refractive index of the scattering pattern layer 33c and the light refractive index of the light guide plate may be substantially the same.

The scattering pattern layers 33c may be attached to the light incident surface of the light guide plate 10 to face the light emitting diodes 20, respectively.

16 is a plan view illustrating a portion of a lower surface of the light guide plate according to the twelfth embodiment.

The light emitting diode 20 and the module substrate 30 on which the light emitting diode 20 is mounted are disposed to face one side of the light guide plate 10.

Sides of the light guide plate 10 corresponding to the light emitting diode 20 are provided with a space in which the light emitting diode 20 can be inserted into the light guide plate 10.

The space may be provided by a recess 34 recessed into the light guide plate 10 in the second region 31. An inner surface of the recess 34 may form a light incident surface. The light emitting diode 20 may be spaced apart from the light incident surface, and a predetermined scattering pattern may be formed on the light incident surface.

Light generated by the light emitting diodes 20 disposed in the concave portion 34 may be incident on the light guide plate 10 through the light incident surface of the concave portion 34 to reduce the dark portion generation region.

In the lower surface of the light guide plate 10, second patterns 22 are formed in the first region 21 to be parallel to the fourth edge 4. The second patterns 22 may be formed of line patterns. The line patterns 22 may be formed as a concave prism pattern or a convex prism pattern on the lower surface of the light guide plate 10. The vertical cross-sectional shape of the prism pattern may be triangular.

The first region 21 may have a triangular plane shape with the fourth corner 4 as one side.

17 is a plan view illustrating a portion of a lower surface of the light guide plate according to the thirteenth embodiment.

In the thirteenth embodiment shown in FIG. 17, detailed description of parts identical to those shown in FIG. 16 will be omitted.

The second pattern 22 formed in the first region 21 may be a line pattern formed in a direction perpendicular to the fourth edge 4 of the light guide plate 10. The second patterns may have a predetermined pitch.

The second patterns 22 formed perpendicularly to the fourth edge 4 are generated in the light emitting diode 20 so that the advancing direction of the light incident through the light incident surface of the inner surface of the recess 34 is directed toward the light emitting surface direction. Can be converted.

The second patterns 22 need not be formed in a direction perpendicular to the fourth edge 4 on the bottom surface of the light guide plate 10, and the second patterns 22 may not be formed in the fourth corner 4. It may be formed in the inclined direction. The second patterns 22 may be prismatic patterns.

18 is a perspective view illustrating a mold for manufacturing light guide plates according to an embodiment.

The light guide plate 10 according to the embodiment may be injection molded using the mold die 80.

As shown in FIG. 18, the mold 80 includes a lower mold 50 and an upper mold 60.

In the lower mold 50 and the upper mold 60, a cavity 51 is formed to face each other, and side walls 52 are formed to surround each cavity 51. Sidewalls of the lower mold 50 and the upper mold 60 are in contact with each other to provide a space in which the light guide plate is formed by the cavities 51.

The first core 71 and the first split core 72 are formed on the bottom surface of the cavity 51 of the lower mold 50.

The first core 71 and the first split core 72 may be joined to each other to form a bottom surface of the cavity 51 of the lower mold 50.

The first split core 72 may be disposed on one side of the first core 71, and a plurality of first split cores 72 may be disposed at one side of the first core 71 at predetermined intervals. Can be.

The first split core 72 may have various shapes. For example, one side may have a triangular shape forming an outer edge of the bottom surface.

A groove corresponding to each of the first cores 71 may be formed at one side of the first core 71, and both sides of the inner side of each of the grooves may be in contact with each other.

A first groove pattern 71a may be formed in the first core 71 of the lower mold 50. The first groove pattern 71a may be formed of prismatic patterns crossing the bottom surface.

In addition, a second groove pattern 72a may be formed on the first split core 72.

The second groove pattern 72a may be formed of prismatic patterns parallel to the first groove pattern 71a. The second groove pattern 72a may have a pitch smaller than that of the first groove pattern 71a.

The second groove pattern 72a may be formed of prismatic patterns formed in a direction perpendicular to the first groove pattern 71a. The first groove pattern 71a is not limited thereto, and the second groove pattern 72a may be formed of a dot pattern.

A second core (not shown) may be formed on the bottom surface of the cavity of the upper mold 60.

The second core may have a prism pattern or a dot pattern, or may have a flat surface.

When the cavities of the lower mold 50 and the upper mold 60 are joined to face each other, an acrylic resin or the like is injected into the cavity through the resin inlet 53.

The mold frame 80 is heated to form a light guide plate on which the first groove pattern 71a and the second groove pattern 72a are transferred in the cavity. Thereafter, a cooling process may be performed on the mold 80.

