KR100786384B1 - Optical sheet and back light assembly of luquid crystal display equipped with the prism sheet - Google Patents

Abstract

An optical sheet and a backlight assembly of an LCD comprising the same are provided to improve the structure of the optical sheet to improve viewing angle and brightness so as to make the optical sheet function as a prism sheet and a diffusion sheet. A structured surface(620) is formed at a location facing a main surface(610), wherein the structured surface has a winding portion. The structured surface includes peaks(622) and valleys(624), which are defined according to relative height difference from a reference surface. A convex portion(625) is protruded in each of the valleys. The convex portion is gradually thicker from an edge portion toward a center portion thereof.

Description

Optical sheet and back light assembly of luquid crystal display equipped with the prism sheet

1 is a cross-sectional view showing the configuration of a conventional liquid crystal display device.

2 and 3 are cross-sectional views and photographs of the prism sheet shown in FIG.

4 is a photograph of the diffusion sheet shown in FIG. 1.

5 is a photograph of a light diffusing sheet according to an embodiment of the present invention.

6 is a perspective view showing an optical sheet according to an embodiment of the present invention.

7 is a diagram for describing another optical sheet according to the embodiment of the present invention in another method.

8 is a plan view showing an optical sheet according to an embodiment of the present invention.

9 is a view for explaining optical characteristics of the optical sheet according to the embodiment of the present invention.

10 is a view for explaining a cross-sectional configuration of an optical sheet according to an embodiment of the present invention.

11 is a view for explaining various embodiments of the convex portion according to the present invention.

12 and 13 are views for explaining another embodiment of the structured surface in the optical sheet of the present invention.

FIG. 14 is a diagram illustrating a configuration of a backlight assembly of a liquid crystal display according to a first embodiment of the present invention. FIG.

FIG. 15 is a diagram illustrating a configuration of a backlight assembly of a liquid crystal display according to a second exemplary embodiment of the present invention. FIG.

FIG. 16 is a diagram illustrating a configuration of a backlight assembly of a liquid crystal display according to a third exemplary embodiment of the present invention. FIG.

FIG. 17 is a view for explaining the case where two or more optical sheets are stacked and used according to the embodiment of the present invention; FIG.

The present invention relates to a backlight assembly of a liquid crystal display device, and more particularly, to an optical sheet.

Recently, various flat panel displays have been developed to reduce weight and volume, which are disadvantages of cathode ray tubes. Such flat panel displays include liquid crystal displays (LCDs), field emission displays (FEDs), plasma display panels (PDPs), and organic luminescence displays (OLEDs). In order to improve the display quality and to make a large screen for the same flat panel display device, studies are being actively conducted.

In particular, the liquid crystal display (LCD) has been gradually improved due to the results of active research of high power and viewing angle, which has been pointed out as a disadvantage thereof.

Unlike other display devices, the liquid crystal display is not a light emitting material that emits light, but a light emitting material that displays light on the screen by controlling the amount of light from the outside. A separate device for irradiating light, that is, a backlight assembly, is essential.

The backlight assembly includes a mold frame in which a storage space is formed, a reflection sheet installed on a base surface of the storage space to reflect light toward the liquid crystal display panel, a light guide plate installed on an upper surface of the reflection sheet to guide light, and sidewalls of the light guide plate and the storage space. A lamp unit disposed between and emitting light, optical sheets stacked on an upper surface of the light guide plate for diffusing and condensing light, and an area extending from a predetermined position of the edge of the liquid crystal display panel to the side of the mold frame Consists of a top chassis covering the.

Here, the optical sheets include a diffusion sheet for diffusing light, a prism sheet for condensing the light diffused and stacked on the upper surface of the diffusion sheet, and transferring the light to the liquid crystal display panel, and a protective sheet for protecting the diffusion sheet and the prism sheet. It is composed.

1 is a cross-sectional view showing the configuration of a conventional liquid crystal display device.

Referring to FIG. 1, a conventional liquid crystal display device 60 includes a backlight assembly 50 for generating light and an upper side of the backlight assembly 50, and receives light from the backlight assembly 50 to receive an image. A display unit 40 for displaying is included.

