KR20050121523A - Optical film, and backlight assembly and liquid crystal display having the same - Google Patents

Abstract

Disclosed are an optical film for improving the luminance characteristic of light, a backlight assembly and a liquid crystal display device having the same. The light guide plate guides the path of the light emitted from the lamp and emits the first light, and the optical film is disposed on a surface opposite to the upper surface of the light guide plate, and the first light is emitted through the plurality of prism mountains discontinuously formed in one direction. It condenses and diffuses and exits 2nd. As a result, by forming a discontinuous prism acid on the base, the front luminance can be increased with only one film.

Description

Optical film, backlight assembly and liquid crystal display device having the same {OPTICAL FILM, AND BACKLIGHT ASSEMBLY AND LIQUID CRYSTAL DISPLAY HAVING THE SAME}

The present invention relates to an optical film, a backlight assembly and a liquid crystal display device having the same, and more particularly, to an optical film for improving the brightness characteristics of light, and a backlight assembly and a liquid crystal display device having the same.

In general, an optical film, in particular a prism film, is used as a component of a display device, for example, a rear light source for a liquid crystal display, a film for improving brightness, a light reflecting film, and the like. The optical film refers to a film in which an ultraviolet curable resin is laminated on the base film using a polyester film provided with adhesiveness on at least one side thereof as a base film.

The prism film is used for converging the direction of light in the vertical direction to make the front luminance higher.

1 is a perspective view of a backlight assembly having a general prism film. In particular, a backlight assembly having an isosceles triangular prism film shown in FIG. 10 of US Patent No. 5,600,455 is shown.

Referring to FIG. 1, light generated from the lamp 2 is incident to the diffuser plate 4 through the light guide plate 3 and the reflective sheet 1, and the light passing through the diffuser plate 4 has two prisms. Pass through the film. The prism film 5 is a prism film in which isosceles triangular prisms are continuously arranged side by side along one side direction of the plane from which light is emitted, for example, the x-axis direction, and along the y-axis direction located thereon. The prism films in which the isosceles triangle prisms are continuously arranged side by side may be arranged to converge the light in the x and y-axis directions in the front direction, that is, the z-axis direction, to increase the front luminance.

However, when two prism films are used to increase the front brightness, there is a problem in that it is disadvantageous in price and light weight. In addition, when using a single prism film, there is a problem that the front brightness is lowered.

Accordingly, the technical problem of the present invention is to solve such a conventional problem, and an object of the present invention is to provide an optical film having a prism acid having a discontinuous pattern for increasing the front luminance with only one film.

In addition, another object of the present invention is to provide a backlight assembly having the optical film described above.

Further, another object of the present invention is to provide a liquid crystal display device having the above-described backlight assembly.

Optical film according to one feature for realizing the above object of the present invention, the base; And a cross section protruding in one direction on one surface of the base, and cut in a direction parallel to the surface of the base, having a semi-wire shape, and cut perpendicularly to the surface of the base in a long axis direction of the semi-wire shape. It has a round shape in cross section, and includes a plurality of optical characteristic improving structures that condense and diffuse light emitted from the outside.

Optical film according to another feature for realizing the above object of the present invention, the base formed with a predetermined thickness on the X-Y plane; And protrude at a different height toward the X-axis on one surface of the base, the cross section cut the XZ plane to the cutting plane defines a round shape of a certain curvature to diffuse the light provided from the outside, and the YZ plane to the cutting plane The cut cross section includes a plurality of optical characteristic enhancement structures that condense and emit light provided from the outside while defining a triangular shape.

Optical film according to another feature for realizing the above object of the present invention, the base formed on the X-Y plane; And protrude at a different height toward the X-axis on one surface of the base, the cross section cut the XZ plane to the cutting plane defines a round shape of a certain curvature to diffuse the light provided from the outside, and the YZ plane to the cutting plane The cut cross section includes a plurality of optical characteristic enhancing structures that condense and diffuse light emitted from the outside while defining a full triangle shape.

According to another aspect of the present invention, there is provided a backlight assembly comprising: a lamp for emitting light; And an optical film which is emitted to the other side by improving the characteristics of light provided from one side through a plurality of optical characteristic enhancement structures formed to protrude in one direction.

A liquid crystal display device for realizing another object of the present invention described above comprises: a light source for generating light; A liquid crystal panel displaying an image using a potential difference applied to the liquid crystal layer; And an optical film having a plurality of optical characteristic enhancement structures protruding in one direction, and including an optical control unit for adjusting the characteristics of the light generated from the light source to provide the liquid crystal panel.

According to the optical film, the backlight assembly and the liquid crystal display device having the same, the front brightness can be increased by only one film by forming a discontinuous prism acid on the base.

Hereinafter, with reference to the accompanying drawings, it will be described in detail the present invention.

