KR102225056B1 - Curved liquid crystal display device - Google Patents

Abstract

The present invention relates to a curved liquid crystal display device capable of improving the degree of immersion.
In the curved liquid crystal display of the present invention, the upper and lower polarizing plates are attached to the liquid crystal panel using a hard-type adhesive layer, and light leakage is prevented by annealing in a curved state or by attaching a polarizing plate in a curved state to manufacture a curved liquid crystal display. can do.

Description

Curved liquid crystal display device

The present invention relates to a liquid crystal display device, and more particularly, to a curved liquid crystal display device.

As the information society develops, demands for display devices for displaying images are increasing in various forms, and liquid crystal display devices (LCD devices), plasma display panel devices (PDP devices), Various flat panel display devices (FPD devices) such as organic light emitting diode devices (OLED devices) have been widely developed and applied to various fields.

Among these flat panel display devices, liquid crystal display devices are widely used because they have advantages such as miniaturization, weight reduction, thinness, and low power driving.

In general, a liquid crystal display device uses optical anisotropy and polarization properties of a liquid crystal, and includes a liquid crystal layer between two substrates and a liquid crystal layer, and a pixel electrode and a common electrode for driving liquid crystal molecules of the liquid crystal layer. Accordingly, in the liquid crystal display device, the liquid crystal molecules move by an electric field generated by applying a voltage to a pixel electrode and a common electrode, thereby expressing an image by a transmittance of light that varies accordingly. Such liquid crystal display devices are applied in various ways from portable devices such as mobile phones and multimedia devices to notebook computers or computer monitors and large televisions.

However, a liquid crystal display device as a flat panel display device has a problem in that a distance deviation from the main viewing area of the viewer to the display screen occurs depending on the location.

This will be described with reference to FIG. 1.

1 is a schematic diagram of a general liquid crystal display device.

As shown in Fig. 1, since the liquid crystal display 10 is manufactured in a flat plate shape, the first distance d1 from the main viewing area of the viewer to the center area of the liquid crystal display 10 and the liquid crystal from the main viewing area The second distance d2 to the left and right regions of the display device 10 is different from each other. That is, the second distance d2 is greater than the first distance d1, and a distance deviation from the main viewing area to the display screen of the liquid crystal display 10 occurs.

The problem of such distance deviation appears larger as the screen of the liquid crystal display 10 increases, and thus, the degree of immersion in the image displayed through the liquid crystal display 10 decreases.

The present invention has been presented to solve the above problems, and an object of the present invention is to provide a curved liquid crystal display device capable of solving the distance deviation problem.

In order to achieve the above object, the present invention provides a liquid crystal panel, a first polarizing plate attached to a lower surface of the liquid crystal panel, a first adhesive layer between the liquid crystal panel and the first polarizing plate, and an upper surface of the liquid crystal panel. A second polarizing plate attached to and a second adhesive layer between the liquid crystal panel and the second polarizing plate, wherein the first adhesive layer and the second adhesive layer are of a hard type having an elastic modulus of 100,000 Pa or more. It provides a curved liquid crystal display device.

The curved liquid crystal display of the present invention further includes an auxiliary film attached to an upper portion of the second polarizing plate, and a third adhesive layer between the second polarizing plate and the auxiliary film, and the third adhesive layer is of a hard type.

The auxiliary film is an antistatic layer, a hard coating layer, a low reflection layer, or a patterned retarder.

The present invention provides the steps of preparing a liquid crystal panel, attaching a first polarizing plate to a lower surface of the liquid crystal panel using a first adhesive layer, and a second polarizing plate using a second adhesive layer to the upper surface of the liquid crystal panel. And forming a curved surface on the liquid crystal panel, wherein the first adhesive layer and the second adhesive layer are of a hard type having an elastic modulus of 100,000 Pa or more. Provides.

The forming of the curved surface is performed after attaching the first polarizing plate and attaching the second polarizing plate, and includes annealing the liquid crystal panel to which the first and second polarizing plates are attached.

The forming of the curved surface is performed before attaching the first polarizing plate and the attaching the second polarizing plate, and includes disposing the liquid crystal panel on a stage having a curved upper surface.

Attaching the first polarizing plate includes attaching the first polarizing plate to the liquid crystal panel disposed on a stage having an upper surface of a convex curved shape, and attaching the second polarizing plate includes: And attaching the second polarizing plate to the liquid crystal panel disposed on a stage having a convex curved upper surface.

The manufacturing method of the curved liquid crystal display device of the present invention further includes a step of attaching an auxiliary film using a third adhesive layer on the second polarizing plate, wherein the third adhesive layer is of a hard type.

By providing a curved liquid crystal display device, the present invention can prevent a deviation between the distance from the main viewing area to the central area of the display device and the distance to both areas. Therefore, there is an effect of improving the degree of immersion of the viewer.

