KR20170121968A - Light guide member for display, backlight unit and liquid crystal display apparatus comprising the same - Google Patents

Abstract

The present invention relates to a flexible light guide member for a display, and a backlight unit and a liquid crystal display including the same. The light guide member according to the present invention comprises: a flexible body; a plurality of first particles provided on a first surface of the body at a first height; and a plurality of second particles provided on the first surface of the body at a second height lower than the first height. Therefore, defective front surface image quality due to a wet-out phenomenon can be prevented.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a light guiding member for a display, and a backlight unit and a liquid crystal display including the light guiding member. 2. Description of the Related Art LIGHT GUIDE MEMBER FOR DISPLAY, BACKLIGHT UNIT AND LIQUID CRYSTAL DISPLAY APPARATUS COMPRISING THE SAME

The present invention relates to a light guide member for a display, a backlight unit including the light guide member, and a liquid crystal display.

A typical liquid crystal display device displays an image using a thin film transistor (Thin Film Transistor) as a switching element. Such a liquid crystal display device can be used as an electronic notebook, an electronic book, a portable multimedia player (PMP), a navigation device, an UMPC (Ultra Mobile PC), a mobile phone, a tablet PC, a smart watch, Such as a television, a notebook, a monitor, a camera, a camcorder, or a home appliance having a display, as well as a mobile electronic device such as a mobile phone, a wearable device, and a mobile communication terminal. Since such a liquid crystal display device is not a self-emission type, an image is displayed using light emitted from a backlight unit disposed under the liquid crystal display panel.

A conventional backlight unit may include a light guide member, a light source that emits light to the light guide member, a reflective sheet disposed below the light guide member, and an optical sheet disposed on the light guide member.

A typical light guide member has a flat plate shape, and is generally made of PMMA (polymethylmethacrylate). Such a general light guide member is suitable for being manufactured in the form of a flat plate, but it is limited in that it is formed in a non-flat plate shape such as a curved shape instead of a flat plate shape. Accordingly, in recent years, research and development on a light guide member using a flexible material, for example, a silicon material, is under way.

However, the silicon material has a tacky characteristic, that is, a cross linking density between the molecules of the PMMA is weak, so that the silicone material becomes sticky when the hardness is low and the soft characteristic is realized. When such a silicon light guide member is applied to a backlight unit, a wet-out phenomenon occurs in which the optical sheet adheres to the light guide member due to the sticky property of the silicone material, The applied backlight unit has a front screen failure due to the wetout phenomenon.

In addition, a general light guide member may include an optical pattern printed on the underside. In this case, the optical pattern may be formed in the form of ink and formed in the light guide member. In this case, there is a problem that adhesion between the silicon material and the optical pattern can not be ensured due to the difference in physical properties between the ink of the optical pattern and the silicon material. Accordingly, when the ink of the optical pattern is molded into the optical guide member made of silicon, there is a problem that the optical pattern is not formed, thereby causing a defective front screen.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a light guiding member for a display and a backlight unit and a liquid crystal display including the same, which can solve the above-described problems.

The light guiding member according to the present invention includes a body made of a flexible material, a plurality of first particles provided on a first surface of the body at a first height, and a plurality of first particles arranged at a second height lower than the first height, 2 < / RTI >

According to the present invention, the sticking wet-out phenomenon between the optical sheet and the light guide member is prevented, so that the defective front image quality due to the wet-out phenomenon can be prevented.

According to the present invention, it is possible to prevent the unflattened pattern of the optical pattern provided on the bottom surface of the light guide member and the defective pattern shape.

In addition to the effects of the present invention mentioned above, other features and advantages of the present invention will be described below, or may be apparent to those skilled in the art from the description and the description.

1 is a cross-sectional view illustrating a light guide member for a display according to an embodiment of the present invention.
2 is a rear view illustrating a light guide member for a display according to an embodiment of the present invention.
Figs. 3 to 6 are diagrams for explaining the shape of the optical pattern having the dot shape according to the composition ratio of the light diffusion ink and the curing conditions. Fig.
7 is a cross-sectional view illustrating another example of the first pattern portion in the light guide member according to an exemplary embodiment of the present invention.
8A and 8B are views illustrating a body of a light guide member according to an exemplary embodiment of the present invention.
9 is a cross-sectional view illustrating a backlight unit according to an exemplary embodiment of the present invention.
10 is a view for explaining the diffusion sheet shown in Fig.
11A and 11B are views for explaining light diffusion particles provided in the diffusion sheet.
12 is an exploded perspective view illustrating a liquid crystal display device according to an exemplary embodiment of the present invention.
13 is an exploded perspective view illustrating a liquid crystal display device according to an exemplary embodiment of the present invention.

