KR101317902B1 - Multi-optical sheet and liquid crystal display device including the same - Google Patents

Abstract

The present invention relates to a liquid crystal display device, and more particularly, to a composite light collecting sheet having improved light efficiency and viewing angle characteristics.
A feature of the present invention is that the first condensing part including the first lens layer and the first lens layer made of a plurality of prism acids on the first support layer and the first support layer and the second support layer have adhesive properties, and the plurality of prism acids are formed to have different heights. It is to provide a composite light collecting sheet in which the second light collecting unit is integrally bonded.
Through this, it is possible to realize high brightness and to reduce the overall thickness of the optical sheets compared to applying a plurality of light collecting sheets, respectively, to realize a light weight and thin liquid crystal display device, and improve the efficiency of the modularization process of the liquid crystal display device You can.
In addition, it is possible to minimize the light loss due to the side lobe, it is possible to prevent the occurrence of spectral mura (hot band) or (hot band).

Description

Multi-optical sheet and liquid crystal display device including the same}

The present invention relates to a liquid crystal display device, and more particularly, to a composite light collecting sheet having improved light efficiency and viewing angle characteristics.

2. Description of the Related Art In recent years, the display field has rapidly developed in line with the information age. In response to this trend, a flat panel display device (FPD) having a thinness, light weight, A plasma display panel (PDP), an electroluminescence display device (ELD), and a field emission display device (FED) : CRT).

Among them, liquid crystal display devices are used most actively in the field of notebooks, monitors, TVs, etc. because of their excellent contrast ratio and high contrast ratio, and liquid crystal display devices do not have their own light emitting elements. Will be required.

Accordingly, a backlight unit having a light source is provided on a rear surface of the liquid crystal panel to irradiate light toward the front of the liquid crystal panel, thereby realizing an image of identifiable luminance.

Meanwhile, a general backlight unit is classified into a side light method and a direct type method according to an arrangement of light sources. The side light method is a structure in which one or a pair of light sources is disposed at one side of the light guide plate. It has, or two or two pairs of light sources have a structure arranged on each side of the light guide plate, the direct type has a structure in which several light sources are arranged under the optical sheet.

Here, the side light method is easier to manufacture than the direct type method, and has the advantages of lighter weight and lower power consumption than the direct type.

1 is a cross-sectional view of a liquid crystal display device using a general side light type backlight unit.

As shown, a typical liquid crystal display device includes a liquid crystal panel 10, a backlight unit 20, a support main 30, a cover bottom 50, and a top cover 40.

The liquid crystal panel 10 is a part that plays a key role in image expression and is composed of first and second substrates 12 and 14 bonded to each other with a liquid crystal layer interposed therebetween. A printed circuit board (not shown) is connected to each of the two adjacent edges of the liquid crystal panel 10 through a connection member (not shown).

In this case, polarizing plates 19a and 19b for selectively transmitting only specific light are attached to each outer surface of the first second substrates 12 and 14 of the liquid crystal panel 10.

And, the rear of the liquid crystal panel 10 and the LED assembly 29 arranged along the longitudinal direction of at least one side edge of the support main 30, the white or silver reflecting plate 25 seated on the cover bottom 50 and The backlight unit 20 includes a light guide plate 23 mounted on the reflective plate 25 and an optical sheet 21 interposed therebetween.

In this case, the plurality of optical sheets 21 includes a diffusion sheet and a light collecting sheet.

Here, the LED assembly 29 is composed of a plurality of LEDs 29a and a PCB 29b on which the plurality of LEDs 29a are mounted.

The liquid crystal panel 10 and the backlight unit 20 are covered with a top cover 40 covering the upper edge of the liquid crystal panel 10 in a state where the edge is surrounded by the support main 30 having a rectangular frame shape, And the cover bottoms 50 are integrally joined to each other through the support main body 30.

Therefore, the light emitted from the LED assembly 29 is incident on the light guide plate 23 and then refracted in the direction of the liquid crystal panel 10. The light emitted from the LED assembly 29 is processed to a high quality of uniform luminance while passing through the optical sheet 21 to the liquid crystal panel 10. Incident, the liquid crystal panel 10 thereby displays an image to the outside.

On the other hand, the backlight unit 20 of the liquid crystal display device has recently used a plurality of light condensing sheets in order to implement high brightness by the consumer's demand, it is possible to implement a high brightness by using a plurality of light collecting sheets in this way, The thin and light weight of the liquid crystal display device is impaired.

In addition, the work process time is increased in the modularization process of the liquid crystal display, which causes a problem that the efficiency of the process is lowered.

In addition, as the light collecting sheets are overlapped with each other, surface damage of the prism acid of the light collecting sheet positioned below may occur. In this case, the light collecting performance of the light collecting sheet may be degraded, which is caused by the decrease in brightness and the unevenness of light. It becomes a cause of degrading the display quality of a liquid crystal display device.

The present invention has been made to solve the above problems, and a first object of the present invention is to provide a liquid crystal display device having high brightness.

A second object of the present invention is to provide a light collecting sheet capable of preventing damage of the prism acid. In this way, the present invention aims to prevent display quality deterioration due to uneven brightness of the liquid crystal display device. do.

In addition, the fourth object of the present invention is to reduce the assembly time and the material cost in the modularization process of the liquid crystal display device while at the same time implementing the light weight and thinness of the liquid crystal display device.

In order to achieve the above object, a liquid crystal panel; And a light source located under the liquid crystal panel; A first collector including a first lens layer on the light source, the first lens layer having a plurality of first prism acids formed on one surface facing the liquid crystal panel, and a first diffusion layer on the other surface opposite to one surface on which the first prismatic acids are formed; A second light collecting portion including a light portion and a second lens layer formed with a plurality of second prism acids having a first height and attached to the first diffusion layer and a plurality of third prism acids having a second height lower than the first height It provides a liquid crystal display device comprising a composite light collecting sheet comprising a.