In detail, the backlight assembly 50 includes a lamp unit 51 for generating light and a light guide unit for guiding the light generated by the lamp unit 51 to the liquid crystal display panel 10.

In addition, the display unit 40 includes the liquid crystal display panel 10, an upper polarizing plate 30 positioned above and below the liquid crystal display panel 10, and a lower polarizing plate 20. The liquid crystal display panel 10 includes a TFT substrate on which electrodes are formed, color filter substrates 11 and 12, and a liquid crystal layer (not shown) injected between the TFT substrate and the color filter substrates 11 and 12. .

In detail, the lamp unit 51 includes a lamp 51a for generating light and a lamp reflector 51b surrounding the lamp 51a. Then, the light generated from the lamp 51a is incident to the light guide plate 52 side, which will be described later, and the lamp reflector 51b reflects the light generated from the lamp 51a to the light guide plate 52 side, thereby providing the light guide plate 52. It serves to increase the amount of light incident on the.

The light guiding unit includes a reflecting plate 54, a light guiding plate 52, and optical sheets 53, and the light guiding plate 52 is provided at one side of the lamp unit 51 to receive light from the lamp unit 51. Serves as a guide.

In addition, the lower portion of the light guide plate 52 is provided with a reflector plate 54 for reflecting light leaked from the light guide plate 52 back to the light guide plate 52 side.

Meanwhile, a plurality of optical sheets 53 are provided on the light guide plate 52 to improve the efficiency of the light guided by the light guide plate 52. Specifically, the optical sheet is composed of a diffusion sheet 53a, a prism sheet 53b, and a protective sheet 53c, and is sequentially stacked on the light guide plate 52.

In detail, the diffusion sheet 53a scatters the light incident from the light guide plate 52 to even the luminance distribution of the light.

In addition, the prism sheet 53b has a triangular prism repeatedly formed on an upper surface thereof, and collects the light diffused by the diffusion sheet 53a in a direction perpendicular to the plane of the liquid crystal display panel 10. Accordingly, most of the light passing through the prism sheet 53b proceeds perpendicularly to the plane of the liquid crystal display panel 10 to have a uniform luminance distribution.

In addition, the protective sheet 53c provided on the prism sheet 53b serves to protect the surface of the prism sheet 53b.

2 and 3 are cross-sectional views and photographs of the prism sheet shown in FIG. 1, and FIG. 4 is a photograph of the diffusion sheet shown in FIG. 1.

2 to 4, the conventional prism sheet 100 includes a body portion 110 into which light diffused by a light guide plate and a diffusion sheet is first introduced, and an isosceles triangular pillar to allow the diffused light to be uniformly progressed. It is composed of a protrusion 120 of the shape, the protrusion 120 is linearly arranged in a stripe shape on the body portion (110).

In addition, the isosceles triangular pillar-shaped protrusion 120 has a pitch of 10 μm to 100 μm, and the angle of the vertex angle α of the triangular pole is acute, and the viewing angle is narrowed instead of increasing luminance.

In addition, the diffusion sheet as shown in FIG. 4 scatters the light incident from the light guide plate 52 to uniform the luminance distribution of the light, thereby allowing the light to flow into the prism sheet 100.

On the other hand, as shown in Figure 2 and 3, when the projection 120 in the shape of a triangular pillar is installed toward the front, that is, when the projection toward the liquid crystal display panel flows through the body portion 110 The diffused light is refracted forward and collected, but the light incident on the inclined surface of the protrusion is lost due to total internal reflection without being contributed to the improvement of the brightness of the front.

In order to solve this problem, it is proposed to configure the triangular shape of the prism sheet 100 into an isosceles shape or to arrange the prism sheet in reverse so that the protrusion of the prism sheet 100 faces the light guide plate. It is very difficult to achieve the desired result in both and the viewing angle.

The present invention has been proposed to solve the above problems, and an object of the present invention is to propose a light diffusing sheet capable of serving as a prism sheet and a diffusion sheet, and a backlight assembly of a liquid crystal display device having the optical sheet.