2 is a perspective view of a backlight assembly according to an embodiment of the present invention.

Referring to FIG. 2, the backlight assembly 100 according to the present invention includes a light generating unit 110, a light guide plate 120, an anti-prism film 130, and a reflective sheet 140.

The light generator 110 may include a lamp 112, a lamp cover 114, first and second wires 115 and 116, and a connector 118 to supply power voltages provided through the connector 118. The light is applied to the lamp 112 through the first and second wires 115 and 116, respectively. The lamp cover 114 covers a portion of the reflective sheet 140 through one end while surrounding the lamp 112.

The light guide plate 120 is disposed between the anti-prism film 130 and the reflective sheet 140, and a plurality of light guide plates 120 extended in a direction perpendicular to the direction in which the lamp 112 extends on a surface opposite the reflective sheet 140. The prisms are formed to guide the path of the light provided from the light generator 110 and the path of the light provided from the reflective sheet 140 to the anti-prism film 130.

In particular, in the case of the prism formed on the light guide plate 120, the top surface of the prism close to the lamp 112 is preferably a round or parabolic shape. For example, the prism close to the lamp 112 preferably has a parabolic shape with a maximum radius of curvature, and has a parabolic shape with a radius of curvature gradually decreasing away from the lamp 112.

The anti-prism film 130 is disposed on the upper portion (or the emitting surface) of the light guide plate 120 to condense and diffuse the light guided by the light guide plate 120 to control brightness characteristics of the light. The anti-prism film 130 has a shape formed discontinuously such that a plurality of prisms face the exit surface of the light guide plate. The direction in which the prisms formed in the inverse prism film 130 are formed is substantially perpendicular to the direction in which the prisms formed in the lower (or reflective surface) of the light guide plate 120 are formed. In addition, the direction in which the prisms formed in the anti-prism film 130 are formed is substantially parallel to the direction in which the lamp 112 extends.

The reflective sheet 140 is disposed under the light guide plate 120 to reflect the light leaked from the light guide plate 120 to the light guide plate 120. Although the reflective sheet of the flexible type is shown in the present invention, a rigid reflective plate is also possible.

In this way, a plurality of prisms formed perpendicular to the longitudinal direction of the lamp 112 are formed on the rear surface of the light guide plate employed in the edge type backlight assembly, that is, the light reflection surface opposite to the reflective sheet, and the prism close to the lamp 112. By rounding the top of, it is possible to suppress the occurrence of bright lines in the corner portion of the light incident portion of the light guide plate.

FIG. 3 is a diagram schematically illustrating the light guide method using the light guide plate of FIG. 2.

2 and 3, the first light I provided from the lamp 112 is incident on the incident surface of the light guide plate 120, and the path of the incident first light is first guided to guide the light guide plate. The light exits through the light exit surface of 120).

A portion of the first guided first light leaks through the reflective surface of the light guide plate 120. The second light II, which is part of the leaked light, is first diffused through the light guide plate 120 by the reflective sheet 140 and is emitted through the light exit surface of the light guide plate 120 through a second guide process. The third light (III), which is the remainder of the leakage light, is second diffused and transmitted through the light guide plate 120 by the reflective sheet 140 and exits through the light exit surface of the light guide plate 120 through a third guide process. . The degree of diffusion by the second diffusion transmission is greater than the degree of diffusion by the first diffusion transmission.

The reflective surface of the light guide plate 120 that receives the first diffused light is an area close to the lamp 112. The reflective surface of the light guide plate 120 that receives the second diffused light is a region far from the lamp 112.

FIG. 4 is a view for explaining the light guide plate of FIG. 2. In particular, FIG. 4 is a perspective view of a portion of the light guide plate to remove the wedge type light guide plate.

As shown in FIGS. 2 and 4, the light guide plate 120 includes a light incident portion 121 closest to the lamp 112, an opposing portion 122 facing the light incident portion 121, and the reverse prism. Having a hexahedron shape consisting of a light exit portion 123 facing the film 130, a bottom portion 124 facing the reflective sheet 140, a first side portion 125 and a second side portion 126, The light provided from the lamp 112 is received through the light incident part 121 to guide the light path, and the guided light is emitted through the light exit part 123. Here, the partial region of the light guide plate 120 is removed for convenience of description.

Light incident part 121 is a surface closest to the lamp 112, the lower side has a straight line, the upper side has a round prism mountain shape, defined by the distance between the lower side and the valley of the prism acid It serves as a light incident part for receiving the light provided from the lamp 112 with a first height (T1) to be.

Opposite portion 122 is a surface closest to the lamp 112, the lower side has a straight line, the upper side has a prism acid, the second height defined by the distance between the valley of the lower side and the prism It has the T2 and opposes the light incident part 121. In this case, since the light guide plate 120 is a wedge type, the second height T2 is smaller than the first height T1.