In addition, the present invention and the liquid crystal panel; and a light source located below the liquid crystal panel; A first collector including a first lens layer on the light source, the first lens layer having a plurality of first prism acids formed on one surface facing the liquid crystal panel, and a first diffusion layer on the other surface opposite to one surface on which the first prismatic acids are formed; According to an aspect of the present invention, there is provided a liquid crystal display including a light collecting part and a second light collecting part including a light collecting part and a second light collecting part including a second lens layer formed with a plurality of second prism acids overlapping the first diffusion layer.

In this case, the second lens layer has an adhesive property, and the plurality of first to third prism acids are formed of first and second inclined surfaces forming corners of 80 to 90 °, respectively, and the first and second lens layers. The refractive index of is from 1.57 to 1.58.

The first and second light collecting parts include first and second support layers each made of PMMA (polymethylmethacrylate), polyethylene terephthalate (PET), and the like, and the first lens layer protrudes from the first support layer. The first diffusion layer is formed on the rear surface of the first support layer, the second lens layer is arranged to protrude from the second support layer, and the number of the plurality of second prism acids is the number of the second lens layer. 30% of the first and second prism acids.

And, the height of the plurality of third prism acid is in the range of 10 to 90% of the height of the plurality of second prism acid, the spacing of the plurality of second prism acid and the spacing of the plurality of third prism acid is 40 ~. 90 micrometers.

Here, a second diffusion layer is provided on a rear surface of the second support layer, and the plurality of first and second prism acids are formed of first and second inclined surfaces forming corners of 80 to 90 °, respectively. The refractive index of the two lens layers is from 1.57 to 1.58.

The first and second light collecting parts may include first and second support layers each made of PMMA (polymethylmethacrylate), polyethylene terephthalate (PET), and the like, and the first lens layer may protrude from the first support layer. The first diffusion layer is formed on the rear surface of the first support layer, the second lens layer is arranged to protrude from the second support layer, and the second lens layer is divided into a plurality of prism mountains, and the plurality of prisms Each of the peaks is formed by overlapping slopes of the plurality of second prism mountains with each other.

The second prism is located at the same height as the apex of the edge protruding from the second support layer, and the first and second inclined surfaces of the plurality of third prism have the same length or have different lengths. Has

In addition, a reflective plate is positioned below the composite light collecting sheet, and a light guide plate is formed on the reflective plate, and the light source is arranged on one side or both sides of the light guide plate.

The present invention also provides a first support layer, a first lens layer formed on one surface of the first support layer and protrudingly formed such that a plurality of first prism acids are arranged adjacent to each other on the first support layer, and the first support layer. A first light collecting part including a first diffusion layer formed on a rear surface thereof; A second support layer, a plurality of second prism acids formed on one surface of the second support layer, attached to the first diffusion layer, and having a first height, and a plurality of third prisms having a second height lower than the first height; Provided is a composite light collecting sheet including a second light collecting part including a second lens layer having an acid formed therein.

In addition, a first lens layer and a first lens layer formed on one surface of the first support layer, protruding so that a plurality of first prism acid is arranged adjacent to each other on the first support layer, and formed on the rear surface of the first support layer A first condenser including a first diffusion layer; A composite light collecting sheet including a second condensing part including a second support layer and a second lens layer formed on one surface of the second support layer and attached to the first diffusion layer and having a plurality of second prism acids formed to overlap each other. To provide.

As described above, according to the present invention, the first condenser and the second support layer including the first lens layer made of a plurality of prism acids on the first support layer and the first support layer have adhesive properties and a plurality of prism acids By providing a composite light condensing sheet in which the second light converging part formed to have a different height is integrally bonded, there is an effect of reducing the overall thickness of the optical sheets as compared to applying a plurality of light condensing sheets, respectively, while achieving high brightness.

Through this, there is an effect to implement a lightweight and thin liquid crystal display device, it is possible to improve the efficiency of the modularization process of the liquid crystal display device.

In addition, it is possible to minimize the light loss due to the side lobe, there is an effect that can prevent the occurrence of spectral mura (hotrum) or (hot band).

1 is a cross-sectional view of a liquid crystal display device using a general side light type backlight unit.
2 is an exploded perspective view schematically illustrating a liquid crystal display device according to an embodiment of the present invention.
3 is a cross-sectional view schematically showing a composite light collecting sheet according to a first embodiment of the present invention.
4 is a cross-sectional view schematically showing a composite light collecting sheet according to a second embodiment of the present invention.
5 is a cross-sectional view schematically showing a composite light collecting sheet according to a third embodiment of the present invention.
6A to 6B are cross-sectional views schematically showing a path of light passing through the second light collecting part of the composite light collecting sheet.
7 is a schematic view of a composite light collecting sheet manufacturing apparatus according to a third embodiment of the present invention.

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

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

As shown, the liquid crystal display according to the exemplary embodiment of the present invention includes a liquid crystal panel 110 and a backlight unit 120, and supports main body 130 for modularizing the liquid crystal panel 110 and the backlight unit 120. ) And the cover bottom 150, the top cover 140.

Here, the liquid crystal panel 110 plays a key role in image expression and includes a first substrate 112 and a second substrate 114 bonded to each other with the liquid crystal layer interposed therebetween.

At this time, although not shown in the drawing, a plurality of gate lines and data lines intersect on the inner surface of the first substrate 112 called an array substrate, and a pixel is defined, and a thin film transistor is formed at each intersection point. TFTs are provided and connected one-to-one with the transparent pixel electrodes formed in each pixel.

An inner surface of the second substrate 114 called a color filter substrate is a color filter of red (R), green (G), and blue (B) color, and each of them is an example corresponding to each pixel. In addition, a black matrix covering the gate line, the data line, and the thin film transistor is provided. In addition, color filters of red (R), green (G), and blue (B) colors and transparent common electrodes covering the black matrix are provided.

A polarizing plate (not shown) for selectively transmitting only specific light is attached to the outer surfaces of the first and second substrates 112 and 114, respectively.

