KR20220076825A - Liquid crysatl display device - Google Patents

Abstract

A liquid crystal display device according to an embodiment of the present invention includes a liquid crystal display panel on which an image is displayed, a plurality of mini-LEDs disposed under the liquid crystal display panel to provide light, and a resin layer disposed between the plurality of mini-LEDs. and a pattern sheet disposed between the liquid crystal display panel and the plurality of mini-LEDs and having a reflective pattern on at least one surface, wherein the reflective pattern includes a plurality of central reflective patterns positioned corresponding to the mini-LEDs and the It is composed of a plurality of sub-reflection patterns positioned outside the central reflection pattern, and the performance of the mini LED can be secured without increasing the thickness of the backlight unit.

Description

Liquid crystal display device {LIQUID CRYSATL DISPLAY DEVICE}

The present invention relates to a liquid crystal display device, and more particularly, to a liquid crystal display device having a mini-LED (Light Emitting Diode; LED).

As the modern society gradually develops into an information society, as the demand for home appliances, various portable electronic devices, etc. increases, the demand for a lightweight and thin flat panel display device is also increasing.

A double liquid crystal display is a flat panel display that displays an image by controlling the amount of light passing through the liquid crystal, and is widely used due to advantages such as thinness and low power consumption.

Unlike a cathode ray tube (CRT), a liquid crystal display is not a display device that emits light by itself, so a backlight unit including a separate light source that provides light to visually express an image is located on the rear surface of the liquid crystal display panel. this is provided

The backlight unit is provided with a lamp or a Light Emitting Diode (LED) as a light source. Recently, LEDs that are advantageous for low power consumption and slimming have been used.

As the light energy conversion efficiency of LED increases with the progress of research on LED, LED is rapidly replacing the existing light emitting device. LEDs currently being developed have advantages such as miniaturization, light weight, and low power consumption. Accordingly, LEDs are being actively used as light sources for various image display devices.

The size of the LED chip is gradually getting smaller. Examples of miniature LED chips are mini LEDs and micro LEDs. In the mini LED and micro LED, each LED chip individually becomes a pixel or a light source, so restrictions on the size and shape of a display device are eliminated, and sharper image quality can be realized than when a conventional light source is used.

Although the number of mini LED chips is being reduced to secure cost competitiveness, in this case, the pitch between mini LED chips increases and the thickness of the product increases to secure a light diffusion distance.

Accordingly, an object of the present invention is to provide a liquid crystal display device capable of reducing the thickness of a backlight unit by reducing the number of mini-LED chips and securing performance of the mini-LEDs.

The problems of the present invention are not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

In order to solve the above problems, a liquid crystal display device according to an embodiment of the present invention includes a liquid crystal display panel on which an image is displayed, a plurality of mini LEDs disposed under the liquid crystal display panel to provide light, and the plurality of a resin layer disposed between the mini-LEDs of It may be composed of a plurality of central reflective patterns positioned and a plurality of sub-reflective patterns positioned outside the central reflective pattern.

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

The present invention can secure the performance of the mini LED without increasing the thickness of the backlight unit, and provides effects of improving lattice mura, improving light efficiency, and securing reliability.

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

1 is a cross-sectional view of a liquid crystal display according to a first exemplary embodiment of the present invention.
2A and 2B are cross-sectional views showing another form of an optical clear resin (OCR) layer of the present invention.
3 is a view for explaining a reflection pattern of the present invention.
4A to 4D are perspective views illustrating various shapes of a reflective pattern according to the present invention.
5A to 5E are views illustrating various arrangements of the reflective pattern according to the present invention.
6A and 6B are cross-sectional views illustrating a light diffusion distance according to a pitch between mini LED chips.
7 is a view showing a liquid crystal display to which various arrays of reflective patterns are applied.
8A to 8E are images showing image quality according to various arrangements of the reflection patterns of FIG. 7 .
9A to 9D are images showing a lattice mura according to application of a reflective pattern.
10A to 10G are images showing images according to the size and thickness of the reflection pattern.
11 is a cross-sectional view of a liquid crystal display according to a second exemplary embodiment of the present invention.
12 is a cross-sectional view of a liquid crystal display according to a third exemplary embodiment of the present invention.
13 is a cross-sectional view of a liquid crystal display according to a fourth exemplary embodiment of the present invention.
14 is a cross-sectional view of a liquid crystal display according to a fifth exemplary embodiment of the present invention.

