KR102428436B1 - Light guide plate, back light unit having the same, and liquid crystal display device - Google Patents

Abstract

The present invention comprises a base layer and a coating layer formed on one surface of the base layer and including a plurality of optical patterns, and a first curved surface and a second curved surface in the form of a wave curve on each of the side and upper surfaces of the optical pattern and a light guide plate formed thereon. According to the disclosed invention, it is possible to avoid the moire phenomenon due to the pattern interference between the optical pattern of the light guide plate and the pixel of the panel, and the lenticular function can be maintained as it is.

Description

A light guide plate, a backlight unit having the same, and a liquid crystal display using the same

The present invention relates to a light guide plate, a backlight unit having the same, and a liquid crystal display including the same.

A liquid crystal display (LCD) is a device that displays an image by injecting liquid crystal between two glass plates and applying power to the upper and lower glass plate electrodes to change the arrangement of liquid crystal molecules in each pixel.

Unlike a cathode ray tube display (CRT), a plasma display panel (PDP), etc., the display by the liquid crystal display itself is non-luminous, so it cannot be used in a place without light.

A backlight unit irradiated uniformly on the information display surface is mounted for the purpose of compensating for this disadvantage and enabling use in a dark place.

As a low-power, high-brightness liquid crystal display is required, the backlight unit includes an optical sheet such as a prism sheet. The prism sheet has a plurality of prism patterns to condense the light emitted from the side to the front, thereby contributing to an overall increase in luminance.

However, the repeatedly formed prism pattern may cause a moiré phenomenon to deteriorate display quality.

In particular, in the light guide plate (LGP) applied to the edge-type LED model, the lenticular reduces the scanning, light collection, hot spot reduction, and defect rate (that is, the visibility of pattern and scratch defects). drop it).

However, the lenticular of the light guide plate has the above advantages and needs to be applied. However, if the shielding property is deteriorated due to a reduction in the number of sheets or a reduction in haze, it is a cause of the occurrence of moire due to the overlapping phenomenon between the panel pixels. . In addition, although the lenticular of the light guide plate has several advantages, it causes a moire phenomenon and becomes an obstacle in realizing high luminance by reducing the number of sheets or reducing haze.

On the other hand, when the lenticular is deleted, the above-mentioned advantages disappear and the dot pattern visibility of the light guide plate is increased.

An object of the present invention is to provide a light guide plate capable of reducing the number of sheets and realizing high brightness by preventing moire caused by overlapping lines between the optical pattern of the light guide plate and the pixels of the panel.

In addition, the problem to be solved by the present invention is a backlight unit capable of reducing the number of sheets and realizing high brightness by preventing moire caused by overlapping lines between the optical pattern of the light guide plate and the pixels of the panel, and a liquid crystal display including the same that you want to provide.

The problems of the present invention are not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

The light guide plate according to the present invention for solving the above problems is configured to include a base layer, a coating layer formed on the upper surface of the base layer, and a plurality of optical patterns formed on the coating layer and formed along the longitudinal direction, and the side surface of the optical pattern and a first curved surface and a second curved surface in the form of a wave curve on the upper surface.

The first curved surface on the side of the optical pattern may have a structure in which the first convex portion and the first concave portion are repeated in left and right longitudinal directions.

The second curved surface on the upper surface of the optical pattern may have a structure in which second convex portions and second concave portions are repeated in vertical directions.

The width of the first convex portion of the first curved surface of the optical pattern is 5 to 10% of the optical pattern pitch (P).

The optical pattern may be a lenticular pattern.

A backlight unit having a light guide plate of the present invention for solving the above problems includes a light guide plate, a light source disposed on one surface of the light guide plate, and an optical sheet disposed on an upper surface of the light guide plate, wherein the light guide plate includes a base layer; The light guide plate may include a coating layer formed on one surface of the base layer and including a plurality of optical patterns, and having first curved surfaces and second curved surfaces in the form of wave curves on side surfaces and upper surfaces of the optical patterns, respectively.

In addition, the first curved surface on the side of the optical pattern may have a structure in which the first convex portion and the first concave portion are repeated in left and right longitudinal directions.

In addition, the second curved surface on the upper surface of the optical pattern may have a structure in which the second convex portion and the second concave portion are repeated in the upper and lower vertical directions.