In addition, since a curved liquid crystal display device is manufactured by annealing in a curved state or attaching a polarizing plate in a curved state, when the display device in a flat state is artificially bent, a stress applied locally can be removed and light leakage can be prevented.

In addition, by forming both the adhesive layers of the upper and lower polarizing plates in a hard type to maintain the curved state, it is possible to prevent the curved liquid crystal display from being deformed into a flat state and prevent light leakage.

1 is a schematic diagram of a general liquid crystal display device.
2 is a schematic diagram of a curved liquid crystal display according to a first embodiment of the present invention.
3 is a diagram illustrating light leakage generated in the curved liquid crystal display device according to the first embodiment of the present invention.
4 is a schematic cross-sectional view of a curved liquid crystal display according to a first embodiment of the present invention.
5A is a view showing an arrangement of liquid crystal molecules on an inner surface of a first substrate at one corner of a curved liquid crystal display according to the first exemplary embodiment of the present invention, and FIG. 5B is a curved surface according to the first exemplary embodiment of the present invention. It is a view showing the arrangement of liquid crystal molecules on the inner surface of the second substrate at one corner of the liquid crystal display, and FIG. 5C is a view showing the arrangement of liquid crystal molecules of FIGS. 5A and 5B together.
6 is a schematic cross-sectional view of a curved liquid crystal display according to a second embodiment of the present invention.
7 is a cross-sectional view schematically illustrating a liquid crystal panel of a curved liquid crystal display according to a second exemplary embodiment of the present invention, showing one pixel area.
8 is a diagram schematically illustrating an example of a method of forming a curved surface of a curved liquid crystal display according to a second exemplary embodiment of the present invention.
9A and 9B are diagrams schematically showing another example of a method for forming a curved surface of a curved liquid crystal display according to a second exemplary embodiment of the present invention.
10 is a schematic cross-sectional view of a curved liquid crystal display according to a third embodiment of the present invention.
11A to 11C are views schematically showing an example of a method of forming a curved surface of a curved liquid crystal display according to a third exemplary embodiment of the present invention.

Hereinafter, the present invention capable of solving the above problems will be described with reference to the drawings.

-First Example-

2 is a schematic diagram of a curved liquid crystal display according to a first embodiment of the present invention.

As shown in FIG. 2, the curved liquid crystal display 100 according to the first embodiment of the present invention has a curved shape. That is, the flat display device is bent at a constant curvature with respect to the center to form a curved surface.

Accordingly, the first distance d11 from the viewer's main viewing area to the central area of the curved liquid crystal display 100 and the second distance d12 from the main viewing area to the left and right sides of the curved liquid crystal display 100 are Since they are substantially the same, the problem of distance deviation in the conventional flat panel display device is solved and the viewer's immersion is improved.

However, since the curved liquid crystal display 100 according to the first embodiment of the present invention artificially forms a curvature, light leakage occurs at four corners as shown in FIG. 3.

This light leakage will be described with reference to FIGS. 4 and 5A to 5C.

4 is a schematic cross-sectional view of a curved liquid crystal display according to a first embodiment of the present invention. 5A is a view showing an arrangement of liquid crystal molecules on an inner surface of a first substrate at one corner of a curved liquid crystal display according to the first exemplary embodiment of the present invention, and FIG. 5B is a curved surface according to the first exemplary embodiment of the present invention. It is a view showing the arrangement of liquid crystal molecules on the inner surface of the second substrate at one corner of the liquid crystal display, and FIG. 5C is a view showing the arrangement of the liquid crystal molecules of FIGS. 5A and 5B together.

4, the curved liquid crystal display 100 according to the first embodiment of the present invention includes a first substrate 110, a second substrate 120, and first and second substrates 110, 120) and a liquid crystal layer 130 therebetween. A seal pattern 140 for preventing leakage of the liquid crystal layer 130 is formed at an edge between the first and second substrates 110 and 120.

Although not shown, a gate wire and a data wire crossing each other to define a pixel region on the inner surface of the first substrate 110, a thin film transistor connected to the gate wire and data wire, and a pixel electrode formed in the pixel region and connected to the thin film transistor , And a common electrode for generating an electric field is formed together with the pixel electrode. This first substrate 110 is referred to as an array substrate.

Further, although not shown, a black matrix and a color filter layer may be formed on the inner surface of the second substrate 120. The black matrix is positioned corresponding to the gate wiring, the data wiring, and the thin film transistor, has an opening corresponding to the pixel area, and blocks light other than the pixel area. The color filter layer corresponds to the opening of the black matrix and includes red, green, and blue color filters sequentially arranged, and one color filter corresponds to one pixel area. This second substrate 120 is referred to as a color filter substrate.

Meanwhile, first and second alignment layers (not shown) having alignment axes in a predetermined direction are formed on the uppermost layers of the inner surfaces of the first substrate 110 and the second substrate 120, respectively, so that the liquid crystal molecules of the liquid crystal layer 130 are formed. Determine the initial arrangement. Here, the orientation axes of each of the first and second alignment layers are parallel to the direction of the short sides of the substrates 110 and 120.