The meaning of the terms described herein should be understood as follows.

The word " first, "" second," and the like, used to distinguish one element from another, are to be understood to include plural representations unless the context clearly dictates otherwise. The scope of the right should not be limited by these terms. It should be understood that the terms "comprises" or "having" does not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof. It should be understood that the term "at least one" includes all possible combinations from one or more related items. For example, the meaning of "at least one of the first item, the second item and the third item" means not only the first item, the second item or the third item, but also the second item and the second item among the first item, Means any combination of items that can be presented from more than one. The term "on" means not only when a configuration is formed directly on top of another configuration, but also when a third configuration is interposed between these configurations.

Hereinafter, preferred embodiments of a light guiding member for a display, a backlight unit including the display, and a liquid crystal display according to the present invention will be described in detail with reference to the accompanying drawings. In the drawings, like reference numerals are used to denote like elements throughout the drawings, even if they are shown on different drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

FIG. 1 is a cross-sectional view illustrating a light guide member for a display according to an exemplary embodiment of the present invention, and FIG. 2 is a rear view illustrating a light guide member for a display according to an exemplary embodiment of the present invention.

1 and 2, a display light guide member 100 (hereinafter, referred to as a "light guide member") according to an embodiment of the present invention is formed of a flexible material and has a flat plate shape and / Plane shape such as a curved surface as well as a planar shape so that it can be applied to a backlight unit having a non-flat plate shape of a flat plate. The light guiding member 100 according to an exemplary embodiment includes a body 110 and a first pattern unit 130.

The body 110 is made of a flexible material having a flat face shape and capable of being bent in a non-planar shape. For example, the body 110 may comprise a silicon material. The body 110 according to the present invention comprises a primary curing step in which a typical silicone liquid resin is first cured in an oven with a temperature atmosphere of 110 degrees for 15 minutes and a primary curing step in an oven with a temperature atmosphere of 180 degrees against the primary cured silicone And a secondary curing process in which the secondary curing is performed for 2 hours. Here, the silicon body 110 has a sticky property due to a weak cross linking density between silicon molecules. The present inventors fabricated a first silicon body using only the first curing process and fabricated a second silicon body using the first curing process and the second curing process, As a result of comparing the sticky characteristics between the silicon bodies, it was confirmed that the sticky characteristics of the second silicon body relative to the first silicon body were relatively weak.

The body 110 may include a light incident portion 111 through which light is incident from a light source and the light incident portion 111 may be provided on at least one side of the body 110.

The first pattern unit 130 is provided on the first surface 113 of the body 110. The first surface 113 of the body 110 is formed such that the light incident through the upper surface of the body 110 or the light entering portion 111 with respect to the thickness direction Z of the body 110, Emitting surface of the body 110 to be emitted toward the light-emitting side.

The first pattern unit 130 is provided on the first surface 113 of the body 110 so that an optical sheet (not shown) disposed on the light guide member 110 is attached to the first surface 113 of the body 110, Thereby preventing a phenomenon of sticking to the surface. The first pattern unit 130 includes a plurality of first particles 131 and a plurality of second particles 133 provided on the first surface 113 of the body 110.

Each of the plurality of first particles 131 is provided on the first surface 113 of the body 110 so as to have a first height H1. That is, each of the plurality of first particles 131 is formed to have a first height H1 and a first size to be vertically attached to the first surface 113 of the body 110, Are spaced apart from the first surface 113 of the body 110 by a first height H1. Here, each of the plurality of first particles 131 according to an example may have a size of about 30 탆. Each of the plurality of first particles 131 prevents the optical sheet from sticking to the first surface 113 of the body 110 by supporting the optical sheet.

Each of the plurality of first particles 131 according to an exemplary embodiment may have a hexahedral shape or a pyramidal shape. Here, the upper surface of each of the plurality of first particles 131 facing the optical sheet may have a convex curved surface shape. Each of the plurality of first particles 131 may be provided on the first surface 113 of the body 110 by a dotting method.

Each of the plurality of first particles 131 according to work may be made of a plastic material, for example, a PMMA (polymethylmethacrylate) material. Here, each of the plurality of first particles 131 may be made of the same silicon material as the body 110, but in this case, the optical sheet may adhere to the plurality of first particles 131 made of silicon having sticky characteristics have. Accordingly, each of the plurality of first particles 131 according to the present invention is preferably made of a plastic material having a relatively small or no sticky property with respect to silicon.

