KR101844908B1 - Diffusion plate and liquid crystal display device including the same - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display, and more particularly to a diffusion plate having improved light diffusion performance.
A feature of the present invention is that a triangular-pyramidal pattern is arranged in a regular hexagon on a diffusion plate.
As a result, the light can be more effectively dispersed and diffused, the interval between the LED and the diffusion plate can be reduced to realize the thinness of the liquid crystal display device, and the defect such as the LED mura phenomenon can be prevented.
Therefore, since the interval between the LED and the LED adjacent thereto is not reduced, it is possible to solve the increase in cost and heat dissipation due to the increase in the number of LEDs, and the increase in power consumption can be solved.
Further, since the number of optical sheets is not increased, the problem that the production cost of the backlight unit increases can be solved, and the efficiency of the process can be prevented from being lowered due to an increase in the work process time in the modularization process of the liquid crystal display device have.
It is also possible to prevent the production cost from becoming high.

Description

[0001] The present invention relates to a diffusion plate and a liquid crystal display (LCD)

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display, and more particularly, to a diffusion plate having improved light diffusion performance and a liquid crystal display including the same.

2. Description of the Related Art Recently, display devices capable of visually displaying information together with development of information technology and mobile communication technology have been developed, and display devices are classified into a self-luminous display having a luminescent characteristic and an image Emitting display that can be used as a display device.

As a non-light emitting type display, an LCD (Liquid Crystal Display) device is exemplified.

Here, since the LCD device is an element that does not have a self-luminous element, a separate light source is required. Accordingly, a backlight unit having a light source on the back surface is provided to irradiate light toward the liquid crystal panel, thereby realizing an image that can be recognized only through the backlight unit.

The backlight unit uses a cold cathode fluorescent lamp (CCFL), an external electrode fluorescent lamp, and a light emitting diode (LED) as a light source.

In particular, the LED has a merit of small size, low power consumption, high reliability, and the like and is widely used as a display light source.

In general, an ordinary backlight unit is divided into an edge type and a direct type according to the arrangement structure of light sources. In the edge type, one or a pair of light sources is disposed on one side of the light guide plate , Two or two pairs of light sources are arranged on both side portions or four side portions of the light guide plate, and the direct type has a structure in which several or several light sources are disposed under the optical sheet.

In recent years, research on liquid crystal display devices that are large-sized according to consumer's demand has been actively conducted, and direct-type liquid crystal display devices are more suitable for large-sized liquid crystal display devices than edge-type liquid crystal display devices.

The direct type can be divided drive compared to the edge type, so that the image can be implemented more finely than the edge type.

1 is a cross-sectional view of a direct type liquid crystal display device using a general LED as a light source.

As shown in the figure, a typical liquid crystal display device is provided with a liquid crystal panel 10 composed of first and second substrates 12 and 14 and a backlight unit 20 behind the liquid crystal panel 10.

Here, the backlight unit 20 includes a reflection plate 22, and a plurality of LEDs 28 are arranged in parallel on the upper surface of the backlight unit 20. A diffusion plate 26 and a plurality of optical sheets 27 are located.

At this time, the lights emitted from two or three neighboring LEDs 28 are superimposed and mixed with each other, and then incident on the liquid crystal panel 10 to provide a surface light source.

The backlight unit 20 including the LED 28 and the liquid crystal panel 10 are modularized through the top cover 40, the support main 30 and the cover bottom 50, that is, the liquid crystal panel 10 and the backlight A top cover 40 for covering the front edge of the liquid crystal panel 10 and a cover bottom 50 for covering the back surface of the backlight unit 20 in a state where the edge of the unit 20 is covered with the square main support base 30 And are integrated through the support main body 30.

In recent years, the liquid crystal display device has been used in a wide range such as a desktop computer monitor and a wall-mounted television as well as a portable computer, and a thin liquid crystal display device has been actively studied with a wide display area.

Accordingly, by reducing the width of an optical gap or an air gap of the backlight unit 20, that is, the interval A between the reflection plate 22 and the diffusion plate 26, Attempts have been made to provide devices.