The width of the first convex portion of the first curved surface of the optical pattern may be 5 to 10% of the optical pattern pitch (P).

The width of the first convex portion of the first curved surface of the optical pattern may be 2 to 4 μm.

In addition, a liquid crystal display device according to another embodiment of the present invention for solving the another problem includes a backlight unit having the light guide plate as described above.

Specific details of other embodiments are included in the detailed description and drawings.

The light guide plate according to the present invention, a backlight unit having the same, and a liquid crystal display including the same can avoid a moire phenomenon due to pattern interference between the optical pattern of the light guide plate and the pixels of the panel, and maintain the lenticular function.

In addition, the light guide plate according to the present invention, the backlight unit having the same, and the liquid crystal display device can use a product having a low sheet haze, so that the luminance can be increased.

In addition, the number of sheets can be reduced in the light guide plate according to the present invention, the backlight unit having the same, and the liquid crystal display including the same.

In addition, the light guide plate according to the present invention, a backlight unit having the same, and a liquid crystal display including the same can remove a sheet when a panel in which a sheet is integrated on a polarizing plate is applied.

1 is a diagram schematically illustrating a light guide plate according to an embodiment of the present invention.
2 is a plan view schematically showing the left and right shapes of the optical pattern of the light guide plate according to the present invention.
3 is a plan view illustrating the width, pitch, and wavelength of the optical pattern of the light guide plate according to the present invention.
4 is a side view schematically illustrating upper and lower shapes of an optical pattern of a light guide plate according to the present invention.
5 is a diagram schematically illustrating an embodiment of a liquid crystal display to which a light guide plate provided with an optical pattern according to the present invention is applied.
6 is a view schematically showing another embodiment of a liquid crystal display to which a light guide plate provided with an optical pattern according to the present invention is applied.

Advantages and features of the present invention, and a method of achieving them will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in a variety of different forms, and only these embodiments allow the disclosure of the present invention to be complete, and common knowledge in the art to which the present invention pertains It is provided to fully inform the possessor of the scope of the invention, and the present invention is only defined by the scope of the claims.

Reference to an element or layer “on” another element or layer includes any intervening layer or other element directly on or in the middle of another element. On the other hand, when an element is referred to as "directly on", it is indicated that there are no intervening elements or layers. Like reference numerals refer to like elements throughout. “And/or” includes each and every combination of one or more of the recited items.

Although the first, second, etc. are used to describe various elements, these elements are not limited by these terms, of course. These terms are only used to distinguish one component from another. Therefore, it goes without saying that the first component mentioned below may be the second component within the spirit of the present invention.

The terminology used herein is for the purpose of describing the embodiments and is not intended to limit the present invention. In this specification, the singular also includes the plural, unless specifically stated otherwise in the phrase. As used herein, “comprises” and/or “comprising” does not exclude the presence or addition of one or more other components in addition to the stated components.

Unless otherwise defined, all terms (including technical or scientific terms) used herein may be used with the meaning commonly understood by those of ordinary skill in the art to which the present invention belongs. In addition, terms defined in a commonly used dictionary are not to be interpreted ideally or excessively unless specifically defined explicitly.

Spatially relative terms "below", "lower", "above", "upper", etc., as shown in the drawings, refer to one component and another component. It can be used to easily describe the correlation. A spatially relative term should be understood as a term that includes different directions of components during use or operation in addition to the directions shown in the drawings. For example, when a component shown in the drawing is turned over, a component described as "beneath" or "beneath" of another component may be placed "above" of the other component. Therefore, the exemplary term “below” may include both directions below and above. Components may also be oriented in other directions, and thus spatially relative terms may be interpreted according to the orientation. .

As used herein, the term "~ sheet" may be used in the meaning of "~ film" and "~ plate".

Hereinafter, a light guide plate according to the present invention will be described with reference to FIGS. 1 to 4 .

1 is a view schematically showing a light guide plate according to the present invention.

2 is a plan view schematically illustrating the left and right shapes of the optical pattern of the light guide plate according to the present invention.

Referring to FIG. 1 , a light guide plate 100 according to an embodiment of the present invention is formed on a base layer 110 and an upper surface of the base layer 110 , and a coating layer 120 including at least one optical pattern 124 . ) may be included.