Advantages and features of the present invention and methods of achieving them will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be embodied in various different forms, and only these embodiments allow the disclosure of the present invention to be complete, and common knowledge in the art to which the present invention pertains It is provided to fully inform those who have the scope of the invention, and the present invention is only defined by the scope of the claims.

The shapes, sizes, proportions, angles, numbers, etc. disclosed in the drawings for explaining the embodiments of the present invention are illustrative and the present invention is not limited to the illustrated matters. In addition, in describing the present invention, if it is determined that a detailed description of a related known technology may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted. In addition, when 'including', 'having', 'consisting', etc. mentioned in this specification are used, other parts may be added unless 'only' is used. When a component is expressed in the singular, the case in which the plural is included is included unless otherwise explicitly stated.

In interpreting the components, it is construed as including an error range even if there is no separate explicit description.

In the case of a description of the positional relationship, for example, when the positional relationship of two parts is described as 'on', 'on', 'on', 'beside', etc., 'right' Alternatively, one or more other parts may be positioned between two parts unless 'directly' is used.

When a device or layer is referred to as "on" another device or layer, it includes cases in which another layer or other device is interposed directly on or in the middle of another device.

Although first, second, etc. are used to describe various elements, these elements are not limited by these terms. These terms are only used to distinguish one component from another. Accordingly, the first component mentioned below may be the second component within the spirit of the present invention.

Like reference numerals refer to like elements throughout.

The size and thickness of each component shown in the drawings are illustrated for convenience of description, and the present invention is not necessarily limited to the size and thickness of the illustrated component.

Each feature of the various embodiments of the present invention may be partially or wholly combined or combined with each other, and as those skilled in the art will fully understand, technically various interlocking and driving are possible, and each embodiment may be implemented independently of each other, It may be possible to implement together in a related relationship.

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

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

2A and 2B are cross-sectional views showing another form of an optical clear resin (OCR) layer of the present invention.

Referring to FIG. 1 , a liquid crystal display 100 according to a first embodiment of the present invention includes a liquid crystal display panel 110 on which an image is displayed and a backlight unit disposed below the liquid crystal display panel 110 to provide light. may include

Also, in the liquid crystal display 100 according to the first embodiment of the present invention, the panel guide 140 supporting the lower edge of the liquid crystal display panel 110 and the lower cover 145 accommodate the backlight unit and surround the side edge. may further include.

For reference, the panel guide 140 may be referred to by other names such as a mold frame, and the lower cover 145 may be referred to by other names such as a bottom cover, a lower case, and a cover bottom. Not limited by name.

The lower cover 145 may serve to protect the printed circuit board 123 of the light source unit 120 and fix the liquid crystal display panel 110 .

The liquid crystal display panel 110 faces each other and is interposed between the color filter substrate 101 and the thin film transistor substrate 111 and the color filter substrate 101 and the thin film transistor substrate 111 bonded to each other to maintain a uniform cell gap. It may include a liquid crystal layer (not shown).

Although not shown, in the thin film transistor substrate 111, a plurality of gate lines and data lines intersect to define one pixel, and a thin film transistor (TFT) is provided in each intersecting area to each It may be connected in a one-to-one correspondence with the pixel electrode mounted on the pixel.

The color filter substrate 101 may include R, G, and B color filters corresponding to each pixel, a black matrix that borders each of them and covers gate lines, data lines, thin film transistors, etc., and a common electrode covering them all. can

However, the present invention is not limited to the TN (Twisted Nematic) mode in which the common electrode is formed on the color filter substrate 101, and the present invention is not limited to the IPS (Twisted Nematic) mode in which both the pixel electrode and the common electrode are disposed on the thin film transistor substrate 111. It can be applied to In Plane Switching) mode and FFS (Fringe Field Switching) mode.