In addition, a lower polarizing plate and an upper polarizing plate (not shown) are attached to the outer surfaces of the first substrate 110 and the second substrate 120, respectively, and the light transmission axis of the lower polarizing plate is disposed perpendicular to the light transmission axis of the upper polarizing plate. .

The curved liquid crystal display 100 according to the first exemplary embodiment of the present invention is transformed from a planar state to a curved state.

As an example, the curved liquid crystal display device 100 according to the first embodiment of the present invention controls the flat display device along the horizontal direction by artificially applying force in order to implement a curved surface in a horizontal direction, that is, a long side direction. 2 By being bent toward the substrate 120 at a constant curvature, it has a curved shape. By the way, since the edges of the first substrate 110 and the second substrate 120 are bonded to each other by the seal pattern 140, the behavior of the first substrate 110 and the second substrate 120 against bending is different.

That is, in the curved liquid crystal display device 100, a tensile stress is applied to the first substrate 110 on the outside of the bend along the horizontal direction, and the second substrate 120 on the inside that is bent is applied along the horizontal direction. Compressive stress is applied. However, since the edges of the first and second substrates 110 and 120 are fixed by the seal pattern 140, torsional stress is applied to the edges of the first and second substrates 110 and 120. ) Is generated, and the first substrate 110 and the second substrate 120 are shifted in opposite directions.

At this time, the torsional stress is greatest at the four corners of the first substrate 110 and the second substrate 120, and the orientation axes of the first and second alignment layers (not shown) are twisted due to the torsional stress. And the arrangement of liquid crystal molecules adjacent to the inner surfaces of the second substrates 110 and 120 are distorted, and light leakage occurs at four corners.

That is, as the alignment axes of the first and second alignment layers are twisted in opposite directions, the first The liquid crystal molecules 131 located on the inner surface of the substrate (110 in FIG. 4) are rotated clockwise with respect to the initial alignment axis, and as shown in FIG. 5B, the liquid crystal molecules located on the inner surface of the second substrate (120 in FIG. 4) Molecules 132 are rotated counterclockwise with respect to the initial orientation axis.

Accordingly, as shown in FIG. 5C, the liquid crystal molecules 131 located on the inner surface of the first substrate (110 in FIG. 4) and the liquid crystal molecules 132 located on the inner surface of the second substrate (120 in FIG. 4) are at a certain angle. It is twisted and arranged with (θ1).

Light leakage occurs due to the misalignment of the liquid crystal molecules 131 and 132.

On the other hand, by manufacturing a curved liquid crystal display by annealing the liquid crystal display in a flat state for a long time, such initial light leakage can be prevented.

Annealing is a method of making a curved surface using shrinkage by evaporating moisture from a polarizing plate. Here, in order to increase the contraction force of the upper polarizing plate and reduce the contraction force of the lower polarizing plate, the upper polarizing plate is attached using a hard type adhesive and the lower polarizing plate is attached using a soft type adhesive.

However, when the curved liquid crystal display manufactured by the annealing method is left at room temperature for a long time, the polarizing plate absorbs moisture and expands, and the curved liquid crystal display is transformed into a flat state as the polarizing plate is unfolded.

At this time, since the expansion force of the upper polarizing plate is greater than that of the lower polarizing plate, like the contraction force, the curved liquid crystal display is in a flat state, and the first substrate (110 in FIG. 4) and the second substrate (120 in FIG. 4) are At the edge, a torsional stress is generated in the opposite direction from the deformation from a flat state to a curved state.

Due to this torsional stress, the alignment axes of the first and second alignment layers are bent, and the arrangement of liquid crystal molecules adjacent to the inner surfaces of the first substrate (110 in FIG. 4) and the second substrate (120 in FIG. 4) is distorted. Light leakage occurs at the four corners.

-Second Example-

6 is a schematic cross-sectional view of a curved liquid crystal display according to a second embodiment of the present invention, and FIG. 7 is a schematic cross-sectional view of a liquid crystal panel of a curved liquid crystal display according to a second embodiment of the present invention. The pixel area is shown. Here, for convenience, the curved liquid crystal display is shown in a flat form.

6, the curved liquid crystal display 200 according to the second embodiment of the present invention includes a liquid crystal panel 210, which is a display panel, and a first polarizing plate positioned on the first side of the liquid crystal panel 210. 260 and a second polarizing plate 270 positioned on the second side of the liquid crystal panel 210. In addition, the curved liquid crystal display 200 further includes a backlight unit (not shown) positioned under the first polarizing plate 260.

Referring to FIG. 7, the liquid crystal panel 210 includes a first substrate 220, a second substrate 240, and a liquid crystal layer 250 between the first and second substrates 220 and 240.