The base layer 110 may support the coating layer 120 and guide light incident from the light source to be emitted to a freeze sheet (not shown) on which a prism pattern (not shown) is formed.

The base layer 110 may have a thickness of 200 μm to 700 μm, specifically 300 μm to 500 μm, and may be used in an optical display device within the above range.

The refractive index of the base layer 110 may be 1.50 or more, specifically 1.50 to 1.60, and the light efficiency may be increased by increasing the light output rate in the above range. The base layer 110 may be formed of a resin having a refractive index of 1.50 or more, specifically 1.50 to 1.60, for example, polycarbonate, polymethyl (meth) acrylate, or the like. In particular, the polycarbonate resin may be advantageous in reducing the thickness of the base layer.

In addition, the coating layer 120 may be formed on one surface of the base layer 110 , increase luminance by preventing light from being scattered, and may emit light incident from the base layer 110 . The coating layer 120 may have a thickness of 10 μm to 40 μm, and may be used in an optical display device within the above range.

In addition, the coating layer 120 may have a refractive index of 1.50 to 1.65, and may increase the light output rate in the above range to increase light efficiency. The coating layer 120 may be formed of a resin for a coating layer having a refractive index of 1.50 to 1.65. The resin for the coating layer includes an ultraviolet curable resin, and specifically, may be formed of a (meth)acrylic resin, a polycarbonate-based resin, a styrene-based resin, an olefin-based resin, a polyester-based resin, or a combination thereof.

The coating layer 120 may include at least one or more optical patterns 124 .

The optical pattern 124 is provided with a first curved surface formed alternately with first convex portions 124a and first concave portions 124b waving in the left and right directions, that is, in the longitudinal direction, on both sides, and an upper portion of the optical pattern 124 is formed. A second curved surface may be formed in which second convex portions 124c and second concave portions 124d that are waved in the upper and lower directions are alternately formed thereon.

1 illustrates a light guide plate having a lenticular pattern formed as the optical pattern 124 , the optical pattern 124 is not limited as long as curved surfaces are formed on the side surface and the upper surface. For example, the optical pattern may include a prism pattern, a microlens pattern, an emboss pattern, or a combination thereof in which curved surfaces are formed on the side surface and the upper surface.

The optical pattern 124 may have an aspect ratio of 0.10 to 0.50 and a radius of curvature R of the curved surface of 10 μm to 35 μm. It serves to guide and diffuse the light incident within the above range, and to narrow the viewing angle in the vertical direction to the optical pattern 124 , thereby increasing visibility and luminance.

The width P1 of the optical pattern 124 may be 10 μm to 50 μm, and the height H may be 10 μm to 35 μm. In the above range, it is possible to increase light efficiency by condensing light in the left and right directions, and serves to guide and diffuse the incident light, and to narrow the viewing angle in the vertical direction of the optical pattern 124 to increase visibility and luminance. can do it

Referring to FIG. 2 , the cross-section of the optical pattern 124 may be semicircular. However, if the aspect ratio is 0.10 to 0.50 and the radius of curvature R of the curved surface is 10 μm to 35 μm, the cross section of the optical pattern may be a deformed shape, a semi-elliptical shape or a semi-elliptical shape modified shape.

The optical pattern 124 may have a refractive index different from that of the coating layer 120 , but fairness can be improved by making the coating layer and the optical pattern have the same refractive index.

3 is a plan view illustrating the width, pitch, and wavelength of the optical pattern of the light guide plate according to the present invention.

Referring to FIG. 3 , the first curved surface on the side of the optical pattern 124 may have a structure in which the first convex part 124a and the first concave part 124b are repeated in the left and right longitudinal directions. have. In this case, the first convex portion 124a and the first concave portion 124b formed on the first curved surface on the left side are the first convex portion 124a and the first concave portion 124b formed on the first curved surface on the right side. ) and correspond respectively to

In addition, the width W of the first convex portion 124a of the first curved surface of the optical pattern 124 may be 5 to 10% of the pitch P of the optical pattern 124 .

4 is a side view schematically illustrating upper and lower shapes of an optical pattern of a light guide plate according to the present invention.