However, in order to supply a high-quality surface light source, which is the most important role of the backlight unit 20, to the liquid crystal panel 10, various optical designs are considered, one of which is a reflection plate 22, (A) is an important factor.

That is, when the distance A between the reflector 22 and the diffuser plate 26 is small, the light from the LED 28 is concentrated at the center of the upper portion of the LED 28, The central part is bright but causes a dark LED mura phenomenon.

This is a cause of lowering the display quality of the liquid crystal display device due to luminance reduction and luminance unevenness.

In order to solve the above problem, it is necessary to increase the number of LEDs 28 to increase the cost of the LED 28 and reduce the space between the LED 28 and the adjacent LED 28, And furthermore, the power consumption is increased.

Further, a lightweight liquid crystal display device can not be realized.

However, if the number of the optical sheets 27 thus stacked increases, the image quality is improved, but the production cost of the backlight unit 20 And the work process time is increased in the modularization process of the liquid crystal display device, thereby reducing the efficiency of the process and raising the manufacturing cost.

This also hinders the thinness and light weight of the liquid crystal display device.

SUMMARY OF THE INVENTION It is a first object of the present invention to provide a lightweight and thin liquid crystal display device and to solve defects such as LED mura and the like.

It is a second object of the present invention to prevent the problem of deterioration of display quality due to unevenness of luminance of a liquid crystal display device.

In order to achieve the above-mentioned object, the present invention provides a liquid crystal display comprising: a reflection plate; A light source positioned on the reflection plate; A diffuser plate positioned above the light source and having a plurality of triangular-pyramidal patterns protruding and arranged; A plurality of optical sheets positioned on the diffusion plate; And a liquid crystal panel disposed on the plurality of optical sheets, wherein the six neighboring triangular-pyramidal patterns form a regular hexagonal pattern in a plan view.

In this case, the hexagonal pattern is arranged such that the edges of six bottom surfaces of the plurality of triangular-pyramidal patterns meet at a central portion, and the length of one side of the bottom surface of the triangular-pyramidal pattern and the height of the triangular- And the bottom surface of the triangular-pyramidal pattern has a height of 8 to 800 mu m.

At this time, the length of one side of the bottom face of the triangular-pyramidal pattern is 344 占 퐉, the height of the bottom face of the triangular pyramid pattern is 300 占 퐉, and the height of the triangular pyramid pattern is 150 占 퐉.

A light guide plate is formed on the reflection plate, and the light source is arranged on one side or both sides of the light guide plate.

The present invention also relates to a semiconductor device comprising: a support layer; And a polygonal pattern layer formed on one surface of the support layer and having a plurality of triangular-pyramidal patterns protruding from the support layer so as to be adjacent to each other, wherein the six triangular- Provides a diffuser plate in a planar hexagonal pattern.

In this case, the hexagonal pattern is arranged such that the edges of six bottom surfaces of the plurality of triangular-pyramidal patterns meet at a central portion, and the length of one side of the bottom surface of the triangular-pyramidal pattern and the height of the triangular- And the bottom surface of the triangular-pyramidal pattern has a height of 8 to 800 mu m.

Here, the length of one side of the bottom surface of the triangular pyramidal pattern is 344 mu m, and the height of the bottom surface of the triangular pyramid pattern is 300 mu m.

The height of the triangular-pyramidal pattern is 150 mu m.

In addition, in the present invention, the triangular-pyramidal side surfaces are concave in a direction facing each other, and the length of one side of the bottom surface of the triangular pyramid pattern is 350 μm.

At this time, the height of the triangular-pyramidal pattern is 110 mu m, and the triangular-pyramidal side surfaces are curved concavely in the directions opposite to each other.

The length of one side of the bottom surface of the triangular-pyramidal pattern is 350 占 퐉, and the height of the triangular-pyramidal pattern is 110 占 퐉.

As described above, according to the present invention, by arranging the triangular-pyramidal pattern on the diffuser plate into a regular hexagon, it is possible to disperse and diffuse the light more effectively, thereby reducing the interval between the reflector and the diffuser plate, And it is possible to prevent defects such as LED mura phenomenon.