A driving printed circuit board (PCB) for supplying driving signals to a gate line and a data line may be provided at an edge (edge) of the liquid crystal display panel 110 . The driving PCB may be electrically connected to the liquid crystal display panel 110 by a Chip on Film (COF), and the COF may be changed to a Tape Carrier Package (TCP).

A light blocking tape 146 may be provided between the liquid crystal display panel 110 at the edge of the liquid crystal display panel 110 , the panel guide 140 , and the lower cover 145 , but the present invention is not limited thereto.

The backlight unit includes the light source unit 120 disposed inside the lower cover 145 , the pattern sheet 130 disposed on the light source unit 120 , and the optical sheet 125 disposed on the pattern sheet 130 . may include

The light source unit 120 may include a printed circuit board 123 and a plurality of LEDs 121 disposed at regular intervals on the printed circuit board 123 . The printed circuit board 123 may be formed of a metal PCB having excellent thermal conductivity.

The printed circuit board 123 may serve to prevent cracks in the plurality of LEDs 121 .

The LED 121 is a large LED in which the size of the LED chip is 1,000 μm or more, a middle LED in which the size of the LED chip is 300-500 μm, and the size of the LED chip according to the size of the LED chip. It can be classified into a small LED having a size of 200-300 μm, a mini LED having a size of an LED chip of 100-200 μm), and a micro LED having a size of an LED chip of 100 μm or less. Here, the LED 121 may include a material such as InGaN or GaN.

As the size of the LED chip decreases, the number of LEDs 121 can be easily adjusted, so that the luminance characteristics and color uniformity of the liquid crystal display 100 can be improved and slim. In addition, as the size of the LED chip becomes smaller, power consumption can be reduced, thereby reducing battery consumption of the portable device and extending the lifespan of the battery.

In addition, when the mini LED 121 or the micro LED is used compared to the conventional LED, the size of the LED 121 is reduced, so that local dimming is possible. Local dimming can improve picture quality and save power. Here, the local dimming is a technology that controls the brightness of the LED 121 used as a backlight based on the configuration or characteristics of the screen, and is a technology that can dramatically improve a contrast ratio and reduce power consumption. As an example of local dimming, a dark color is expressed by adjusting the brightness of the mini LED 121 or micro LED corresponding to a dark screen to be relatively dark, and the brightness of the mini LED 121 or micro LED corresponding to a bright screen is relatively dark. It can be brightened to express vivid colors.

An adhesive layer may be further disposed between the printed circuit board 123 and the lower cover 145 , but is not limited thereto.

An optical clear resin (OCR) layer 122 that is a transparent resin layer may be disposed between the mini LEDs 121 of the present invention. At this time, the OCR layer 122 may be applied to the entire surface of the top of the mini LED 121 including between the mini LEDs 121, but is not limited thereto. Referring to FIG. 2A , the OCR layer 122 ′ is a mini LED It may be applied only between the 121 , and referring to FIG. 2b , the OCR layer 122 ″ may be applied on the top of the mini LED 121 in the form of a convex lens.

The present invention promotes light diffusion by applying the OCR layer 122 between the mini LEDs 121, and improves the lattice mura and improves the light efficiency and reliability by applying the pattern sheet 130 on the mini LED 121. It is characterized by securing.

The OCR layer 122 is effective in preventing impact and oxidation of the mini LED 121, as well as improving extraction efficiency and lattice mura through refractive index matching (RI matching). When the OCR layer 122 is not disposed, it has an extraction efficiency of 92.4%, whereas when the OCR layer 122 is disposed, it can be seen that the extraction efficiency is about 95.6%.

In addition, the OCR layer 122 may prevent moisture permeation, thereby improving the reliability of the mini LED 121 .

The pattern sheet 130 is effective in improving lattice mura.

The pattern sheet 130 of the present invention may include a reflective pattern 132 provided in an area corresponding to the mini LED 121 . That is, the pattern sheet 130 according to the first embodiment of the present invention may include a base substrate 131 and a reflective pattern 132 disposed on at least one surface of the base substrate 131 . 1 illustrates an example in which the reflective pattern 132 is disposed on the lower surface of the base substrate 131 , but is not limited thereto, and the reflective pattern 132 may be disposed on the upper surface of the base substrate 131 , or the base. It may be disposed on both the upper and lower surfaces of the substrate 131 .

