WO2014092507A1

WO2014092507A1 - Multi-light guide sheet and liquid crystal display device including same

Info

Publication number: WO2014092507A1
Application number: PCT/KR2013/011604
Authority: WO
Inventors: 최미정; 박경곤; 김영민; 나연주
Original assignee: 제일모직 주식회사
Priority date: 2012-12-14
Filing date: 2013-12-13
Publication date: 2014-06-19

Abstract

The present invention relates to a multi-light guide sheet including: a first optical sheet having an adhesive layer formed on one side thereof; and a second optical sheet formed beneath the adhesive layer and having an optical pattern formed on one side thereof, wherein the optical pattern includes a plurality of first prisms and a plurality of second prisms with a height lower than that of the first prism, the apex of the first prisms is embedded in the adhesive layer, and the apex of the second prisms is embedded in or contacts the adhesive layer, and to a liquid crystal display device including the same.

Description

【Specification】

[Name of invention]

Composite optical sheet and liquid crystal display including the same

The present invention relates to a composite optical sheet and a liquid crystal display including the same. Background Art

Liquid crystal displays are one of the most widely used flat panel displays at present. The liquid crystal display has a structure in which a liquid crystal layer is sealed between the TFT array substrate and the color filter substrate. An electric field is applied to the electrodes existing on the array substrate and the color filter substrate, and the arrangement of the liquid crystal molecules of the liquid crystal layer enclosed therebetween is changed to display an image by using the same. Since the liquid crystal display does not emit light by itself, a backlight unit is required. The backlight unit may include a light source such as a light emitting diode or a fluorescent lamp, a light guide plate, a prism sheet, a diffusion sheet, a protective sheet, and the like.

For recent thinning, the backlight unit includes a composite optical sheet. The composite optical sheet has a structure of adhering an upper optical sheet and a lower optical sheet with an adhesive layer. However, due to the adhesive layer, the luminance may be lowered compared to when the two optical sheets are simply laminated. If the adhesive area is not sufficient, the adhesive force may be lowered. In addition, moiré may occur when a plurality of optical patterns are formed. In this regard, Korean Patent No. 10-1155876 discloses a composite optical sheet, a manufacturing method thereof, a lighting device and a display device including the same.

[Detailed Description of the Invention]

[Technical problem]

The problem to be solved by the present invention is to provide a composite optical sheet excellent in brightness and adhesion.

Another object of the present invention is to provide a composite optical sheet capable of avoiding moiré generation. Another object of the present invention is to provide a liquid crystal display device including the composite optical sheet.

Technical Solution

Composite optical sheet according to an aspect of the present invention comprises a first optical sheet comprising an adhesive layer on one surface; And a second optical sheet formed under the adhesive layer and including an optical pattern on one surface thereof, wherein the optical pattern includes a plurality of first prisms and a plurality of second prisms having a lower height than the first prism, A vertex of the first prism penetrates the adhesive layer and exists inside the adhesive layer, and a vertex of the second prism penetrates the adhesive layer and may exist inside or in contact with the adhesive layer.

According to another aspect of the present invention, a liquid crystal display device includes: a light source unit; A light guide plate formed on the light source unit; The composite optical sheet formed on the light guide plate; And a liquid crystal display panel formed on the composite optical sheet. Advantageous Effects

The present invention provides a composite optical sheet having excellent brightness and adhesion.

The present invention provides a composite optical sheet capable of avoiding moiré generation. The present invention provides a liquid crystal display device including the composite optical sheet. [Brief Description of Drawings]

1 is a bo

A perspective view of a composite optical sheet according to the invention.

tr 2 is a cross-sectional view of a composite optical sheet according to an embodiment of the present invention.

3 is a cross-sectional view of a composite optical sheet according to another embodiment of the present invention.

tr 4 is a cross-sectional view of a composite optical sheet according to another embodiment of the present invention.

5 is a perspective view of a composite optical sheet according to another embodiment of the present invention. FIG. 6 is a cross-sectional view of a composite optical sheet according to another embodiment of the present invention. FIG. 7 is a compound optical according to another embodiment of the present invention. 8 is a cross-sectional view of a composite optical sheet according to another embodiment of the beam invention tr 9 is a cross-sectional view of a composite optical sheet according to another embodiment of the beam invention FIG. 10 is a further embodiment of the present invention Sectional view of a composite optical sheet according to. 11 is a perspective view of a composite optical sheet according to another embodiment of the present invention. 12 is a cross-sectional view of a liquid crystal display according to an exemplary embodiment of the present invention. [Best form for implementation of the invention]

Hereinafter, with reference to the accompanying drawings, it will be described in detail the embodiments of the present application. However, the technology disclosed in the present application is not limited to the embodiments described herein and may be embodied in other forms. However, the embodiments introduced herein are provided to enable the disclosed contents to be thorough and complete, and to fully convey the spirit of the present application to those skilled in the art. In the drawings, the width, thickness, and the like of the components are enlarged in order to clearly express the components of each device. In addition, although only a part of the components are shown for convenience of description, those skilled in the art will be able to easily understand the rest of the components. When described in the drawings as a whole, it is described at the observer's point of view, and when one element is referred to as being positioned above or below another element, it is said that one element is placed directly above or below another element or an additional element is interposed between them. It includes everything that can be done. In addition, one of ordinary skill in the art may implement the spirit of the present application in various other forms without departing from the technical spirit of the present application. In addition, in the drawings, the same reference numerals refer to substantially the same elements.

1 is a perspective view of a composite optical sheet according to an embodiment of the present invention, Figure 2 is a cross-sectional view of a composite optical sheet according to an embodiment of the present invention. 1 and 2, the composite optical sheet 100 according to an embodiment of the present invention includes a first optical sheet 130 including an adhesive layer 120 on one surface thereof; And a second optical sheet 180 formed under the adhesive layer 120 and including an optical pattern 170 on one surface thereof. The optical pattern 170 includes a plurality of first prisms 150 and a plurality of second prisms 160 having a height lower than that of the first prism 150, and the vertices of the first prisms 150 are the adhesive layer 120. ) May be penetrated into the adhesive layer 120, and the vertices of the second prism 160 may contact the adhesive layer 120.

In the present invention, the 'vertex' refers to the point where the height of the optical pattern is the highest in the optical pattern (eg prism), and 'penetration' refers to the vertex of the optical pattern by entering the interior of the adhesive layer through the adhesive layer. It means to exist inside the adhesive layer. However, the 'penetration' is penetrated when the 'peak' enters into the adhesive layer. The contact with the other surface opposite to one surface of the adhesive insect is not excluded. In addition, 'penetration depth' means a vertical length formed by the optical pattern penetrating into the adhesive layer.