Therefore, since there is no need to reduce the interval between the LEDs and the adjacent LEDs, it is possible to solve the problem of cost increase and heat dissipation due to an increase in the number of LEDs, and it is also possible to solve the increase in power consumption.

In addition, since the number of optical sheets is not increased, the problem that the production cost of the backlight unit is increased can be solved, and the efficiency of the process is decreased due to an increase in the work process time in the modularization process of the liquid crystal display device There is an effect that can be prevented.

In addition, the manufacturing cost can be prevented from being increased.

1 is a sectional view of a direct-type liquid crystal display device using a general LED as a light source.
2 is an exploded perspective view illustrating a liquid crystal display device according to an embodiment of the present invention.
3 is a cross-sectional view schematically showing a modularized view of the liquid crystal display device according to the embodiment of the present invention shown in Fig. 2;
4A is a perspective view schematically showing a diffusion plate according to an embodiment of the present invention.
Figure 4b is a cross-sectional view of Figure 4a.
Fig. 4c is a plan view showing a polygonal pattern of the diffuser plate of Fig. 4a. Fig.
5A is an experimental result showing the occurrence of an LED mura phenomenon in which the interval between the reflection plate and the diffusion plate is 33.0 mm.
FIG. 5B is an experimental result showing the occurrence of LED mura phenomenon in which the interval between the reflection plate and the diffusion plate is 17.1 mm.
5c is an experimental result showing the occurrence of an LED mura phenomenon with a gap of 17.1 mm between the reflection plate and the diffuser according to the embodiment of the present invention.
6A is a perspective view schematically showing a diffuser plate according to a second embodiment of the present invention;
6B is a sectional view of Fig. 6A. Fig.
Fig. 6C is a plan view showing a polygonal pattern of the diffuser plate of Fig. 6A. Fig.
7A to 7B are experimental results showing the occurrence of LED mura phenomenon according to the interval between the reflection plate and the diffusion plate.

Hereinafter, embodiments according to the present invention will be described in detail with reference to the drawings.

2 is an exploded perspective view illustrating a liquid crystal display device according to an embodiment of the present invention.

The liquid crystal display device 100 includes a liquid crystal panel 110, a backlight unit 120, a support main body 130, a cover bottom 150, and a top cover 140.

First, the liquid crystal panel 110 plays a key role in image display and includes first and second substrates 112 and 114 which are bonded to each other with a liquid crystal layer interposed therebetween.

At this time, a plurality of gate lines and data lines intersect with each other on the inner surface of the first substrate 112, which is usually referred to as a lower substrate or an array substrate, although not clearly shown in the figure, And a thin film transistor (TFT) is provided at each intersection point and is connected in a one-to-one correspondence with the transparent pixel electrode formed in each pixel.

On the inner surface of the second substrate 114 called an upper substrate or a color filter substrate, color filters of red (R), green (G), and blue (B) And a black matrix for covering non-display elements such as a gate line, a data line, and a thin film transistor. In addition, a transparent common electrode covering these elements is provided.

The printed circuit boards 118a and 118b are connected to at least one edge of the liquid crystal panel 110 via a connection member 116 such as a flexible circuit board so that the side surfaces or the cover bottoms 150).

Although not clearly shown in the drawing, an upper and a lower alignment film (not shown) for determining the initial alignment direction of the liquid crystal are interposed between the two substrates 112 and 114 of the liquid crystal panel 110 and the liquid crystal layer A seal pattern is formed along the edges of both substrates 112 and 114 to prevent leakage of the liquid crystal layer filled therebetween.

At this time, upper and lower polarizers (not shown) are attached to the outer surfaces of the first and second substrates 112 and 114, respectively.

A backlight unit 120 for supplying light is provided on a back surface of the liquid crystal panel 110 so that a difference in transmittance represented by the liquid crystal panel 110 is externally expressed.

The backlight unit 120 includes an LED assembly 128, a polygonal pattern diffuser plate 200 interposed on the LED assembly 128, and an optical sheet 127 interposed therebetween.

