KR20100061356A - Complex optical film - Google Patents

Abstract

PURPOSE: A complex optical film is provided to improve luminance and light transmission rate by executing various functions in one complex film. CONSTITUTION: A material(110) physically supports a complex optical film(100). The material comprises the material of Polycarbonate series, Polysulfone series, Polyacrylate series, Polystyrene series, Polyvinylchloride series, Polyvinyl alcohol series, Polynorbornene series, Polyester series. A lower pattern layer(150) is formed in the lower part of the materials. The lower pattern layer prevents the close adhesion of the complex optical film. A cholesteric liquid crystal layer(120) is formed in the upper side of the materials. A phase difference film(130) is laminated on the liquid crystal layer. An upper pattern layer(160) is formed on the phase difference film.

Description

Compound Optical Film

The present invention relates to a composite optical film, and more particularly to a composite optical film applied to the display.

A liquid crystal display (LCD) is a device that displays an image by injecting a liquid crystal between two glass plates and applying power to the upper and lower glass plate electrodes to change the liquid crystal molecular array in each pixel. Unlike a cathode ray tube (CRT), a plasma display panel (PDP), and the like, a display by a liquid crystal display is not light-emitting because it is non-luminous in itself. To compensate for these disadvantages, a light source assembly uniformly irradiated on the information display surface is mounted for the purpose of enabling use in a dark place.

The light source assembly used in the liquid crystal display device is largely classified into two types. The first is an edge type light source assembly that provides light at the side of the liquid crystal display, and the second is a direct type light source assembly that provides light directly at the rear of the liquid crystal display. In the case of the edge type light source assembly, a light guide plate is provided to allow the light emitted from the light source to be irradiated upward, and at least one optical film is disposed above the light guide plate to adjust optical characteristics of light passing through the light guide plate. In the case of the direct type light source assembly, a diffuser plate is provided to reduce bright lines of light emitted from the light source, and at least one optical film is provided to adjust optical characteristics of light passing through the diffuser plate. Some liquid crystal display devices have a liquid crystal film as one of the optical films to improve the brightness.

However, when a plurality of optical films are laminated to form a light source assembly, the thickness thereof increases and the luminance decreases.

The present invention has been conceived based on these points, and the problem to be solved by the present invention is to provide a composite optical film having improved optical transmittance by having various optical functions.

Another object of the present invention is to provide a light source assembly with improved light transmittance.

Another object of the present invention is to provide a liquid crystal display device having improved luminance.

The composite optical film according to an embodiment of the present invention for solving the above problems is a substrate, a lower pattern layer formed on the lower surface of the substrate, a cholesteric liquid crystal layer formed on the upper surface of the substrate, a phase difference film laminated on the liquid crystal layer And an upper pattern layer formed on the retardation film.

The composite optical film according to another embodiment of the present invention for solving the above problems is a substrate, a lower pattern layer formed on the lower surface of the substrate, a cholesteric liquid crystal layer formed on the upper surface of the substrate, color compensation laminated on the liquid crystal layer And a film, a retardation film laminated on the color compensation film, and an upper pattern layer formed on the retardation film.

The composite optical film according to another embodiment of the present invention for solving the above problems is a substrate, a lower pattern layer formed on the lower surface of the substrate, a cholesteric liquid crystal layer formed on the upper surface of the substrate, the phase difference laminated on the liquid crystal layer A film, a color compensation film laminated on the retardation film, and an upper pattern layer formed on the color compensation film.

The light source assembly according to an embodiment of the present invention for solving the other problems includes a composite optical film as described above.

The liquid crystal display according to the exemplary embodiment of the present invention for solving the another problem includes the composite optical film as described above.

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

According to embodiments of the present invention has at least the following effects.

That is, the composite optical film according to an embodiment of the present invention performs various optical functions such as circularly polarized light, reflection, linearly polarized light, diffusion, light mixing, and light condensing in one film. Therefore, thinning of the film can be realized, and light transmittance can be improved. That is, since various functions are implemented in one composite film, brightness may be improved, thickness of the light source assembly may be reduced, and light transmittance may be improved. Furthermore, in the case of a liquid crystal display device employing such a composite optical film, there is an effect of improving the brightness.