The first optical sheet 130 is positioned on the second optical sheet 180, the first optical sheet 130 is the first base film 110; And an adhesive layer 120 formed on one surface of the first base film 110, and the first base film 110 has a light exit surface that is the other surface and a light incident surface that is one surface on which the adhesive worm 120 is formed. The light emitted from the two optical sheets 180 may be received and emitted to the upper portion of the first optical sheet 130.

The second optical sheet 180 may include a second base film 140; And an optical pattern 170 formed on one surface of the second base film 140, and the second base film 140 has a light exit surface that is one surface on which the optical pattern is formed and a light incident surface that is the other surface, and is a light source or a light guide plate. (Not shown in FIG. 1), etc., light may be emitted to the first optical sheet 130.

By allowing the vertices of the first prism 150 to penetrate into the adhesive layer 120, the adhesion between the first optical sheet and the second optical sheet may be enhanced. In this case, the first optical sheet and the second optical sheet may be integrated by the adhesive layer 120. The 'integration' refers to a state in which the first optical sheet and the second optical sheet are not separated from each other independently.

The thicknesses of the first base film 110 and the second base film 140 may be the same or different, but are not limited thereto, and may be about 20 τη to 300, specifically about 100 pm to 250 / m, respectively. It is possible to prevent the phenomenon of migration of the composite optical sheet in the range, to ensure rigidity, and to slim the composite optical sheet.

An air layer 50 is formed between the adhesive layer 120 and the optical pattern 170 to prevent a decrease in luminance. In addition, the air layer 50 may be layered with a material having a refractive index similar to air (eg, a refractive index of about 1.0 to 1.5).

The optical pattern 170 may be formed integrally with the base film as an optical member for refracting the light passing through the second base film to have a constant direction, and the base film by compression molding the film used as the base film. It may be formed on the other side of the. 1 and 2 illustrate a prism pattern composed of a first prism and a second prism as an optical pattern, but the present invention is not limited thereto. And two kinds of micro lenses, lenticular lenses, pyramid lenses, etc. having different heights may be applied.

The cross-sections of the first prism 150 and the second prism 160 may be the same or different, and the cross-section may be a triangle, the prism may be a triangular prism.

2 shows an example in which the first prism penetrates the adhesive layer and the second prism is in contact with the adhesive layer. Referring to FIG. 2, the first prism 150 has a height HI and the second prism 160 has a height H2. Ridges of the mountains of the second prism 160 are in line contact with the adhesive layer 120. On the other hand, since the first prism 150 has a height greater than that of the second prism 160, the first prism 150 penetrates the adhesive layer 120 by the height difference H1-H2 between the first prism and the second prism to form a surface bond. The penetration depth D1 formed by the first prism 150 penetrating the adhesive layer 120 in a direction perpendicular to one surface of the second base film is equal to the difference between the heights H1-H2 of the first prism and the second prism. Have the same value. However, the penetration depth D1 may not exceed the thickness of the adhesive layer 120. Accordingly, the thickness A of the adhesive layer 120, the depth D1 through which the first prism 150 penetrates the adhesive layer, the first prism height HI, and the second prism height H2 may satisfy the following Equation 1. have. ^J

A ≥ D1 = H1-H2> 0

The vertex angle of the first prism 150 and the vertex angle of the second prism 160 may be the same or different, and may each be about 30 ^° to 150 ^° . The 'vertical angle' means an angle facing the second optical sheet of the prism.

The first prism 150 and the second prism 160 have constant heights HI and H2 along the prism arrangement direction, respectively. HI and H2 may be about 10-50 μιη, preferably about 10 / -40, although not limited.

The ratio of H2 to HI (H1 / H2) may be greater than about 1 and less than or equal to 2, and the difference between HI and H2 (H1-H2) may be greater than 0 and less than or equal to about 30. In the case of having the above range, there is an advantage of high luminance. The pitch PI of the first prism may be about 20 to 100 m, and the pitch P2 of the second prism may be about 20 to 80 zm. In the above range, it may have the effect of condensing light from the light source to improve the brightness.

The ratio P1 / P2 of the pitch P2 of the second prism 160 to the pitch P1 of the first prism 150 may be about 1 to 2. In the case of having the above range, there is an advantage of high luminance.

The first prism 150 and the second prism 160 may be alternately arranged or may be arranged with a constant period. For example, the prism pattern may have a repetition period in which the first prism is arranged 2N + 1th after the second prism is arranged 2N consecutively (N = integer). In the case of having the arrangement period as described above, there is an advantage of high luminance. FIG. 2 illustrates a case where N = 2, that is, when the first prism 150 is arranged after four consecutive second prisms 160 are arranged. As another example, when N = 3, the second prism may be arranged six consecutively and then have a repetition period in which the first prism is arranged.

The first base film, the second base film, the first prism and the second prism may be formed of the same material or different materials. Specifically, as a transparent material in the visible light region, it may be made of a thermoplastic resin or a composition comprising the same. Examples of the thermoplastic resins include polyester resins including polyacetal resins, (meth) acrylic resins, polycarbonate resins, styrene resins, polyethylene naphthalate resins, vinyl resins, polyphenylene ether resins, polyolefin resins, cycloolefin resins, and acrylics. It may include one or more of polyolefin resins, fluorine-based resins including ronitrile-butadiene-styrene copolymer resins, polyacrylate resins, polyarylsulfone resins, polyethersulfone resins, polyphenylene sulfide resins, polyethylene resins, This is not restrictive. As used herein, '(meth) acryl' refers to acrylic and / or methacryl.

The first base film, the second base film, the first prism, and the second prism may be formed by further including a light diffusing agent in addition to the resin. The light diffusing agent may be an organic light diffusing agent, an inorganic light diffusing agent or a combination thereof, and an organic light diffusing agent may be used.

(Meth) acrylic particles, siloxane particles, melamine particles, polycarbonate particles, styrene particles and the like may be included, and may be used alone or in combination. The organic light diffusing agent may be spherical beads having an average particle diameter (D50) of about 2 to 20 / mm 3. The inorganic light diffusing agent may be calcium carbonate, barium sulfate, titanium dioxide, aluminum hydroxide, silica, glass, talc, mica, white carbon, magnesium oxide, zinc oxide, or the like, but is not limited thereto. The inorganic light diffusing agent may be a spherical bead having an average particle diameter (D50) of about 2 to 20. In addition, the hard coating layer may be formed in a flat surface, but may further increase the diffusion effect by forming irregularities. The light diffusing agent may be included in about 0.1 to 10 parts by weight based on 100 parts by weight of the resin.