The light exit part 123 is formed in a quadrangular shape having first to fourth end sides, in particular, the first end side is in contact with the lower side of the light incident part 121, and the second end side is opposite to the opposite side ( A third side and a third end side of the first side and a second side portion 125 and 126, respectively; Guided light is provided to the anti-prism film 130.

The bottom part 124 opposes the reflective sheet 140 disposed at the bottom while connecting the upper side of the light incident part 121 and the upper side of the opposing part 112 and is reflected by the reflective sheet 140. The input light. The bottom portion 124 is formed with a plurality of prisms extending perpendicular to the longitudinal direction of the lamp 112, the vertices of the prism acid is preferably 100 to 120 degrees.

The prism of any of the prisms adjacent to the lamp 112 has a round cross section. The light guide plate 120 having the rounded prism may be manufactured at the time of injection molding, and after forming the light guide plate 120 having the prism, a separate round treatment may be performed only at the top of a desired region. It may also be produced by incorporation of a single piece with a second piece having a rounded prism.

The first side portion 125 is formed in a quadrangular shape having first to fourth end sides, in particular, the first end side is in contact with one side of the light incident part 121, and the second end side is opposite to the opposite side ( The third end side is in contact with one side of the bottom part 124, and the fourth end side is in contact with one side of the light exiting part 123.

In addition, the second side portion 126 is formed in a quadrangular shape consisting of first to fourth end sides, in particular, the first end side is in contact with the other side of the light incident portion 121, the second end side is opposite In contact with the other side of the portion 122, the third end side is in contact with the other side of the light exit portion 123, the fourth end side is in contact with the other side of the bottom portion 124.

In the drawing, although the formation height of the valleys and the formation heights of the tops of the plurality of prisms having a triangular prism shape are the same, and the two inclination angles in the same prism are the same, the formation heights of the valleys and / or the tops of the plurality of prisms differ. The two inclination angles in the same prism may be configured differently.

Although the bone defining the prism is sharp, the bone defining the prism may be rounded.

Although the direction in which the bone defining the prism is formed is perpendicular to the direction in which the lamp 112 extends, it may be formed to have a predetermined angle with the direction in which the lamp 112 extends.

Although the bone defining the prism is shown to form a straight line when viewed on the light exiting part 124, the bone defining the prism may be formed to have a curved line.

As described above, by providing a light condensing function to the rear surface of the light guide plate, the performance of the backlight can be improved. In addition, by disposing an anti-prism film having a light condensing function and a diffusing function on the upper part of the light guide plate, wider visibility and better appearance quality can be ensured.

DETAILED DESCRIPTION Various examples of inverse prism according to the present invention will now be described with reference to the accompanying drawings.

<Example-1 of a reverse-prism film>

FIG. 5 is a perspective view of a reverse prism film according to an embodiment of the present invention, and FIG. 6 is a plan view of a portion of the reverse prism film of FIG. 5 described above, and FIGS. 7A and 7B of FIG. These are cross-sectional views cut by the cutting lines I-I 'and II-II', respectively.

5 to 7B, an anti-prism film 130 according to an embodiment of the present invention is discontinuous in one direction on a base (or base film) 132 and one surface of the base film 132. It includes a plurality of optical characteristic enhancement structure 134 formed as.

One surface of the base film 132 on which the optical characteristic enhancement structure 134 is formed faces the exit surface of the light guide plate 120, and the other surface of the base film 132 on which the optical characteristic enhancement structure 134 is not formed is a panel. It is preferable to face the side. The base 132 and the optical characteristic improving structure 134 may be made of the same material having the same refractive index, or may be made of different materials having different refractive indices.

A plurality of optical characteristic enhancement structures 134 are in contact with the base film 132 having a semi-streamline shape. The optical characteristic improving structure 134 has a major axis in the x-axis direction and a minor axis in the y-axis direction. The semi-wired shape defines a closed curve that has a long axis and a short axis and gradually narrows toward both ends and widens toward the center.

When the short axis direction of the optical characteristic improvement structures 134 is cut by the cutting line I-I ', the optical characteristic improvement structures 134 have a continuous triangular cross section. The steps of the imaginary bases of the triangle shape are different from each other, and the heights are also different from each other. The vertex inner angles θ1, θ2, θ3, and θ4 of the triangular shape have 60 to 90 degrees. In particular, the vertex cabinets are preferably approximately 68 degrees.

When the long axis direction of the optical characteristic improving structures 134 is cut by the cutting line II-II ', the optical characteristic improving structures 134 have a parabolic shape (or a round shape). Although the curvatures of the unit parabolic shapes are the same in the drawings, the unit parabolic shapes may have different curvatures. The heights of the parabolic shapes are different.