The LED assembly 128 described above includes a PCB 128b arranged to have a constant spacing along the longitudinal inner surface of the cover bottom 150 and a plurality of LEDs 128a mounted on each of them.

Here, the plurality of LEDs 128a emit light having colors of red (R), green (G), and blue (B), respectively. By lighting the plurality of RGB LEDs 128a at once, white light Can be implemented.

On the other hand, the LED 128a that implements white light may be composed of a blue LED chip (not shown) and a yellow phosphor, and the yellow phosphor may include cerium (Ce) -doped yttrium aluminum (Al) garnet YAG: Ce (T3Al5O12: Ce) based phosphor is preferably used.

When a UVLED chip is used, the phosphor (not shown) is composed of three phosphors of red (R), green (G), and blue (B) The luminescent color can be selected by controlling the compounding ratio of the red (R), green (G), and blue (B) phosphors (not shown).

Here, the red (R) phosphor is a YOX (Y2O3: EU) based phosphor composed of a compound of yttrium oxide (Y2O3) and europium (EU) having a main wavelength of 611 nm and the green (G) (LaPo4: Ce, Tb) phosphor, which is a compound of phosphorus (Po4) and lanthanum (La) and terbium (Tb) having a dominant wavelength as a main wavelength, and a blue phosphor (B) BAM blue (BaMgAl 10 O 17: EU) based phosphor which is a compound of Eu and Eu and a substance of magnesium oxide and aluminum oxide are preferably used.

Here, the dominant wavelength is the wavelength at which the highest luminance is generated in red (R), green (G), and blue (B), respectively, as the dominant wavelength of the phosphor.

On the other hand, by using the LED 128a constituted by an LED chip (not shown) that emits all the colors of RGB, it is possible to realize white light in each LED 128a, or to realize a white color including a white- The emitting LED 128a may also be used.

The PCB 128b on which the plurality of LEDs 128a are mounted is a metal core printed circuit board having a heat dissipating function and a heat sink (not shown) is provided on the back surface of the MCPCB 128b It is possible to transfer heat from the LED 128a of the light emitting diode 128a to the outside.

The backlight unit 120 includes a plurality of through holes 123 through which a plurality of LEDs 128a can pass so that the PCB 128b except for the plurality of LEDs 128a and the entire inner surface of the cover bottom 150 And includes a reflective white or silver reflector 122.

A polygonal pattern diffuser plate 200 and an optical sheet 127 for uniformity of luminance are positioned above the LEDs 128a exposed through the through holes 123 of the reflector 122.

At this time, the polygonal pattern diffuser 200 of the present invention disperses and diffuses linear light emitted from the plurality of LEDs 128a, thereby realizing a more uniform surface light source and increasing color mixing.

The plurality of optical sheets 127 positioned on the polygonal pattern diffuser plate 200 are formed of a diffusing sheet and at least one light condensing sheet or the like and have various functionalities such as a reflective polarizing film called a dual brightness enhancement film (DBEF) Sheet may be included.

Therefore, the white light emitted from the plurality of LEDs 128a passes through the polygon pattern diffuser plate 200 and the optical sheet 127 in order, and then enters the liquid crystal panel 110, and the liquid crystal panel 110 The high-luminance image is displayed externally.

The liquid crystal panel 110 and the backlight unit 120 are modularized through a top cover 140, a support main 130 and a cover bottom 150. The top cover 140 is disposed on the upper surface and the side surface of the liquid crystal panel 110, And a top cover 150 is opened to display an image formed on the liquid crystal panel 110. The top cover 150 may be formed as a rectangular frame having a rectangular cross section.

The cover bottom 150 which is based on the assembly of the entire liquid crystal display device with the liquid crystal panel 110 and the backlight unit 120 mounted thereon is formed into a square plate shape, And a pair of side supports 129 in the form of a pair of bars joined to the edges of the cover bottom 150. The remaining two edges of the cover bottom 150 are bent at an oblique angle so as to have a height equal to the height, Thereby forming a predetermined space in which the battery 120 can be seated.