The adhesive layer may be formed of a composition including monomers, oligomers, resins, and the like, which are excellent in transparency and may form crosslinks suitable for maintaining the shape of the optical structure. For example, epoxy resin-Lewis acid, polyethylene, unsaturated polyester-styrene, acrylic acid or methacrylic ester can be used. Among them, resin having excellent transparency is used for acrylic or methacrylic ester resin. Can be used. For example, there are oligomers such as urethane acrylate or methacrylate, epoxy acrylate or methacrylate, polyester acrylate or methacrylate, and alone with an acrylate or methacrylate monomer having a polyfunctional or monofunctional group. Or may be used in combination.

Although not shown in FIG. 1, a hard coating layer may be further formed on the rear surface of the second base film to prevent the composite optical sheet from being damaged by a structure (eg, a light guide plate or various sheets) formed at the bottom when the backlight unit is mounted. . The hard coating layer may be formed using various resins in a conventional manner, and further include the light diffusing agent to increase the light diffusing effect.

In addition, although not shown in FIG. 1, a pattern selected from the group consisting of a micro lens pattern, an emboss pattern, a lenticular lens pattern, a prism pattern, a pyramid pattern, and a combination thereof may be further formed on another surface of the second optical sheet. have. As an example, when an embossed pattern is further formed on the rear surface of the second base film, the embossed pattern is an irregular embossed or intaglio irregularity, and may form irregularities by hitting the surface of the roll with beads having a diameter of about 1 to 200 μπι. The embossed pattern, in particular, the irregular embossed pattern can scatter light to prevent scratches and increase hardness in the prism sheet. Hereinafter, a composite optical sheet according to another embodiment of the present invention will be described in more detail with reference to FIGS. 3 and 4. 3 and 4 are cross-sectional views of a composite optical sheet according to another embodiment of the present invention.

3 and 4, the composite optical sheet 200 according to another embodiment of the present invention may include a first optical sheet 130 including an adhesive layer 120 on one surface thereof; And a second optical sheet 185 formed under the adhesive layer 120 and including an optical pattern 175 on one surface thereof, wherein the optical pattern 175 includes a plurality of first prisms 155 and a first prism. And a plurality of second prisms 165 having a height lower than that of 155, wherein the vertices of the first prism 155 and the second prism 165 both penetrate the adhesive layer 120 and exist inside the adhesive layer 120. Can be. The composite optical sheet 200 according to the present exemplary embodiment is different from the exemplary embodiment of the present invention in that the vertices of the first prism 155 and the second prism 165 are both present in the adhesive layer 120. Since the vertices of the first prism 155 and the second prism 165 are both present in the adhesive layer 120, the adhesive force is improved, while the decrease in luminance can be suppressed by varying the penetration depth into the adhesive layer 120.

The ratio (D1 / D2) of the first penetration depth D1 through which the first prism 155 penetrates the adhesive layer 120 and the second penetration depth D2 through which the second prism 165 penetrates the adhesive layer 120. May be about 1.5 to 7. It is possible to optimally secure the brightness and adhesion in the above range and to prevent the moiré phenomenon.

Referring to FIG. 3, the vertex angle _α of the first prism 155 and the vertex angle β of the second prism 165 are the same, and the pitch P1 of the first prism 155 is the second prism 165. ) May be greater than the pitch (Ρ2). As such, when the vertices of the first prism 155 and the second prism 165 are the same, and the pitch P1 of the first prism is larger than the pitch Ρ2 of the second prism, the brightness is high and the adhesive strength is excellent. There is this.

Hereinafter, a composite optical sheet according to another embodiment of the present invention will be described in more detail with reference to FIGS. 5 and 6. 5 is a perspective view of a composite optical sheet according to still another embodiment of the present invention, and FIG. 6 is a cross-sectional view of the composite optical sheet according to another embodiment of the present invention.

5 and 6, the composite optical sheet 300 according to another embodiment of the present invention may include a first optical sheet 130 including an adhesive layer 120 on one surface thereof; And A second optical sheet 290 is formed below the adhesive layer 120 and includes an optical pattern 280 on one surface thereof. The optical pattern 280 includes a plurality of first prisms 250 and first prisms 250. A plurality of second prisms 260 lower in height, and a plurality of third prisms 270 lower in height than the second prism 260.

The apex 251 of the first prism 250 penetrates the adhesive layer 120 and exists inside the adhesive layer 120, and the apex 261 of the second prism 260 penetrates the adhesive layer 120 to attach the adhesive layer 120. ), The apex 271 of the third prism 270 does not penetrate the adhesive layer 120, and the penetration depth D1 of the adhesive layer 120 of the first prism 250 is the second prism 260. ) May be greater than the penetration depth D2 of the adhesive layer 120. As a result, the first prism penetrates into the adhesive layer and the vertices are completely penetrated into the adhesive layer, thereby improving adhesion between the first optical sheet and the second optical sheet, and the third prism is completely separated from the adhesive layer without penetrating into the adhesive layer, thereby decreasing luminance. And the second prism penetrates into the adhesive, thereby lowering the penetration depth of the adhesive layer relative to the first prism, thereby maintaining the adhesive force between the first optical sheet and the second optical sheet but reducing the adhesion area with the adhesive layer relative to the first prism. It is possible to compensate for the decrease in luminance and to effectively avoid moiré caused by the period of the adhesion area between the first prism and the second prism. That is, in the composite optical sheet according to the present embodiment, the heights of the first prism, the second prism, and the third prism are different from each other so as to secure the adhesive force and increase the luminance.

The first prism 250, the second prism 260, and the third prism 270 are integrally formed with the second base film 140 on one surface of the second base film 140, respectively.

The first prism 250 may be formed at one surface of the second base film 140 with a repetition period or randomly formed. The repetition period does not mean a distance between the first prism repeatedly formed in the second optical sheet, but rather means that the first prism is arranged in a predetermined order. Referring to FIG. 4, a second prism 260 is formed between the first first prism 250 and the second first prism 250 ′.

260 ') and the third prisms 270, 270', and 270 "can be arranged. As a result, it is possible to secure the adhesive force, prevent the brightness from being lowered, and avoid moiré generation.