The light guide plate 10 according to the embodiment may be manufactured through the above process.

The light guide plate 10 implemented by at least one of the first to thirteenth embodiments described above may be manufactured using the mold 80 described with reference to FIG. 18.

The first groove patterns 71a formed on the first core 71 of the mold frame 80 correspond to the first patterns 11 of the light guide plate 10 and are formed on the first split core 72. The two groove patterns 72a may correspond to the second pattern 22 of the first region 21.

The third pattern 33 of the light guide plate 10 and the second region 31 of the light guide plate 10 is manufactured by manufacturing a mold so that the second split core is disposed between the first split cores 72 of the mold 80. Can be formed.

19 is an exploded perspective view illustrating a display device including a light guide plate according to an embodiment.

Referring to FIG. 19, the display device 100 includes a display panel 110 on which an image is displayed, and a backlight unit 130 that provides light to the display panel 110.

Although not shown in detail, the display panel 110 includes, for example, lower and upper substrates bonded to maintain a uniform cell gap facing each other, and a liquid crystal layer interposed between the two substrates. A plurality of gate lines and a plurality of data lines intersecting the plurality of gate lines may be formed on the lower substrate, and a thin film transistor (TFT) may be formed at an intersection of the gate line and the data line. Color filters may be formed on the upper substrate. The structure of the display panel 110 is not limited thereto, and the display panel 110 may have various structures. In another example, the lower substrate may include not only a thin film transistor but also a color filter. In addition, the display panel 110 may be formed in various shapes according to a method of driving the liquid crystal layer.

Although not shown, a gate driving printed circuit board (PCB) for supplying scan signals to gate lines and a data driving printed circuit board (PCB) for supplying data signals to data lines are provided at edges of the display panel 110. ) May be provided.

A polarizing film (not shown) may be disposed on at least one of the top and bottom of the display panel 110.

An optical sheet 120 may be disposed between the display panel 110 and the backlight unit 130, and the optical sheet 120 may be removed, but is not limited thereto.

The optical sheet 120 may include a diffusion sheet (not shown) and / or a prism sheet (not shown).

The diffusion sheet evenly spreads the light emitted from the light guide plate, and the diffused light may be focused onto the display panel by the prism sheet. Here, the prism sheet may be selectively configured using a horizontal or / and vertical prism sheet, one or more roughness reinforcing films, and the like. The type or number of the optical sheets 120 may be added or deleted within the technical scope of the embodiment, but is not limited thereto.

The backlight unit 130 may include light sources 20 and 30, a light guide plate 10 for generating side incident light from the light source to the front, and a reflective sheet 39 disposed under the light guide plate 10. .

A bottom cover (not shown) for accommodating the backlight unit 130 may be provided.

The light source includes at least one light emitting diode 20 and a module substrate 30 on which the light emitting diode 20 is mounted.

The light emitting diode 20 may be a colored LED such as a red LED, a blue LED, a green LED, or a white LED, but is not limited thereto.

The module substrate 30 is made of a metal core PCB, FR-4 PCB, general PCB, etc., it can be variously changed within the technical scope of the embodiment.

The light guide plate 10 may be embodied in one or more of the first to thirteenth embodiments described above.

According to the exemplary embodiment, the patterns formed in the dark region and the hot spot region are different from each other in the light incident portion of the light guide plate 10, thereby increasing the light uniformity of the light guide plate 10.

The embodiment has the effect of reducing the luminance deviation between the light incident portion and the light portion of the light guide plate 10.

According to the embodiment, the problem of dark part generation of the backlight unit 130 may be improved, and thus, the arrangement interval of the light emitting diodes 20 may be widened, thereby reducing the manufacturing cost by reducing the number of light emitting diodes 20.

Therefore, the light efficiency and uniformity of the backlight unit 130 may be improved, and the brightness of the display device 100 having the backlight unit 130 may be improved.

The present invention has been described above with reference to preferred embodiments thereof, which are merely examples and are not intended to limit the present invention. Those skilled in the art to which the present invention pertains do not depart from the essential characteristics of the present invention. It will be appreciated that various modifications and applications are not possible that are not illustrated above. For example, each component shown in detail in the embodiment of the present invention may be modified. And differences relating to such modifications and applications will have to be construed as being included in the scope of the invention defined in the appended claims.

1 is a plan view illustrating an arrangement of a light guide plate and a light source.

2 and 3 are plan views showing a pattern of a bottom surface of the light guide plate according to the first embodiment and a perspective view of the light guide plate.

FIG. 4 is a cross-sectional view of the light guide plate according to the first embodiment taken along the line II ′ of FIG. 2.