In addition, an object of the present invention is to propose an optical sheet capable of improving a viewing angle and luminance and a backlight assembly of a liquid crystal display device having the optical sheet.

Optical sheet according to an embodiment of the present invention for achieving the above object is a main surface; And a spherical surface formed to face the main surface and having a predetermined curvature, wherein the structured surface includes peaks and valleys according to relative height differences from a predetermined reference surface. ), And the convex portion protruding a predetermined thickness is formed in the bone region.

In addition, the optical sheet according to the present invention comprises a main surface; A structured surface disposed to face the main surface and arranged with an array of prisms for refracting or reflecting incident light; And a convex portion formed on a lower portion of the structured surface and protruding a predetermined thickness.

The backlight assembly of the liquid crystal display according to the embodiment of the present invention includes a lamp for generating light; A light guide plate for guiding light generated by the lamp; And an optical sheet disposed adjacent to the light guide plate, the optical sheet for diffusing or condensing light incident from the light guide plate, wherein the optical sheet is formed at a surface opposite to the main surface to which light enters, Comprising a structured surface formed to have a predetermined curvature, the structured surface includes a peak (valley) according to the relative height difference from a predetermined reference surface (valley), the bone region is formed with a predetermined thickness protruding A convex portion is formed.

According to the optical sheet and the backlight assembly of the liquid crystal display device provided with the optical sheet as proposed, there is an advantage that can perform both the role of the conventional prism sheet and the diffusion sheet.

In addition, there is an advantage that the viewing angle and brightness is greatly increased.

5 is a photograph of a light diffusing sheet according to an embodiment of the present invention, FIG. 6 is a perspective view showing an optical sheet according to an embodiment of the present invention, and FIG. 7 describes another optical sheet in another embodiment of the present invention. It is a figure for following.

First, referring to FIG. 5, a cross section of an optical sheet according to an embodiment of the present invention has a triangular shape or a prism shape similar to that of a conventional prism sheet, and has a convex part at a predetermined portion of the prism shape. It is characterized by that. The convex portions may be irregularly formed in an arbitrary region, but may be aligned according to a predetermined rule.

In other words, the optical sheet of the present invention may be described as being composed of a surface into which light is introduced, a structured surface disposed at a position opposite to the first surface and having a prism array formed thereon, and a convex portion formed at the structured surface. Can be.

In addition, while the conventional prism sheet is formed of a body portion and a protrusion, an embodiment of the present invention provides a body portion into which light is first introduced, a protrusion for refracting or reflecting incident light, and scattering light to cause luminance characteristics. It is also possible that the convex portion for improving the shape is formed on any surface of the protrusion.

6 and 7, the embodiments of the present invention will be described in detail below.

In the optical sheet 600 according to the embodiment of the present invention, a main surface 610 into which light generated from a predetermined light source is introduced and formed at a position opposite to the main surface 610 are used to refract or reflect light. Included is a structured face 620 on which a prism array is formed.

In detail, the structured face 620 has a prism array formed by the first face 621 and the second face 622 extending along a predetermined axis, the first face 621 and the second face 622. ) Peaks 622 and valleys 624 are formed in the region where).

In particular, the peak 622 is formed at a position relatively higher than the main surface 610 than the valley 624, and a convex portion 625 protruding a predetermined height is formed in the peripheral region of the valley 624. .

Here, the convex portion 625 is for refracting the light incident through the main surface 610, and the incident light is injected by the convex portion 625 and the incident light is separated from the optical sheet 600 at various angles. Be sure to

The convex portion 625 is formed on at least one of the first surface 621 and the second surface 622, and is particularly formed near the valley 624.

The linear vertex edge of the valley 624 is formed to have a curvature in the region where the convex portion 625 is formed, and as shown in FIG. 5, an area around the valley 624 is predetermined. Height raised embossing is formed.

Regarding the position where the convex portion 625 is formed, it may be disclosed in more detail with reference to FIG. 8.

An optical sheet according to an embodiment of the present invention, with reference to FIG. 6, a prismatic array formed by a main surface, a first surface and a second surface, a structured surface having the prism array, and a valley formed on the structured surface. It is disclosed that peracids are included. Meanwhile, another representation of the optical sheet according to the embodiment of the present invention will be described with reference to FIG. 7.