The base substrate 131 may have a thickness of about 10-50 μm, but is not limited thereto.

The reflective pattern 132 may be printed on the base substrate 131 by a screen printing method, for example, and may be made of a white reflective material, but is not limited thereto. An optical clear adhesive (OCA) for protecting the reflective pattern 132 and attaching it to the mini LED 121 may be coated on the upper surface of the reflective pattern 132 , but is not limited thereto. The OCA may have a thickness of about 10-25 μm.

When the reflective patterns 132 are disposed on both the upper and lower surfaces of the base substrate 131 , the reflective patterns 132 face each other and may be formed in a symmetrical shape. However, the present invention is not limited thereto, and the reflective patterns 132 may be formed in different shapes.

When the upper and lower reflection patterns 132 are designed asymmetrically, image quality may be further improved through fine adjustment.

The reflection pattern 132 may have a function of first refracting the light emitted from the mini LED 121 to distribute light distribution in a region in which the mini LED 121 is disposed and an area in which the mini LED 121 is not disposed.

The optical sheet 125 may include a fluorescent sheet 125a, a diffusion sheet 125b and a prism sheet 125c disposed on the fluorescent sheet 125a, but is not limited thereto.

The fluorescent sheet 125a may convert the color of light emitted from the mini LED 121 . For example, the light of the mini LED 121 or the micro LED is blue light (450 nm). In this case, the blue light needs to be converted into white light. The fluorescent sheet 125a may transmit blue light while simultaneously converting blue light into white light. The fluorescent sheet 125a may include a QD (Quantum Dot) sheet in addition to the fluorescent sheet using a fluorescent substance.

The diffusion sheet 125b may uniformly disperse the incident light.

The diffusion sheet 125b is formed by selecting at least one of a curable resin to which a light diffusion agent bead is added, for example, urethane acrylate, epoxy acrylate, ester acrylate, and radical generating monomers, either alone or mixed. Light diffusion can be caused by the light diffusing agent bead by applying the solution. However, the present invention is not limited thereto.

The prism sheet 125c may condense incident light using an optical pattern formed on its surface and emit it to the liquid crystal display panel 110 . The prism sheet 125c may have an optical pattern in the form of a triangular array having a generally inclined surface of 45° to improve luminance in the front direction, but is not limited thereto.

The design of the reflection pattern 132 of the present invention will be described with reference to FIG. 3 .

3 is a view for explaining a reflection pattern of the present invention.

4A to 4D are perspective views illustrating various shapes of a reflective pattern according to the present invention.

5A to 5E are views illustrating various arrangements of a reflective pattern according to the present invention.

Referring to FIG. 3 , the reflective pattern 132 according to the first embodiment of the present invention may include a plurality of patterns 132a1 and 132b1 .

The plurality of patterns 132a1 and 132b1 may include a plurality of central reflective patterns 132a1 positioned to correspond to the mini LED 121 and a plurality of sub-reflective patterns 132b1 positioned outside of the central reflective pattern 132a1. can

The sub-reflective pattern 132b1 may have a size equal to or larger than that of the central reflection pattern 132a1.

The plurality of sub-reflection patterns 132b1 may constitute a gradation pattern whose density decreases as the distance from the center increases.

The central reflection pattern 132a1 and the sub reflection pattern 132b1 may be formed in various shapes as shown in FIGS. 4A to 4D .

That is, the central reflective pattern 132a1 and the sub-reflective pattern 132b1 may include one of a hemispherical shape ( FIG. 4A ), a circular shape ( FIG. 4B ), a conical shape ( FIG. 4C ), and an inverted tapered shape ( FIG. 4D ).

At this time, although the central reflective pattern 132a1 and the sub-reflective pattern 132b1 shown in FIGS. 4A to 4D are circular when viewed from above, the present invention is not limited thereto and may be formed in a rectangular or oval shape when viewed from above.