The support main body 130 which is mounted on the cover bottom 150 and has a rectangular frame shape covering the edges of the liquid crystal panel 110 and the backlight unit 120 is combined with the top cover 140 and the cover bottom 150.

The top cover 150 may be referred to as a case top or a top case. The support main 130 may be referred to as a guide panel or a main support or a mold frame. The cover bottom 150 may be referred to as a bottom cover.

The liquid crystal display device 100 of the present invention as described above is modularized as compared with the conventional liquid crystal display device, which will be described in detail with reference to FIG. 3 below.

3 is a cross-sectional view schematically showing a modularized view of the liquid crystal display device according to the embodiment of the present invention shown in FIG.

As shown in the figure, the liquid crystal display of the present invention has a reduced overall height as compared with the conventional liquid crystal display device. This is because an optical gap or an air gap (see FIG. 2) air gaps) have been reduced.

That is, in the backlight unit (120 in FIG. 2) of the present invention, the interval A 'between the reflection plate 122 and the polygonal pattern diffuser plate 200 is reduced as compared with the conventional interval (A in FIG.

At this time, the interval A 'between the reflection plate 122 of the present invention and the polygonal pattern diffuser plate 200 is reduced by about 1/2 compared to the conventional interval (A' in FIG. 1). (A '= 1 / 2A)

In addition, the present invention does not cause the LED mura phenomenon in spite of the decrease in the distance A 'between the LED 128a and the polygonal pattern diffuser 200, The polygon pattern diffuser 200 according to the embodiment of the present invention substantially maintains the luminance of the LED 128a and distributes and diffuses the light more effectively.

- First Embodiment -

FIG. 4A is a perspective view schematically showing a diffusion plate according to the first embodiment of the present invention, FIG. 4B is a sectional view of FIG. 4A, and FIG. 4C is a plan view of a polygonal pattern of the diffusion plate of FIG.

The polygonal pattern diffusing plate 200 according to the first embodiment of the present invention has haze characteristics. Haze characteristic means that, when light passes through a transparent material, depending on the type of material, The haze characteristic value is measured according to the following formula (1). ≪ EMI ID = 1.0 >

(%) = ({Total light transmittance - straight light amount} / {total light transmittance of light}) 100 (1)

If the haze value is less than 30%, the viewing angle becomes low because the light diffusivity is low. If the haze value is more than 90%, the light transmittance is low and the luminance is low. .

The haze value of the polygonal pattern diffuser 200 may include a diffusion component such as a bead (not shown), or may include fine patterns (not shown) on the bottom surface without including beads Can be configured.

At this time, the beads (not shown) disperse the light incident on the polygonal pattern diffuser 200, thereby preventing the light from being partially concentrated.

The polygonal pattern diffuser plate 200, which does not include beads (not shown), is characterized in that light scattering angles can be adjusted according to the shape of a fine pattern (not shown). A fine pattern (not shown) an elliptical pattern, and a polygon pattern. By using a hologram pattern, the light incident on the interference pattern is refracted in an asymmetrical direction, It can be made to diffuse at the photograph angle.

Thereby, the light is dispersed to prevent the light from being partially concentrated.

Particularly, the polygonal pattern diffuser 200 of the present invention disperses and diffuses light through the polygonal pattern layer 220 more.

4A to 4C, the polygonal pattern diffusing plate 200 according to the first embodiment of the present invention may be formed of polycarbonate (PC), transparent acryl resin, PS (polystryrene), heat resistant PS, A support layer 210 made of PMMA (polymethylmethacrylate), a thermoplastic resin such as PET (polyethylene terephthalate), and a polygonal pattern layer 220 for dispersing and diffusing light on the upper surface of the support layer 210.

The polygonal pattern layer 220 formed on the upper surface of the support layer 210 may be formed of the same material as the support layer 210 or may be formed of a photosensitive material such as photoresist. Shaped pattern 230 is protruded and arranged from the support layer 210.

The plurality of triangular-pyramidal shapes are three-dimensional polyhedrons formed by one bottom surface and three side surfaces of a triangle, and three side surfaces meet at one vertex. The plurality of triangular- And are closely arranged so that there is no empty space between neighboring triangular-pyramidal patterns 230. In this case,

The triangular-pyramidal pattern 230 may be formed to have a length d of one side of the bottom surface of 10 to 1000 탆, and most preferably, a length d of one side of the bottom surface of 344 탆.