Along the at least one edge of the liquid crystal panel 110, the printed circuit board 117 is connected through a connecting member 116, such as a flexible circuit board or a tape carrier package (TCP), in the modularization process. The side surface of the support main 130 or the cover bottom 150 is properly folded to be in close contact.

When the thin film transistor selected for each gate line is turned on by the on / off signal of the gate driver circuit, the liquid crystal panel 110 transmits the signal voltage of the data driver circuit to the corresponding pixel electrode through the data line. The arrangement direction of the liquid crystal molecules is changed by the electric field between the pixel electrode and the common electrode, indicating a difference in transmittance.

In addition, the backlight unit 120 is provided to supply light to the rear surface of the liquid crystal panel 110 so that the difference in transmittance indicated by the liquid crystal panel 110 is expressed to the outside.

The backlight unit 120 includes an LED assembly 129, a white or silver reflecting plate 125, a light guide plate 123 seated on the reflecting plate 125, and an optical sheet 121 interposed thereon. .

The LED assembly 129 is positioned at one side of the light guide plate 123 to face the light incident surface of the light guide plate 123, and the plurality of LEDs 129a and the plurality of LEDs 129a are mounted at a predetermined interval apart from each other. ).

The light guide plate 123 into which the light emitted from the plurality of LEDs 129a of the LED assembly 129 is incident enters the light guide plate 123 while the light incident from the LED 129a travels in the light guide plate 123 by a plurality of total reflections. Spread evenly over a wide area of) provides a surface light source to the liquid crystal panel (110).

The light guide plate 123 may include a pattern of a specific pattern on the back surface to supply a uniform surface light source.

Here, the pattern may be configured in various ways, such as an elliptical pattern, a polygon pattern, a hologram pattern, and the like to guide the light incident into the light guide plate 123. The pattern is formed on the lower surface of the light guide plate 123 by a printing method or an injection method.

The reflection plate 125 is disposed on the back surface of the light guide plate 123 and reflects light passing through the back surface of the light guide plate 123 toward the liquid crystal panel 110 to improve the brightness of light.

The optical sheet 121 on the light guide plate 123 includes a diffusion sheet 124 and a composite light collecting sheet 200, and diffuses and condenses the light passing through the light guide plate 123 to be more uniform with the liquid crystal panel 110. Let the surface light source enter.

Here, the composite light collecting sheet 200 may be formed by combining at least two light collecting sheets integrally, thereby realizing high brightness and reducing the overall thickness of the liquid crystal display. We will discuss this in more detail later.

The liquid crystal panel 110 and the backlight unit 120 are modularized through the top cover 140, the support main 130, and the cover bottom 150. The top cover 140 is the top and side surfaces of the liquid crystal panel 110. A rectangular frame having a cross section bent in a shape of “a” so as to cover an edge thereof is configured to open an entire surface of the top cover 140 to display an image implemented in the liquid crystal panel 110.

In addition, the cover bottom 150, which is the basis for assembling the entire apparatus of the liquid crystal display device 100 by mounting the liquid crystal panel 110 and the backlight unit 120, is formed to surround the back and side surfaces of the backlight unit 120.

The support main body 130 having a rectangular frame shape and resting on the cover bottom 150 and covering the edges of the liquid crystal panel 110 and the backlight unit 120 includes a top cover 140, a cover bottom 150, .

The cover main body 130 may be referred to as a guide panel or a main support or a mold frame. The cover main body 130 may be referred to as a bottom cover or a bottom cover, I will.

In the liquid crystal display device according to the embodiment of the present invention described above, the overall thickness is reduced compared to the conventional liquid crystal display device, which has a thickness of the backlight unit 120 having the greatest effect on the thickness of the liquid crystal display device. Because it was reduced.

That is, the conventional backlight unit 20 of FIG. 1 includes a plurality of optical sheets such as a diffusion sheet and a light collecting sheet on the light guide plate 23 of FIG. 1, and a plurality of light collecting sheets are overlapped to realize higher brightness. However, in the present invention, since only two optical sheets of the diffusion sheet 124 and the composite light collecting sheet 200 are positioned on the light guide plate 123, the thickness of the backlight unit 120 is reduced as compared with the conventional art.

In particular, since the composite light collecting sheet 200 is formed in a form in which two light collecting sheets are integrally bonded to each other, the overall thickness of the optical sheets 121 may be reduced as compared with applying a plurality of light collecting sheets, respectively, while achieving high brightness. .

Accordingly, the liquid crystal display device of the present invention can realize a light weight and a thin shape, and many components of the backlight unit 120 have increased the working process time in the modularization process of the liquid crystal display device, thereby reducing the efficiency of the process. Compared to this, the working time can be shortened, improving the efficiency of the process.

That is, the present invention can provide an efficient backlight unit 120 with excellent performance.

First Embodiment

3 is a schematic cross-sectional view of a composite light collecting sheet according to a first embodiment of the present invention.

As shown, the composite light collecting sheet 200 is largely composed of a first light collecting part 210 and a second light collecting part 220. The first light collecting part 210 is formed of a first support layer 211 and a first light. The first lens layer 213 for condensing light from the upper surface of the support layer 211 and the first diffusion layer 215 for diffusing light are formed on the lower surface of the first support layer 211.

In addition, the second condenser 220 positioned below the first condenser 210 may include a second support layer 221 and a second lens layer for condensing light from an upper surface of the second support layer 221. 223).

Here, in more detail with respect to these layers, the first and second support layers 211 and 221 of the first and second light concentrators 210 and 220 are polycarbonate-based, poly that can transmit light. Poly sulfone, poly acrylate, poly styrene, poly vinyl chloride, poly vinyl alcohol, poly norbornene It consists of a series, a polyester (polyester) series, etc.

Here, the first support layer 211 serves as a base for supporting the entire condensing sheet 200, and the second support layer 221 supports only the second lens layer 223 of the second condenser 220. Since the thickness d2 of the second support layer 221 is formed to be thinner than the thickness d1 of the first support layer 211, the overall thickness of the composite light collecting sheet 200 may be reduced.