In the optical sheet 700 according to the embodiment of the present invention, a body portion (substrate, 710) to which light is introduced, a protrusion (720) formed on the upper surface of the body portion (710) to refract the light, and A convex portion 730 is formed at a predetermined position of the protrusion portion 720 to increase light condensing or diffusing efficiency.

In detail, the protruding portion 720 and the convex portion 730 are formed on the first surface of the body portion 710, and the second surface of the body portion 710 is formed flat.

The body portion 710 may include, but is not limited to, a plastic film made of polyethylene terephthalate (PET), polyethylene naphthalate (PEN), oriented polypropylene, polycarbonate, triacetate, and the like.

For example, polyester films such as Tetron® film, MELINEX® film and the like can be used as the substrate.

In addition, similar to the shape of a general prism sheet, the protrusion 720 may be provided in a triangular cross section. Although not shown in the drawing, the cross section of the protrusion 720 has an isosceles triangle shape or a triangle having predetermined curvature. The protrusion 720 may be provided to have an image.

The protrusion 720 may be made of the same material as the body 710 or coated with a transparent metal compound or synthetic resin.

In addition, when the protrusion 720 is provided such that the cross section of the protrusion 720 has a triangular shape, the protrusion 720 has two surfaces 721 and 722 for forming a triangular shape as shown in FIG. 7. In the region where the two surfaces meet, two-dimensional edges 723 and 724 are formed.

However, the protrusions 720 may be provided in a triangular shape in which the cross section is slightly distorted according to the conditions of the manufacturing process, in which case the two surfaces 721 and 722 forming the protrusions 720 may also have a slightly distorted shape. Can be.

In other words, the protrusion 720 has inclined surfaces 721 and 722 to have a predetermined angle with the surface of the body portion 710 and edges 723 and 724 formed by the surfaces 721 and 722.

Hereinafter, in order to describe the convex portion 730 in detail, an example in which the protrusions 720 have two surfaces 721 and 722 and edges 723 and 724 are formed in an area where the surfaces meet. Let's lift it.

In particular, the corner may be divided according to the position where the first surface 721 and the second surface 722 meet, and the first corner 723 and the first corner ( It may be divided into a second corner 724 formed at a lower position than the 723.

Here, the first corner 723 is located in the peak area of the prism array shape of the protrusion 720, the second corner 724 is located in the valley area of the prism array. Done.

When the convex portion 730 is positioned in the valley region of the prism array, the convex portion 730 may be provided to bend the portion of the second edge 724 more accurately.

In more detail, the convex portion 730 may be provided in a planar shape of a circle or an ellipse, and the convex portion 730 is provided in a shape in which its thickness becomes thicker from its edge toward its center.

That is, the convex portion 730, as its name, is formed convexly so that its thickness becomes thicker from its edge toward the center.

The convex portion 730 is formed such that a portion thereof overlaps with the second corner 724 constituting the protrusion 720.

Shape and size of the convex portion 730 may be provided in various ways, the position is formed may also be formed in the bone area of the protrusion 220.

The shape of the convex portion 730 and the deformation of the formation position thereof may be variously made. The light passing through the protruding portion 720 may have a moving path in various directions, and the convex portion 730 may also have its shape. This is because the condensing or diffusing efficiency can be increased even if the formation positions are varied.

In addition, when the convex portion 730 is formed on an area of the second edge 724 of the protrusion 720, the light collecting efficiency may be further improved.

In the above-described embodiment, the convex portion 730 is described as being formed on the second edge 724 region, but in another aspect, the convex portion 730 is formed on the surface 721 and 722 in the prism-shaped valley region. Are provided in a shape to allow them to be interconnected.

That is, as the convex portion 730 is formed at the position of the region where the second edge 724 is to be formed, the surfaces 721 and 722 are connected by the convex portion 730.

According to another aspect, the protrusion 720 has two or more surfaces 721 and 722 inclined at an angle from the surface of the body portion 710, and the protrusion 730 is a valley area of the protrusion 720. Intervention is formed between the planes of.