At this time, the second prism and the third prism may be randomly arranged between the first prism, respectively, but one second prism and a plurality of third prisms may be arranged. The repeating pattern including the prism may be repeatedly formed one or more times. Specifically, the repeating pattern may have a period of 4M, 5M, or 6M, where M is an integer of 1 to 30. For example, when the period of the repeating pattern is 4M (M = 10), a pattern including one second prism and three third prisms, that is, four prisms is repeated ten times. In this case, the second prism may be arbitrarily arranged anywhere in the first to fourth times of the repeating pattern, or may be arranged at the same period as the repeating pattern. In the above example, when the period of the repeating pattern and the second prism is 4M (M = 10), the second prism is arranged at the 4th, 8th, 12th, ... 40th position. In this case, a third prism may be arranged between the second prism or between the second prism and the first prism. 4 includes a second prism 260, 260 ′, 260 ′ ′ and a third prism 270, 270 ′, 270 ′ ′ with a period of 4M between the first prisms 250, 250 ′. A repeating pattern is formed and the second prism also illustrates a structure having a period of 4M. That is, a structure in which a pattern including three third prisms 270 and one second prism 260 is repeated between the first prisms 25 250 ′ is not limited thereto.

Since the first prism has a large penetration depth inside the adhesive layer to secure a wider adhesive area than the second prism, the first prism must increase the adhesive force, and the second prism must have an appropriate period between patterns while compensating for the adhesive force. Only then can it increase the adhesion and avoid moiré. Thus, the adhesive area S1 between the first prism and the adhesive layer, and the adhesive area S2 between the second prism and the adhesive layer may have a relationship of the following equation 2:

S1> S2X)

When SI is larger than S2, the composite optical sheet can secure the adhesive force and at the same time avoid moiré generation. The 'adhesion area' means the total area of the prism and the adhesive contact.

Since the vertices of the first prism and the second prism are both penetrated into the adhesive layer, in order to secure the adhesive force and prevent the decrease in brightness, the thickness of the adhesive layer (A), the height of the first prism (HI), and the height of the second prism (H2). ) May have a relationship of the following formula 3:

<Equation 3> 1> (H1-H2) / A> 0.5

In the above range, the composite optical sheet can secure the adhesive force and at the same time prevent the decrease in brightness and avoid moiré generation.

Specifically, D1 may be about 10 or less, specifically about O.Om to 7, D2 may be about 0 to 2 μηι or less, A may be about 1 to 10 / m, specifically about 3 to 7 / m, In the range, the composite optical sheet can secure the adhesive force, prevent the decrease in luminance, and avoid the moiré generation.

The ratio H1 / H2 of the height HI of the first prism to the height H2 of the second prism is greater than about 1 and less than or equal to 5 and less than the height H2 of the second prism with respect to the height H3 of the third prism. ) Ratio (H2 / H3) may be more than about 1 to 5 or less, in the above range, the composite optical sheet can secure the adhesive force and at the same time prevent the brightness deterioration.

More specifically, the difference H1-H2 between the height HI of the first prism and the height H2 of the second prism is about 10 j or less, the height H2 of the second prism and the height H3 of the third prism. ), The difference (H2-H3) may be about 20 μια or less, and in the above range, the composite optical sheet can secure the adhesive force, prevent luminance decrease, and avoid moiré generation.

More specifically, Η1> Η2> Η3> 0, HI may be about 7 to 80, H2 may be about 6 j¾m to 60 im, H3 may be about 5 im to 40 imA, and in the above range, the composite optical sheet may be It is possible to secure the adhesive force and at the same time prevent the decrease in luminance.

The pitch P1 of the first prism, the pitch P2 of the second prism, and the pitch P3 of the third prism may be P1> P2> P3> 0. In the above range, the composite optical sheet can secure the adhesive force and at the same time prevent the decrease in brightness and avoid moiré generation.

Specifically, P1 / P2 may be greater than or equal to about 1 and 2 or less, and P2 / P3 may be greater than or equal to about 1 and 2 or less, and in the above range, the luminance may be high. More specifically, P1 may be about 7 to 280, P2 may be about to 210, and P3 may be about 5 to 140. In the above range, the composite optical sheet can secure the adhesive force and at the same time prevent the decrease in brightness and avoid moiré generation.

The vertex angle of the first prism α, the vertex angle of the second prism β and the vertex angle of the third prism may be the same or different, and may be about 60 ° to 120 °, respectively. In the above range, the composite optical sheet can secure the adhesive force and at the same time prevent the decrease in brightness and avoid moiré generation.

The third prism may be formed of the same material or different materials from the first base film, the second base film, the first prism, and the second prism.

Hereinafter, a composite optical sheet according to another exemplary embodiment of the present invention will be described with reference to FIG. 7. 7 is a cross-sectional view of a composite optical sheet according to another embodiment of the present invention. Referring to FIG. 7, the composite optical sheet 400 according to another embodiment of the present invention may include a first optical sheet 130 including an adhesive layer 120 on one surface thereof; And a second optical sheet 290 formed under the adhesive layer 120 and including an optical pattern 280 on one surface thereof, wherein the optical pattern 280 includes a plurality of first prisms 250 and a first prism. And a plurality of second prisms 260 having a height lower than 250, and a plurality of third prisms 270 having a height lower than the second prism 260, and the apex of the first prism 250 is formed by an adhesive layer ( It penetrates 120 and exists inside the adhesive layer 120, the vertices of the second prism 260 contact the adhesive layer 120, and the vertices of the third prism 270 do not penetrate the adhesive layer 120, and the first The penetration depth D1 of the adhesive layer 120 of the prism 250 may be larger than the penetration depth D2 of the adhesive layer 120 of the second prism 260. It is substantially the same as the composite optical sheet of another embodiment of the present invention described above with reference to FIGS. 5 and 6, except that the vertices of the second prism do not penetrate into the adhesive layer and contact the adhesive layer. Since the second prism does not penetrate into the adhesive layer and the adhesive force is secured only by the penetration of the first prism, the luminance of the composite optical sheet may be increased.