The first and second lens layers 213 and 223 formed on the first and second support layers 211 and 221, respectively, are made of a transparent acrylic resin, and the length of the composite light collecting sheet 200 is increased. A plurality of first and second prism acids 217 and 227 in the form of a band-like adjoining direction are repeated so as to protrude from the first and second support layers 211 and 221 in a row. .

Due to the first and second prism acids 217 and 227, the composite light condensing sheet 200 condenses light to a liquid crystal panel (110 of FIG. 2) positioned on the upper portion of the composite light condensing sheet 200. Has a synergistic effect.

At this time, the composite light collecting sheet 200 according to the first embodiment of the present invention is characterized in that the second prism acid 227 of the second lens layer 223 of the second light collecting unit 220 has adhesive properties. .

That is, the first condenser 210 and the second condenser 220 are integrally bonded to each other through the adhesive property of the second lens layer 223 of the second condenser 220.

The first diffusion layer 215 formed below the first support layer 211 of the first light collecting part 210, that is, the lower surface opposite to the first support layer 211 on which the first lens layer 213 is formed, Light diffusion components such as beads 215a may be included, or fine patterns may be formed on the bottom surface of the first diffusion layer 215 without including the beads 215a.

Through this, the first diffusion layer 215 diffuses the light by refracting and scattering the incident light, and serves to emit the non-uniform light passed through the light guide plate 123 of FIG. 2 as uniform light.

At this time, the bead 215a is configured to be included in the binder resin, the bead 215a has a feature that can prevent the light is partially concentrated by dispersing the light incident on the first diffusion layer 215.

As the binder resin, an acrylic resin, a urethane resin, an epoxy resin, a vinyl resin, a polyester resin, a polyamide resin, or the like can be used as the binder resin because of high transparency and excellent light transmittance and easy viscosity control.

In addition, the first diffusion layer 215 that does not include the beads 215a has a feature that can adjust the light scattering angle according to the shape of the fine pattern (not shown), the fine pattern (not shown) is an elliptical pattern (elliptical) pattern, polygon pattern, etc., and the hologram pattern is used to refract the light incident by the interference pattern in an asymmetrical direction. Can spread to

At this time, the thickness of the first diffusion layer 215 is preferably formed to 1000 ~ 2000㎛.

As a result, light is dispersed through the first diffusion layer 215 to prevent the light from being partially concentrated.

Although not shown, a second diffusion layer (not shown) may be formed on the lower surface of the second support layer 221, but the second diffusion layer (not shown) formed on the lower surface of the second support layer 221 may be formed. At the same time to diffuse the light serves to improve the problem caused by the adhesion with the diffusion sheet (124 of FIG. 2) located at the bottom of the composite light collecting sheet (200).

Therefore, the diffusion sheet (124 of FIG. 2) of the composite light collecting sheet 200 may be prevented from appearance defects due to wet-out phenomenon that may be generated by being in close contact with each other and moiré patterns that may be generated on the display screen. have.

As described above, the liquid crystal display of the present invention includes the composite light collecting sheet 200 on the optical sheet 121 (see FIG. 2), thereby reducing the thickness of the backlight unit (120 of FIG. 2) compared with the conventional light collecting sheet. As the number of components decreases, the efficiency of the modularization process of the liquid crystal display device may be improved.

- Second Embodiment -

4 is a cross-sectional view schematically showing a composite light collecting sheet according to a second embodiment of the present invention.

Here, in order to avoid overlapping description, the same reference numerals are assigned to the same parts which play the same role as the above-described first embodiment, and only the characteristic contents to be described in the second embodiment will be described.

As illustrated, the composite light collecting sheet 200 according to the second embodiment of the present invention is formed by overlapping the second prism acid 227 of the second lens layer 223 of the second light collecting part 220 with each other. It is characterized by.

Looking at this in more detail, the composite light collecting sheet 200 is largely composed of the first condenser 210 and the second condenser 220, the first condenser 210 is the first support layer 211, The first lens layer 213 for condensing light from the upper surface of the first support layer 211 and the first diffusion layer 215 for diffusing light are formed on the lower surface of the first support layer 211.

In addition, the second condenser 220 positioned below the first condenser 210 may include a second support layer 221 and a second lens layer for condensing light from an upper surface of the second support layer 221. 223).

The first and second lens layers 213 and 223 formed on the first and second support layers 211 and 221, respectively, are made of a transparent acrylic resin, and the length of the composite light collecting sheet 200 is increased. A plurality of first and second prism acids 217 and 227 in the form of a band-like adjoining direction are repeated so as to protrude from the first and second support layers 211 and 221 in a row. .

These first and second prism mountains 217, 227 have first and second inclined surfaces 217a, 217b, 227a, 227b that are inclined at an angle from the edge.

Due to the first and second prism acids 217 and 227, the composite light condensing sheet 200 condenses light to a liquid crystal panel (110 of FIG. 2) positioned on the upper portion of the composite light condensing sheet 200. Has a synergistic effect.

At this time, the angle (theta) of the edge which forms the vertex of the 1st and 2nd prism mountains 217, 227 is 80-90 degrees.

Here, the refractive indexes of the first and second lens layers 213 and 223 of the composite light collecting sheet 200 are preferably 1.57 to 1.58.

The first diffusion layer 215 formed below the first support layer 211 of the first light collecting part 210, that is, the lower surface opposite to the first support layer 211 on which the first lens layer 213 is formed, Light diffusion components such as beads 215a may be included, or fine patterns may be formed on the lower surface of the first diffusion layer 215 without including the beads 215a.

At this time, the thickness of the first diffusion layer 215 is preferably formed to 1000 ~ 2000㎛.

Although not shown, a second diffusion layer (not shown) may be formed on the lower surface of the second support layer 221, but the second diffusion layer (not shown) formed on the lower surface of the second support layer 221 may be formed. At the same time, it diffuses light and serves to improve adhesion to the diffusion sheet (124 of FIG. 2) positioned below the composite light collecting sheet 200.