The effects according to the present invention are not limited by the contents exemplified above, and more various effects are included in the present specification.

Advantages and features of the present invention and methods for achieving them will be apparent with reference to the embodiments described below in detail with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various forms, and only the present embodiments are intended to complete the disclosure of the present invention, and the general knowledge in the art to which the present invention pertains. It is provided to fully convey the scope of the invention to those skilled in the art, and the present invention is defined only by the scope of the claims.

Hereinafter, with reference to the accompanying drawings will be described embodiments of the present invention.

1 is a cross-sectional view of a composite optical film according to an embodiment of the present invention.

Referring to FIG. 1, the composite optical film 100 according to an exemplary embodiment of the present invention may include a substrate 110, a lower pattern layer 150, a cholesteric liquid crystal layer 120, a retardation film 130, and an upper pattern. Layer 160.

The substrate 110 serves to physically support the entire composite optical film 100. Substrate 110 is a transparent material that can transmit light, for example, polycarbonate (poly carbonate), poly sulfone (poly sulfone), poly acrylate (poly acrylate), poly styrene (poly styrene), polyvinyl It may include a chloride (poly vinyl chloride), poly vinyl alcohol (poly vinyl alcohol), poly norbornene (poly norbornene), polyester (poly ester) material. For example, the substrate 110 may be made of polyethylene terephtalate, polyethylene naphthalate, or the like.

In some embodiments substrate 110 is applied in the form of a rectangular plate. The thickness of the substrate 110 may be, for example, about 10 to 1000 μm, and more specifically 25 to 600 μm. However, of course, the thickness of the substrate 110 is not limited to the above examples.

The lower pattern layer 150 is formed on the bottom surface of the substrate 110. The lower pattern layer 150 serves to prevent adhesion when the composite optical film 100 is laminated to a light guide, a diffusion plate, or another optical film. That is, the lower pattern layer 150 is close to or in close contact with another neighboring optical sheet (not shown), an optical plate (not shown), or a liquid crystal panel (not shown), thereby generating static electricity or friction caused by flow. In this case, scratches are prevented from occurring on the lower surface of the substrate 110 and / or other adjacent optical sheets, optical plates, liquid crystal panels, and the like. In addition, the lower pattern layer 150 itself may serve as diffusion.

2A-2E illustrate examples of lower pattern layers in accordance with various embodiments of the present invention.

First, referring to FIG. 2A, the lower pattern layer 150 may be formed of an embossed pattern 151. Each embossed pattern 151 is independently formed in an island shape, and neighboring embossed patterns 151 are spaced apart from each other by a predetermined interval.

The embossed pattern 151 may have a three-dimensional shape whose cross section is semicircle, trapezoid, or triangle. However, other shapes such as amorphous are also possible. The width of the surface where the embossed pattern 151 is in contact with the bottom surface of the substrate 110 is defined as the diameter of the embossed pattern 151, and the distance at which the embossed pattern 151 protrudes from the bottom surface of the substrate 110 is determined by the embossed pattern. When defined by the height, the diameter of the embossed pattern 151 may be about 0.1 μm to 100 μm, and the height of the embossed pattern 151 may be about 0.05 μm to 50 μm.

On the other hand, if the height of the embossed pattern is too large than the diameter of the embossed pattern 151, there is a problem in stability of the embossed pattern 151 itself, and if the diameter of the embossed pattern 151 is too large compared to the height of the embossed pattern 151, it is unnecessary. In other words, the area occupied by the embossed pattern 151 with respect to the entire area of the substrate 110 is widened, and the light transmission characteristic is disadvantageous. Considering these points, the ratio of the diameter of the embossed pattern 151 and the height of the embossed pattern 151 may be adjusted in the range of about 10: 1 to 1:10.

In some embodiments, the plurality of embossed patterns 151 may be arranged at equal intervals at the positions of certain matrices. In some other embodiments of the present invention, the plurality of embossed patterns 151 may be randomly arranged.