Each of the plurality of second particles 133 is provided on the first surface 113 of the body 110 to have a second height H2 lower than the first height H1. That is, each of the plurality of second particles 133 is formed to have a second height H2 and a second size smaller than the first size, and is provided on the first surface 113 of the body 110, 2 particles 133 are disposed closer to the first surface 113 of the body 110 relative to the upper surface of each of the plurality of first particles 131. [ At this time, each of the plurality of second particles 133 may be provided around each of the plurality of first particles 131. Here, each of the plurality of second particles 133 according to an example may have a size of about 5 占 퐉. Each of the plurality of second particles 133 further prevents a portion of the optical sheet between the plurality of first particles 131 from partially sticking to the first surface 113 of the body 110.

Each of the plurality of second particles 133 may have a ball shape or a hexahedral shape, and may include the same material as the first particles 131, or at least one of a plastic material and a silicon material . Here, each of the plurality of second particles 133 may be made of a silicon material because it also diffuses or diffuses the light emitted from the first surface 113 of the body 110. Each of the plurality of second particles 133 may be provided on the first surface 113 of the body 110 by a dotting method or a spray method.

In addition, the first pattern unit 130 may further include a coating layer (not shown) having the plurality of second particles 133. The coating layer may include a plurality of second particles 133 and may be coated on the first surface 113 of the body 110 excluding the plurality of first particles 131. In this case, the coating layer has a lower thickness than the first height H1 of the first particles 131, so that the upper surface of the coating layer is relatively closer to the first surface 131 of the body 110 than the upper surface of each of the plurality of first particles 131 113). The coating layer may be coated on the first side 113 of the body 110 after the plurality of first particles 131 are provided on the first side 113 of the body 110. The coating layer according to another example may be coated on the entire first surface 113 of the body 110 before the plurality of first particles 131. In this case, A part of which is inserted into the coating layer. As described above, when the first pattern unit 130 includes a coating layer, the present invention can more easily form a plurality of second particles 133 on the first surface 113 of the body 110.

The light guide member 100 according to an exemplary embodiment of the present invention further includes a second pattern portion 150 provided on a second surface 115 opposite to the first surface 113 of the body 110. [

The second pattern unit 150 reflects and diffuses the light incident into the body 110 through the light input unit 111 of the body 110 and outputs the light to the first face 113 side of the body 110. The second pattern unit 150 according to an exemplary embodiment includes a plurality of engraved patterns 151 and a plurality of optical patterns 153.

Each of the plurality of engraved patterns 151 is recessed from the second surface 115 of the body 110. Each of the plurality of engraved patterns 151 according to an exemplary embodiment is preferably provided in an elliptical shape having a long axis parallel to the longitudinal direction X of the long side of the body 110, but it is not limited thereto and may be provided in a circular shape. Each of the plurality of engraved patterns 151 includes at least one triangular groove recessed from the second surface 115 of the body 110 so as to have a triangular cross-sectional shape. Each of the triangular grooves may have a regular triangular cross-section or an isosceles triangular cross-sectional shape, which is elongated so as to be parallel to the longitudinal direction Y of the short side of the body 110, that is, the light entering portion 111 of the body 110. Each of the plurality of engraved patterns 151 reflects light incident through the inside of the body 110 toward the first side 113 of the body 110.

Each of the plurality of optical patterns 153 is provided on a second surface 115 of the body 110 corresponding to a space between the plurality of engraved patterns 151. The optical pattern 153 and the engraved pattern 151 are alternately provided on the second surface 115 of the body 110 along the longitudinal direction X of the long side of the body 110, The optical pattern 153 and the engraved pattern 151 are alternately provided along the short side direction Y. [ That is, the optical pattern 153 and the engraved pattern 151 are formed on the body 110 so as to have a zigzag shape along the longitudinal direction X of the long side of the body 110 and the longitudinal direction Y of the short side of the body 110, respectively. On the second surface 115 of the substrate.

Each of the plurality of optical patterns 153 is formed to have a predetermined height on the second surface 115 of the body 110 to diffuse light incident through the inside of the body 110 A reflective sheet (not shown) disposed under the light guide member 100 is prevented from sticking to the second surface 115 of the body 110. Each of the plurality of optical patterns 153 according to an exemplary embodiment is preferably provided in an elliptical shape having a long axis parallel to the longitudinal direction X of the long side of the body 110, but it is not limited thereto and may be provided in a circular shape.