In this case, in the composite light collecting sheet 200 according to the second embodiment of the present invention, the second prism acid 227 of the second lens layer 223 of the second light collecting part 220 has an adhesive property.

Therefore, the first condenser 210 and the second condenser 220 are integrally bonded to each other through the adhesive property of the second lens layer 223 of the second condenser 220.

In addition, the second lens layer 223 according to the second exemplary embodiment of the present invention may be defined by being divided into a plurality of prism acid portions A in which a plurality of second prism acids 227 are formed to overlap each other.

That is, the prism acid portion is formed by the second prism acid 227 of the second to 2-3 prism acid (1-227, 2-227, 3-227) one prism acid portion (A), wherein The second inclined surface of the 2-1 prism and the third inclined surface of the 2-2 prism are formed to overlap each other, and the fourth inclined surface of the 2-2 prism and the fifth inclined surface of the 3-2 prism These are formed to overlap each other.

Therefore, when the length of the first inclined surface 227a of the 2-1 prism mountain 1-227 is 1, the prism mountain portion A forms an edge with the first inclined surface 227a to form one second-1 prism. The exposed length of the second inclined surface 227b constituting the acid 1-227 is 0.5, and the length of the 2-2 prism acid 2-227 adjacent to the 2-1 prism mountain 1-227 is determined. The exposed length of the third inclined surface 227c is 0.5.

The second inclined surface 227d of the second-2 prism acid 2-227 is formed to expose a length of 0.5, and the second 2-3 prism acid adjacent to the second-2 prism acid 2-227 is exposed. The length of the fifth inclined surface 227e of (3-227) is also exposed so that 0.5 is exposed so that the length of the fifth inclined surface 227e overlaps with the fourth inclined surface 227d of the second-2 prism mountain (2-227). Is formed to have a length of 1.

That is, the 2-1 to 2-3 prism acids (1-227, 2-227, 3-227) are located at the same position where the heights of the vertices of the corners projecting from the second support layer 221 are the same. In the state, the 2-2 prism acid (2-227) located at the center of the height h1 of the 2-1 and 2-3 prism acids (1-227, 3-227) substantially exposed and formed. Height h2 is formed to be low.

Accordingly, the prism acid portion A has a shape in which a plurality of second prism acids 1-227, 2-227, and 3-227 overlap each other, and thus have a substantially crown shape having a plurality of corners.

At this time, the inclined surfaces 227a and 227b of the 2-1 prism mountain 1-227 and the inclined surfaces 227e and 227f of the 2-3 prism acid 3-227 may be in contact with each other and are formed at a predetermined interval. The lengths of the inclined surfaces 227b, 227c, 227d, and 227e other than the inclined surfaces 227a and 227f formed at the outermost portion of the prism mountain portion A may be the same or may have different lengths.

In the composite light collecting sheet 200 according to the second embodiment of the present invention, the second lens layer 223 of the second light collecting part 220 is arranged such that a plurality of prism acid parts A are arranged side by side.

Therefore, the number of second prism acids 1-227, 2-227, and 3-227 of the second lens layer 223 of the second condenser 220 is equal to the first lens layer of the first condenser 210. The number of first prism mountains 217 of 213 is greater than that of the same area.

As a result, the contact area between the first diffusion layer 215 of the first condenser 210 and the second lens layer 223 of the second condenser 220 is enlarged, whereby the first condenser 210 and the first condenser 210 are formed. The bonding force of the two light collecting parts 220 is improved.

Therefore, the composite light collecting sheet 200 according to the second embodiment of the present invention can reduce the thickness of the backlight unit (120 of FIG. 1) as compared with the conventional light condensing sheet having a plurality of light collecting sheets. The efficiency of the modularization process of the display device can be improved.

In addition, the first condensing unit 210 may be formed by overlapping the second prism acids 1-227, 2-227, and 3-227 of the second lens layer 223 of the second condenser 220. ) And the bonding force of the second light collecting part 220 may be improved.

Third embodiment

5 is a cross-sectional view schematically showing a composite light collecting sheet according to a third embodiment of the present invention.

Here, in order to avoid duplicate description, the same reference numerals are assigned to the same parts that play the same role as the above-described descriptions of the first and second embodiments, and only the characteristic contents to be described in the third embodiment will be described. would.

As shown in the drawing, the composite light collecting sheet 200 according to the third embodiment of the present invention includes a first light collecting part 210 and a second light collecting part 220. The first support layer 211, the first lens layer 213 for condensing light from the upper surface of the first support layer 211, and the first diffusion layer 215 for diffusing light are provided on the lower surface of the first support layer 211. )

In addition, the second condenser 220 positioned below the first condenser 210 may include a second support layer 221 and a second lens layer for condensing light from an upper surface of the second support layer 221. 223).

Here, in more detail with respect to these layers, the first and second support layers 211 and 221 of the first and second light concentrators 210 and 220 are polycarbonate-based, poly that can transmit light. Poly sulfone, poly acrylate, poly styrene, poly vinyl chloride, poly vinyl alcohol, poly norbornene It consists of a series, a polyester (polyester) series, etc.

Here, the first support layer 211 serves as a base for supporting the entire condensing sheet 200, and the second support layer 221 supports only the second lens layer 223 of the second condenser 220. Since the thickness d2 of the second support layer 221 is formed to be thinner than the thickness d1 of the first support layer 211, the overall thickness of the composite light collecting sheet 200 may be reduced.

The first and second lens layers 213 and 223 formed on the first and second support layers 211 and 221, respectively, are made of a transparent acrylic resin, and the length of the composite light collecting sheet 200 is increased. A plurality of first and second prism acids 217 and 227 in the form of a band-like adjoining direction are repeated so as to protrude from the first and second support layers 211 and 221 in a row. .

These first and second prism mountains 217, 227 have first and second inclined surfaces 217a, 217b, 227a, 227b that are inclined at an angle from the edge.