However, if the spacing of the embossing pattern 151 is too large, the possibility that the upper surface of the adjacent optical sheet and the substrate 110 of the compound optical film 100 is in close contact increases, so that the maximum spacing of the neighboring embossing pattern 151 is about It is preferable that it is 1000 micrometers or less. In addition, if the interval between the embossed patterns 151 is too narrow, the number of embossed patterns 151 per unit area increases, and thus the area occupied by the embossed patterns 151 becomes wider, so that light transmission characteristics are disadvantageous. Therefore, the minimum spacing of the embossed pattern 151 is preferably about 1 μm or more.

In addition, when considering the light transmission characteristics, the area occupied by the embossed pattern 151 is preferably adjusted in the range of 0.001% to 95% of the area of the entire substrate 110, more preferably in the range of 0.01% to 10% It is better to adjust at. Here, the occupied area of the embossed pattern 151 may be adjusted by the diameter of each embossed pattern 151, the number of embossed patterns 151, the spacing of the embossed patterns 151, the density of the embossed pattern 151, and the like. Of course.

On the other hand, in consideration of both the semi-adhesiveness and the light transmission characteristics, the average spacing between the neighboring embossing pattern 151 may be, for example, about 5㎛ to 500㎛.

The embossing pattern 151 may be made of a transparent material, and may be advantageous in terms of light transmittance of the composite optical film 100. The embossing pattern 151 may be made of a material having the same or similar hardness as other adjacent optical sheets, optical plates, or liquid crystal panels in order to reduce scratching of other adjacent optical sheets, optical plates, liquid crystal panels, and the like. Here, having similar hardness includes, for example, a case where the difference in MOS hardness is within 1 range. Within such a range of similar hardness, the scratch can be minimized even when the tip of the embossed pattern 151 contacts another adjacent optical sheet, optical plate, liquid crystal panel, or the like.

In some other embodiments, the embossed pattern 151 may be made of a material having a lower hardness than other adjacent optical sheets, optical plates, and liquid crystal panels. For example, the case where the compound optical film 100 is adjacent to another optical sheet is described. When the embossed pattern 151 of the compound optical film 100 has a lower hardness than other adjacent optical sheets, both films / sheets Even if mutual friction occurs, the contact surface of the embossed pattern 151 may be ground, but the surface of another adjacent optical sheet hardly scratches. Until the embossed pattern 151 is ground and all removed, the surface of the substrate 110 of the composite optical film 100 continues to be protected from scratches. In view of the above, the embossed pattern 151 may be made of a material having a MOS hardness of at least 1, preferably at least 1.5, and more preferably at least 2.0, lower than the adjacent optical sheets.

In some embodiments, the embossed pattern 151 may include a material having a friction coefficient of 0.35 or less. If the friction coefficient of the embossing pattern 151 is 0.35 or less, even if the tip of the embossing pattern 151 comes into contact with another adjacent optical sheet, optical plate, liquid crystal panel, or the like, when pressure is applied from the outside, it easily slips on the contact surface. Therefore, the occurrence of scratches can be minimized. As an example of satisfying the condition of the friction coefficient, the embossed pattern 151 may include a UV curable material and an additive.

Examples of applicable UV curable materials include reactive oligomers such as acrylics, urethanes, polyesters, silicones, esters, and the like, and monofunctional (meth) acrylate monomers or polyfunctional (di, tri) (meth) acrylate monomers. do. As said monofunctional (meth) acrylate or polyfunctional (meth) acrylate monomer, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, tetrahydrofurfuryl (meth), for example Acrylate, butoxy ethyl (meth) acrylate, ethyl diethylene glycol (meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, phenoxyethyl (meth) acrylate, di Cyclopentadiene (meth) acrylate, polyethylene glycol (meth) acrylate, polypropylene glycol (meth) acrylate, methyl triethylene diglycol (meth) acrylate, isobornyl (meth) acrylate, N-vinylpyrroli Don, N-vinyl caprolactam, diacetone acrylamide, isobutoxymethyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, t-octyl (meth) acrylamide, di Methylaminoethyl (meth) acrylate, acryloylmorpholine, dicyclopentenyl (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) ) Acrylate, ethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, 1,4-butanedioldi (meth) acrylate, 1,6-hexanediol Di (meth) acrylate, neopentyl glycol di (meth) acrylate, trimethylolpropane trioxyethyl (meth) acrylate, tricyclodecane dimethanol di (meth) acrylate, dicyclodecane dimethanol di (meth) Acrylate, tripropylene glycol di (meth) acrylate, dicyclopentanedi (meth) acrylate, dicyclopentadienedi (meth) acrylate, and the like, It may be used alone or in mixture of the listed substances.