Each of the plurality of optical patterns 153 may be formed by a printing process using a light diffusion ink. At this time, the light diffusion ink includes a resin, a diffusing agent, and a curing accelerator, and the adhesion force between the light diffusion ink and the body 110 varies depending on the composition ratio. Accordingly, the optical diffusion ink according to the present invention includes a resin made of silica, a diffusing agent composed of silica particles and PMMA (polymethylmethacrylate) particles, and a curing accelerator for optimum adhesion and shape realization, Of the total weight of the light-diffusing ink, the diffusing agent has 13% to 18% by weight of the total weight of the light-diffusing ink, and the curing accelerator has a total weight of the light- About 0.4% by weight. Here, the resin may further include a PMMA material. In this case, the composition of the resin may include 95% by weight of silica material and 5% by weight of PMMA material. The composition of the diffusing agent may include 40% by weight of silica material and 60% by weight of PMMA material. For example, considering both the adhesive force between the silicon body 110 and the optical pattern 153 and the shape implementation, the optimum light diffusion ink composition is 84.6 wt% resin, 15 wt% % ≪ / RTI > cure accelerator.

In addition, not only the composition of the light diffusion ink but also the curing conditions of the ink act as key parameters for realizing the adhesion force and shape between the silicon body 110 and the optical pattern 153. The curing process of the light diffusion ink having the above composition ratio is preferably carried out in an oven having a temperature atmosphere of approximately 120 degrees for 30 minutes. Here, when the composition ratio of the resin in the light diffusion ink is less than 82% by weight or exceeds 87% by weight, as the temperature of the curing process is increased to 120 degrees or more, Problems can arise.

For reference, in order to find an optimal pattern attaching force and an ink composition ratio capable of achieving a shape, the inventors conducted an experiment of eight combinations as shown in Figs. 3 to 6. Figs. 3 to 6 are diagrams for explaining the shape of the optical pattern having the dot shape according to the composition ratio of the light diffusion ink and the curing conditions. Fig.

First, the present inventors have found that the composition ratio of the resin in the composition of the light diffusion ink is set differently within 82 wt% to 87 wt%, and the composition ratio of the diffusing agent is set differently within 13 wt% to 18 wt% 1 to 4, and the first to fourth light diffusing inks were respectively formed on the light guiding member made of silicon and the first to fourth samples (# 1, # 2, # 3, # 4 ) Was printed and cured in an oven with a temperature atmosphere of approximately 120 degrees for 30 minutes to measure the adhesion and shape of each of the cured first to fourth samples (# 1, # 2, # 3, and # 4). As a result, as shown in FIG. 3, each of the first to fourth samples (# 1, # 2, # 3, and # 4) showed the best adhesive force level and shape level.

The present inventors also modified the curing conditions and cured for 30 minutes in an oven having a temperature atmosphere of approximately 150 degrees for the printed first to fourth samples (# 1, # 2, # 3, # 4) The adhesive force and shape of each of the first to fourth samples (# 1, # 2, # 3, and # 4) were measured. 4, each of the first to fourth samples (# 1, # 2, # 3, and # 4) had an excellent adhesive force level, but it was confirmed that the pattern forming defects were different according to the pattern unformed portions .

The present inventors also prepared a fifth light diffusion ink by setting the composition ratio of the resin to less than 82 wt% in the composition of the light diffusion ink, setting the composition ratio of the resin to more than 87 wt% After printing the fifth and sixth samples (# 5 and # 6) having a dot shape on the silicon-based light guide member, the fifth and sixth light-diffusing inks were each printed with a temperature atmosphere of approximately 120 degrees , And the adhesion and shape of each of the cured fifth and sixth samples (# 5, # 6) were measured. 5, each of the fifth and sixth samples (# 5 and # 6) has a relatively weak adhesive force as compared with the first to fourth samples (# 1, # 2, # 3, and # 4) And it was confirmed that pattern formation defects due to pattern unforming at the central portion of the pattern are exhibited.

Further, the present inventors changed the curing conditions and cured for 30 minutes in an oven having a temperature atmosphere of approximately 150 degrees for the printed fifth and sixth samples (# 5, # 6), and cured fifth and sixth samples The adhesion and shape of each of the samples (# 5 and # 6) were measured. 5, each of the fifth and sixth samples (# 5 and # 6) has a relatively weak adhesive force as compared with the first to fourth samples (# 1, # 2, # 3, and # 4) And it is confirmed that pattern formation defects due to non-pattern forming as a whole are exhibited.

As a result, as can be seen from FIGS. 3 to 6, considering the adhesive force and the shape of the flexible material, that is, the silicone material, the light diffusion ink according to the present invention comprises 82 wt% to 87 wt% , 13% to 18% by weight of a dispersing agent consisting of silica particles and PMMA particles, and less than 0.4% by weight of a curing accelerator, and cured in an oven with a temperature atmosphere of approximately 120 degrees for 30 minutes. Therefore, the present invention can prevent the image quality defect due to unformed optical pattern 153.