5 is a cross-sectional view of a light guide plate according to a second embodiment.

6 is a plan view illustrating an example of a second pattern of the light guide plate according to the third embodiment.

7 is a plan view illustrating another example of the second pattern of the light guide plate according to the fourth embodiment.

8 is a plan view illustrating still another example of the second pattern of the light guide plate according to the fifth embodiment.

9 is a plan view illustrating another example of a second pattern of the light guide plate according to the sixth embodiment.

10 is a plan view illustrating a bottom surface of the light guide plate according to the seventh embodiment.

11 is a plan view illustrating a portion of a bottom surface of the light guide plate according to the eighth embodiment.

FIG. 12 is a cross-sectional view taken along the line II-II 'of FIG. 11.

FIG. 13 is a cross-sectional view taken along the line II-II 'of FIG. 11 according to the ninth embodiment.

14 is a plan view illustrating a bottom surface of the light guide plate according to the tenth embodiment.

15 is a plan view illustrating a portion of a lower surface of the light guide plate according to the eleventh embodiment.

16 is a plan view illustrating a portion of a lower surface of the light guide plate according to the twelfth embodiment.

17 is a plan view illustrating a portion of a lower surface of the light guide plate according to the thirteenth embodiment.

18 is a perspective view illustrating a mold for manufacturing light guide plates according to an embodiment.

19 is an exploded perspective view illustrating a display device including a light guide plate according to an embodiment.

Claims (26)

A light incident surface on which light is incident; A lower surface formed near the light incident surface and including a second pattern for changing a direction of the incident light; And A light guide plate comprising an upper surface for emitting the light. The method of claim 1, The light guide plate is formed on the lower surface further comprises a first pattern for changing the direction of the incident light. The method of claim 2, A light guide plate including a portion of the lower surface from a tangent of the light incident surface and the lower surface, and including at least one first region in which the second patterns are formed, wherein the first pattern is formed on the lower surface except the first region. The method of claim 3, The first region is a light guide plate of polygonal or semicircular shape having one side of the tangent line. The method of claim 2, The first pattern includes a prism pattern formed in a direction perpendicular to a direction of light incident perpendicularly to the light incident surface. The method of claim 1, The second pattern is a light guide plate including a prism pattern formed in a direction perpendicular to the direction of light incident perpendicularly to the light incident surface. The method of claim 1, The second pattern is a light guide plate including a dot pattern. The method of claim 2, The light distribution plate of which the distribution density of the second pattern is larger than the distribution density of the first pattern. The method of claim 1, The light guide plate has a constant spacing of the second patterns. The method of claim 1, The light guide plate of the second pattern is wider as the distance from the light incident surface. The method of claim 1, The light guide plate of the second pattern is narrower as the distance from the light incident surface. The method of claim 1, At least one first region including a portion of the lower surface from a tangent of the light incident surface and the lower surface, the second patterns being formed; And At least one second region in which a third pattern is formed between the first regions, A light guide plate having a first pattern formed on the lower surface except for the first region and the second region. The method of claim 12, The second region is formed on the light incident surface, and the light is incident through the second region. The method of claim 12, The second region is a light guide plate including a groove formed in the light incident surface. The method of claim 1, The second region is a light guide plate made of a scattering pattern layer formed on the light incident surface corresponding to the light source. A light source for generating light; And And a light guide plate including a light incident surface on which the light is incident, a lower surface including a second pattern for changing a direction of the incident light in first regions adjacent to the light incident surface, and an upper surface to emit the light. The method of claim 16, The backlight assembly further comprises a first pattern formed on the lower surface to change the direction of the incident light. The method of claim 16, The backlight assembly further comprises a reflective sheet disposed under the light guide plate. The method of claim 16, The light source includes at least one light emitting diode, wherein the light emitting diode is disposed between the first regions. The method of claim 16, The first region may have a polygonal or semicircular shape having a tangent between the light incident surface and the bottom surface. The method of claim 17, The first pattern includes a prism pattern formed in a direction perpendicular to a direction of light incident perpendicularly to the light incident surface. The method of claim 16, The second pattern includes a prism pattern formed in a direction perpendicular to a direction of light incident perpendicularly to the light incident surface, and the distribution density of the second pattern is greater than the distribution density of the first pattern. The method of claim 16, The second pattern includes a dot pattern. The method of claim 16, Further comprising at least one second region having a third pattern formed between the first region, And a first pattern formed on an entire surface of the lower surface of the substrate except for the first region and the second region. The method of claim 24, The third pattern is a backlight assembly consisting of a dot pattern. The method of claim 16, And a scattering pattern layer formed on the light incident surface to correspond to the light source between the first regions.

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