Due to the first and second prism acids 217 and 227, the composite light condensing sheet 200 condenses light to a liquid crystal panel (110 of FIG. 2) positioned on the upper portion of the composite light condensing sheet 200. Has a synergistic effect.

At this time, the angle (theta) of the edge which forms the vertex of the 1st and 2nd prism mountains 217, 227 is 80-90 degrees.

That is, the first and second inclined surfaces 217a, 217b, 227a, and 227b of the first and second prism mountains 217 and 227 are inclined about 45 to 50 degrees from the first and second support layers 211 and 221, respectively. It is formed so that the edges formed by the first and second inclined surfaces (217a, 217b, 227a, 227b) is 80 to 90 degrees.

Here, the refractive indexes of the first and second lens layers 213 and 223 of the composite light collecting sheet 200 are preferably 1.57 to 1.58.

This is because the luminance of the composite light collecting sheet 200 is reduced by the first diffusion layer 215, so that the refractive indexes of the first and second lens layers 213 and 223 have a refractive index of 1.57 to 1.58, so that the composite light collecting sheet 200 may be reduced. The light passing through the light is more concentrated, which is to compensate for the luminance lowered by the first diffusion layer 215 and to further increase the luminance.

At this time, the second prism acid 227 of the second lens layer 223 of the second condenser 220 has an adhesive property, so that the first condenser 210 and the second condenser 220 are second condensed. Through the adhesive property of the second lens layer 223 of the light unit 220 is formed to be integrally bonded to each other.

In addition, the first diffusion layer 215 formed on the lower surface of the first support layer 211 of the first light collecting part 210 may include light diffusion components such as beads 215a, or may form the beads 215a. It may be configured by forming a fine pattern on the lower surface of the first diffusion layer 215 without including.

Through this, the first diffusion layer 215 diffuses the light by refracting and scattering the incident light, and serves to emit the non-uniform light passed through the light guide plate 123 of FIG. 2 as uniform light.

At this time, the bead 215a is configured to be included in the binder resin, the bead 215a has a feature that can prevent the light is partially concentrated by dispersing the light incident to the first diffusion layer 215.

As the binder resin, an acrylic resin, a urethane resin, an epoxy resin, a vinyl resin, a polyester resin, a polyamide resin, or the like can be used as the binder resin because of high transparency and excellent light transmittance and easy viscosity control.

In addition, the first diffusion layer 215 that does not include the beads 215a has a feature that can adjust the light scattering angle according to the shape of the fine pattern (not shown), the fine pattern (not shown) is an elliptical pattern (elliptical) pattern, polygon pattern, etc., and the hologram pattern is used to refract the light incident by the interference pattern in an asymmetrical direction. Can spread to

At this time, the thickness of the first diffusion layer 215 is preferably formed to 1000 ~ 2000㎛.

As a result, light is dispersed through the first diffusion layer 215 to prevent the light from being partially concentrated.

Although not shown, a second diffusion layer (not shown) may be formed on the lower surface of the second support layer 221, but the second diffusion layer (not shown) formed on the lower surface of the second support layer 221 may be formed. At the same time to diffuse the light serves to improve the problem caused by the adhesion with the diffusion sheet (124 of FIG. 2) located at the bottom of the composite light collecting sheet (200).

Therefore, the diffusion sheet (124 of FIG. 2) of the composite light collecting sheet 200 may be prevented from appearance defects due to wet-out phenomenon that may be generated by being in close contact with each other and moiré patterns that may be generated on the display screen. have.

As described above, the liquid crystal display of the present invention includes a composite light collecting sheet 200, thereby reducing the thickness of the backlight unit (120 of FIG. 2) compared to the conventional light collecting sheet, and reducing components. Accordingly, the efficiency of the modularization process of the liquid crystal display device can be improved.

Particularly, in the composite light collecting sheet 200 according to the third embodiment of the present invention, the heights h3 and h4 of the second prism mountains 227 adjacent to each other of the second lens layer 223 of the second light collecting unit 220 are shown. That is, the heights h3 and h4 of the second prism acid 227 protruding from the second support layer 221 may be formed differently.

That is, the plurality of second-first prism 1-227 is formed to have a first height h3, and the plurality of second-second prism 2-227 has a second height lower than the first height h3. It is formed to have (h4).

This is because the second condenser 220 of the second condenser 220 is integrally bonded to each other through the adhesive property of the second lens layer 223. This is for the angle θ of the corner formed by the first and second inclined surfaces 227a and 227b of 227 to have an optimal shape.

In general, the second prism acid 227 serves to change the direction of the light by refracting and reflecting the light. The characteristics of the second prism acid 227 are the first and the second characteristics of the second prism acid 227. It is determined by the angle θ of the corner formed by the two inclined surfaces 227a and 227b.

In other words, when the angle θ of the corner of the second prism acid 227 forms 90 °, the light collecting performance of the light of the second prism acid 227 is most efficient.

However, in the case of the composite light collecting sheet 200 in which the first and second light collecting parts 210 and 220 are integrally bonded to each other like the third embodiment of the present invention, the second light collecting part 220 of the lower As the second prism acid 227 of the second lens layer 223 is in contact with the first diffusion layer 215 of the first condenser 210, the second prism acid 227 of the second condenser 220 The angle θ of the corner of the does not reach 90 °.

Accordingly, in the composite light collecting sheet 200 according to the second embodiment of the present invention, the heights h3 and h4 of the second prism acid 227 of the second lens layer 223 are regularly different from each other, so that the second light collecting part 220 is formed. The second prism acid 227 whose angle θ of the corner of the second prism acid 227 of the s) does not form 90 ° can be formed to a minimum, thereby further improving the light condensing performance of the second light collecting part 220. You can.

Therefore, the luminance is improved as compared with the conventional art.

At this time, among the second prism mountains 227 of the second light collecting part 220, the number of the 2-1 prism acids 1-227 contacting the rear surface of the first diffusion layer 215 of the first light collecting part 210 is large. It is preferable that at least 30% of the second prism acid 227 form the 2-1 prism acid (1-227), thereby preventing the adhesive force of the first and second condensing parts 210 and 220 from being lowered. Do.