7 is a cross-sectional view illustrating another example of the first pattern portion in the light guide member according to an exemplary embodiment of the present invention.

Referring to FIG. 7, the first pattern unit 130 according to another example includes a plurality of lens patterns 135, a plurality of first particles 131, and a plurality of second particles 133.

Each of the plurality of lens patterns 135 is formed to be convex from the first surface 113 of the body 110. That is, each of the plurality of lens patterns 135 protrudes convexly from the first surface 113 of the body 110 and extends long to be parallel to the longitudinal direction X of the long side of the body 110, Are arranged side by side along the short side direction (Y). Each of the plurality of lens patterns 135 according to an example is provided on the first surface 113 of the body 110 so as to have a pitch P1 of 250 mu m to 300 mu m and a height H3 of 20 mu m to 50 mu m Or a lenticular lens having a hemispherical shape or a semi-elliptical shape. Each of the plurality of lens patterns 135 improves the straightness and condensing efficiency of the light incident on the body 110 through the lens shape and allows the first surface 113 of the body 110 and the optical surface Thereby reducing the contact area.

Each of the plurality of first particles 131 and the plurality of second particles 133 is provided on the surface of each of the plurality of lens patterns 135.

Each of the plurality of first particles 131 is provided at a vertex of each of the plurality of lens patterns 135 so as to have a first height H1. That is, each of the plurality of first particles 131 is formed to have a first height H1 and a first size, and is attached to the vertex of each of the plurality of lens patterns 135 vertically. Each of the plurality of first particles 131 may be provided at a vertex of each of the plurality of lens patterns 135 by a dotting method. Each of the plurality of first particles 131 is provided at a vertex of each of the plurality of lens patterns 135 to support the optical sheet to prevent the optical sheet from sticking to the first surface 113 of the body 110 1, and thus a duplicate description thereof will be omitted.

Each of the plurality of second particles 133 may be provided below a vertex of each of the plurality of lens patterns 135 so as to have a second height H2 lower than the first height H1. That is, each of the plurality of second particles 133 is provided on the surface of the lens pattern 135 corresponding to the periphery of each of the plurality of first particles 131. Each of the plurality of second particles 133 may be provided on each of the plurality of lens patterns 135 by a dotting method or a spray method so that the plurality of second particles 133 may be formed relatively to the upper surface of each of the plurality of first particles 131 110). ≪ / RTI > Each of the plurality of second particles 133 may be provided around each of the plurality of first particles 131 so that the optical sheet portion between the plurality of first particles 131 may be provided on the first surface 131 of the body 110 113, except that it is additionally prevented from partially sticking to the second particles 113. Therefore, a duplicate description thereof will be omitted.

In addition, the first pattern unit 130 may further include a coating layer (not shown) having the plurality of second particles 133. The coating layer may be formed to include a plurality of second particles 133 and may be coated on the surface of each of the plurality of lens patterns 135 except for the apexes of the plurality of lens patterns 135. In this case, the coating layer has a lower thickness than the first height H1 of the first particles 131, so that the upper surface of the coating layer is relatively closer to the first surface 131 of the body 110 than the upper surface of each of the plurality of first particles 131 113). The coating layer according to an example may be coated on each of the plurality of lens patterns 135 after the plurality of first particles 131 are provided at apexes of each of the plurality of lens patterns 135. The coating layer according to another example may be coated on each of the plurality of lens patterns 135 before the plurality of first particles 131. In this case, And may be inserted into the coating layer on the apexes of the plurality of lens patterns 135. As described above, when the first pattern unit 130 includes a coating layer, the present invention can more easily form the plurality of second particles 133 on the plurality of lens patterns 135. [

The light guiding member 100 including the first pattern unit 130 according to another exemplary embodiment may include a plurality of lens patterns 135 and a plurality of first particles 131, It is possible to more effectively prevent the phenomenon that the optical sheet sticks to the first surface 113 of the body 110 by increasing the distance between the optical sheet 113 and the optical sheet.

8A and 8B are views illustrating a body of a light guide member according to an exemplary embodiment of the present invention.

First, as shown in FIG. 8A, the body 110 of the light guide member 100 according to an exemplary embodiment may have a disc shape. The light guiding member 100 having the body 110 in the form of a disk can be applied to a circular backlight unit that emits light to the circular liquid crystal display panel.

In addition, the body 110 of the light guide member 100 according to an exemplary embodiment may have a non-rectangular shape as well as a disc shape.

Next, as shown in FIG. 8B, the body 110 of the light guide member 100 according to an exemplary embodiment may have a curved shape.