The plurality of central reflective patterns 132a1 are positioned to correspond to the mini LED 121 and constitute the central pattern of the reflective pattern 132, and the plurality of sub-reflective patterns 132b1 are positioned outside the central pattern to form the reflective pattern ( 132) can be configured.

The central pattern may have a size of about 80-120% of the mini LED 121 .

In addition, the outer pattern may have a size in the range of +20% to -20% with respect to twice the total thickness (h1+h2) of the mini LED 121 and the OCR layer 122 .

The angle θ between the outside of the reflection pattern 132 and the mini LED 121 may have a value of 60°, but is not limited thereto.

The reflective pattern 132 shown in FIG. 3 exemplifies a case in which a plurality of central reflective patterns 132a1 are arranged in a rectangular shape and a plurality of sub reflective patterns 132b1 are arranged in a substantially circular shape. not limited

5A to 5E , the reflective pattern 132 of the present invention may have various arrangement shapes.

Referring to FIG. 5A , in the reflective pattern 132 , a plurality of central reflective patterns 132a2 may be arranged in a rhombus shape, and a plurality of sub reflective patterns 132b2 may be arranged in a rhombus shape.

Referring to FIG. 5B , in the reflective pattern 132 , a plurality of central reflective patterns 132a3 may be arranged in a rectangular shape, and a plurality of sub-reflective patterns 132b3 may be arranged in a hexagonal shape.

Referring to FIG. 5C , in the reflective pattern 132 , a plurality of central reflective patterns 132a4 may be arranged in a rectangular shape, and a plurality of sub-reflective patterns 132b4 may be arranged in a circular shape. In this case, the plurality of sub-reflective patterns 132b4 of FIG. 5C has a lower density than the plurality of sub-reflective patterns 132b1 of FIG. 3 , and the size of the central reflection pattern 132a4 and the sub-reflective pattern 132b4 is the same. characterized.

Referring to FIG. 5D , in the reflective pattern 132 , a plurality of central reflective patterns 132a5 may be arranged in a rectangular shape, and a plurality of sub-reflective patterns 132b5 may be arranged in a hexagonal shape. In this case, the plurality of central reflection patterns 132a5 of FIG. 5D has a smaller total area than the plurality of central reflection patterns 132a3 of FIG. 5B .

Referring to FIG. 5E , in the reflective pattern 132 , a plurality of central reflective patterns 132a6 may be arranged in a rhombus shape, and a plurality of sub reflective patterns 132b6 may be arranged in a rhombus shape. The central reflective pattern 132a6 and the sub-reflective pattern 132b6 of FIG. 5E have a smaller size than the central reflective pattern 132a2 and the sub-reflective pattern 132b2 of FIG. 5A, and are characterized in that they are arranged at a greater density. .

The liquid crystal display of the present invention can secure the performance of the mini LED without increasing the thickness of the backlight unit, that is, the liquid crystal display, which will be described in detail with reference to FIGS. 6A and 6B below.

6A and 6B are cross-sectional views illustrating a light diffusion distance according to a pitch between mini LED chips.

6A and 6B have substantially the same configuration as compared to the liquid crystal display 100 of FIG. 1 , except that the pattern sheet 130 and the OCR layer 122 are not provided.

The liquid crystal display of FIG. 6B shows a case in which the number of mini-LEDs 121 is reduced compared to FIG. 6A. In this case, as the pitch between the mini-LEDs 121 increases, the thickness of the product to secure the light diffusion distance d2 will increase That is, it can be seen that in the liquid crystal display of FIG. 6B , the light diffusion distance d2 increases from d1 to d2 compared to FIG. 6A , and thus the thickness of the liquid crystal display also increases.

Accordingly, in the liquid crystal display 100 according to the first embodiment of the present invention, the OCR layer 122 is applied between the mini LEDs 121 to promote light diffusion, and the pattern sheet 130 is formed on the mini LED 121 . ) to improve grating mura, improve light efficiency, and secure reliability. That is, the present invention can secure the performance of the mini LED 121 without increasing the thickness of the backlight unit, and provides effects of improving lattice mura, improving light efficiency, and securing reliability.