At this time, the heights h3 and h4 of the plurality of second prism mountains 227 of the second lens layer 223 may have an angle θ of the corner formed by the inclined surfaces 227a and 227b of the second prism mountains 227. It is possible to design freely within the limit of 90 °, and the height h4 of the second-second prism acid 2-227 of the second lens layer 223 is bonded to the first condenser 210. It is preferably in the range of 10 to 90% of the height h3 of the -1 prism acid (1-227).

In addition, the 2-1 and 2-2 prism acids (1-227, 2-227) according to the heights (h3, h4) of the 2-1 and 2-2 prism acids (1-227, 2-227). ), That is, the intervals P1 and P2 between the first and second inclined surfaces 227a and 227b may be formed regularly differently.

Here, the intervals P1 and P2 of the second prism acid 227 are formed at the edges formed by the first and second inclined surfaces 227a and 227b of the second prism acid 227 within a range of not exceeding 40 to 90 μm. It is preferable to form differently regularly so that angle (theta) may make 90 degrees.

Accordingly, in the composite light collecting sheet 200 according to the third embodiment of the present invention, the heights h3 and h4 of the second prism acid 227 of the second light collecting part 220 are regularly different from each other, thereby forming the second light collecting device. The light collecting performance of the lighter 220 may be further improved.

In addition, the composite light collecting sheet 200 according to the third embodiment of the present invention can minimize light loss due to side lobes, thereby improving light efficiency and viewing angle characteristics.

That is, since the first and second condensing parts 210 and 220 are bonded to each other by the second prism acid 227 of the second condensing part 220, the first and second condensing parts 210 are formed. , The light incident to the second condenser 220 is incident as it is to the first condenser 210 having the same refractive index as the second condenser 220.

At this time, the light incident on the condensing region of the second condenser 220 is condensed in the direction toward the liquid crystal panel 110 of FIG. 2, as it passes through the first condenser 210, as shown in FIG. 6A. The light incident to the line perpendicular to the lower surface of the second light concentrator 220 is inclined by about 5 degrees, and the first light concentrator 210 is also incident on the light perpendicular to the line perpendicular to the lower surface.

Therefore, light loss due to side lobes is accompanied, resulting in a decrease in light efficiency and a decrease in viewing angle characteristics.

Through this, a spectrum mura or a hot band is generated, and also the light collecting performance of the composite light collecting sheet 200 is reduced.

On the contrary, in the composite light collecting sheet 200 according to the third embodiment of the present invention, as illustrated in FIG. 6B, the heights h3 and h4 of the second prism mountains 227 of the second light collecting part 220 are mutually different. By forming differently, the second prism acid 227 does not come into contact with the first condensing part 210, so that the incident light is inclined by about 5 ° with a line perpendicular to the lower surface of the second condensing part 220. The total reflectance toward the first condenser 210 is caused by an air gap (refractive index 1.0) having a refractive index different from that of the second condenser 220.

Through this, it is possible to minimize the light loss caused by the side lobe, it is possible to prevent the occurrence of spectral mura (hot band) or (hot band).

At this time, the front luminance and the side lobe can be controlled by adjusting the mixing ratio of the 2-1 prism acid (1-227) and the 2-2 prism acid (2-227).

The manufacturing method of the composite light collecting sheet of the third embodiment of the present invention is as follows.

7 is a schematic view of a composite light collecting sheet manufacturing apparatus according to a third embodiment of the present invention.

The composite light collecting sheet manufacturing apparatus 300 according to the third embodiment of the present invention includes a film introduction part 310, a resin dropping part 320, a pattern forming part 330, an adhesive part 340, a hardening part 350, and a carrying out part. The second support layer 221, which is configured to include the portion 360 and is provided to the film introduction portion 310, moves to the carry-out portion 360 by driving the plurality of rollers 371, 373, and 375.

At this time, in the film introduction part 310, the second unwinding roll in which only the first unwinding roll 371 and the second support layer 221 on which the first condenser 210 on which the first prism acid 217 is formed are wound are wound. 373 is provided.

Here, the first condenser 210 wound around the first unwinding roll 371 may include a first lens layer (FIG. 1) formed of a plurality of first prism acids 217 on the first support layer (211 of FIG. 5). 213 is formed, and a first diffusion layer (215 in FIG. 5) is formed on a lower surface of the first support layer (211 in FIG. 5) and the second support layer 221 wound on the second unwinding roll 373. ) Is made of polymethylmethacrylate (PMMA), polyethylene terephthalate (PET) and the like.

As such, the second support layer 221 wound around the second unwinding roll 373 among the first and second unwinding rolls 371 and 373 provided in the film introduction part 310 is formed through the film introduction part 310. It moves to the resin dropping part 320, the resin 321 is dripped on the 1st support layer 221, and the resin layer 323 is formed on the 1st support layer 221. FIG.

At this time, the resin layer 323 dropped on the first support layer 221 has an adhesive characteristic.

Next, the first support layer 221 on which the resin layer 323 is formed is moved to the pattern forming unit 330, whereby a pattern in which an acid and a valley are alternately formed on the surface of the resin layer 323 on the first support layer 221 is formed. The mold roller 331 is pressed to form a pattern 227 in which an acid and a valley are alternately formed on a surface thereof.

Through this, the second condenser 220 is formed.

At this time, the pattern 227 is made of a prism shape having a first and second inclined surfaces (227a, 227b in FIG. 5) inclined at a predetermined angle from the corner, and the height of the prism pattern 227 (FIG. 5). H3, h4) are formed differently.

Thereafter, the second condenser 220 having the pattern 227 formed thereon and the first condenser 210 wound around the first unwinding roll 371 are moved to the adhesive part 340 to form the first condenser 210. And each other by the guide rollers 341 which press on the upper and lower portions of the second light collecting part 220.