That is, in various embodiments of the present invention, a plurality of protrusions 730 having a predetermined thickness are formed on the surface of the protrusion 220, but a plurality of concave portions having a predetermined thickness are formed on the surface of the protrusion 720. Multiple can be formed. In this case, refraction or diffusion of light can also be sufficiently performed by the concave portion.

The convex portion 730 may be formed by injecting convex lenses made of a predetermined material onto the surface of the protrusion 720. For this purpose, before the protrusion 720 is hardened, a part of the lenses may be formed. To be inserted into the protrusion 720.

In this case, the lenses used to form the convex portion 730 may be made of the same material as the protrusion portion 720, and the lenses are embedded in the second corner 724 of the protrusion portion 720. It is preferable.

8 is a plan view showing an optical sheet according to an embodiment of the present invention.

A preferred shape of the convex portion 730 will be described with reference to FIG. 8.

FIG. 8 is a plan view of the protrusion 720 having the convex portion 730 formed thereon, and the preferred horizontal length (or horizontal length Lh) and the vertical length Lv for the arbitrary protrusion 730. Take a look.

Classification (Lh / Lv) Haze (%) (back → front) Transmittance (TLT,%) (back → front) Luminance gain Lh: 30 ~ 40μm Lv: 60μm 92 40 1.35

Table 1 is a result of looking at the optical characteristics of the light emitted from the backlight assembly when two sheets of the optical sheet according to the embodiment of the present invention are laminated.

In addition, the sheet used in the experiment for measuring the optical properties of the optical sheet according to the present invention was selected in size when used in the backlight assembly for a 17-inch liquid crystal display device, it is applicable to 26 inches, 32 inches, 40 inches Of course.

In the case where the horizontal length of the convex portion 730 according to the present invention has a size of 30 µm to 40 µm and a vertical length of 60 µm, when applied to the backlight assembly, the haze is 92% and the transmittance is 40%, the luminance increase rate was 1.35.

In this case, when the optical sheet according to the present invention is laminated and used with one conventional diffusion film, three optical sheets having a combination structure of an existing diffusion film, a prism film, and a protective film (for example, a prism sheet manufactured by 3M) are used. It can be seen that it has an excellent effect than when used.

9 is a view for explaining the optical characteristics of the optical sheet according to an embodiment of the present invention.

Looking at the optical characteristics of the optical sheet according to the present invention with reference to Figure 9, the convex portion 730 of the present invention may serve to scatter (scattering) the incident light, the scattered light may be present in the optical sheet It serves to compensate for defects.

That is, when a predetermined defect exists in the optical sheet, dark spots of a predetermined size are observed in the observed light, but such spots are not observed by the user by scattering light through the convex portion according to the present invention. You may not.

In addition, when the incident angle is greater than the critical angle at which total reflection of light occurs in the orphans flowing into the surface of the protrusion 720, that is, the interface between the media, total reflection occurs (that is, internal reflection occurs when the incident angle is larger than the critical angle). When the incident angle is smaller than the critical angle, the angle is refracted and passes through the protrusion 720.

As shown, the light B1 when the incident angle is larger than the critical angle is internally reflected and refracted back toward the body portion 710, and the light B2 when the incident angle is smaller than the critical angle is refracted and is separated from the protrusion 720. Departure.

The incident light B3 and B4 moving to the convex portion 730 are separated from the sheet while being scattered by the convex shape having a predetermined thickness of the convex portion 730.

10 is a view for explaining a cross-sectional configuration of an optical sheet according to an embodiment of the present invention.

As described above, the optical sheet according to the present invention has a body portion 710 forming a substrate and a protrusion portion 720 formed on one surface of the body portion 710.

The protrusion 720 is formed in a prism array or a curved shape with a predetermined size, and the curved shape is formed by convex portions formed in the protrusion 720.

Here, the vertex angle α of the protrusion 720 may be formed to have an angle in the range of approximately 95 ± 3 °, and the vertex angle α may be a vertex angle in a prism shape observed in the cross-sectional structure of the protrusion 720. It may be, it may also be defined as an angle including the convex portion formed in the protrusion 720.