A gate wiring (not shown), a gate electrode 222, and a common wiring (not shown) are formed on the inner surface of the first substrate 220. The gate wiring extends along the first direction, and the gate electrode 222 is connected to the gate wiring. The gate electrode 222 may extend from the gate wiring or may be a part of the gate wiring. The common wiring extends parallel to the gate wiring along the first direction.

A gate insulating layer 224 is formed on the gate wiring, the gate electrode 222 and the common wiring. The gate insulating layer 224 may be formed of an inorganic insulating material of silicon nitride (SiNx) or silicon oxide (SiO _{2 ).}

A semiconductor layer 226 is formed on the gate insulating layer 224 to correspond to the gate electrode 222. The semiconductor layer 226 includes an active layer 226a of intrinsic amorphous silicon and an ohmic contact layer 226b of impurity-doped amorphous silicon.

The source and drain electrodes 228 and 229 are formed on the semiconductor layer 226, the source and drain electrodes 228 and 229 are spaced apart from the semiconductor layer 226, and the ohmic contact layer 226b is a source And the drain electrodes 228 and 229 have the same shape. The active layer 226a is exposed between the source and drain electrodes 228 and 229, and the active layer 226a is the same as the source and drain electrodes 228 and 229 except between the source and drain electrodes 228 and 229. It can have a shape.

The gate electrode 222, the semiconductor layer 226, the source electrode 228, and the drain electrode 229 form a thin film transistor T, and the active layer 226a exposed between the source and drain electrodes 228 and 229 ) Becomes a channel of the thin film transistor T.

In addition, data wiring (not shown) is formed of the same material on the same layer as the source and drain electrodes 228 and 229. The data line extends in a second direction perpendicular to the first direction, and crosses the gate line to define a pixel region. The data line is connected to the source electrode 228, and a dummy semiconductor pattern having the same structure as the semiconductor layer 226 may be formed under the data line.

A first protective layer 230 is formed on the source and drain electrodes 228 and 229 and the data line. The first protective layer 230 may be formed of an inorganic insulating material of silicon _{oxide (SiO 2) or silicon nitride (SiNx).}

A second protective layer 232 is formed on the first protective layer 230. The second protective layer 232 has a flat surface and has a drain contact hole 232a exposing the drain electrode 229 together with the first protective layer 230. The second protective layer 232 may be formed of an organic insulating material such as benzocyclobutene (BCB) or photo acryl.

Here, one of the first protective layer 230 and the second protective layer 232 may be omitted.

A pixel electrode 234 and a common electrode 236 are formed in the pixel region above the second protective layer 232. The pixel electrode 234 contacts the drain electrode 229 through the drain contact hole 232a. The common electrodes 236 contact the common wiring and are alternately disposed to be spaced apart from the pixel electrode 234. The pixel electrode 234 and the common electrode 236 may be formed of a transparent conductive material such as indium tin oxide or indium zinc oxide.

A black matrix 242 is formed on the inner surface of the second substrate 240. The black matrix 242 has an opening corresponding to a pixel region, and may be formed to correspond to a gate line (not shown), a data line (not shown), and the thin film transistor T.

A color filter layer 244 is formed under the black matrix 242 to correspond to the opening of the black matrix 242. The color filter layer 244 includes red, green, and blue color filters, and one color filter is sequentially and repeatedly arranged in correspondence with one pixel area.

Here, a structure in which the color filter layer 244 is formed on the second substrate 240 has been described, but the color filter layer may be formed on the first substrate 220. That is, in the curved liquid crystal display 200 according to the second embodiment of the present invention, a color filter on TFT (COT) in which a color filter layer is formed on the thin film transistor T on the first substrate 220 ) Can have a structure.

This COT structure can increase the aperture ratio by reducing the bonding margin of the first and second substrates 220 and 240. In this case, the black matrix may be omitted, and if the black matrix is omitted, the aperture ratio may be further increased.

An overcoat layer (not shown) may be formed under the color filter layer 244 to protect and planarize the color filter layer 244.

Meanwhile, although not shown, a first alignment layer is formed on the pixel electrode 234 and the common electrode 236 of the first substrate 220, and a second alignment layer is formed under the color filter layer 244 of the second substrate 240. Is formed. The first alignment layer and the second alignment layer are rubbed or photo-aligned in a predetermined direction, so that the surfaces of the first alignment layer and the second alignment layer have orientation.

A liquid crystal layer 250 is positioned between the first alignment layer and the second alignment layer. The liquid crystal molecules of the liquid crystal layer 250 have an initial arrangement state according to the alignment directions of the first and second alignment layers.

A first polarizing plate 260, which is a lower polarizing plate, is attached to the lower surface of the liquid crystal panel 210 through the first adhesive layer 262. That is, one surface of the first polarizing plate 260 is adhered to the first substrate (220 of FIG. 7) of the liquid crystal panel 210 through the first adhesive layer 262.

The first polarizing plate 260 includes a first polarizing layer 260a and first and second protective films 260b and 260c. The first polarization layer 260a is located between the first and second protective films 260b and 260c, and the first protective film 260b, the first polarization layer 260a, and It is positioned in the order of the second protective film 260c.