The height h of the bottom surface may be formed to be 8 to 800 占 퐉 smaller than the length d of one side of the bottom surface of the triangular pyramid pattern 230. Most preferably, Mu m.

The height H of the triangular-pyramid pattern 230 protruding from the support layer 210 may be 10 to 1000 占 퐉, and most preferably, the height H is 150 占 퐉.

In particular, as shown in FIG. 4C, among the plurality of triangular-pyramidal patterns 230, the six triangular-pyramid patterns 230 adjacent in the longitudinal direction and the transverse direction are formed such that the edges of the six bottom surfaces meet at one central portion, And are arranged to form one regular hexagonal pattern.

That is, the six triangular-pyramid patterns 230 are arranged such that a pair of triangular-pyramid patterns 230 facing each other with respect to the central portion of the regular hexagonal pattern are point-symmetrical with respect to each other. At this time, each regular hexagonal pattern is arranged to share some triangular-pyramidal pattern 230 with another neighboring regular hexagonal pattern.

That is, the hexagonal pattern of the polygonal pattern layer 220 has a honeycomb shape.

Accordingly, in the polygon pattern diffuser 200 of the present invention, light is diffused through the haze component of the support layer 210 and the brightness of the LED (128a in FIG. 3) is substantially maintained through the polygonal pattern layer 220, Are more effectively dispersed and diffused.

Thus, even though the distance (A 'in FIG. 3) between the LED (128a in FIG. 3) and the polygonal pattern diffuser 200 is smaller than the conventional spacing (A in FIG. 1), LED mura phenomenon Can be prevented.

This can be confirmed with reference to Figs. 5A to 5C.

5A is an experimental result showing the occurrence of an LED mura phenomenon in a state in which the interval between the reflection plate and the diffusion plate is 33.0 mm. Figs. 5B to 5C show the results of experiments FIG. 5B shows a case where a general diffusion plate is used, and FIG. 5C shows an experimental result when a polygonal pattern diffuser according to an embodiment of the present invention is used.

5A and FIG. 5C are compared with each other. As shown in FIG. 5C, the LED mura phenomenon does not occur even though the gap between the reflection plate and the diffusion plate is reduced as compared with FIG. 5A.

That is, in the liquid crystal display of the present invention, the polygonal pattern diffuser of the present invention can more effectively disperse and diffuse the light compared to a general diffuser, even when the gap between the reflector and the diffuser is reduced by about 16.0 mm By spreading, it is possible to prevent the LED mura phenomenon from occurring.

This prevents LED mura phenomenon from occurring and reduces the thickness of the backlight unit.

5B and 5C, it can be seen that when a general diffusion plate is used, LED mura phenomenon occurs when the gap between the reflection plate and the diffusion plate is reduced. However, in the case of using the polygon according to the embodiment of the present invention, It can be confirmed that the LED mura phenomenon does not occur even if the interval between the reflection plate and the diffusion plate is reduced when the pattern diffusion plate is included.

This is also because the polygonal pattern diffuser of the present invention disperses and diffuses light more effectively than a general diffusion plate.

As described above, the liquid crystal display device of the present invention arranges the triangular pyramidal pattern on the diffuser plate so as to form a regular hexagon, thereby more effectively dispersing and diffusing the light, thereby reducing the interval between the reflection plate and the diffuser plate, Thinness can be realized, but defects such as LED mura phenomenon can be prevented.

Therefore, since the interval between the LED and the LED adjacent thereto is not reduced, it is possible to solve the increase in cost and heat dissipation due to the increase in the number of LEDs, and the increase in power consumption can be solved.

Further, since the number of optical sheets is not increased, the problem that the production cost of the backlight unit increases can be solved, and the efficiency of the process can be prevented from being lowered due to an increase in the work process time in the modularization process of the liquid crystal display device have.

It is also possible to prevent the production cost from becoming high.