The body 110 according to an exemplary embodiment may have a curved shape curved in an S shape between a pair of short sides. The body 110 may include one side long side having a curved shape and / or a light incident portion provided on the other side.

The body 110 according to another example includes a first plane portion 110a extending in a planar shape from one short side, a second plane portion 110b extending in a plane form from the other short side toward the first plane portion 110a, And a curved surface portion 110c bent in a curved shape between the first and second flat surfaces 110a and 110b. The body 110 may include a first planar portion 110a, a second planar portion 110b and a curved portion 110c. The curved portion 110c may include a long side and / or a long side.

In addition, the curved surface portion 110c of the body 110 according to another example includes a first curved surface portion curved in a curved surface form from the first flat surface portion 110a, a second curved surface portion curved in a curved shape from the second flat surface portion 110b, And a third planar portion having a planar shape between the first curved portion and the second curved portion.

The light guide member 100 having the body 110 including the curved surface portion 110c may be applied to a curved surface backlight unit that emits light to the curved display panel.

9 is a cross-sectional view illustrating a backlight unit according to an exemplary embodiment of the present invention.

Referring to FIG. 9, a backlight unit according to an exemplary embodiment of the present invention includes a light guide member 100, a light source 200, a reflective sheet 300, and an optical sheet unit 400.

The light guide member 100 irradiates the entire lower surface of the optical sheet unit 400 with light incident from the light source unit 200. Since the light guide member 100 has the same configuration as that of the light guide member for a display shown in FIGS. 1 to 8, the same reference numerals are assigned to the light guide member 100, and a duplicate description thereof will be omitted.

The light source unit 200 irradiates the light entering unit 111 provided in the light guide member 100 with light. The light source 200 according to an exemplary embodiment includes a printed circuit board 210 and a plurality of light emitting diodes 220

The printed circuit board 210 is disposed to face the light-incident portion 111 of the light guide member 100. The printed circuit board 210 may include a light source driving power line and a light source common power line.

Each of the plurality of light emitting diodes 220 is mounted on the printed circuit board 210 so as to be spaced apart from each other and irradiate light to the light entering portion 111 of the light guiding member 100. That is, each of the plurality of light emitting diodes 220 is mounted on the printed circuit board 210 to be electrically connected to the light source driving power supply line and the light source common power supply line, and is emitted by the light source driving power supply supplied from the light source driving power supply line And irradiates the light entering portion 111 of the light guide member 100 with light.

The reflective sheet 300 is disposed under the light guide member 100 to minimize light loss by reflecting the light emitted to the lower surface of the light guide member 100 into the light guide member 100. The reflective sheet 300 is brought into point contact with a plurality of optical patterns 153 provided on the light guide member 100 and thereby the body 110 of the light guide member 100 made of a flexible material, . That is, each of the plurality of optical patterns 153 provided on the light guide member 100 is provided on the second surface 115 of the body 110 to diffuse the light incident from the inside of the body 110, Is prevented from sticking to the second surface 115 of the body 110 made of a sticky silicone material.

The optical sheet unit 400 is disposed on the first surface 113 of the light guide member 100 and functions to improve the brightness characteristic of light emitted from the first surface 113 of the light guide member 100 . The optical sheet portion 400 according to an exemplary embodiment may include a diffusion sheet 410, a prism sheet 420, and a dual brightness enhancement film 430.

The diffusion sheet 410 is disposed on the lowest layer of the optical sheet unit 400 so as to directly face the first surface 113 of the light guide member 100 and has a body 110 made of a sticky silicon material, The first surface 113 of the substrate 110 can be adhered to the first surface 113 of the substrate. The diffusion sheet 410 does not adhere to the first surface 113 of the body 110 by being supported by the first pattern portion 130 provided on the first surface 113 of the light guide member 100. [ That is, the diffusion sheet 410 is supported by the plurality of first particles 131 included in the first pattern unit 130 and separated from the first surface 113 of the body 110, And does not stick to the first surface 113. A part of the diffusion sheet disposed between the plurality of first particles 131 is additionally supported by the plurality of second particles 133 included in the first pattern part 130, And does not stick to the surface 113. In other words, the first pattern part 130 including the plurality of first particles 131 and the plurality of second particles 133 is provided on the first surface 113 of the body 110 at different heights, Out phenomenon that the sheet 410 adheres to the first surface 113 of the body 110 is prevented so that the front screen defect of the backlight unit due to the wet-out phenomenon is prevented. Here, when the first pattern portion 130 includes a plurality of lens patterns 135 and a plurality of first particles 131 and a plurality of second particles 133, the wet-out phenomenon can be more effectively prevented have.