Hereinafter, a composite optical sheet according to another embodiment of the present invention will be described with reference to FIG. 8. 8 is a cross-sectional view of a composite optical sheet according to another embodiment of the present invention. Referring to FIG. 8, the composite optical sheet 500 according to another embodiment of the present invention may include a first optical sheet 130 including an adhesive layer 120 on one surface thereof; And a second optical sheet 295 formed under the adhesive layer 120 and including an optical pattern 285 on one surface thereof, wherein the optical pattern 285 includes a plurality of first prisms 250 and first prisms ( A plurality of second prisms 260 lower in height than 250, and a plurality of third prisms 275 lower in height than second prism 260, wherein the vertices of first prism 250 are adhesive layers 120. Penetrates) and exists inside the adhesive layer 120, The vertices of the second prism 260 penetrate the adhesive layer 120 and exist inside the adhesive layer 120, and the vertices of the third prism 275 do not penetrate the adhesive layer 120, but do not penetrate the first prism 250. The penetration depth of the adhesive layer 120 is greater than the penetration depth of the adhesive layer 120 of the second prism 260, and the third prism 275 includes a plurality of neighboring prisms (eg, two to five) overlapping each other. Can be formed. It is substantially the same as another embodiment of the present invention described above with reference to FIGS. 5 and 6 except that the third prisms are overlapped. Hence, hereinafter, the overlapping third prism will be described. By overlapping the third prism, it is possible to implement a light collecting effect. The 'nesting' means that the prism A and the prism B are combined such that at least one side constituting the prism A is included in the neighboring prism B. 8 illustrates a structure in which three prisms are overlapped in the composite optical sheet, but is not limited thereto.

Hereinafter, a composite optical sheet according to another exemplary embodiment of the present invention will be described with reference to FIG. 9. 9 is a cross-sectional view of a composite optical sheet according to another embodiment of the present invention. 9, the composite optical sheet 600 according to another embodiment of the present invention may include a first optical sheet 130 including an adhesive layer 120 on one surface thereof; And a second optical sheet 390 formed under the adhesive layer 120 and including an optical pattern 380 on one surface thereof, wherein the optical pattern 380 includes a plurality of first prisms 350 and a first prism ( A plurality of second prisms 360 having a height lower than 350, and a plurality of third prisms 370 having a height lower than the second prism 360, wherein the vertices of the first prism 350 have an adhesive layer 120. ) Penetrates into the adhesive layer 120, the apex of the second prism 360 penetrates into the adhesive layer 120, and exists inside the adhesive layer 120, and the apex of the third prism 370 is the adhesive layer 120. ), The penetration depth of the adhesive layer 120 of the first prism 350 is greater than the penetration depth of the adhesive layer 120 of the second prism 360, and the first prism 350 and the second prism 360 Each of the third prism 370 may have a vertex formed on a curved surface. It is substantially the same as another embodiment of the present invention described above with reference to FIGS. 5 and 6 except that the vertex is formed on a curved surface. The apexes may be formed on the curved surface instead of being formed on the unfavorable portion of the prism acid, thereby increasing the adhesive force. The radius of curvature of the curved surface may be about 1 to 3, Hereinafter, a composite optical sheet according to another exemplary embodiment of the present invention will be described with reference to FIG. 10. 10 is a cross-sectional view of a composite optical sheet according to another embodiment of the present invention. Referring to FIG. 10, the composite optical sheet 700 according to another embodiment of the present invention may include a first optical sheet 130 including an adhesive layer 120 on one surface thereof; And a second optical sheet 490 formed under the adhesive layer 120 and including an optical pattern 480 on one surface thereof, wherein the optical pattern 480 includes a plurality of first microlenses 450 and first microns. A plurality of second microlenses 460 having a lower height than the lens 450, and a plurality of third microlenses 470 having a lower height than the second microlens 460, and including a first microlens 450 A vertex of the penetrates the adhesive layer 120 and exists inside the adhesive layer 120, a vertex of the second microlens 460 is in contact with the adhesive layer 120, and a vertex of the third microlens 470 is the adhesive layer 120. The penetration depth of the adhesive layer 120 of the first microlens 450 may be greater than the penetration depth of the adhesive layer 120 of the second microlens 460 without penetrating into it. Substantially the same as another embodiment of the present invention described above with reference to FIGS. 5 and 6 except that a microlens pattern is formed in place of the prism and the apex of the second microlens pattern does not penetrate into the adhesive layer and contacts the adhesive layer. Do. By forming a micro lens pattern instead of a prism pattern, the adhesion area can be increased.

Hereinafter, a composite optical sheet according to another exemplary embodiment of the present invention will be described with reference to FIG. 11. 11 is a cross-sectional view of a composite optical sheet according to another embodiment of the present invention. Referring to FIG. 11, the composite optical sheet 800 according to another embodiment of the present invention may include a first optical sheet 130 including an adhesive layer 120 on one surface thereof; And a second optical sheet 290 formed under the adhesive layer 120 and including an optical pattern 280 on one surface thereof, wherein the optical pattern 280 includes a plurality of first prisms 250 and a first prism ( A plurality of second prisms 260 having a height lower than 250, and a plurality of third prisms 270 having a height lower than the second prism 260, and the apex of the first prism 250 is an adhesive layer 120. ) Penetrates into the adhesive layer 120, and a vertex of the second prism 260 penetrates into the adhesive layer 120, and exists inside the adhesive layer 120, and a vertex of the third prism 270 is an adhesive layer 120. ), The penetration depth D1 of the adhesive layer 120 of the first prism 250 is larger than the penetration depth D2 of the adhesive layer 120 of the second prism 260, and is larger than that of the adhesive layer 120. Towards the first optical sheet 130 A nuclear accidental micro lens pattern 111 may be formed. It is substantially the same as another embodiment of the present invention described above with reference to FIGS. 5 and 6 except that the nuclear accidental micro lens pattern 111 is further formed on the first optical sheet.

The pitch of the nucleus blade micro lens may be about 20 to 100, and may be about 10 to 50 in height. In the above range, it may have the effect of condensing light from the light source to improve the brightness. Each unit lens constituting the nuclear accident micro lens may have a hemispherical top surface and a bottom surface contacting the first base film 110.

In addition, although not shown in FIG. 11, an embodiment in which at least one of a non-nuclear accidental microlens pattern, an embossed pattern, a lenticular lens pattern, a prism pattern, and a pyramid pattern is formed in place of the nuclear accidental microlens is also within the scope of the invention Can be included.

Hereinafter, a liquid crystal display according to an exemplary embodiment of the present invention will be described with reference to FIG. 12. 12 is a cross-sectional view of a liquid crystal display according to an exemplary embodiment of the present invention. Referring to FIG. 12, the liquid crystal display device 90Q according to an exemplary embodiment of the present invention may include a liquid crystal display panel 710, a first polarizing plate 720 formed on an upper portion of the liquid crystal display panel 710, and a lower portion of the liquid crystal display panel 710. And a backlight unit 740 formed below the second polarizing plate 730 and the second polarizing plate 730, and the backlight unit 740 guides light emitted from the light source 741 and the light source 741. 742, a reflection sheet 743 disposed below the light guide plate 742, a diffusion sheet 744 disposed above the light guide plate 742, and an optical sheet 745 disposed above the diffusion sheet 744. The optical sheet 745 may include an optical sheet according to embodiments of the present invention.