As the additive, a material having high lubricity may be applied. For example, at least one of a silicon based additive and a fluorine based additive may be applied. Specifically, a reactive monomer or a reactive oligomer having a silicone group (for example, a silicone group-containing vinyl compound, a silicone group-containing (meth) acrylate compound, a (meth) acryloxy group-containing organosiloxane, silicone polyacrylate) Etc.), a reactive monomer or reactive oligomer having a fluorine group (e.g., a fluoroalkyl group-containing vinyl compound, a fluoroalkyl group-containing (meth) acrylate compound, fluorine polyacrylate, etc.), a silicone group or a fluorine group A resin (for example, polydimethylsiloxane, fluoropolymer, etc.), a surfactant having a silicone group or a fluorine group, or an oil (for example, dimethyl silicone oil, etc.) may be applied alone or in combination.

The content ratio of the UV curable material and the additive may range from 100 parts by weight: 0.001 parts by weight to 100 parts by weight: 10 parts by weight, preferably 100 parts by weight: 0.01 parts by weight to 100 parts by weight: 5 parts by weight. .

The embossing pattern 151 may further include a photoinitiator in addition to the UV curable material and the additive. The photoinitiator is one or more free radical initiators selected from benzyl ketals, benzoin ethers, acetophenone derivatives, ketoxime ethers, benzophenones, benzo or thioxanthone compounds, onium salts, ferrocenium salts ( ferrocenium salts, and one or more cationic initiators selected from diazonium salts, or mixtures thereof.

When a plurality of embossed patterns 151 having a suitable height are disposed at appropriate intervals on the lower surface of the substrate 110, even if the upper surface of another neighboring optical sheet is flat, the optical sheet and the composite optical film 100 are embossed patterns. Only in contact with 151, the upper surface of the optical sheet and the substrate 110 is not directly in contact, and is spaced a predetermined distance apart. Therefore, although the neighboring optical sheet and the composite optical film 100 are sequentially laminated, the whole surface is not in close contact. As a result, static electricity between the neighboring optical sheet and the composite optical film 100 can be prevented, and scratches on the surface of the substrate 110 of the composite optical film 100 can be prevented.

Another example applicable to the lower pattern layer 150 is an adhesion preventing layer 152 that includes an embossed surface as shown in FIG. 2B. The adhesion preventing layer 152 includes a base layer 152a having a predetermined thickness and an emboss shape 152b protruding from the surface of the base layer 152a. The emboss shape 152b is substantially identical in configuration and arrangement to the emboss pattern 151 of FIG. 2A.

2C-2F illustrate the lower pattern layer 150 using beads. 2C to 2F, a plurality of beads 154 may be formed on the lower surface of the substrate 110 instead of the embossed pattern 151 of FIG. 2A. Bead 154 may include, for example, at least one of organic beads and inorganic beads. Examples of the organic beads include homopolymers or copolymers obtained by using monomers such as acrylic, styrene, melamine formaldehyde, propylene, ethylene, silicone, urethane, methyl (meth) acrylate, polycarbonate, and the like. Examples of the inorganic beads include silica, zirconia, calcium carbonate, barium sulfate, titanium oxide, and the like. Since the beads 154 replace the role of the embossed pattern 151, the shape or arrangement of the beads 154 is substantially the same as that of the embossed pattern 151 described above.

In some embodiments, the plurality of beads 154 are supported on the substrate 110 by a support coating film 153. The support coating film 153 is formed on the bottom surface of the substrate 110 to at least partially surround the beads 154. For example, the support coating film 153 is formed to surround the entire bead 154, as shown in FIG. 2C, or only covers a portion of the bead 154, as shown in FIG. 2D, Some may be formed to be exposed. In addition, the support coating film 153 may be formed in a pattern shape to surround the bead 154, as shown in Figure 2e.