The first polarization layer 260a may be made of polyvinyl alcohol (PVA), and each of the first and second protective films 260b and 260c is tri-acetyl cellulose (TAC) or cyclic olefin It may be made of a cyclic olefin polymer (COP). Here, the first and second protective films 260b and 260c are also referred to as support films.

A backlight unit (not shown) is positioned under the first polarizing plate 260 to supply light to the liquid crystal panel 210.

On the other hand, a second polarizing plate 270, which is an upper polarizing plate, is attached to the upper surface of the second side of the liquid crystal panel 210 through the second adhesive layer 272. That is, one surface of the second polarizing plate 260 is adhered to the second substrate (240 in FIG. 7) of the liquid crystal panel 210 through the second adhesive layer 272.

The second polarizing plate 270 includes a second polarizing layer 270a and third and fourth protective films 270b and 270c. The second polarization layer 270a is positioned between the third and fourth protective films 270b and 270c, and the third protective film 270b, the second polarization layer 270a, and It is positioned in the order of the fourth protective film 270c.

The second polarization layer 270a may be made of polyvinyl alcohol (PVA), and each of the third and fourth protective films 270b and 270c is tri-acetyl cellulose (TAC) or cyclic olefin. It may be made of a cyclic olefin polymer (COP). Here, the third and fourth protective films 270b and 270c may be referred to as support films.

Each of the first and second adhesive layers 262 and 272 may be formed of an adhesive, that is, a pressure sensitive adhesive (PSA), and the first and second adhesive layers 262 and 272 may be formed of the same material. Alternatively, the first and second adhesive layers 262a and 262b may be formed of different materials.

Adhesives can be divided into a hard type, a middle type, and a soft type according to the size of the modulus, more specifically, the storage modulus, and the elastic modulus is 100,000. When it is more than Pa, it becomes a hard type, when its elastic modulus is 50,000 to 100,000 Pa, it becomes a middle type, and when it is less than 50,000 Pa, it becomes a soft type.

Here, it is preferable that both the first and second adhesive layers 262 and 272 are of a hard type. In this case, the elastic modulus of the first adhesive layer 262 may be the same as the elastic modulus of the second adhesive layer 272.

In the curved liquid crystal display 200 according to the second embodiment of the present invention, since both the first and second adhesive layers 262 and 272 are of a hard type, the first and second polarizing plates 260 and 270 In the case of absorption and expansion, the expansion force of the first polarizing plate 260 and the expansion force of the second polarizing plate 270 are similar, so that the curved state is maintained. Accordingly, the curved liquid crystal display 200 can be prevented from being deformed into a flat state, and light leakage can be prevented.

The amount of warpage of the curved liquid crystal display 200 according to the second embodiment, that is, the distance from the edge to the center of the curved liquid crystal display 200 is determined by using a soft type first adhesive 260. ) Is larger than the curved liquid crystal display attached thereto, and, for example, the amount of warpage of the curved liquid crystal display 200 is about 10 mm or more.

A method of forming a curved surface of a curved liquid crystal display 200 according to a second exemplary embodiment of the present invention will be described with reference to the drawings.

8 is a diagram schematically illustrating an example of a method of forming a curved surface of a curved liquid crystal display according to a second exemplary embodiment of the present invention.

As shown in FIG. 8, a stage 280 having an upper surface convex downward is prepared, and first and second polarizing plates (260, 270 in FIG. 6) are attached to a liquid crystal panel (210 in FIG. 6). The liquid crystal display device 200 is disposed on the upper surface of the stage 280. Here, the liquid crystal display 200 is disposed so that the first polarizing plate (260 of FIG. 6) contacts the upper surface of the stage 280, and has a convex downwardly curved state.

Subsequently, the liquid crystal display 200 is annealed at a constant temperature for a long time to manufacture the curved liquid crystal display 200.

In this case, the annealing should be performed under conditions that do not damage the first and second polarizing plates 260 and 270 in FIG. 6. For example, the annealing temperature may be about 110 degrees or less, preferably, about 80 degrees or less, and more preferably, about 75 degrees. Also, the annealing time may be about 72 hours.

Here, it is preferable that the radius of curvature of the upper surface of the stage 280 is smaller than the radius of curvature of the manufactured curved liquid crystal display 200. In addition, the stage 280 is not limited as long as it is formed of a material that does not deform at an annealing temperature, and as an example, the stage 280 may be made of aluminum or polypropylene (PP).

In this way, by manufacturing the curved liquid crystal display 200 by annealing the liquid crystal display device in a curved state for a long time, stress applied to the display device can be removed, thereby preventing initial light leakage.

9A and 9B are diagrams schematically showing another example of a method for forming a curved surface of a curved liquid crystal display according to a second exemplary embodiment of the present invention.