FIG. 8A is a schematic diagram illustrating an optical characteristic corresponding to a short axis direction of an anti-prism film according to an embodiment of the present invention, and FIG. 8B corresponds to a long axis direction of an anti-prism film according to an embodiment of the present invention. It is a schematic diagram explaining an optical characteristic.

As shown in FIG. 8A, the light incident on the right slope of each prism mountains among the light incident from the bottom from the observer's point of view is shifted outward to the right, and the light incident on the left slope is approximately to the left. Shifted out As defined by Snell's law, the light incident on the slope is shifted to the right or left to exit.

Accordingly, one side slope and the other slope of the unit prism mountain function to diffuse a path of light incident from the bottom, and one slope of the unit prism mountain and the other slope of the unit prism mountain adjacent thereto are incident from the bottom. A function of focusing the light is performed.

Meanwhile, as shown in FIG. 8B, light incident on the left curved surface of the prism mountains among the light incident from the viewpoint of the observer is shifted to the left more approximately, and light incident on the right curved surface is approximately more right. It is shifted to and exits. As defined by Snell's law, the light incident on the curved surface is shifted out to the right or to the left.

Accordingly, one curved surface and the other curved surface of the prism mountains serve to diffuse a path of light incident from the bottom, and the curved surface of one side of the prism mountains and the other curved surface of the prism mountains adjacent thereto are light incident from the bottom. It focuses the light.

As described above, in the prism film according to the present invention, prismatic acids having different heights are formed corresponding to one axial direction, and the prism acids are discontinuous and have a round shape corresponding to the other axial direction. Because of this, even if foreign matters or defects can be prevented from sharply lowering the appearance quality.

In addition, in the anti-prism film according to the present invention, by rounding the pattern of the prism acid based on one axis (that is, the long axis), the degree of defects can be reduced compared to the prism having a mirror surface, and the light incident region is near. It can reduce the bright line generated in the

<Example-2 of reverse-prism film>

FIG. 9 is a perspective view of a reverse prism film according to another embodiment of the present invention, FIG. 10 is a plan view of a portion of the reverse prism film of FIG. 9 described above, and FIGS. 11A and 11B are views of FIG. These are sectional views cut | disconnected by cut line III-III 'and IV-IV', respectively.

9 to 11B, the anti-prism film 150 according to another embodiment of the present invention is discontinuous in one direction on a base (or base film) 152 and one surface of the base film 152. It includes a plurality of optical characteristic enhancement structure 154 formed as. Compared with the above-described embodiment of the present invention, the optical characteristic improving structures 154 are formed while exposing a portion of the base 152.

One surface of the base film 152 on which the optical characteristic improving structure 154 is formed faces the exit surface of the light guide plate 120, and the other surface of the base film 152 on which the optical characteristic improving structure 154 is not formed is formed. It is preferable to face toward the observer. Preferably, the base 152 and the optical characteristic improving structure 154 are made of the same material having the same refractive index.

The optical characteristic enhancement structures 154 are in contact with the base film 152 having a semi-wired shape. The optical characteristic improving structure has a major axis in the x-axis direction and a minor axis in the y-axis direction.

When the short axis direction of the optical characteristic improvement structures 154 is cut by the cutting line III-III ', the optical characteristic improvement structures 154 have discontinuous triangular cross sections. The steps of the bases of the triangle shape are the same, and the heights are different from each other. The vertex inner angles θ1, θ2, θ3, and θ4 of the triangular shape have 60 to 90 degrees. In particular, the vertex cabinets are preferably approximately 68 degrees.

When the long axis direction of the optical characteristic enhancement structures 154 is cut along the cutting line IV-IV ', the optical characteristic enhancement structures 154 have a parabolic shape (or a round shape). Although the curvatures of the unit parabolic shapes are the same in the drawings, the unit parabolic shapes may have different curvatures. The heights of the parabolic shapes are different.

12A is a schematic diagram illustrating an optical characteristic corresponding to a short axis direction of an anti-prism film according to another embodiment of the present invention, and FIG. 12B corresponds to a long axis direction of an anti-prism film according to another embodiment of the present invention. It is a schematic diagram explaining an optical characteristic.

As shown in FIG. 12A, one side slope and the other slope of the unit prism mountain serve to diffuse a path of light incident from the lower side, and one side slope of the unit prism mountain and the other side of the unit prism mountain adjacent thereto. The slopes perform a function of focusing light incident from the bottom, and a flat surface, which is a boundary between prism mountains, bypasses the straight light.