The support coating film 153 may be, for example, a thermosetting resin such as an acrylic resin, a urethane resin or a polyester resin, or an epoxy acrylate resin, a urethane arctic resin, a silicone acrylate resin, an acrylic acrylate or an ester acrylate. UV curable resins, such as the like.

In some embodiments, the plurality of beads 154 may have various different sizes, as shown in FIG. 2F.

Referring back to FIG. 1, the cholesteric liquid crystal layer 120 is formed on the upper surface of the substrate 110. In the drawing, the cholesteric liquid crystal layer 120 is formed directly on the upper surface of the substrate 110, but the cholesteric liquid crystal layer 120 may be stacked on the upper surface of the substrate 110 through an adhesive layer. .

The cholesteric liquid crystal layer 120 performs a function of selectively reflecting circularly polarized light. Cholesteric liquid crystals (or chiral nematic liquid crystals). The cholesteric liquid crystal may include a nematic liquid crystal and a chiral dopant. Cholesteric liquid crystals have a constant pitch and have a spiral structure twisted repeatedly. Repeated twisted helical structure induces Bragg reflection of light.

Cholesteric liquid crystals are classified into right-handed cholesteric liquid crystals and left-handed cholesteric liquid crystals according to their spiral directions. Preferred cholesteric liquid crystals reflect right polarized light but transmit left polarized light. In contrast, the left cholesteric liquid crystal transmits right polarized light but reflects left circular polarized light. Therefore, in theory, the cholesteric liquid crystal transmits 50% of the light included in the wavelength range reflected by the cholesteric liquid crystal and reflects the remaining 50%.

The pitch (liquid crystal pitch) of the cholesteric liquid crystal is related to the wavelength of the reflected light. The central wavelength of the reflected light reflected by the cholesteric liquid crystal is generally proportional to the liquid crystal pitch. Here, when the reflected light reflected by the cholesteric liquid crystal has a predetermined band width, the center wavelength of the reflected light may mean a wavelength that is maximum reflected within the band width or an average wavelength of the band width. In addition, the bandwidth of the reflected light may mean a range of wavelengths capable of reflecting about 30% to about 70% of the incident light, preferably reflecting about 40% to about 60% of the incident light The range of wavelengths that can be used may mean a range of wavelengths that can more preferably reflect about 50% of incident light.

The cholesteric liquid crystal layer 120 may be formed of a single layer, and may include a plurality of liquid crystal pitch regions having different pitches of the cholesteric liquid crystal in the film. In general, a larger liquid crystal pitch reflects light having a longer wavelength, and a smaller liquid crystal pitch reflects light having a relatively shorter wavelength. Therefore, as the cholesteric liquid crystal layer 120 includes more various liquid crystal pitch regions, its reflection band increases. In order for the cholesteric liquid crystal layer 120 of the single layer to form sufficiently various liquid crystal pitch regions, the thickness of the cholesteric liquid crystal layer 120 may be about 1 to 100 μm. More preferably in the range of about 2-15 μm.

In some preferred embodiments, the central wavelength of reflected light of the maximum liquid crystal pitch region of the cholesteric liquid crystal layer 120 is greater than or equal to the red light wavelength (eg, about 650 nm to 780 nm) in the single layer, and the central wavelength of reflected light of the minimum liquid crystal pitch region is Below the blue light wavelength (e.g., 380 nm to 520 nm), the central wavelengths of reflected light in the liquid crystal pitch regions are distributed in the wavelengths of the green light (e.g., 520 nm to 650 nm), respectively, to reflect the entire visible light region.

3 is a graph illustrating a liquid crystal pitch of a cholesteric liquid crystal layer according to some embodiments of the present invention. Referring to FIG. 3, while changing in the thickness direction in a single layer, the liquid crystal pitch may increase and then decrease. That is, the reflection band according to the liquid crystal pitch is changed in the order of G, R, G, B from the base surface. It has been experimentally confirmed that this pitch arrangement improves the Off Axis Color (OAC) characteristic of the exit face side. More details on this are disclosed in Korean Patent Application No. 10-2009-0082057 filed by the applicant, which is incorporated by reference as if fully described herein.