As shown in FIG. 9A, a first stage 290 having a convex curved top surface is prepared, and a liquid crystal panel 210 is disposed on the top surface of the first stage 290. Here, the liquid crystal panel 210 is disposed such that the second substrate (240 in FIG. 7) contacts the upper surface of the first stage 290, and has a convex curved surface.

Subsequently, by disposing the first polarizing plate 260 on the upper portion of the liquid crystal panel 210 and applying pressure to the outer surface of the first polarizing plate 260 using the first roller 291, the liquid crystal panel 210 in a curved state Attach the first polarizing plate 260 to ). At this time, the first adhesive layer (262 in FIG. 6) of the first polarizing plate 260 contacts the first substrate (220 in FIG. 7) of the liquid crystal panel 210.

Next, as shown in FIG. 9B, a second stage 293 having an upper surface convex downward is prepared, and the liquid crystal panel 210 to which the first polarizing plate (260 in FIG. 9A) is attached is attached to the second stage. It is placed on the top surface of (293). Here, the liquid crystal panel 210 is disposed so that the first polarizing plate (260 in FIG. 9A) contacts the upper surface of the second stage 293, and has a convex downward curved surface.

Then, by disposing the second polarizing plate 270 on the upper portion of the liquid crystal panel 210 and applying pressure to the outer surface of the second polarizing plate 270 using the second roller 294, the liquid crystal panel 210 in a curved state ), a curved liquid crystal display (200 in FIG. 6) is manufactured by attaching the second polarizing plate 270 to each other. At this time, the second adhesive layer (272 in FIG. 6) of the second polarizing plate 270 contacts the second substrate (240 in FIG. 7) of the liquid crystal panel 210.

Here, the order of attaching the first polarizing plate 260 and the second polarizing plate 270 may be different, but it is preferable to attach the second polarizing plate 270 after attaching the first polarizing plate 260.

The method of attaching the polarizing plate in such a curved state may remove stress applied to the display device, thereby preventing initial light leakage. In addition, the method of attaching the polarizing plate in the curved state can reduce the manufacturing cost because the process equipment is simpler than the annealing method, and the manufacturing time can be reduced, thereby increasing productivity.

As described above, in the second embodiment of the present invention, a curved liquid crystal display device (200 in FIG. 6) is manufactured by annealing in a curved state or attaching a polarizing plate in a curved state. By removing the stress applied to it, light leakage can be prevented. In addition, by making both the first and second adhesive layers (262 and 272 in FIG. 6) a hard type and maintaining a curved state, it is possible to prevent the curved liquid crystal display (200 in FIG. 6) from being deformed into a flat state. And can prevent light leakage.

-Third Example-

10 is a schematic cross-sectional view of a curved liquid crystal display according to a third embodiment of the present invention.

As shown in FIG. 10, the curved liquid crystal display 300 according to the third embodiment of the present invention includes a liquid crystal panel 310 which is a display panel, and a first polarizing plate positioned on the first side of the liquid crystal panel 310. And a second polarizing plate 370 positioned on the second side of the liquid crystal panel 310. In addition, the curved liquid crystal display 300 further includes a backlight unit (not shown) positioned under the first polarizing plate 360.

Here, the liquid crystal panel 310 may have the same structure as the liquid crystal panel 210 of FIG. 7 of the curved liquid crystal display according to the second exemplary embodiment illustrated in FIG. 7.

The first polarizing plate 360, which is a lower polarizing plate, is attached to the lower surface of the liquid crystal panel 310 through the first adhesive layer 362.

The first polarizing plate 360 includes a first polarizing layer 360a and first and second protective films 360b and 360c. The first polarization layer 360a is located between the first and second protective films 360b and 360c, and from the lower surface of the liquid crystal panel 310, the first protective film 360b, the first polarization layer 360a, and It is positioned in the order of the second protective film 360c.

The first polarization layer 360a may be made of polyvinyl alcohol (PVA), and each of the first and second protective films 360b and 360c is tri-acetyl cellulose (TAC) or cyclic olefin It may be made of a cyclic olefin polymer (COP).

A backlight unit (not shown) is positioned under the first polarizing plate 360 to supply light to the liquid crystal panel 310.

Meanwhile, a second polarizing plate 370, which is an upper polarizing plate, is attached to the upper surface of the second side of the liquid crystal panel 310 through the second adhesive layer 372. That is, the first surface of the second polarizing plate 370 is adhered to the second substrate (not shown) of the liquid crystal panel 310 through the second adhesive layer 372.

The second polarizing plate 370 includes a second polarizing layer 370a and third and fourth protective films 370b and 370c. The second polarization layer 370a is positioned between the third and fourth protective films 370b and 370c, and the third protective film 370b, the second polarization layer 370a from the top surface of the liquid crystal panel 310, and It is positioned in the order of the fourth protective film 370c.

The second polarization layer 370a may be made of polyvinyl alcohol (PVA), and each of the third and fourth protective films 370b and 370c is tri-acetyl cellulose (TAC) or cyclic olefin. It may be made of a cyclic olefin polymer (COP).