7 is a view showing a liquid crystal display to which various arrays of reflective patterns are applied.

8A to 8E are images showing image quality according to various arrangements of the reflection patterns of FIG. 7 .

FIG. 7 shows an example in which the above-described reflective patterns of various arrangement types are applied to an arbitrary area of the liquid crystal display.

That is, the reflective pattern of FIG. 5c is applied to the region A, the reflective pattern of FIG. 5d is applied to the B region, the reflective pattern of FIG. 5e is applied to the C region, and the reflective pattern of FIG. 3 is applied to the D region. taking as an example

8A shows the results of the comparative example to which the pattern sheet is not applied, FIG. 8B shows the results of area A, and FIG. 8C shows the results of area B. As shown in FIG. Also, FIG. 8D shows the results of the C region, and FIG. 8E shows the results of the D region.

Referring to FIG. 8A , in the case of the comparative example to which the pattern sheet is not applied, it can be seen that the lattice mura is clearly visible.

On the other hand, referring to FIGS. 8B to 8E , in the case of the example to which the pattern sheet is applied, it can be seen that the lattice mura is improved compared to the case of the comparative example of FIG. 8A , and in particular, in the case of FIGS. It was found that there was a significant improvement. That is, it can be seen that the grating mura is remarkably improved when the reflection pattern of FIGS. 5C and 3 is applied.

9A to 9D are images showing lattice mura according to application of a reflection pattern.

10A to 10G are images showing images according to the size and thickness of the reflection pattern.

9A shows the results of the comparative example to which the pattern sheet is not applied, and FIGS. 9B to 9D show the results of the example to which the pattern sheet of FIG. 3 is applied. In particular, FIGS. 9B to 9D are simulation results showing grating mura when the transmittance of the reflection pattern is applied to 55%, 55%, and 85%, respectively.

Referring to FIG. 9A , in the case of the comparative example to which the pattern sheet is not applied, it can be seen that the lattice mura is clearly visible.

On the other hand, referring to FIGS. 9B to 9D , in the case of the example to which the pattern sheet is applied, it can be seen that the lattice mura is improved compared to the case of the comparative example of FIG. occurs, and optimal results can be derived by taking this into account.

10A shows the results of the comparative example to which the pattern sheet is not applied, and FIGS. 10B to 10G show the results of the example to which the pattern sheet of FIG. 5C is applied. 10B to 10G show that the thickness of the reflection pattern is 20, 30, 50, 20, 30 and 50 μm, respectively, and the size is 0.63R, 0.63R, 0.63R, 0.85R, 0.85R, and 0.85R, respectively. It shows the image of the burn of

When the luminance of the comparative example of Fig. 10a is 100% (8,665 nit), in the case of the embodiment of Figs. 10b to 10g, the luminance is 82.8% (7,175 nit), 76.9% (6,645 nit), 76.7% (6,648 nit), It can be seen that they decrease to 78.4% (6,797 nit), 75.1% (6,506 nit) and 72.8% (6,310 nit), respectively.

In the case of the comparative example of FIG. 10A, the stain was reduced to 4 levels, but in the examples of FIGS. 10B to 10G, the stain was reduced to 3, 2, 2, 3.5, 3.5, and 3.5 levels, respectively.

In particular, it can be seen that the lattice mura is effectively improved in the case of FIG. 10D to which a pattern sheet having a thickness of 50 μm and a size of 0.63R of the reflection pattern is applied.

Meanwhile, as described above, the reflective pattern of the present invention may be disposed on the upper surface of the base substrate or may be disposed on both the upper and lower surfaces of the base substrate, which will be described in detail with reference to the drawings.

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

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

11 and 12 , the liquid crystal displays 200 and 300 according to the second and third embodiments of the present invention have only the configuration of the reflective sheets 230 and 330 compared to the liquid crystal display 100 of FIG. 1 . This is only different, and since other configurations are substantially the same, a redundant description will be omitted. The same reference numerals are used for the same components.