The light source 741 generates light, and various light sources such as a line light source lamp or a surface light source lamp, CCFL, or LED may be used. The light source cover 746 may be further formed outside the light source 741 to protect the light source.

The light guide plate 742 may serve to guide light incident from the light source 741 to the diffusion sheet 744.

The reflective sheet 743 may reflect light generated from the light source 741 to be incident back to the light guide plate 742 to increase the efficiency of the light. The diffusion sheet 744 diffuses the light incident from the light guide plate 742 and supplies it to the optical sheet 745.

Although not shown in FIG. 12, a protective sheet may be further formed between the optical sheet 745 and the second polarizing plate 730.

The liquid crystal display panel 710 includes a liquid crystal panel including a liquid crystal cell layer encapsulated between a first substrate and a second substrate, wherein the liquid crystal cell layer includes a VA vertical alignment (IP) mode, an in place switching (IPS) mode, and an FFS ( fringe field switching mode, TNCtwisted nematic mode, and the like.

The first polarizing plate 720 and the second polarizing plate 730 may include a polarizer, a protective film formed on the polarizer, and / or a retardation film.

[Form for implementation of invention]

Hereinafter, the configuration and operation of the present invention through the preferred embodiment of the present invention will be described in more detail. However, this is presented as a preferred example of the present invention and in no sense is it to be construed as limiting the present invention.

Examples 1-2 and Comparative Examples 1-3

Example 1

The first optical sheet includes a first base film (polyester film) having a thickness of 125 and an adhesive layer (urethane acrylate resin) having a thickness of 4 formed on the light incidence surface of the first base film, and the light of the first base film. On the exit surface, a regular array nuclear accident micro lens pattern having a height of 12 ai and a pitch of 40 / kg was formed.

The second optical sheet formed a prism pattern in a cycle of arranging four second prisms on one surface of a second base film (polyester film) having a thickness of 125 and then arranging one first prism.

The first prism has a triangular cross section, the height of the prism is 29 p, the pitch is 58, and the second prism has a triangular cross section, the prism has a height of 25 m, a pitch of 50, and the first prism penetrates the adhesive. Penetrated to depth 4 / m.

After measuring the physical properties of the prepared composite optical sheet described in Table 2 the results.

Example 2 The first prism has a triangular cross section, the prism height is 33 urn, the pitch is 66, and the second prism has a triangular cross section, the prism height is 25 _m , the pitch is 50, and the first prism penetrates the adhesive layer having a thickness of 8. Example except that it penetrated to depth 8

The composite optical sheet was prepared in the same manner as in Example 1, and after measuring the physical properties, the following table

2 shows the result.

Comparative Example 1-3

The composite optical sheet was prepared in the same manner as in Example 1 except that only the first prism having a cross section having a triangle, the height and pitch of the prism having the values shown in Table 1 below, and the penetration depths were 2, 4, and 8, respectively. It was prepared, and the results are described in Table 2 after measuring the physical properties.

TABLE 1

TABLE 2

When two kinds of prisms having different heights are applied as in Examples 1 and 2, it can be seen that the luminance is improved. In addition, in the case of applying two kinds of prisms to increase the thickness and penetration depth of the adhesive, as in Example 2, both brightness and adhesion Excellent. It can be seen that in Comparative Examples 2 and 3, all the vertices of the first prism penetrated the adhesive layer, so that the adhesive strength was excellent, but the luminance decreased.

(1) Luminance gain: A diffusion sheet and a prism sheet were molded into an edge type backlight unit for a 32-inch LCD using an LED light source. Luminance was measured using an SR3 spectroradiometer from TOPCON. Luminance gain is a rate of change of the luminance value after molding the optical sheet and calculated as the ratio of the luminance value after the optical sheet bonding to the luminance value before the optical sheet bonding.

The luminance measurement measures the center point of the measurement model, and three prism sheet samples were prepared for each measurement sample. The luminance measurement value (A) in the diffusion sheet state is obtained, and the luminance measurement value (B) after the sample to be measured is molded on the diffusion sheet. The luminance gain was obtained by the ratio B / A of B to A.

(2) Relative luminance: The percentage value (G2 / G1 × 100) of the luminance gain G2 of the sheet of the example or the comparative example was obtained for the luminance gain Gl of the comparative example 1, respectively.

(3) Adhesion: The prepared composite optical sheet was cut into a specimen having a width of 25 mm and a length of 200 mm, and the fracture strength was measured when the composite optical sheet was pulled in a 180 ^° direction at a speed of 300 mm / min using a UTM.

Example 3-4 and Comparative Examples 4-10

Example 3

The first optical sheet includes a base film (PET film) having a thickness of 125 and an adhesive layer (urethane acrylate resin) having a thickness of 8 formed on the light incidence surface of the base film, wherein the light exit surface of the base film has a height of 12 m, A regular array nuclear accident microlens pattern having a pitch of 40 was formed.

The second optical sheet formed a prism pattern at a cycle of arranging four second prisms on one surface of a base film (polyester film) having a thickness of 125; Mil and then arranging one first prism.

The first prism had a triangular cross section, a prism height HI of 29 m, a pitch PI of 58 urn, a vertex angle of 90 degrees, and penetrated the adhesive layer with a first penetration depth (D1) of 8 kPa. 2 prism has a cross section, the prism height (H2) is 25 ^ η, The pitch P2 was 50 m, the vertex angle was 90 degrees, and penetrated the adhesive layer by the 2nd penetration depth D24.

After measuring the physical properties of the prepared composite optical sheet, the results are described in Table 4 below.

Example 4

The height (HI, H2) and the pitch (PI, P2) of the first prism and the second prism have the numerical values shown in Table 3 below, the first penetration depth (D1) of the first prism is 5 mi, the second prism The composite optical sheet was manufactured in the same manner as in Example 3, except that the second penetration depth (D2) of 1 was 1, and the results are described in Table 4 after the measurement of the physical properties.

Comparative Example 4-6

Only the first prism having the height HI and the pitch P1 described in Table 3 was used, and the composite was fabricated in the same manner as in Example 3 except that the first penetration depths D1 were 0, 4, and 8, respectively. An optical sheet was prepared, and the results were described in Table 4 after measuring physical properties.