Meanwhile, as shown in FIG. 12B, one curved surface and the other curved surface of the prism mountains perform a function of diffusing the path of light incident from the lower side, and one curved surface of the prism mountains and the other curved surface of the prism mountains adjacent thereto. The focusing function is to focus light incident from the lower part, and a flat surface, which is a boundary between prism mountains, bypasses straight light.

<Example-3 of reverse-prism film>

FIG. 13A is a cross-sectional view of an anti-prism film according to another embodiment of the present invention, and FIG. 13B is a schematic diagram illustrating the optical characteristics of FIG. 13A.

As shown in FIGS. 13A and 13B, the uniaxial cut planes of the optical property improving structures included in the anti-prism film of another embodiment of the present invention define an entasis triangle shape. The above-mentioned full triangle shape condenses and diffuses the light provided from the outside. The steps of the hypothetical base sides of the full stomach are different from each other, and the heights are also different from each other. Although not shown, the long-axis cut surfaces of the optical property improving structures according to another embodiment of the present invention have a parabolic shape (or a round shape). The parabolic shape may have the same curvature or may have different curvatures.

<Example-4 of the reverse-prism film>

FIG. 14A is a cross-sectional view of an anti-prism film according to another embodiment of the present invention, and FIG. 14B is a schematic diagram illustrating the optical characteristics of FIG. 14B.

As shown in FIGS. 14A and 14B, the cut-out direction of the optical property improving structures included in the anti-prism film of another embodiment of the present invention has a first quadrangle of straight and a second quadrangle of curved. Defines a semi-entasis triangle shape. The light collecting function is performed by the first quadrangle (straight line) of the semi-filled triangular shape, and the diffusion function is performed by the second quadrangle (curve). Although not shown, the long-axis cut surfaces of the optical characteristic improving structures according to another embodiment of the present invention have a parabolic shape (or a round shape). The parabolic shape may have the same curvature or may have different curvatures.

<Example-5 of reverse-prism film>

15 is a cross-sectional view of an anti-prism film according to yet another embodiment of the present invention. In particular, the optical characteristic of the unit prism mountain whose curvature of one side is larger than the curvature of the other side is shown.

As shown in FIG. 15, the curved surface of the unit prism mountain having a large curvature from an observer's point of view refracts such that relatively many luminous fluxes are shifted to the left, and the surface of the unit prism mountain having a small curvature has a relatively small luminous flux toward the right. It performs a kind of diffusing function of refracting to be shifted and exiting. As such, the degree of diffusion can be adjusted by adjusting the curvature of the optical characteristic improving structure formed on the base. Although not shown, the curved surface on one side of the prism mountains and the curved surface on the other side of the prism mountains adjacent thereto serve to focus light incident from the bottom.

Next, examples of various liquid crystal display devices employing a backlight assembly having an anti-prism film according to the present invention will be described with reference to the accompanying drawings.

<Example 1 of Liquid Crystal Display Device>

16 is an exploded perspective view of a liquid crystal display according to an exemplary embodiment of the present invention.

Referring to FIG. 16, the liquid crystal display 200 according to the exemplary embodiment of the present invention includes a lamp 230, and light generated from the lamp 230 is reversed by the light guide plate 222 and the reflective sheet 221. Light incident on the prism film 223 and incident on the anti-prism film 223 is focused and diffused, and the liquid crystal panel 260 expresses an image by using the focused and diffused light. Reference numeral 262 denotes a color filter substrate, 264 denotes a TFT substrate, 270 denotes a source PCB, 266 denotes a source driver, and 268 denotes a gate driver.

The lamp 230 may use various light sources such as a cold cathode fluorescent lamp (CCFL), a light emitting diode (LED), and an external electrofluorescent lamp (EEFL).

Here, the light guide plate 222 has a prism pattern formed on one side thereof, and the prism formed on one side of the reflective sheet 221 and the light guide plate 222 transmits light generated from the lamp 230 to the light guide plate 222 surface. The light is converged in the vertical direction, and the emitted light is incident by the anti-prism film 223. The reverse-prism film 223 converges the light incident by the light guide plate 222 again and exits the liquid crystal panel 260.

The inverted-prism film 223 includes a plurality of prisms having a long axis and a short axis formed discontinuously in one direction on one surface of the base film, thereby converging light in various directions to effectively increase the front brightness. The prism shape of the prism film 223 is as described with reference to FIGS. 5 to 15.

Here, the prism of the prism film 223 is positioned to face the light guide plate 222, and the prism formation direction (or the long axis direction of the prism) of the prism film 223 and the prism pattern formation direction formed on the rear surface of the light guide plate 222. It is desirable to stagger each other.

<Example 2 of the Liquid Crystal Display Device>

17 is an exploded perspective view of a liquid crystal display according to another exemplary embodiment of the present invention.