As such, the vertex angle α of the protruding portion 720 may be measured by various methods, and the thickness of the convex portion may be regarded as slight compared to the size of the protruding portion 720 even when using various measuring methods. Therefore, a vertex angle may be formed in the above angular range of 95 ± 3 °.

11 is a view for explaining various embodiments of the convex portion according to the present invention.

First, the convex portion according to the present invention is formed on the prism array, which is formed by the first surface 1101 and the second surface 1102.

As shown in the cross-section of the prism array, a linear straight line is observed by the first and second surfaces 1101 and 1102, and convex portions 1110, 1120, 1130, and 1140 of various shapes according to the present invention. , 1150 is formed on the first surface 1101 or the second surface 1102.

[First embodiment of the shape of the convex portion]

The first convex portion 1110 and the second convex portion 1120 are formed on the first surface 1101 or the second surface 1102, and in particular, the first convex portion 1110 and the second convex portion ( 1120 is formed to meet at the vertex of the valley region of the prism array.

In detail, the first convex portion 1110 is formed on the first surface 1101, the second convex portion 1120 is formed on the second surface 1102, and the first convex portion ( One end of the first convex portion 1120 and one end of the second convex portion 1120 may be formed to meet at a vertex of the valley region of the prism array.

Second Embodiment of Convex Shape

A third convex portion 1130 is disclosed, and the third convex portion 1130 is formed in the valley region of the prism array, and is particularly provided in a shape surrounding the vertex of the valley region.

In detail, the third convex portion 1130 may be described as two convex portions formed to overlap each other at a vertex of the bone region, and as the third convex portion 1130 is also formed above the vertex of the valley region, The valley area where the first surface 1101 and the second surface 1102 meet has a predetermined curvature.

[Third Embodiment of Convex Shape]

A fourth convex portion 1140 formed on the first surface 1101 and a fifth convex portion 1150 formed on the second surface 1102 are disclosed, and the fourth convex portion 1140 and the fifth convex are disclosed. The portion 1150 is formed to extend from the valley region to the hill region of the prism array.

Accordingly, when the fourth convex portion 1140 and the fifth convex portion 1150 are formed, the cross section does not appear in a general prism shape, and the protrusions may be formed to have a predetermined curvature.

12 and 13 are views for explaining another embodiment of the structured surface in the optical sheet of the present invention.

First, in FIG. 12, the optical sheet has recesses formed in a predetermined depth in various shapes in a structured surface.

In detail, referring to FIG. 13, the structured surface 1320 of the optical sheet according to the present invention has a prism array shape, and the structured surface 1320 has a recess 1330 recessed to a predetermined depth. A plurality is formed.

As the concave portion 1330 is formed on the structured surface 1320, the structured surface 1320 is formed when the concave portion 1300 is formed to face an edge of the structured surface 1320. An upper portion of the recessed portion 1340 having a predetermined thickness is formed.

That is, the depression 1340 may be formed when the concave portion 1330 is disposed to face the upper surface of the structured surface 1320, as if the upper edge of the structured surface 1320 is It can also be seen that it consists of a predetermined depth recessed shape. Accordingly, the recessed portion 1340 is formed such that a portion of the upper edge of the structured surface 1320 is curved.

In detail, the concave portion 1330 may be irregularly or randomly formed on the structured surface 1320, and a plurality of concave portions 1330 may be disposed to face the upper edge of the structured surface 1320.

The concave portion 1330 is provided in a shape recessed to a predetermined depth on the surface of the structured surface 1320, and as the concave portion 1330 is formed in a plurality, the structured surface 1320 has a prism array shape. May appear in some distorted shape.

The concave portion 1330 and the recessed portion 1340 are scattered by the beams refracted by the structured surface 1320, thereby scattering the beams leaving the structured surface 1320. Is improved.

FIG. 14 is a diagram illustrating a configuration of a backlight assembly of a liquid crystal display according to a first embodiment of the present invention.

Referring to FIG. 14, the backlight assembly 1400 of the liquid crystal display according to the exemplary embodiment of the present invention includes a lamp unit 1440 for generating light and light generated by the lamp unit 1440 toward the liquid crystal display panel. A light guiding unit for guiding is included.