10, the diffusion sheet 410 may be provided on the facing surface 411 facing the first surface 113 of the light guide member 110, as shown in FIG. 10, to prevent the wet- And further includes light-diffusing particles (413).

The light diffusion particles 413 prevent diffusion of light incident from the light guide member 110 while preventing the diffusion sheet 410 from sticking to the light guide member 110. The light-diffusing particles 413 according to an example may have a size of less than 5 mu m, and preferably have a size of 3 mu m, for example.

As shown in Fig. 11A, the present inventors have found that a sample A having light diffusing particles 413 having a size of 5 mu m and a light diffusing particle 413 having a size of 3 mu m, as shown in Fig. 11B, Out phenomenon between the diffusion sheet 410 and the light guide member 110 was experimented and it was found that the sample It was confirmed that the wet-out phenomenon did not occur in the sample B relative to the sample A. Accordingly, the light-diffusing particles 413 according to an example may have a size of less than 5 mu m, more preferably, 3 mu m.

The backlight unit according to an exemplary embodiment of the present invention may include a plurality of first particles 131 provided at different heights and a plurality of second particles 133 on the first surface 113 of the body 110, Out phenomenon that the sheet 410 adheres to the first surface 113 of the body 110 made of a sticky silicon material is prevented, thereby preventing a front screen failure due to a wet-out phenomenon. In addition, the backlight unit according to an exemplary embodiment of the present invention can more effectively prevent the wet-out phenomenon by the light diffusion particles 413 having a size of less than 5 mu m provided on the lower surface 411 of the diffusion sheet 410. [

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

Referring to FIG. 12, a liquid crystal display device according to an exemplary embodiment of the present invention includes a backlight unit 500 and a liquid crystal display panel 600.

The backlight unit 500 includes a light guide member 100, a light source 200, a reflective sheet 300, and an optical sheet unit 400. This backlight unit 500 is a circular backlight unit and has the same configuration as the backlight unit shown in Fig. 10 except that it has a circular shape. That is, each of the light guide member 100, the reflection sheet 300, and the optical sheet unit 400 has a disk shape, and the light source unit 200 has a ring shape And irradiates light to the light-incident portion provided on the circumferential surface of the light guide member 100. [ The backlight unit 500 is housed in a housing (not shown) having a storage space.

The liquid crystal display panel 600 displays an image using light emitted from the backlight unit 500. That is, the liquid crystal display panel 600 may include a first substrate having a thin film transistor array, a second substrate having a color filter array, and a liquid crystal layer provided between the first and second substrates. The liquid crystal display panel 600 may have a circular shape corresponding to the backlight unit 500.

The liquid crystal display device according to an exemplary embodiment of the present invention may further include a guide frame (not shown) supported by the housing and coupled with the liquid crystal display panel 600. The guide frame may include a panel support portion attached to a bottom edge portion of the liquid crystal display panel 600 by a panel attachment member (not shown), and a guide sidewall perpendicularly connected to the panel support portion to surround the side surface of the housing.

The liquid crystal display device according to an exemplary embodiment of the present invention includes a backlight unit that prevents a wetout phenomenon between the diffusion sheet 410 and the light guide member 100, have. The liquid crystal display device according to an exemplary embodiment of the present invention can be applied to a display screen of a circular watch phone or a circular display device.

12, each of the backlight unit 500 and the liquid crystal display panel 600 has a circular shape. However, the present invention is not limited thereto, and the backlight unit 500 and the liquid crystal display panel 600 may have a rectangular shape. Lt; / RTI >

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

Referring to FIG. 13, a liquid crystal display device according to an exemplary embodiment of the present invention includes a backlight unit 700 and a liquid crystal display panel 800.

The backlight unit 700 includes a light guide member 100, a light source 200, a reflective sheet 300, and an optical sheet unit 400. This backlight unit 700 is a curved backlight unit and has the same configuration as the backlight unit shown in Fig. 10 except that it has a curved shape. That is, each of the light guide member 100 and the light source unit 200 is formed in a curved shape, and the reflective sheet 300 is formed in a curved shape below the light guide member 100 so as to correspond to the curved shape of the light guide member 100. [ And the optical sheet unit 400 is also arranged in a curved shape on the light guide member 100 so as to correspond to the curved shape of the light guide member 100. [ The backlight unit 700 is accommodated in a housing (not shown) having a curved storage space corresponding to the curved shape of the light guide member 100.

The liquid crystal display panel 800 displays an image using light emitted from the backlight unit 700. That is, the liquid crystal display panel 800 may include a first substrate having a thin film transistor array, a second substrate having a color filter array, and a liquid crystal layer provided between the first and second substrates. The liquid crystal display panel 800 has a curved shape corresponding to the curved shape of the light guide member 100.