Referring to FIG. 17, the liquid crystal display 300 according to another exemplary embodiment of the present invention passes through a light control unit 320 and a light control unit 320 for controlling light generated from the lamp 330. A polarizing plate (not shown) for polarizing light and a liquid crystal panel 360 for displaying an image using the light polarized through the polarizing plate. Reference numeral 362 denotes a color filter substrate, 364 denotes a TFT substrate, 370 denotes a source PCB, 366 denotes a source driver, and 368 denotes a gate driver.

The lamp 330 may use various light sources such as a cold cathode fluorescent lamp (CCFL), a light emitting diode (LED), and an external electrofluorescent lamp (EEFL).

The light control unit 320 is a set of films or plates that play a series of roles until the light generated from the lamp 330 is adjusted to supply the adjusted light to the liquid crystal panel 360.

Light generated from the lamp 330 positioned on the side of the light guide plate 322 is emitted to the diffusion film 323 through the light guide plate 322 and the reflective sheet 321 below the light guide plate 322, and the diffusion film 323 is incident light. Is diffused to the anti-prism film 324, and the anti-prism film 324 converges the light incident from the diffuser film 323 in the front direction and exits the liquid crystal panel 360.

The anti-prism film 324 includes a plurality of prisms having a long axis and a short axis discontinuously formed in one direction on one surface of the base film, thereby converging light in various directions to effectively increase the front brightness. The prism shape of the anti-prism film 324 is as described with reference to FIGS. 5 to 15.

Here, the prism of the reverse-prism film 324 is positioned toward the light guide plate 322, and the prism formed in the prism forming direction (or the long axis direction of the prism) of the reverse-prism film 324 and the back surface of the light guide plate 322. It is preferable to make pattern formation directions mutually staggered.

<Example 3 of Liquid Crystal Display Device>

18 is an exploded perspective view of a liquid crystal display according to another exemplary embodiment of the present invention.

Referring to FIG. 18, the liquid crystal display device 400 according to another exemplary embodiment of the present invention passes through a light control unit 420 and a light control unit 420 for adjusting light generated from the lamp 430. A polarizer (not shown) for polarizing a light and a liquid crystal panel 460 for displaying an image using light polarized through the polarizer. Reference numeral 462 denotes a color filter substrate, 464 denotes a TFT substrate, 470 denotes a source PCB, 466 denotes a source driver, and 468 denotes a gate driver.

The lamp 430 may use various light sources such as a cold cathode fluorescent lamp (CCFL), a light emitting diode (LED), and an external electrofluorescent lamp (EEFL).

The light control unit 420 is a set of films or plates that play a series of roles until the light generated from the lamp 430 is adjusted to supply the adjusted light to the liquid crystal panel 460.

Light generated from the plurality of lamps 430 disposed in parallel to the rear surface of the liquid crystal panel 462 is incident directly onto the diffusion film 423 or through the reflection sheet 421 to the diffusion film 423. The diffuser film 423 diffuses the incident light and exits the anti-prism film 424, and the anti-prism film 424 converges the light incident from the diffuser film 423 in the front direction.

The anti-prism film 424 includes a plurality of prisms having a long axis and a short axis discontinuously formed in one direction on one surface of the base film, thereby converging light in various directions to effectively increase the front brightness. The prism shape of the anti-prism film 424 is as described above with reference to FIGS. 5 to 15.

Here, the prism of the anti-prism film 424 is positioned to face the diffusion film 423, and the prism forming direction (or the long axis direction of the prism) of the anti-prism film 424 and the extension of the lamp 430 The directions are preferably parallel to each other.

In addition, the upper region of the lamp 430 has a greater intensity of incident light than the upper region between the lamps 430. Thus, the inclination angle of the prism formed in the anti-prism film 424 may have a constant relationship with the lamp for uniformity of overall brightness. That is, prisms having an average larger angle of inclination are formed in an area corresponding to the upper region of the lamp 430, and prisms having an average smaller angle of inclination in an area corresponding to the upper region between the lamps 430. Can form them.

As described above, the anti-prism film according to the present invention comprises a first surface to which light is incident and a second surface to emit light incident through the first surface, and the second surface faces one direction. Many prisms are discontinuously formed. Therefore, the light of various directions can be converged and diffused, so that the front brightness is improved. As a result, it is possible to meet the high brightness, light weight, and cost reduction which are required in recent liquid crystal display devices.

Although described above with reference to the embodiments, those skilled in the art can be variously modified and changed within the scope of the invention without departing from the spirit and scope of the invention described in the claims below. I can understand.

1 is a perspective view of a backlight assembly having a general prism film.

2 is a perspective view of a backlight assembly according to an embodiment of the present invention.

FIG. 3 is a diagram schematically illustrating the light guide method using the light guide plate of FIG. 2.

4 is a view for explaining the light guide plate of FIG.