Comparative Example 7

The height (HI, H2) and the pitch (PI, P2) of the first prism and the second prism have the numerical values shown in Table 1 below, the first prism is in contact with the adhesive layer (D1 = 0), and the second prism is connected with the adhesive layer. A composite optical sheet was manufactured in the same manner as in Example 3, except that the prism patterns were formed to be spaced apart from each other. After measuring physical properties, the results are shown in Table 4 below.

Comparative Example 8

The height (HI, H2) and the pitch (PI, P2) of the first prism and the second prism have the numerical values shown in Table 3 below, the first prism has a first penetration depth (D1) of 4, and the second prism A composite optical sheet was manufactured in the same manner as in Example 3, except that the adhesive layer was in contact with the adhesive layer (D2 = 0), and the results are described in Table 4, after measuring the physical properties.

Comparative Example 9

The height (HI, H2) and the pitch (PI, P2) of the first prism and the second prism have the numerical values shown in Table 3 below, the first prism has a crab 1 penetration depth (D1) of 4, and the system 2 The prism prepared a composite optical sheet in the same manner as in Example 3 except that the second penetration depth (D2) is 0.5, and the results are shown in Table 4 after measuring the physical properties.

Comparative Example 10

The height (HI, H2) and the pitch (PI, P2) of the first prism and the second prism have the numerical values shown in Table 1 below, the first prism has a first penetration depth (D1) of 3 ai, and the second prism The composite optical sheet was manufactured in the same manner as in Example 3 except that the second penetration depth (D2) was 2.5, and the results are described in Table 4 after the measurement of the physical properties.

TABLE 3

TABLE 4

As shown in the results of Table 4, Example 3-4, in which the ratio (D1 / D2) of the first penetration depth D1 and the second penetration depth D2 falls within the scope of the present invention, is excellent in brightness and adhesion. It can be seen that the moiré phenomenon did not occur.

On the other hand, in Comparative Example 4 using only the first prism in contact with the adhesive layer, the adhesion was remarkably decreased, and Comparative Example 5-6 and the penetration length ratio (D1 / D2) using only the first prism penetrating the adhesive layer exceeded the scope of the present invention. In Comparative Example 9-10, the luminance and the adhesive force were deteriorated, and Comparative Example 7 in which the System 2 prism was spaced apart from the adhesive layer and Comparative Example 8 in which the crab 2 prism was in contact with the adhesive layer showed that the adhesive force was deteriorated and the moire phenomenon occurred.

Property measurement method

(1) Luminance gain: Measured in the same manner as in Example 1.

(2) Relative luminance: The percentage value (G2 / G1 × 100) of the luminance _ga in (G2) of the sheet of the example or the comparative example with respect to the luminance gain G1 of Example 3 was obtained.

(3) Adhesive force: It measured by the same method as Example 1.

(4) Moiré occurrence: The panel and backlight unit (BLU) were separated from the 32-inch CY-HF320CSLV1H model. The composite optical sheet of the Example and the comparative example was cut in accordance with the BLU size (width X length, 700 誦 X 400 誦). The panel and the frame were reassembled after mounting the composite optical sheet on the BLU. Turn on the TV assembled in the darkroom and set the wallpaper to WHITE. Moiré is a wavy pattern and is visually recognized. Moiré by inspecting the occurrence of moiré from up, down, left, and right viewing angles Determine the status quo. If the moire was not visually recognized, X, if the moire was visually acknowledged, it was evaluated as zero.

Example 5-9 and Comparative Examples 11-13

Example 5

An adhesive layer (urethane acrylate resin, Shina T & C) having a thickness of 3 was formed on one surface of a first base film (PET (polyethylene terephthalate) film) having a thickness of 125 to prepare a first optical sheet.

Pitch 74 m, height 37 βΆ, triangular first prism, pitch 70 im, height 35 iM, second prism triangular in cross section, pitch 50 ^ m on one surface of the second base film (PET film) having a thickness of 125 A third prism having a height of 25 pm and having a triangular cross section is formed, wherein a third pattern of three third prisms is continuously arranged, followed by a repeating pattern in which a pattern in which one second prism is arranged is repeatedly arranged 12 times. The second optical sheet was manufactured such that a pattern in which three prisms were continuously arranged (total number of prism patterns: 51) was arranged between one first prism and one immediately neighboring first prism. The vertex of the first prism penetrates into the adhesive layer and the penetration depth of the adhesive layer of the first prism is 3, the vertex of the second prism penetrates the interior of the adhesive layer and the penetration depth of the adhesive layer of the second prism is 1, and the vertex of the third prism is The first optical sheet and the second optical sheet were bonded to each other so as not to penetrate into the adhesive layer to prepare a composite optical sheet.

Example 6

In Example 5, the pitch and height of the first prism, the second prism, the third prism, the penetration depth of the adhesive layer of the first prism, the second prism, and the thickness of the adhesive layer were changed as shown in Table 5 (unit: mi) below. Except that a composite optical sheet was prepared in the same manner as in Example 5.

Example 7

A composite optical sheet was prepared in the same manner as in Example 5, except that the vertex of the crab 2 prism was in contact with the adhesive layer in Example 5.

Example 8

A composite optical sheet was manufactured in the same manner as in Example 5, except that the vertex of the first prism, the vertex of the crab 2 prism, and the vertex of the third prism were formed in a curved surface. Example 9

In Example 5, a composite optical sheet was manufactured in the same manner as in Example 5, except that the first prism, the second prism, and the third prism were each changed to a microlens pattern having a pitch and a width shown in Table 5 below. .

Comparative Example 11

In Example 5, using a second optical sheet in which only a first prism having a pitch 66 βη, a height of 33 tm, and a triangular cross section was continuously arranged on one surface of a second base film (PET film) having a thickness of 125, and the first prism The composite optical sheet was prepared in the same manner as in Example 5 except that the penetration depth of the adhesive layer was 3 im and the thickness of the adhesive layer was 3.

Comparative Example 12

In Comparative Example 11, a composite optical sheet was manufactured in the same manner as in Comparative Example 11, except that the penetration depth of the adhesive layer of the first prism and the thickness of the adhesive layer were changed as in Table 5 below.

Comparative Example 13

In Example 5, one prism having a pitch of 74 im, a height of 37 im, and a triangle having a triangular cross section on one surface of a second base film (PET film) having a thickness of 125, a pitch of 50 pm, a height of 25 μ, and a third prism having a triangular cross section And a second optical sheet in which 51 third prisms are continuously arranged between the first prism and the immediately neighboring first prism, and the penetration depth of the adhesive layer of the first prism is 3, of the third prism. A composite optical sheet was manufactured in the same manner as in Example 5, except that the first optical sheet and the second optical sheet were adhered to each other so as not to penetrate into the adhesive layer.