In this case, a fluorescent lamp such as a cathode cathode fluorescent lamp or an external electrode fluorescent lamp may be used in addition to the LED as a light source of the backlight unit.

In the above description, the polygonal pattern diffuser according to the present invention can be utilized as a liquid crystal display device, but it can be applied to an edge type. In this case, the light guide plate can further be interposed on the reflector .

- Second Embodiment -

6A is a perspective view schematically showing a diffusing plate according to a second embodiment of the present invention, FIG. 6B is a cross-sectional view of FIG. 6A, and FIG. 6C is a plan view showing a polygonal pattern of the diffusing plate of FIG. 6A.

As shown in the figure, the polygonal pattern diffusing plate 300 according to the second embodiment of the present invention may be formed of polycarbonate, transparent acryl resin, polystryrene, heat resistant PS, polymethylmethacrylate (PMMA), thermoplastic resin A supporting layer 310 made of PET (polyethylene terephthalate) or the like, and a polygonal pattern layer 320 for dispersing and diffusing light on the upper surface of the supporting layer 310.

Here, the support layer 310 has a haze characteristic, and the haze characteristic can realize a desired luminance and viewing angle through adjustment of the haze value.

That is, when the haze value is 30% or less, the light diffusing rate is low and the viewing angle becomes narrow. When the haze value is 90% or more, the light transmittance is low and the luminance is low.

 The haze value of the supporting layer 310 may be formed by including a diffusion component such as a bead (not shown) or by forming a fine pattern (not shown) on the lower surface without including a bead have.

At this time, the bead (not shown) disperses the light incident on the support layer 310, thereby preventing the light from being partially concentrated.

The support layer 310, which does not include a bead (not shown), is characterized in that the light scattering angle can be controlled according to the shape of a fine pattern (not shown). The fine pattern (not shown) is an elliptical pattern And a polygon pattern. By using a hologram pattern, the light incident on the interference pattern is refracted in an asymmetrical direction, so that the condensed light is reflected at a more inclined angle To be diffused.

Thereby, the light is dispersed to prevent the light from being partially concentrated.

Particularly, the polygon pattern diffusing plate 300 according to the second embodiment of the present invention disperses and diffuses the light through the polygonal pattern layer formed on the upper surface of the support layer 310.

The polygonal pattern layer 320 formed on the upper surface of the support layer 310 may be formed of the same material as the support layer 310 or may be formed of a photosensitive material such as photoresist, The triangular-pyramidal pattern 330 is protruded and arranged from the supporting layer 310.

Here, the plurality of triangular-pyramidal shapes are three-dimensional polyhedrons formed by one bottom face and three side faces of a triangle, and three side faces meet at one vertex. The plurality of triangular- And the adjacent triangular-pyramidal patterns 330 are closely arranged so that there is no empty space.

The triangular-pyramidal pattern 330 may be formed to have a length d 'of one side of the bottom surface of 10 to 1000 μm, and it is most preferable that the length d' of one side of the bottom surface is 350 μm .

The height h 'of the bottom surface can be formed to be 8 to 800 μm smaller than the length d' of one side of the bottom surface of the triangular-pyramid pattern 330. Most preferably, the height h ' ) Is preferably 300 mu m.

The height H 'of the triangular-pyramidal pattern 330 protruding from the support layer 310 can also be set to 10 to 1000 μm, and it is most preferable that the height H' is 110 μm .

6C, six triangular-pyramidal patterns 330 adjacent to each other in the longitudinal direction and the transverse direction of the plurality of triangular-pyramidal patterns 330 are formed such that the edges of the six bottom surfaces meet at one central portion, And are arranged to form one regular hexagonal pattern.

That is, the six triangular-pyramid patterns 330 are arranged such that a pair of triangular-pyramid patterns 330 opposed to each other with respect to the central portion of the regular hexagonal pattern are point-symmetric with respect to each other. At this time, each regular hexagonal pattern is arranged to share some triangular-pyramidal pattern 330 with another neighboring regular hexagonal pattern.

That is, the hexagonal pattern of the polygonal pattern layer 320 has a honeycomb shape.