Referring to FIG. 4 , the second curved surface on the upper surface of the optical pattern 124 may have a structure in which second convex portions 124c and second concave portions 124d are repeated in up and down vertical directions. have.

In addition, the optical pattern 124 may be a lenticular pattern.

As described above, in the light guide plate according to the present invention, it is possible to avoid the moire phenomenon due to the pattern interference between the optical pattern of the light guide plate and the pixel of the panel, and the lenticular function can be maintained as it is.

In addition, the light guide plate according to the present invention can use a product having a low sheet haze, so that the luminance can be increased.

Hereinafter, an embodiment of a liquid crystal display to which a backlight unit provided with a light guide plate according to an embodiment of the present invention is applied will be described with reference to 5 .

5 is a diagram schematically illustrating an embodiment of a liquid crystal display to which a backlight unit provided with a light guide plate according to the present invention is applied.

Referring to FIG. 5 , a liquid crystal display 200 according to an embodiment of the present invention includes a liquid crystal panel 250 for a liquid crystal display, and polarizing plates 256 and 258 respectively formed on the lower and upper surfaces of the liquid crystal panel 250 . ), and a backlight unit 270 provided under the liquid crystal panel 250 .

The liquid crystal panel 250 includes a thin film transistor substrate 252 , a color filter substrate 254 , and a liquid crystal cell layer (not shown) enclosed between the substrates. In addition, the liquid crystal cell layer may be a vertical alignment (VA) mode, an in plane switching (IPS) mode, a fringe field switching (FFS) mode, or a twisted nematic (TN) mode.

In addition, the polarizing plates 256 and 258 may include a polarizer, a protective film and/or a retardation film formed on the polarizer.

On the other hand, the backlight unit is disposed on the light source 240, the light guide plate 210 for guiding the light incident from the light source 240, the reflective sheet 260 disposed under the light guide plate 210, and the light guide plate 210, and An optical sheet 230 including a plurality of prism sheets 232 and 234 may be included, and the light guide plate 210 may include a light guide plate according to an embodiment of the present invention.

The light source 240 generates light and is disposed on one side of the light guide plate. As the light source 240 , a linear light source lamp or a surface light source lamp, a Light Emitting Diode (LED), a Cold Cathode Fluorescent Lamp (CCFL), a Hot Cathode Fluorescent Lamp (HCFL), an External Electrode Fluorescent Lamp (EEFL), or the like may be used. A light source cover (not shown) may be further provided outside the light source for the purpose of protecting the light source.

In addition, the case where the LED 242 is employed as the light source 240 is described as an example, and an LED substrate 244 is disposed on the rear surface of the LED 242 .

In addition, the position of the light source 240 in the backlight unit is not limited, and may be an edge type backlight unit disposed on a side surface of the light guide plate 210 .

The light guide plate 210 may serve to guide the light incident from the light source to the optical sheet 230 including a plurality of prism sheets 232 and 234 .

In particular, the light guide plate 210 moves the light emitted from the light source through total internal reflection and emits it upward through a scattering pattern formed on the lower surface of the light guide plate. Although the drawing illustrates the case where the upper and lower surfaces of the light guide plate are parallel, a wedge-shaped light guide plate having a thickness of one side greater than the thickness of the other side may be applied.

Although not shown in the drawings, the first curved surface on the side of the optical pattern 224 has a structure in which the first convex part (not shown) and the first concave part (not shown) are repeated in the left and right longitudinal directions. can be done At this time, each of the first convex portion (not shown) and the first concave portion (not shown) formed on the first curved surface on the left side is a first concave portion (not shown) and first formed on the first curved surface on the right side, respectively. Each corresponds to a convex portion (not shown).

In addition, the width W of the first convex portion (not shown) of the first curved surface of the optical pattern 224 may be 5 to 10% of the pitch P of the optical pattern 224 .

In addition, referring to FIG. 5 , the second curved surface on the upper surface of the optical pattern 224 has a structure in which second convex portions 224c and second concave portions 224d are repeated in up and down vertical directions. can be done

In addition, the optical pattern 224 may be a lenticular pattern.

Meanwhile, a reflective sheet 260 is disposed under the light guide plate 210 to reflect the light emitted downward from the light guide plate upward. In particular, the reflective sheet 260 may serve to increase light efficiency by reflecting the light generated from the light source to be incident back to the light guide plate.