The lamp unit 1440 according to the exemplary embodiment of the present invention includes a lamp 1441 for generating light and a lamp reflector plate 1442 surrounding the lamp 1441. Light emitted from the lamp 1442 is incident on the light guide plate 1420.

In this case, the lamp reflection plate 1442 reflects the light generated from the lamp 1442 toward the light guide plate 1420, thereby increasing the amount of light incident on the light guide plate 1420.

In addition, the light guide unit according to the embodiment of the present invention includes a reflecting plate 1430, the light guide plate 1420 and the optical sheet 1410, the light guide plate 1420 is provided on one side of the lamp unit 1440 is the lamp It guides the light generated from the unit 1440 to be moved to the liquid crystal display panel.

In addition, a reflector 1430 is provided below the light guide plate 1420 to reflect the light leaked from the light guide plate back to the light guide plate 1420.

Meanwhile, an optical sheet 1410 is disposed above the light guide plate 1420 to improve optical characteristics of light moved by the light guide plate 1420, and only an optical sheet 1410 according to an exemplary embodiment of the present invention is illustrated. However, a diffusion sheet, a prism sheet, or a protective sheet may be further provided.

However, since only the optical sheet 1410 according to the embodiment of the present invention can fully expect the role of the conventional diffusion sheet or the prism sheet, even when used alone, excellent effects in terms of viewing angle and luminance can be obtained.

FIG. 15 is a diagram illustrating a configuration of a backlight assembly of a liquid crystal display according to a second exemplary embodiment of the present invention.

Referring to FIG. 15, the backlight assembly 1500 of the liquid crystal display according to the present invention includes a lamp unit 1540 for generating light and a diffusion for guiding light generated by the lamp unit 1540 toward the liquid crystal display panel. Unit is included.

The lamp unit 1540 includes a lamp 1541 for generating light, and a lamp reflector 1542 surrounding the lamp 1541. Light emitted from the lamp 1541 is incident on the light guide plate 1520. For reference, although the light guide plate 1520 may also be referred to as a diffusion plate, the light guide plate 1520 will be described as a light guide plate in the present invention.

The lamp reflector 1542 reflects the light generated from the lamp 1541 toward the light guide plate 1520, thereby increasing the amount of light incident to the light guide plate 1520.

In addition, the light diffusion plate 1520 and the optical sheet 1510 are included in the diffusion unit. The light guide plate 1520 is disposed above the lamp unit 1540 to diffuse light generated from the lamp unit 1540 to guide the light guide plate to be moved to the liquid crystal display.

In addition, since the light guide plate 1520 is disposed above the lamp unit 1540, light leaked from the light guide plate 1520 may be guided back to the light guide plate 1520 by the lamp reflection plate 1542.

In addition, an optical sheet 1510 is disposed above the light guide plate 1520 to increase the optical efficiency of light moved by the light guide plate 1520, and the optical sheet 1510 forms a base as described above. It consists of a body portion, a protrusion formed on the body portion and a convex portion formed on the protrusion.

FIG. 16 is a diagram illustrating a configuration of a backlight assembly of a liquid crystal display according to a third exemplary embodiment of the present invention.

Referring to FIG. 16, the backlight assembly 1600 of the liquid crystal display according to the present invention includes a lamp unit 1640 including a lamp 1641 and a lamp reflecting plate 1641 for generating light, and the lamp unit 1640. A light guide unit for guiding light generated by the light toward the liquid crystal display panel is included.

As described above, the light guide unit includes the reflective plate 1630, the light guide plate 1620, and the optical sheet 1610.

However, according to the embodiment of the present invention, the protrusions and the convex portions of the optical sheet 1610 having various shapes are formed to face the light guide plate 1620.

That is, the optical sheet 1610 is provided so that light passing through the light guide plate 1620 is first introduced into the protrusions and the convex portions of the optical sheet 1610 and the light refracted by the protrusions and the convex portions moves to the body portion. do.