In this case, since the pattern 227 of the second light collecting part 220 has an adhesive property, the first and second light collecting parts 210 and 220 are bonded to each other.

Finally, the film to which the first and second light collecting parts 210 and 220 are bonded is cured by irradiating UV light through the ultraviolet lamp 351 in the curing part 350, and then wound on the rewinding roll 375. .

The film wound on the rewinding roll 375 is cut according to the model to be used, thereby completing the composite light collecting sheet 200 that is applied to the modularization process of the liquid crystal display device.

Meanwhile, the backlight unit (120 of FIG. 2) having the above-described structure is generally called a side light method, and a plurality of LEDs (129a of FIG. 2) are mounted on the PCB (129b of FIG. 2) according to the purpose. Can be arranged in multiple layers. In addition, it is also possible to include a plurality of sets of the LED assembly (129 of FIG. 2) to correspond to each other along both side edge portions of the cover bottom (150 of FIG. 2) facing each other.

In addition, in the above description, for convenience, the side light method is used as a liquid crystal display device in which the composite light collecting sheet 200 according to the present invention may be used, but this may be applied to a direct type method, in which case the light guide plate (123 of FIG. ), A plurality of LED assemblies (129 of FIG. 2) are arranged side by side on the reflecting plate (125 of FIG. 2), and the composite light collecting sheet 200 according to the embodiment of the present invention may be disposed thereon. have.

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

200: composite light collecting sheet
210: first light collecting part 211: first support layer, 213: first lens layer, 215: first diffusion layer 215a: bead, 217: prism acid 217a, 217b: first and second inclined surfaces)
220: second condenser 221: second support layer, 223: second lens layer, 227: prism acid (227a, 227b: first and second inclined surfaces)

Claims (17)

A liquid crystal panel;
A light source positioned under the liquid crystal panel;
A first collector including a first lens layer on the light source, the first lens layer having a plurality of first prism acids formed on one surface facing the liquid crystal panel, and a first diffusion layer on the other surface opposite to one surface on which the first prismatic acids are formed; A second light collecting portion including a light portion and a second lens layer formed with a plurality of second prism acids having a first height and attached to the first diffusion layer and a plurality of third prism acids having a second height lower than the first height Composite condensing sheet comprising a
And a vertex of an edge of the second prism acid attached to the first diffusion layer.
A liquid crystal panel;
A light source positioned under the liquid crystal panel;
A first collector including a first lens layer on the light source, the first lens layer having a plurality of first prism acids formed on one surface facing the liquid crystal panel, and a first diffusion layer on the other surface opposite to one surface on which the first prismatic acids are formed; A composite light collecting sheet including a light collecting unit and a second light collecting unit including a second lens layer having a plurality of second prism acids formed to overlap the first diffusion layer and overlap each other.
And a vertex of an edge of the second prism acid attached to the first diffusion layer.
The method according to any one of claims 1 and 2,
The second lens layer has an adhesive property.
The method of claim 1,
The plurality of first to third prism acids are formed of first and second inclined surfaces that form an edge of 80 to 90 °, respectively, and the refractive index of the first and second lens layers is 1.57 to 1.58.
5. The method of claim 4,
The first and second light collecting parts include first and second support layers each made of PMMA (polymethylmethacrylate), polyethylene terephthalate (PET), and the like, and the first lens layer protrudes from the first support layer. And a first diffusion layer formed on a rear surface of the first support layer, and the second lens layer protrudes from the second support layer.
The method of claim 1,
And the number of the plurality of second prism acids is 30% of the plurality of first and second prism acids of the second lens layer.
The method of claim 1,
The height of the plurality of third prism acid ranges from 10 to 90% of the height of the plurality of second prism acid.
The method of claim 7, wherein
The interval between the plurality of second prism acid and the plurality of third prism acid is 40 ~ 90㎛ the liquid crystal display device.
The method of claim 3, wherein
And a second diffusion layer on a rear surface of the second support layer.
3. The method of claim 2,
The plurality of first and second prism acids are formed of first and second inclined planes forming an edge of 80 to 90 °, respectively, and the refractive index of the first and second lens layers is 1.57 to 1.58.
11. The method of claim 10,
The first and second light collecting parts include first and second support layers each made of PMMA (polymethylmethacrylate), polyethylene terephthalate (PET), and the like, and the first lens layer protrudes from the first support layer. And a first diffusion layer formed on a rear surface of the first support layer, and the second lens layer protrudes from the second support layer.
11. The method of claim 10,
And the second lens layer is divided into a plurality of prism acid portions, and the plurality of prism acid portions are formed by overlapping inclined surfaces of the plurality of second prism acids, respectively.
13. The method of claim 12,
The second prism acid is a liquid crystal display device wherein the vertices of the corner protruding from the second support layer is located at the same height.
The method of claim 13,
The first and second inclined surfaces of the plurality of second prism acids have the same length or have different lengths.
The method according to any one of claims 1 and 2,
A reflective plate is positioned below the composite light collecting sheet, and a light guide plate is formed on the reflective plate, and the light source is arranged on one side or both sides of the light guide plate.
A first lens layer formed on one surface of the first support layer, the first lens layer protruding to be arranged adjacent to each other on the first support layer, and a first formed on the rear surface of the first support layer. A first light collecting part including a first diffusion layer;
A second support layer, a plurality of second prism acids formed on one surface of the second support layer, attached to the first diffusion layer, and having a first height, and a plurality of third prisms having a second height lower than the first height; A second light collecting part including a second lens layer having an acid formed therein;
And a vertex of an edge of the second prism acid attached to the first diffusion layer.
A first lens layer formed on one surface of the first support layer, the first lens layer protruding to be arranged adjacent to each other on the first support layer, and a first formed on the rear surface of the first support layer. A first light collecting part including a first diffusion layer;
A second light collecting part including a second support layer and a second lens layer formed on one surface of the second support layer and attached to the first diffusion layer and having a plurality of second prism acids formed to overlap each other;
And a vertex of an edge of the second prism acid attached to the first diffusion layer.

Images