The plurality of prism sheets 232 and 234 may include a base film and a prism pattern formed on a lower surface of the base film.

In addition, a light diffusion layer may be further formed on one surface of the prism sheet 234 , and the light diffusion layer may be formed of one or more of a pattern such as irregularities and a coating layer including diffusion particles.

In addition, one or more protective sheets, diffusion sheets, etc. may be further formed on the prism sheet 234 .

In addition, a polarizing plate 256 may be positioned directly on the prism sheet 230 .

As described above, in the liquid crystal display device to which the backlight unit provided with the light guide plate according to the present invention is applied, it is possible to avoid the moire phenomenon due to the pattern interference between the optical pattern of the light guide plate and the panel pixels, and the lenticular function can be maintained as it is.

Further, in the liquid crystal display to which the backlight unit provided with the light guide plate according to the present invention is applied, it is possible to use a product having a low sheet haze, so that the luminance can be increased.

Hereinafter, another embodiment of a liquid crystal display to which a backlight unit provided with a light guide plate according to the present invention is applied will be described with reference to 6 .

6 is a diagram schematically illustrating another embodiment of a liquid crystal display to which a backlight unit provided with a light guide plate according to the present invention is applied.

Referring to FIG. 6 , a liquid crystal display 300 according to another embodiment of the present invention includes a liquid crystal panel 350 for a liquid crystal display, and polarizing plates 356 and 358 respectively formed on the lower and upper surfaces of the liquid crystal panel 350 . ), and a backlight unit 370 provided under the liquid crystal panel 350 .

The liquid crystal panel 350 includes a thin film transistor substrate 352 , a color filter substrate 354 , and a liquid crystal cell layer (not shown) enclosed between the substrates. In addition, the liquid crystal cell layer may be a vertical alignment (VA) mode, an in plane switching (IPS) mode, a fringe field switching (FFS) mode, or a twisted nematic (TN) mode.

In addition, the polarizing plates 356 and 358 may include a polarizer, a protective film and/or a retardation film formed on the polarizer.

In addition, the optical sheet 330 may be directly attached to the rear surface of the polarizing plate 356 .

The optical sheet 330 may include a plurality of prism sheets, and the prism sheets may include a base film and a prism pattern formed on a lower surface of the base film.

In addition, although not shown in the drawings, a light diffusion layer may be further formed on one surface of the prism sheet, and the light diffusion layer may be formed of one or more of a pattern such as irregularities and a coating layer including diffusion particles.

Meanwhile, the backlight unit 370 may include a light source 340 , a light guide plate 310 guiding light incident from the light source 340 , and a reflective sheet 360 disposed under the light guide plate 310 .

The light source 340 generates light and is disposed on one side of the light guide plate. As the light source 340, a linear light source lamp or a surface light source lamp, a Light Emitting Diode (LED), a Cold Cathode Fluorescent Lamp (CCFL), a Hot Cathode Fluorescent Lamp (HCFL), an External Electrode Fluorescent Lamp (EEFL), or the like may be used. A light source cover (not shown) may be further provided outside the light source for the purpose of protecting the light source.

In addition, the case where the LED 342 is employed as the light source 340 is described as an example, and an LED substrate 344 is disposed on the rear surface of the LED 342 .

In addition, the position of the light source 340 in the backlight unit is not limited, and may be an edge type backlight unit disposed on a side surface of the light guide plate 310 .

The light guide plate 310 may serve to guide the light incident from the light source to the optical sheet 330 adhered to the rear surface of the polarizing plate 356 .

In particular, the light guide plate 310 moves the light emitted from the light source through total internal reflection and emits it upward through a scattering pattern formed on the lower surface of the light guide plate. Although the drawing illustrates the case where the upper and lower surfaces of the light guide plate are parallel, a wedge-shaped light guide plate having a thickness of one side greater than the thickness of the other side may be applied.

Although not shown in the drawings, the first curved surface on the side of the optical pattern 324 has a structure in which the first convex part (not shown) and the first concave part (not shown) are repeated in the left and right longitudinal directions. can be done At this time, each of the first convex portion (not shown) and the first concave portion (not shown) formed on the first curved surface on the left side is a first concave portion (not shown) and first formed on the first curved surface on the right side, respectively. Each corresponds to a convex portion (not shown).