In this case, the triangular-pyramidal pattern 330 according to the second embodiment of the present invention is formed such that three side faces that meet at one vertex are concave in a direction facing each other.

Accordingly, the adjacent triangular-pyramidal pattern 330 has the side surfaces facing each other in an elliptical shape S in plan view.

The polygonal pattern diffuser 300 of the present invention diffuses light through the haze component of the support layer 310 and substantially maintains the brightness of the LED (128a in FIG. 3) through the polygonal pattern layer 320, Are more effectively dispersed and diffused.

Particularly, since the sides of the triangular pyramidal pattern 330 are formed to be concave in a direction facing each other, the effect of dispersing and diffusing light is further maximized.

Thus, even though the interval (A 'in FIG. 3) between the LED (128a in FIG. 3) and the polygonal pattern diffuser 300 is smaller than the conventional spacing (A in FIG. 1), LED mura phenomenon Can be prevented.

FIG. 7A is a graph showing the results of an experiment showing whether or not an LED mura phenomenon occurs in a state in which the interval between the reflection plate and the diffusion plate is 24 mm. FIG. 7B is a graph showing the distance between the diffusion plate and the reflection plate according to the second embodiment of the present invention 20 mm in the case of the LED mura phenomenon.

As shown in FIG. 7B, it can be seen that although the gap between the reflection plate and the diffusion plate is reduced as compared with FIG. 7A, no LED mura phenomenon occurs.

In other words, the liquid crystal display of the present invention is advantageous in that the polygonal pattern diffusing plate of the present invention disperses and diffuses light more effectively than a general diffusing plate even when the gap between the reflector and the diffusing plate is reduced by about 4 mm It is possible to prevent the LED mura phenomenon from occurring.

This prevents LED mura phenomenon from occurring and reduces the thickness of the backlight unit.

As described above, in the liquid crystal display device of the present invention, the triangular-pyramidal pattern is arranged on the diffusion plate so as to form a regular hexagon, and the sides of the triangular-pyramid pattern are concavely curved in directions facing each other, And it is possible to reduce the interval between the reflection plate and the diffusion plate, thereby realizing the thinness of the liquid crystal display device and preventing defects such as LED mura phenomenon.

Therefore, since the interval between the LED and the LED adjacent thereto is not reduced, it is possible to solve the increase in cost and heat dissipation due to the increase in the number of LEDs, and the increase in power consumption can be solved.

Further, since the number of optical sheets is not increased, the problem that the production cost of the backlight unit increases can be solved, and the efficiency of the process can be prevented from being lowered due to an increase in the work process time in the modularization process of the liquid crystal display device have.

It is also possible to prevent the production cost from becoming high.

The present invention is not limited to the above-described embodiments, and various modifications may be made without departing from the spirit of the present invention.

200: polygonal pattern diffuser plate
210: support layer, 220: polygonal pattern layer, 230: triangular-pyramid pattern

Claims (19)

A reflector;
A light source positioned on the reflection plate;
A diffuser plate positioned above the light source and having a plurality of triangular-pyramidal patterns protruding and arranged;
A plurality of optical sheets positioned on the diffusion plate;
And a liquid crystal panel
Wherein the six triangular pyramidal patterns adjacent to each other of the plurality of triangular pyramidal patterns form a regular hexagonal pattern in a planar manner,
Wherein the side surfaces of the triangular-pyramidal pattern are concave and curved in directions opposite to each other, and the side surfaces of the triangular-pyramidal patterns adjacent to each other are planarly elliptical.
The method according to claim 1,
Wherein the regular hexagonal pattern is arranged such that edges of six bottom surfaces of the plurality of triangular-pyramidal patterns meet at a central portion.
delete delete delete delete The method according to claim 1,
Wherein a light guide plate is formed on the reflection plate, and the light source is arranged on one side or both sides of the light guide plate.
delete delete delete delete delete delete delete The method according to claim 1,
And the length of one side of the bottom surface of the triangular-pyramidal pattern is 350 m.
The method according to claim 1,
And the height of the triangular pyramid pattern is 110 mu m. delete delete delete

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