On the other hand, although the case where the cholesteric liquid crystal layer 120 has a reflectance of about 30% to about 70% with respect to the full-wavelength range of visible light has been discussed, the present invention is not limited thereto, and some wavelengths of visible light, Or it may be adjusted to have a reflectance for light of other wavelengths, such as infrared rays, ultraviolet rays, X-rays, or high frequency, medium frequency, low frequency electromagnetic waves, and the like. In addition, the reflectance is not limited to the above range, and it is apparent that other various reflectances may be employed.

Referring back to FIG. 1, an adhesive layer 190 is formed on the cholesteric liquid crystal layer 120, and a retardation film 130 is formed thereon. The retardation film 130 may be, for example, a λ / 4 retardation film 130 that delays a phase of light by λ / 4. When circularly polarized light transmitted through the cholesteric liquid crystal layer 120 passes through the λ / 4 retardation film 130, it is converted into linearly polarized light.

The retardation film 130 may be manufactured by, for example, monoaxially or biaxially stretching a transparent film such as polycarbonate, cellulose resin, or cyclic olefin resin.

The upper pattern layer 160 is formed on the retardation film 130. The upper pattern layer 160 collects, diffuses, or mixes the light emitted at various angles through the composite optical film 100. In particular, when the upper pattern layer 160 performs a function of mixing light, the off-axis color may be further improved. In addition, when the cholesteric liquid crystal layer 120 having the above-described GRGB liquid crystal pitch gradation is used in combination, a significant off-axis color improvement effect may be exhibited even without a separate color correction film.

In the drawing, an example in which the upper pattern layer 160 is directly formed on the retardation film 130 is illustrated, but the upper pattern layer 160 may be stacked on the retardation film 130 via an adhesive layer.

4A-4C illustrate an example of an upper pattern layer in accordance with various embodiments of the present invention.

Referring to FIG. 4A, the upper pattern layer may include a plurality of diffusion beads 161 supported by the support coating layer 162. In this case, the upper pattern layer 160 serves to diffuse light. The support coating film 162 and the diffusion beads 161 may be similar in structure and material to the support coating film 153 and the beads 154 described as an example of constituting the lower pattern layer 150 described above. Thus, although not shown, the support coating layer 162 and the diffusion beads 161 may have a pattern similar to the pattern of FIGS. 2C to 2E.

However, the size of the diffusion bead 161 may be larger than the size of the bead 154 of the lower pattern layer 150. For example, the size of the diffusion beads 161 of the upper pattern layer 160 may range from 1.5 to 20 times the size of the beads 154 of the lower pattern layer 150. In addition, in order to exhibit a sufficient diffusion effect, the content of the diffusion beads 161 of the upper pattern layer 160 may be larger than the lower pattern layer 150. For example, it may be selected in the range of 2 to 50 times.

4B illustrates that a diffusion lens 166 for light diffusion is used as the upper pattern layer 160. The diffusion lens 166 may be a hemispherical lens or micro lens of an island pattern or a lenticular lens of a line pattern. In addition to the convex shape shown, a concave lens can also be used.

4C illustrates that the prism structure 167 for condensing is formed as the upper pattern layer 160. The prism structure 167 may be, for example, a square pyramidal or triangular pyramidal shape in an island pattern or a mountain structure in a line pattern.

Although not shown, in some embodiments, the upper pattern layer 160 and the lower pattern layer 150 may have substantially the same structure.

The various lower pattern layers 150 and the upper pattern layers 160 described above may be variously combined with each other.

As such, the composite optical film 100 according to an embodiment of the present invention performs various optical functions such as circularly polarized light, reflection, linearly polarized light, diffusion, light mixing, and light condensing in one film. Therefore, thinning of the film can be realized, and light transmittance can be improved. In addition, if the liquid crystal pitch structure of the cholesteric liquid crystal layer 120 is adopted as a GRGB gradation structure, and the light mixing function is provided to the upper pattern layer 160, a color correction film may be omitted even if the color correction film is omitted. There is an improvement effect. If the color correction film is omitted, the adhesive layer 190 accompanying them may be omitted together, and thus the light transmittance may be remarkably improved.