In addition, the width W of the first convex portion (not shown) of the first curved surface of the optical pattern 324 may be 5 to 10% of the pitch P of the optical pattern 324 .

In addition, referring to FIG. 6 , the second curved surface on the upper surface of the optical pattern 324 has a structure in which second convex portions 324c and second concave portions 324d are repeated in up and down vertical directions. can be done

In addition, the optical pattern 324 may be a lenticular pattern.

Meanwhile, a reflective sheet 360 is disposed under the light guide plate 310 to reflect the light emitted downward from the light guide plate upward. In particular, the reflective sheet 360 may serve to increase light efficiency by reflecting the light generated from the light source to be incident back to the light guide plate.

Hereinafter, the present invention will be described with reference to specific examples, but the present invention is not limited to these examples and variously changed and implemented by those skilled in the art to which the present invention pertains within the scope of the technical idea. Of course it could be.

Example 1

The wave width (W) of the optical pattern provided in the coating layer of the light guide plate according to the present invention, that is, the lenticular pattern is zero (0 μm), the pitch (P) of the optical pattern is 50 μm, and the height (H) of the optical pattern is 7 to 8 μm, and as a sheet structure, the upper and lower prism sheets constituting the optical sheet are disposed on the upper part of the light guide plate, and the diffuser is laminated to the lower polarizing plate attached to the rear surface of the liquid crystal panel separately from the upper and lower prism sheets. This is an example of a case where

Here, although the case in which the pitch P of the optical pattern is 50 μm has been described as an example, the present invention is not limited thereto, and in some cases, a case of 200 μm or 300 μm may be described as an example.

Example 2

The optical pattern provided in the coating layer of the light guide plate according to the present invention, that is, the wave width (W) of the lenticular pattern is 1 to 2 μm, the pitch (P) of the optical pattern is 50 μm, and the height (H) of the optical pattern is 7 to 8 μm In the sheet structure, the upper and lower prism sheets constituting the optical sheet are disposed on the upper part of the light guide plate, and the diffuser is laminated to the lower polarizing plate attached to the rear surface of the liquid crystal panel separately from the upper and lower prism sheets. This is an example of a case.

Here, although the case where the pitch P of the optical pattern is 50 μm has been described as an example, the present invention is not limited thereto, and in some cases, a case of 200 μm or 300 μm may be described as an example.

Example 3

The optical pattern provided in the coating layer of the light guide plate according to the present invention, that is, the wave width (W) of the lenticular pattern is 2-3 μm, the pitch (P) of the optical pattern is 50 μm, and the height (H) of the optical pattern is 7-8 μm In the sheet structure, the upper and lower prism sheets constituting the optical sheet are disposed on the upper part of the light guide plate, and the diffuser is laminated to the lower polarizing plate attached to the rear surface of the liquid crystal panel separately from the upper and lower prism sheets. This is an example of the case.

Here, although the case in which the pitch P of the optical pattern is 50 μm has been described as an example, the present invention is not limited thereto, and in some cases, a case of 200 μm or 300 μm may be described as an example.

Example 4

The optical pattern provided in the coating layer of the light guide plate according to the present invention, that is, the wave width (W) of the lenticular pattern is 5 μm, the pitch (P) of the optical pattern is 50 μm, the height (H) of the optical pattern is 7 to 8 μm, In the sheet structure, the upper and lower prism sheets constituting the optical sheet are disposed on the upper part of the light guide plate, and the diffuser is laminated to the lower polarizing plate attached to the rear surface of the liquid crystal panel separately from the upper and lower prism sheets. This is an example.

Here, although the case in which the pitch P of the optical pattern is 50 μm has been described as an example, the present invention is not limited thereto, and in some cases, a case of 200 μm or 300 μm may be described as an example.

Table 1

As shown in Table 1, it can be seen that in Example 1, that is, when the wave width W of the lenticular pattern is zero, the moiré phenomenon occurs very significantly.

In addition, as shown in Table 1, it can be seen that in Example 2, that is, when the wave width W of the lenticular pattern is 1 to 2 μm, the moiré phenomenon is weakly generated.