In addition, a third adhesive layer 374 is formed on the second surface of the second polarizing plate 370. Accordingly, the second adhesive layer 372 contacts the third protective film 370b, and the third adhesive layer 374 contacts the fourth protective film 370c.

An auxiliary film 376 is formed on the outer surface of the third adhesive layer 374. Here, the third adhesive layer 374 may be attached to and supplied to the auxiliary film 376 and then attached to the fourth protective film 370c of the second polarizing plate 370. Alternatively, the third adhesive layer 374 may be attached to and supplied to the fourth protective film 370c of the second polarizing plate 370 and then attached to the auxiliary film 376.

The auxiliary film 376 may be an anti-static layer, a hard coating layer, or a low-reflective layer, and a single layer has various functions, or a structure in which layers of various functions are stacked. Can be

Alternatively, the auxiliary film 376 may be a patterned retarder. The patterned retarder includes a left-eye retarder and a right-eye retarder, and the left-eye retarder modulates linearly polarized light into left circularly polarized light and outputs it, and the right-eye retarder modulates and outputs linearly polarized light into right circularly polarized light.

Each of the first, second and third adhesive layers 362, 372, 374 is an adhesive, that is, a pressure sensitive adhesive (PSA), and the first, second and third adhesive layers 362, 372, 374) is preferably a hard type. In this case, the elastic modulus of the first, second, and third adhesive layers 362, 372, and 374 may be the same.

Here, the first, second, and third adhesive layers 362, 372, and 374 may be made of the same material. Alternatively, the first, second, and third adhesive layers 362, 372, and 374 may be formed of different materials.

In the curved liquid crystal display device 300 according to the third embodiment of the present invention, since both the first and second adhesive layers 362 and 372 are of a hard type, the first and second polarizing plates 360 and 370 In the case of absorption and expansion, the expansion force of the first polarizing plate 360 and the expansion force of the second polarizing plate 370 are similar, so that the curved state is maintained. Accordingly, the curved liquid crystal display 300 can be prevented from being deformed into a flat state, and light leakage can be prevented.

In addition, since the third adhesive layer 374 and the auxiliary film 376 are positioned on the second polarizing plate 370, the amount of warpage of the curved liquid crystal display 300 is increased due to adhesion stress, thereby obtaining a large curved effect. . As an example, the amount of warpage of the curved liquid crystal display 200 according to the third embodiment of the present invention is about 16 mm.

A method of forming a curved surface of a curved liquid crystal display device 300 according to a third exemplary embodiment of the present invention will be described with reference to the drawings.

11A to 11C are views schematically showing an example of a method of forming a curved surface of a curved liquid crystal display according to a third exemplary embodiment of the present invention.

As shown in FIG. 11A, a first stage 390 having an upper surface of a convex downwardly curved shape is prepared, and a liquid crystal panel 310 is disposed on the upper surface of the first stage 390. Here, the liquid crystal panel 310 is disposed such that the first substrate (220 in FIG. 7) contacts the upper surface of the first stage 390, and has a convex downwardly curved state.

Then, by disposing the second polarizing plate 370 on the upper portion of the liquid crystal panel 310 and applying pressure to the outer surface of the second polarizing plate 370 using the first roller 391, the liquid crystal panel 310 in a curved state ) Is attached to the second polarizing plate 370. At this time, the second adhesive layer (372 in FIG. 10) of the second polarizing plate 370 contacts the second substrate (240 in FIG. 7) of the liquid crystal panel 310.

Next, as shown in FIG. 11B, a second stage 393 having an upper surface of a convex curved shape is prepared, and the liquid crystal panel 310 to which the second polarizing plate (370 in FIG. 11A) is attached is attached to the second stage ( 393). Here, the liquid crystal panel 310 is disposed so that the second polarizing plate (370 in FIG. 11A) contacts the upper surface of the second stage 393, and has a convex curved surface.

Subsequently, by disposing the first polarizing plate 360 on the upper portion of the liquid crystal panel 310 and applying pressure to the outer surface of the first polarizing plate 360 using the second roller 394, the liquid crystal panel 310 in a curved state ) The first polarizing plate 360 is attached. At this time, the first adhesive layer (362 in FIG. 10) of the first polarizing plate 360 contacts the first substrate (220 in FIG. 7) of the liquid crystal panel 310.

Next, as shown in FIG. 11C, a third stage 396 having an upper surface in the form of a convex downwardly curved surface is prepared, and a liquid crystal panel to which the first polarizing plate (360 in FIG. 11B) and the second polarizing plate 370 are attached. (310 in FIG. 11B) is placed on the upper surface of the third stage 396. Here, the liquid crystal panel (310 in FIG. 11B) is arranged such that the first polarizing plate (360 in FIG. 11B) contacts the upper surface of the third stage 396 and the second polarizing plate 370 is placed on the top, and has a convex downward curved surface. State.