11 and 12 , the liquid crystal display devices 200 and 300 according to the second and third embodiments of the present invention include the liquid crystal display panel 110 and the liquid crystal display panel ( 110) may include a backlight unit for providing light.

The backlight unit includes the light source unit 120 disposed inside the lower cover 145 , the pattern sheets 230 and 330 disposed on the light source unit 120 , and the optical sheet disposed on the pattern sheets 230 and 330 . (125).

In this case, the pattern sheet 230 according to the second embodiment of the present invention may include a base substrate 231 and a reflective pattern 233 disposed on the upper surface of the base substrate 231 .

In addition, the pattern sheet 330 according to the third exemplary embodiment of the present invention may include a base substrate 331 and reflective patterns 332 and 333 disposed on upper and lower surfaces of the base substrate 331 .

The reflective patterns 332 and 333 may include a first reflective pattern 332 and a second reflective pattern 333 respectively disposed on a lower surface and an upper surface of the base substrate 331 .

The base substrates 231 and 331 may have a thickness of about 10-50 μm, but is not limited thereto.

The reflective patterns 232 , 332 , and 333 may be printed on the base substrates 231 and 331 by, for example, screen printing, and may be made of a white reflective material, but is not limited thereto. An optical clear adhesive (OCA) for protecting the reflective patterns 232 , 332 , and 333 and attaching to the mini LED 121 may be coated on the upper surfaces of the reflective patterns 232 , 332 , and 333 , but is not limited thereto. The OCA may have a thickness of about 10-25 μm.

As in the third embodiment of the present invention, when the first reflective pattern 332 and the second reflective pattern 333 are respectively disposed on the lower and upper surfaces of the base substrate 331 , the first reflective pattern 332 and the second reflective pattern 332 are The two reflective patterns 333 face each other and may be formed in a symmetrical shape. However, the present invention is not limited thereto, and the first reflective pattern 332 and the second reflective pattern 333 may be formed to have different shapes.

When the first reflection pattern 332 and the second reflection pattern 333 are designed asymmetrically, image quality may be further improved through fine adjustment.

On the other hand, the reflective sheet of the present invention can maintain a certain gap between the mini LED and the mini LED, and in this case, the reflection can be maximized, thereby improving the image quality, which will be described in detail with reference to FIG. 13 .

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

The liquid crystal display 400 of FIG. 13 is different from the liquid crystal display 100 of FIG. 1 only in that a gap is formed between the reflective sheet 130 and the mini LED 121 through the adhesive layer 435. , and other configurations are substantially the same, so a redundant description is omitted. The same reference numerals are used for the same components.

Referring to FIG. 13 , the liquid crystal display 400 according to the fourth embodiment of the present invention includes a liquid crystal display panel 110 on which an image is displayed and a backlight disposed below the liquid crystal display panel 110 to provide light. may contain units.

The backlight unit includes the light source unit 120 disposed inside the lower cover 145 , the pattern sheet 130 disposed on the light source unit 120 , and the optical sheet 125 disposed on the pattern sheet 130 . may include

In this case, the pattern sheet 130 according to the fourth embodiment of the present invention may include a base substrate 131 and a reflective pattern 132 disposed on a lower surface of the base substrate 131 . However, the present invention is not limited thereto, and the reflective pattern 132 may be disposed on the upper surface of the base substrate 131 , or may be disposed on both the upper and lower surfaces of the base substrate 131 .

In the case of the fourth embodiment of the present invention, the OCR layer 422 may be applied only between the mini LEDs 121, but is not limited thereto. The OCR layer 422 may be applied to the entire surface of the top of the mini LED 121 including between the mini LEDs 121 , or may be applied to the top of the mini LED 121 in the form of a convex lens.

In addition, in the case of the fourth embodiment of the present invention, an adhesive layer 435 having a predetermined thickness is interposed between the OCR layer 422 on which the mini LED 121 is not disposed and the base substrate 131 , so that the reflective sheet 130, that is, It is characterized in that an air gap is formed between the reflective pattern 132 and the mini LED 121 . By securing an air gap in front of the mini LED 121 , reflection due to a difference in refractive index between the two media can be maximized, thereby improving image quality. That is, since the air layer has a relatively large refractive index of 1, it is possible to increase the reflectance by the reflective pattern 132 .