And, as shown in Table 1, it can be seen that in Example 3, that is, when the wave width W of the lenticular pattern is 2 to 3 μm, the moiré phenomenon does not appear.

In addition, as shown in Table 1, it can be seen that, in Example 4, that is, when the wave width W of the lenticular pattern is 5 μm, the moiré phenomenon does not appear. However, since the wave width W of the lenticular pattern is large, there is a phenomenon in which light cannot extend to the anti-light portion.

Therefore, according to the present invention, when the pitch P of the lenticular pattern is 50 μm, it can be seen that even if the wave width W of the lenticular pattern is about 4 μm, there is an effect in avoiding the moiré phenomenon.

In particular, it can be said that the larger the wave width (W) of the lenticular pattern, the more difficult it is to process.

As described above, in the liquid crystal display device to which the backlight unit having the light guide plate according to the present invention is applied, it is possible to avoid the moire phenomenon due to the pattern interference between the optical pattern of the light guide plate and the panel pixels, and the lenticular function can be maintained as it is. have.

In addition, the liquid crystal display device to which the backlight unit provided with the light guide plate according to the present invention is applied can use a product having a low sheet haze, so that the luminance can be increased.

In addition, the liquid crystal display device to which the backlight unit provided with the light guide plate according to the present invention is applied can reduce the number of sheets.

In addition, in the liquid crystal display device to which the backlight unit having the light guide plate according to the present invention is applied, the sheet can be deleted when the panel in which the sheet is integrated on the polarizing plate is applied.

Although the embodiment of the present invention has been described with reference to the drawings above, this is merely exemplary, and those skilled in the art will understand that various modifications and equivalent other embodiments are possible therefrom. . Accordingly, the protection scope of the present invention should be defined by the appended claims.

100: light guide plate 110: base layer
120: coating layer 124: optical pattern
124a, 124c: first and second convex portions 124b, 124d: first and second concave portions
W: Wave width of optical pattern P: Pitch of optical pattern
L: Wave wavelength of optical pattern H: Height of optical pattern

Claims (13)

base layer; and
It is formed on one surface of the base layer and is configured to include a coating layer including a plurality of optical patterns,
A first curved surface and a second curved surface in the form of a wave curve are formed on each of the side surface and the upper surface of the optical pattern,
The optical pattern is a lenticular pattern, a cross section of the lenticular pattern has an aspect ratio of 0.10 to 0.50, and a radius of curvature (R) of the curved surface is 10 μm to 35 μm. The light guide plate of claim 1, wherein the first curved surface on the side of the optical pattern has a structure in which first convex portions and first concave portions are repeated in left and right longitudinal directions. The light guide plate of claim 1, wherein the second curved surface on the upper surface of the optical pattern has a structure in which second convex portions and second concave portions are repeated in vertical directions. The light guide plate of claim 1, wherein the width of the first convex portion of the first curved surface of the optical pattern is 5 to 10% of the optical pattern pitch (P). delete The light guide plate of claim 1, wherein a width of the first convex portion of the first curved surface of the optical pattern is 2 to 4 μm. light guide plate;
a light source disposed on one surface of the light guide plate; and
It is disposed on the upper surface of the light guide plate and includes an optical sheet having a prism sheet,
The light guide plate includes a base layer, a coating layer formed on one surface of the base layer and including a plurality of optical patterns, and first curved surfaces and second curved surfaces in the form of wave curves are formed on side and upper surfaces of the optical pattern, respectively. including,
The optical pattern is a lenticular pattern, the cross section of the lenticular pattern has an aspect ratio of 0.10 to 0.50, and a radius of curvature (R) of the curved surface is 10 μm to 35 μm,
A width of the first convex portion of the first curved surface of the optical pattern is 2 to 4 μm. The backlight unit of claim 7 , wherein the first curved surface on the side of the optical pattern has a structure in which first convex portions and first concave portions are repeated in left and right longitudinal directions. The backlight unit of claim 7 , wherein the second curved surface on the upper surface of the optical pattern has a structure in which second convex portions and second concave portions are repeated in vertical directions. The backlight unit of claim 7 , wherein the width of the first convex portion of the first curved surface of the optical pattern is 5 to 10% of the optical pattern pitch (P). delete delete 11. A liquid crystal display comprising the backlight unit of any one of claims 7 to 10.

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