5 is a cross-sectional view of a composite optical film according to another embodiment of the present invention. Referring to FIG. 5, in the composite optical film 101 according to the present exemplary embodiment, except that a color compensation film 140 is interposed between the cholesteric liquid crystal layer 120 and the retardation film 130, FIG. It is substantially the same as the embodiment of. In the present embodiment, that is, the color compensation film 140 is laminated on the cholesteric liquid crystal layer 120 via the adhesive layer 190, and the retardation film 130 is disposed on the color compensation film (through the adhesive layer 190). 140). Compared to the embodiment of FIG. 1, the present embodiment slightly sacrifices light transmittance as the color compensation film 140 and the additional adhesive layer 190 are used, but the color compensation effect and the off-axis color are improved.

6 is a cross-sectional view of a composite optical film 102 according to another embodiment of the present invention. Referring to FIG. 6, the composite optical film 100 according to the present exemplary embodiment is substantially the same as the exemplary embodiment of FIG. 5 except that the retardation film 130 and the color compensation film 140 are reversed. In this embodiment, that is, the retardation film 130 is laminated on the cholesteric liquid crystal layer 120 via the adhesive layer 190, and the color compensation film 140 is interposed with the retardation film 130 through the adhesive layer 190. It is laminated on). In addition, the upper pattern layer 160 is formed on the color compensation film 140. In the case of the present embodiment, the light transmittance is slightly sacrificed as the color compensation film 140 and the additional adhesive layer 190 are used, but the color compensation effect and the off-axis color are improved.

The composite optical films 100-102 according to the embodiments of the present invention described above may be employed to improve light efficiency by being employed in a light source assembly or a liquid crystal display including the same. The light source assembly is classified into a direct type light source assembly in which the lamp is located at the bottom, and an edge type light source assembly in which the lamp is located at the side, and the like. The composite optical film 100-102 according to embodiments of the present invention may be any kind of light source. It is also possible to adopt the assembly. The present invention is also applicable to a back light assembly disposed below the liquid crystal panel or a front light assembly disposed above the liquid crystal panel. Hereinafter, as an example of various application examples, the composite optical film 100-102 according to an embodiment of the present invention is applied to a liquid crystal display including a direct backlight assembly.

7 is a cross-sectional view of a liquid crystal display according to an exemplary embodiment of the present invention.

Referring to FIG. 7, the liquid crystal display 600 includes a backlight assembly 300, a liquid crystal panel assembly 400, and a top chassis 500.

The backlight assembly 300 includes a lamp 310, a reflective film 315 that reflects light emitted from the lamp 310, and a diffuser plate 320 and optical films 330 that adjust optical characteristics of the emitted light. It includes.

Lamp 310 may be used, for example, Cold Cathode Fluorescent Lamp (CCFL), Hot Cathode Fluorescent Lamp (HCFL), External Electrode Fluorescent Lamp (EEFL).

A reflective film 315 is disposed below the lamp 310 to reflect light emitted downward from the lamp 310 upward.

The diffusion plate 320 and the optical films 230 are disposed on the lamp 310. The diffusion plate 320 diffuses the light incident from the lamp 310. Optical films 330 may include a composite optical film 100-102 in accordance with embodiments of the present invention, and optionally, a diffuser film, a prism sheet, a reflective polarizer, a retardation film, and / or a protective film. Can be.

The lamp 310, the reflective film 315, the diffuser plate 320, and the optical films 330 are received by the bottom chassis 340 and the mold frame 350. The bottom chassis 340 forms the bottom surface of the backlight assembly 300, and a mold frame 350 having a window frame shape is disposed on the bottom chassis 340, and the light diffuser plate is disposed at a seating end provided in the mold frame 350. 320, the optical films 330 and the liquid crystal panel 410 are seated.