Subsequently, by placing the auxiliary film 376 on the second polarizing plate 370 and applying pressure to the outer surface of the auxiliary film 376 using the third roller 397, the second polarizing plate 370 in a curved state. Attach the auxiliary film 376 to ). At this time, the auxiliary film 376 contacts the second polarizing plate 370 through the third adhesive layer (374 in FIG. 10 ).

Here, the second polarizing plate 370, the first polarizing plate 360, and the auxiliary film 376 are attached in this order. Although the order of attachment may be different, it is preferable to attach the auxiliary film 376 last. For example, the first polarizing plate 360, the second polarizing plate 370, and the auxiliary film 376 may be attached in the order.

The method of attaching the polarizing plate in such a curved state may remove stress applied to the display device, thereby preventing initial light leakage. In addition, the method of attaching the polarizing plate in the curved state can reduce the manufacturing cost because the process equipment is simpler than the annealing method, and the manufacturing time can be reduced, thereby increasing productivity.

Meanwhile, in the curved liquid crystal display according to the third exemplary embodiment of the present invention, a curved surface may be formed through the annealing method of FIG. 8.

As described above, in the third embodiment of the present invention, a curved liquid crystal display device (300 in FIG. 10) is manufactured by annealing in a curved state or by attaching a polarizing plate and an auxiliary film in a curved state, so that the display device in a flat state is artificially bent. In the case of doing so, it is possible to prevent light leakage by removing the stress applied locally. In addition, the first, second, and third adhesive layers (362, 372, 374 in FIG. 10) are all hard-type, and the curved liquid crystal display device (300 in FIG. 10) is transformed into a flat state by maintaining a curved state. It can be prevented from becoming, and light leakage can be prevented.

Although the above has been described with reference to preferred embodiments of the present invention, those skilled in the art will variously modify and change the present invention within the scope not departing from the spirit and scope of the present invention described in the following claims. You will understand that you can do it.

200: curved liquid crystal display 210: liquid crystal panel
260: first polarizing plate 260a: first polarizing layer
260b: first protective film 260c: second protective film
262: first adhesive layer 270: second polarizing plate
270a: second polarization layer 270b: third protective film
270c: fourth protective film 272: second adhesive layer

Claims (9)

A liquid crystal panel;
A first polarizing plate attached to a lower surface of the liquid crystal panel;
A first adhesive layer between the liquid crystal panel and the first polarizing plate;
A second polarizing plate attached to the upper surface of the liquid crystal panel;
A second adhesive layer between the liquid crystal panel and the second polarizing plate
Including,
The first adhesive layer and the second adhesive layer are of a hard type having an elastic modulus of 100,000 Pa or more, and have a bending amount of 10 mm or more.
The method of claim 1,
An auxiliary film attached to an upper portion of the second polarizing plate;
Third adhesive layer between the second polarizing plate and the auxiliary film
Including more,
The third adhesive layer is a curved liquid crystal display device, characterized in that the hard type having an elastic modulus of 100,000 Pa or more.
The method of claim 2,
The auxiliary film is a curved liquid crystal display device, characterized in that the antistatic layer, a hard coating layer, a low reflection layer, or a patterned retarder.
Preparing a liquid crystal panel;
Attaching a first polarizing plate to a lower surface of the liquid crystal panel using a first adhesive layer;
Attaching a second polarizing plate to an upper surface of the liquid crystal panel using a second adhesive layer;
Forming a curved surface on the liquid crystal panel
Including,
The first adhesive layer and the second adhesive layer are of a hard type having an elastic modulus of 100,000 Pa or more, and have a bending amount of 10 mm or more.
The method of claim 4,
The forming of the curved surface is performed after attaching the first polarizing plate and attaching the second polarizing plate, and comprising annealing the liquid crystal panel to which the first and second polarizing plates are attached. A method of manufacturing a curved liquid crystal display device, characterized in that.
The method of claim 4,
The forming of the curved surface is performed before the attaching of the first polarizing plate and the attaching of the second polarizing plate, and comprising disposing the liquid crystal panel on a stage having a curved upper surface. A method of manufacturing a curved liquid crystal display device, characterized in that.
The method of claim 6,
Attaching the first polarizing plate includes attaching the first polarizing plate to the liquid crystal panel disposed on a stage having a convex curved upper surface,
The step of attaching the second polarizing plate comprises attaching the second polarizing plate to the liquid crystal panel disposed on a stage having an upper surface of a curved downwardly convex shape. .
The method of claim 4,
A method of manufacturing a curved liquid crystal display device, further comprising attaching an auxiliary film to an upper portion of the second polarizing plate using a third adhesive layer, wherein the third adhesive layer is of a hard type having an elastic modulus of 100,000 Pa or more. .
The method of claim 1,
The curved liquid crystal display device in which the elastic modulus of the first adhesive layer is the same as that of the second adhesive layer.

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