5 is a perspective view of an anti-prism film according to an embodiment of the present invention.

FIG. 6 is a plan view of a portion of the anti-prism film of FIG. 5 described above. FIG.

7A and 7B are cross-sectional views taken along cut lines II ′ and II-II ′ of FIG. 6, respectively.

8A and 8B are schematic diagrams illustrating optical characteristics of an anti-prism film according to an embodiment of the present invention.

9 is a perspective view of an anti-prism film according to another embodiment of the present invention.

FIG. 10 is a plan view of a portion of the anti-prism film of FIG. 9 described above. FIG.

11A and 11B are cross-sectional views taken along cut lines III-III 'and IV-IV' of FIG. 6, respectively.

12A and 12B are schematic diagrams illustrating optical characteristics of an anti-prism film according to another embodiment of the present invention.

FIG. 13A is a cross-sectional view of an anti-prism film according to another embodiment of the present invention, and FIG. 13B is a schematic diagram illustrating the optical characteristics of FIG. 13A.

FIG. 14A is a cross-sectional view of an anti-prism film according to another embodiment of the present invention, and FIG. 14B is a schematic diagram illustrating the optical characteristics of FIG. 14B.

15 is a cross-sectional view of an anti-prism film according to yet another embodiment of the present invention.

16 is an exploded perspective view of a liquid crystal display according to an exemplary embodiment of the present invention.

17 is an exploded perspective view of a liquid crystal display according to another exemplary embodiment of the present invention.

18 is an exploded perspective view of a liquid crystal display according to another exemplary embodiment of the present invention.

<Description of the symbols for the main parts of the drawings>

110: light generating unit 120: light guide plate

130, 150 reverse-prism film 140: reflective sheet

132, 152: base film 134, 154: optical characteristic improvement structure

Claims (36)