The liquid crystal panel assembly 400 includes a liquid crystal panel 410 including a first display panel 411, a second display panel 412, and a liquid crystal layer (not shown) interposed therebetween, the first display panel 411, and the second display panel 411. The polarizing plate 420 attached to the surface of the display panel 412, the data TCP (Tape Carrier Package) 430 attached to one side of the liquid crystal panel 310, and the printed circuit board 440 attached to the data TCP 430. ). On the data TCP 430, a data driver integrated circuit (IC) 431 is mounted. A gate TCP (not shown) is attached to the other side of the liquid crystal panel 410 adjacent to the attachment side of the data TCP 430, and a gate driver IC (not shown) is mounted on the gate TCP.

The top chassis 500 covers an edge of the liquid crystal panel 410 and surrounds side surfaces of the liquid crystal panel 410 and the backlight assembly 300. The data TCP 430, the printed circuit board 440, and the like are bent and received in a space between the side wall of the bottom chassis 340 and the side wall of the top chassis 500.

Although the embodiments of the present invention have been described above with reference to the accompanying drawings, those skilled in the art to which the present invention pertains may be embodied in other specific forms without changing the technical spirit or essential features of the present invention. I can understand that. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive.

1 is a cross-sectional view of a composite optical film according to an embodiment of the present invention.

2A through 2E are cross-sectional views illustrating examples of lower pattern layers according to various embodiments of the present disclosure.

3 is a graph illustrating a liquid crystal pitch of a cholesteric liquid crystal layer according to some embodiments of the present invention.

4A through 4C are cross-sectional views illustrating examples of an upper pattern layer according to various embodiments of the present disclosure.

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

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

7 is a cross-sectional view of a liquid crystal display according to an exemplary embodiment of the present invention.

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

110: base material 120: cholesteric liquid crystal layer

130: retardation film 140: color compensation film

150: lower pattern layer 160: upper pattern layer

190: adhesive layer

Claims (12)

materials; A lower pattern layer formed on the bottom surface of the substrate; A cholesteric liquid crystal layer formed on the upper surface of the substrate; A retardation film laminated on the liquid crystal layer; And Composite optical film comprising an upper pattern layer formed on the retardation film. According to claim 1, The retardation film is a composite optical film laminated on the cholesteric liquid crystal layer via an adhesive layer. materials; A lower pattern layer formed on the bottom surface of the substrate; A cholesteric liquid crystal layer formed on the upper surface of the substrate; A color compensation film laminated on the liquid crystal layer; A retardation film laminated on the color compensation film; And Composite optical film comprising an upper pattern layer formed on the retardation film. The method of claim 3, The color compensation film is laminated on the cholesteric liquid crystal layer via a first adhesive layer, The retardation film is a composite optical film laminated on the retardation film via a second adhesive layer. materials; A lower pattern layer formed on the bottom surface of the substrate; A cholesteric liquid crystal layer formed on the upper surface of the substrate; A retardation film laminated on the liquid crystal layer; A color compensation film laminated on the retardation film; And Composite optical film comprising an upper pattern layer formed on the color compensation film. 6. The method of claim 5, The retardation film is laminated on the cholesteric liquid crystal layer via a first adhesive layer, The color compensation film is a composite optical film laminated on the retardation film via a second adhesive layer. The method according to any one of claims 1 to 6, The cholesteric liquid crystal layer is a composite optical film including a plurality of liquid crystal pitch region. The method according to any one of claims 1 to 6, In the cholesteric liquid crystal layer, the liquid crystal pitch increases in the thickness direction from the base surface and then decreases. The reflection band according to each liquid crystal pitch changes in order of green light reflection band, red light reflection band, green light reflection band, and blue light reflection band from a base surface to thickness direction. The method according to any one of claims 1 to 6, The lower pattern layer may include an embossed pattern, an adhesion preventing layer including an embossed surface, or a plurality of beads. The method according to any one of claims 1 to 6, The upper pattern layer is a composite optical film comprising a plurality of diffusion beads, diffusion lenses, or prism structures. A light source assembly comprising the composite optical film according to claim 1. A liquid crystal display device comprising the composite optical film according to any one of claims 1 to 6.

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