In FIG. 16, although the protrusions and convex portions of one optical sheet 1610 are formed downward, two or more optical sheets 1610 according to an embodiment of the present invention are stacked, and the optical sheet 1610 is stacked. Can be configured such that both the convex portion and the protruding portion thereof face the light guide plate 1620 or only a portion thereof.

17 is a view for explaining the case where two or more optical sheets are stacked and used according to the embodiment of the present invention.

As described above, each optical sheet used for stacking includes a body portion into which light first flows, a protrusion formed on the body portion and having a substantially triangular cross section, and a convex portion that can be formed in any region of the protrusion. Have

In addition, a plurality of optical sheets 1701, 1702, and 1703 according to an embodiment of the present invention may be stacked and used.

As illustrated in FIG. 17, two or more optical sheets 1701, 1702, and 1703 according to various embodiments of the present invention are stacked on the backlight assembly 1700 of the liquid crystal display according to the fourth embodiment of the present invention. Can be used.

According to the optical sheet and the backlight assembly of the liquid crystal display device provided with the optical sheet as proposed, there is an advantage that can perform both the role of the conventional prism sheet and the diffusion sheet.

In addition, there is an advantage that the viewing angle and brightness is greatly increased.

Claims (16)

Major surface; And A structured surface formed to face the main surface and formed to have a predetermined curvature; The structured surface includes a peak and a valley according to a relative difference in height from a predetermined reference surface, and the valley region has a convex portion protruding a predetermined thickness. The method of claim 1, And the convex portion gradually increases in thickness from its edge toward its center. The method of claim 1, A predetermined edge is formed by a plurality of faces constituting the structured face, The convex portion is provided with a shape to bend a portion of the edge optical sheet. Major surface; A structured surface disposed to face the main surface and arranged with an array of prisms for refracting or reflecting incident light; And And a convex portion formed on a lower portion of the structured surface to protrude a predetermined thickness. The method of claim 4, wherein Incident light is introduced through the main surface, And the convex portion disperses when the incident light is separated from the sheet. The method of claim 4, wherein The convex portion is formed in plurality on the lower portion of the structured surface, And a plurality of convex portions are arranged irregularly. A protrusion having a body portion forming a substrate and an array of prisms formed on one surface of the body portion, The protrusion is made of a bone and a mountain classified according to the relative height difference from the body portion, The valley is formed with a convex portion protruding a predetermined thickness is formed optical sheet. The method of claim 7, wherein The protrusion of the protrusion includes an edge formed by a plurality of surfaces, And the convex portion is provided in a shape of bending the corners. The method of claim 7, wherein In the cross-sectional shape of the sheet, the vertex angle (α) of the protrusion is formed to have an angle in the range of 95 ± 3 °. The method of claim 7, wherein The light is separated from the protrusion, The sheet is diffused or scattered by the convex portion. An optical sheet in which a beam is refracted through a structured surface, And the concave portion having a concave shape is formed in the structured surface. The method of claim 11, And a plurality of concave portions formed to face the upper edge of the structured surface. The method of claim 11, And a plurality of depressions having a predetermined depth formed in the upper edge region of the structured surface. A lamp for generating light; A light guide plate for guiding light generated by the lamp; And An optical sheet disposed adjacent to the light guide plate for diffusing or condensing light incident from the light guide plate; The optical sheet is formed of a major surface on which light is introduced, and a structured surface formed at a position opposite to the main surface and formed to have a predetermined curvature, The structured surface includes a peak and a valley according to a relative difference in height from a predetermined reference surface, and a convex portion protruding a predetermined thickness is formed in the valley area. . The method of claim 14, A predetermined edge is formed by a plurality of faces constituting the structured face, And the convex portion is provided in a shape of bending a portion of the corner. A lamp for generating light; A light guide plate for guiding light generated by the lamp; And An optical sheet disposed adjacent to the light guide plate for diffusing or condensing light incident from the light guide plate; The optical sheet has a body portion forming a substrate and a protrusion having a prism array formed on one surface of the body portion, And wherein the protrusion is formed of a valley and a hill classified according to a relative difference in height from the body, and the valley is formed with a protrusion having a predetermined thickness.

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