TABLE 5

TABLE 6

As shown in Table 6, the composite optical sheet of the present invention can secure the adhesive force, improve the brightness decrease and at the same time avoid the moire generation.

On the other hand, the composite optical sheets of Comparative Examples 11 and 12 containing only the first prism have high adhesion but low luminance. Moire may occur in the composite optical sheet of Comparative Example 13 that does not include the second prism. In the case of Example 9, the microlens array pattern but the luminance was secured similarly to the case of using a prism.

(1) Luminance gain: Measured in the same manner as in Example 1.

(2) Relative luminance: The percentage value (G2 / G1 × 100) of the luminance gain G2 of the sheet of the example or the comparative example was obtained for the luminance gain Gl of the comparative example 12, respectively.

(3) Adhesion: The prepared composite optical sheet was cut into a specimen having a width of 30 mm and a length of 100 mm, and the fracture strength was measured when the composite optical sheet was pulled in a 180 ^° direction at a speed of 100 mm / min using UTM.

(4) Moiré occurrence: It was measured in the same manner as in Example 3 except for the 2012 model 32-inch TV LSJ320HW02.

Claims

[Range of request]

[Claim 11

A first optical sheet including an adhesive layer on one surface; And a second optical sheet formed under the adhesive layer and including an optical pattern on one surface thereof.

The optical pattern includes a plurality of first prisms and a plurality of second prisms lower than the first prism,

The apex of the first prism penetrates the adhesive layer and exists inside the adhesive layer,

A vertex of the second prism penetrates the adhesive layer and exists inside or in contact with the adhesive layer.

[Claim 2]

The thickness (A) of the adhesive layer, the depth (D1) through which the first prism penetrates the adhesive layer, the height (HI) of the first prism and the height (H2) of the second prism satisfy the following formula (1). Composite Optical Sheets:

A> Dl = HI-H2> 0

[Claim 3]

The method of claim 1,

Vertices of the first prism and the second prism penetrate the adhesive layer and exist inside the adhesive layer,

The ratio D1 / D2 of the first penetration depth D1 through which the first prism penetrates the adhesive layer and the second penetration depth D2 through which the second prism penetrates the adhesive layer is about 1.5 to 7 Sheet.

[Claim 4]

The method of claim 3,

The first prism and the second prism have the same vertex angle,

And the pitch of the first prism is greater than the pitch of the second prism.

[Claim 5] The composite optical sheet of claim 1, wherein the first prism and the second prism are alternately arranged.

[Claim 6]

6. The composite optical sheet of claim 5, wherein the first prism and the second prism are arranged with a repetition period.

[Claim 7]

7. The composite optical sheet according to claim 6, wherein the second prism is arranged 2N consecutively (N is an integer of 1 or more), and then the first prism is arranged 2N + 1th.

[Claim 8]

3. The composite optical sheet of claim 2, wherein the ratio of H2 to HI (H1 / H2) is greater than about 1 and less than or equal to 2.

[Claim 9]

The composite optical sheet according to claim 2, wherein the difference H1-H2 between HI and H2 is greater than 0 and less than or equal to about 30 μs.

[Claim 10]

3. The composite optical sheet according to claim 2, wherein the thickness (A) of the adhesive layer is about 1 to 10.

[Claim 11]

The composite optical sheet of claim 1, wherein the vertex angle of the first prism and the vertex angle of the second prism may be the same or different, and each is about 30 ^° to 150 °.

[Claim 12]

The composite optical sheet according to claim 1, wherein the pitch P1 of the first prism and the pitch P2 of the second prism are about 10 to ΙΟΟ ί 皿.

[Claim 13]

13. The composite optical sheet according to claim 12, wherein the ratio (P1 / P2) of the pitch (Ρ2) of the second prism to the pitch (P1) of the first prism is about 1 to 2.

[Claim 14] The composite optical sheet of claim 1, further comprising one or more optical patterns of a micro lens pattern emboss pattern, a lenticular lens pattern, a prism pattern, and a pyramid pattern on the other surface of the first optical sheet.

[Claim 151]

The optical surface of claim 1, wherein at least one optical pattern of a nuclear accidental microlens, a non-nuclear accidental microlens pattern, an embossed pattern, a lenticular lens pattern, a prism pattern, and a pyramid pattern More formed composite optical sheet ᅳ

[Claim 16]

The method of claim 1,

A third prism having a height lower than that of the second prism, the second prism penetrating the adhesive layer;

Vertices of the third prism do not penetrate the adhesive layer,

And a penetration depth of the adhesive layer of the first prism is greater than a penetration depth of the adhesive layer of the second prism.

[Claim 17]

The method of claim 16,

And the second prism and the third prism are arranged at regular intervals between the first prism.

[Claim 18]

The composite optical sheet of claim 17, wherein one or more repetitive patterns including the second prism and the plurality of third prisms are arranged.

[Claim 19]

19. The composite optical sheet of claim 18, wherein the repeating pattern is repeated with a period of 4M, 5M, or 6M, where M is an integer of 1 to 30.

[Claim 20]

19. The method of claim 18, wherein the repeating pattern arranged between the first prism is arranged in a period of 4M 5M, or 6M (where M is an integer of 1 to 30), between the second prism and the second prism and The composite optical sheet, wherein the third prism is arranged between the first prism.

[Claim 21]

17. The composite optical sheet according to claim 16, wherein an adhesion area (S1) between the first prism and the adhesive layer is larger than an adhesion area (S2) between the second prism and the adhesive layer.

[Claim 22]

The composite optical sheet of claim 16, wherein a thickness (A) of the adhesive layer, a height (HI) of the first prism, and a height (H2) of the second prism have a relationship of the following Equation 3:

1> (H1-H2) / A> 0.5.

[Claim 23]

17. The composite optical sheet according to claim 16, wherein a difference (H1-H2) between the height HI of the first prism and the height H2 of the second prism is about 20 / m or less.

[Claim 24]

17. The composite optical sheet according to claim 16, wherein a difference (H2-H3) between the height (H2) of the second prism and the height (H3) of the third prism is about 20 or less.

[Claim 25]

A light source unit;

A light guide plate formed on the light source unit;

The composite optical sheet of any one of claims 1 to 24 formed on the light guide plate; And

And a liquid crystal display panel formed on the composite optical sheet.