Base; And A cross section protruded in one direction on one surface of the base and cut in a direction parallel to the surface of the base has a semi-wire shape, and a cross section cut perpendicular to the surface of the base in the long axis direction of the semi-wire shape. The optical film which has this round shape and includes many optical characteristic improvement structures which condense and diffuse | emit light provided from the exterior. The optical film of claim 1, wherein the optical characteristic improving structure is formed discontinuously. The optical film of claim 1, wherein the optical characteristic improving structure is formed continuously. The optical film of claim 1, wherein the optical characteristic improving structure condenses and diffuses light provided from the outside and emits the light through the other surface of the base. The cross section of the optical characteristic improving structure is triangular in shape, and the light is collected from the outside by the triangular shape when cutting the short axis of the semi-wired shape in the normal direction of the bottom surface. An optical film, characterized in that. The optical film of claim 5, wherein the heights of the triangles are different from each other. The optical film according to claim 5, wherein the vertex inside of the triangle is any one of 60 to 90 degrees. The optical film of claim 5, wherein the vertex interior of the triangular shape is 68 degrees. The optical film of claim 1, wherein the optical characteristic improving structure is formed on a base having a predetermined thickness with different heights. The optical film according to claim 1, wherein the round shape corresponding to one optical characteristic enhancement structure has the same curvature. The optical film of claim 1, wherein the round shapes corresponding to one optical characteristic enhancement structure have different curvatures. The optical film of claim 1, wherein the round shapes corresponding to the plurality of optical characteristic enhancement structures have different curvatures. The optical film of claim 1, wherein the optical characteristic improving structure has two slopes facing each other, and each of the two slopes is a curved surface. The cross section of the optical characteristic improving structure is an entasis triangular shape, and when the short axis of the semi-wired shape is cut in the normal direction of the bottom surface, An optical film, characterized in that to focus and diffuse the light provided from. The optical film according to claim 1, wherein the optical characteristic improving structure has two slopes facing each other, one of the slopes being a plane, and the other being a curved surface. A base having a predetermined thickness on the X-Y plane; And One side of the base protrudes with different heights toward the X axis, and a cross section obtained by cutting the XZ plane into a cutting plane defines a round shape with a predetermined curvature to diffuse light from the outside, and a YZ plane is cut into the cutting plane. One cross section defines a triangular shape and includes a plurality of optical characteristic enhancement structures that condense and emit light provided from the outside. A base formed on the X-Y plane; And One side of the base protrudes with different heights toward the X axis, and a cross section obtained by cutting the XZ plane into a cutting plane defines a round shape with a predetermined curvature to diffuse light from the outside, and a YZ plane is cut into the cutting plane. An optical film comprising a plurality of optical properties improving structure that one cross section defines a full triangle shape, and condenses and diffuses the light provided from the outside. A lamp for emitting light; And A backlight assembly comprising an optical film that is emitted to the other side by improving the characteristics of the light provided from one side through a plurality of optical characteristic enhancement structure formed to protrude in one direction. 19. The backlight assembly of claim 18, wherein the optical characteristic improving structure is formed toward the one side. The backlight assembly of claim 18, further comprising a light guide plate that guides and emits a path of light emitted from the lamp. The method of claim 20, wherein the optical film is disposed on the light guide plate, And the optical characteristic enhancing structure is formed toward an upper surface of the light guide plate. 19. The backlight assembly of claim 18, wherein the one direction is the same as the direction in which the lamp extends. 19. The method of claim 18, wherein the optical film comprises a base, The optical characteristic improvement structure is a cross-section cut into the bottom surface parallel to the surface of the base defines a semi-wire shape, the cross-section cut in the normal direction of the base with a cutting line of the long axis of the semi-wire shape is round And define a shape and diffuse the first emitted light by the round shape. 19. The method of claim 18, wherein the optical film comprises a base, The optical characteristic improvement structure is a cross-section cut into the bottom surface parallel to the surface of the base defines a semi-lined shape, the cross-section cut in the normal direction of the base by cutting the short axis of the semi-wired shape is a triangle And defining a shape and condensing the first emitted light by the triangular shape. 19. The method of claim 18, wherein the optical film comprises a base, The optical characteristic enhancement structure has a cross section cut into a bottom surface parallel to the surface of the base to define a semi-wire shape, and a cross section cut in the normal direction of the base with a short line of the semi-wire shape as a cutting line. Defining a soaking triangle shape and condensing and diffusing the first emitted light by the filling triangle shape. 19. The method of claim 18, wherein the optical film comprises a base, The optical characteristic improvement structure is a cross-section cut into the bottom surface parallel to the surface of the base defines a semi-wire shape, the cross-section cut in the normal direction of the base by cutting the short axis of the semi-wire shape is a first Defining a semi-entasis triangular shape in which one quadrilateral is a straight line and a second quadrangle is curved, and condensing and diffusing the first emitted light by the semi-belly triangular shape Backlight assembly. The backlight assembly of claim 18, wherein a prism acid in a direction perpendicular to a direction in which the lamp extends is formed on a rear surface of the light guide plate, and a vertex angle of the prism acid is 100 to 120 degrees. 29. The backlight assembly of claim 27, wherein the vertex angle of the optical characteristic improving structure of the optical film has 60 to 90 degrees. A light source for generating light; A liquid crystal panel displaying an image using a potential difference applied to the liquid crystal layer; And And an optical film formed with a plurality of optical characteristic enhancement structures protruding toward one direction, the optical control unit for adjusting the characteristics of the light generated from the light source to provide the liquid crystal panel. The method of claim 29, wherein the optical film is disposed under the liquid crystal panel, And the optical characteristic improving structure is formed toward the opposite direction of the liquid crystal panel. 30. The method of claim 29, wherein the optical film comprises a base, The optical characteristic improvement structure is a cross-section cut into the bottom surface parallel to the surface of the base defines a semi-wire shape, the cross-section cut in the normal direction of the base with a cutting line of the long axis of the semi-wire shape is round And defining a shape and diffusing the first emitted light to the liquid crystal panel by the round shape. 30. The method of claim 29, wherein the optical film comprises a base, The optical characteristic improvement structure is a cross-section cut into the bottom surface parallel to the surface of the base defines a semi-lined shape, the cross-section cut in the normal direction of the base by cutting the short axis of the semi-wired shape is a triangle And defining a shape and condensing the first emitted light by the triangular shape to provide the light to the liquid crystal panel. 30. The method of claim 29, wherein the optical film comprises a base, The optical characteristic enhancement structure has a cross section cut into a bottom surface parallel to the surface of the base to define a semi-wire shape, and a cross section cut in the normal direction of the base with a short line of the semi-wire shape as a cutting line. Defining a so called triangular shape, and condensing and diffusing the first emitted light by the soaked triangular shape to provide it to the liquid crystal panel. 30. The method of claim 29, wherein the optical film comprises a base, The optical characteristic improvement structure is a cross-section cut into the bottom surface parallel to the surface of the base defines a semi-wire shape, the cross-section cut in the normal direction of the base by cutting the short axis of the semi-wire shape is a first The liquid crystal panel is defined by defining a semi-entasis triangular shape in which one quadrangle is a straight line and a second quadrangle is curved, and condensing and diffusing the first emitted light by the semi-filled triangular shape. The liquid crystal display device provided in the. The method of claim 29, wherein the light control unit further comprises a light guide plate for guiding and exiting the path of the light generated from the light source, And the optical film is disposed on an exit surface of the light guide plate. 30. The liquid crystal display device according to claim 29, wherein the light source includes a plurality of light sources, and the plurality of light sources are disposed parallel to the rear surface of the liquid crystal panel.