The liquid crystal display device according to an exemplary embodiment of the present invention may further include a guide frame (not shown) supported by the housing and coupled to the liquid crystal display panel 800. The guide frame may include a panel support portion attached to a bottom edge portion of the liquid crystal display panel 800 by a panel attachment member (not shown), and a guide sidewall perpendicularly connected to the panel support portion to surround the side surface of the housing. Here, the panel support portion of the guide frame has a curved surface shape corresponding to the curved surface shape of the liquid crystal display panel 800.

The liquid crystal display device according to an exemplary embodiment of the present invention includes a backlight unit that prevents a wetout phenomenon between the diffusion sheet 410 and the light guide member 100, thereby preventing a poor image quality due to a wetout phenomenon have. The liquid crystal display device according to an exemplary embodiment of the present invention can be applied to a display device of an automobile operation panel including a curved shape.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents. Will be clear to those who have knowledge of. Therefore, the scope of the present invention is defined by the appended claims, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be interpreted as being included in the scope of the present invention.

100: light guide member 110: body
130: first pattern part 131: first particle
133: second particle 135: lens pattern
150: second pattern unit 151: engraved pattern
153: optical pattern 200:
300: reflective sheet 400: optical sheet part
410: diffusion sheet 413: light diffusion particle
500, 700: backlight unit 600, 800: liquid crystal display panel

Claims (15)

A body made of a flexible material; And
And a first pattern portion provided on a first surface of the body,
Wherein the first pattern portion comprises:
A plurality of first particles provided on a first surface of the body at a first height; And
And a plurality of second particles provided on a first surface of the body at a second height lower than the first height. The method according to claim 1,
And a second pattern portion provided on a second surface opposite to the first surface of the body,
Wherein the second pattern portion comprises:
A plurality of engraved patterns recessed from a second surface of the body; And
And a plurality of optical patterns provided on the second surface of the body and provided between the plurality of engraved patterns. 3. The method of claim 2,
Wherein each of the plurality of optical patterns is provided by curing a light diffusion ink,
Wherein the light diffusion ink comprises
A resin made of silica;
A dispersing agent composed of silica particles and PMMA (Polymethylmethacrylate) particles; And
A light guide member for a display comprising a curing accelerator. The method of claim 3,
Wherein the resin has from 82 wt% to 87 wt% of the total weight of the light diffusion ink,
Wherein the diffusing agent has 13 wt% to 18 wt% of the total weight of the light diffusion ink. 3. The method of claim 2,
Wherein the first pattern portion further comprises a coating layer having the plurality of second particles,
Wherein the coating layer is coated on the first surface of the body except for the plurality of first particles. 3. The method of claim 2,
Wherein the first pattern portion further includes a plurality of lens patterns convexly formed from a first surface of the body,
Wherein each of the plurality of first particles is provided at a vertex of each of the plurality of lens patterns,
And each of the plurality of second particles is provided on a surface below a vertex of each of the plurality of lens patterns. The method according to claim 6,
Wherein the first pattern portion further comprises a coating layer having the plurality of second particles,
Wherein the coating layer is coated on each of the plurality of lens patterns other than the apexes of each of the plurality of lens patterns. The method according to claim 1,
Wherein the plurality of first particles comprise a plastic material,
Wherein the plurality of second particles comprise at least one of a plastic material and a silicon material. 9. The method according to any one of claims 1 to 8,
Wherein the body comprises a silicon material. A light guide member for a display according to any one of claims 1 to 8;
A light source unit for emitting light to the light guide member;
A reflective sheet disposed below the light guide member; And
And an optical sheet portion disposed on the light guide member. 11. The method of claim 10,
Wherein the optical sheet portion includes a diffusion sheet supported by a first pattern portion of the light guide member,
Wherein the diffusion sheet comprises light diffusing particles having a size of less than 5 mu m while being provided on an opposed surface facing the light guide member. 11. The method of claim 10,
Wherein the body of the light guide member comprises a silicone material. A liquid crystal display panel; And
The liquid crystal display device according to claim 1, wherein the backlight unit irradiates the liquid crystal display panel with light. 14. The method of claim 13,
Wherein the optical sheet portion of the backlight unit includes a diffusion sheet supported by the first pattern portion of the light guide member,
Wherein the diffusion sheet is provided on an opposite surface facing the light guide member and includes light diffusion particles having a size of less than 5 mu m. 15. The method of claim 14,
Wherein the body of the light guide member comprises a silicon material.

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