The adhesive layer 435 may serve to prevent the pattern sheet 130 from flowing.

Meanwhile, in the present invention, a reflective sheet may be added between the mini LEDs, a protective layer and a photo solder resist (PSR) may be added, which will be described in detail with reference to FIG. 14 .

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

The liquid crystal display 500 of FIG. 14 is different from the liquid crystal display 100 of FIG. 1 only in that a protective layer 536 and a photo solder resist 537 are added between the mini LEDs 121 . , and other configurations are substantially the same, so a redundant description is omitted. The same reference numerals are used for the same components.

Referring to FIG. 14 , the liquid crystal display 500 according to the fifth embodiment of the present invention includes a liquid crystal display panel 110 on which an image is displayed and a backlight disposed below the liquid crystal display panel 110 to provide light. may contain units.

The backlight unit includes the light source unit 120 disposed inside the lower cover 145 , the pattern sheet 130 disposed on the light source unit 120 , and the optical sheet 125 disposed on the pattern sheet 130 . may include

In this case, the fifth embodiment of the present invention is characterized in that a protective layer 536 and a photo-solder resist 537 are disposed on the printed circuit board 123 between the mini LEDs 121 .

The protective layer 536 is disposed on the printed circuit board 123 to a thickness of about 100 μm, and may serve to protect the mini LED 121 . The protective layer 536 may have a black color, but is not limited thereto.

When disposing the protective layer 536 , a gap of at least 5 mm may be left between the mini LEDs 121 .

The photo-solder resist 537 may be disposed on the passivation layer 536 in order to improve reflectance reduction caused by the passivation layer 536 , and white color may be applied thereto.

In order to prevent bending of the printed circuit board 123 due to the protective layer 536, a warpage prevention layer 526 with a thickness of about 100 μm may be disposed between the printed circuit board 123 and the lower cover 145, but this not limited

Meanwhile, in order to improve image quality and maximize efficiency, a reflective sheet may be applied between the mini LEDs 121 instead of the protective layer 536 and the photo-solder resist 537 .

Liquid crystal displays according to embodiments of the present invention may be described as follows.

A liquid crystal display device according to an embodiment of the present invention includes a liquid crystal display panel on which an image is displayed, a plurality of mini-LEDs disposed under the liquid crystal display panel to provide light, and a resin layer disposed between the plurality of mini-LEDs. and a pattern sheet disposed between the liquid crystal display panel and the plurality of mini-LEDs and having a reflective pattern on at least one surface, wherein the reflective pattern includes a plurality of central reflective patterns positioned corresponding to the mini-LEDs and the It may be composed of a plurality of sub-reflection patterns positioned outside the central reflection pattern.

According to another feature of the present invention, the liquid crystal display may further include a printed circuit board disposed under the plurality of mini-LEDs to mount the plurality of mini-LEDs.

According to another feature of the present invention, the resin layer may be composed of an optical clear resin (OCR) layer.

According to another feature of the present invention, the resin layer may be disposed on the entire surface of the mini-LED, including between the mini-LEDs.

According to another feature of the present invention, the resin layer may be disposed only between the mini LEDs.

According to another feature of the present invention, the pattern sheet may include a base substrate and the reflective pattern disposed on at least one surface of the base substrate.

According to another feature of the present invention, the reflective pattern may include a first reflective pattern disposed on a lower surface of the base substrate and a second reflective pattern disposed on an upper surface of the base substrate.

According to another feature of the present invention, the first reflective pattern and the second reflective pattern may face each other and have a symmetrical shape.

According to another feature of the present invention, the first reflective pattern and the second reflective pattern may have different shapes.

According to another aspect of the present invention, the liquid crystal display device further includes an optical sheet disposed between the liquid crystal display panel and the pattern sheet, wherein the optical sheet includes a fluorescent sheet disposed on the reflective sheet and the fluorescent sheet It may include a diffusion sheet sequentially disposed on the diffusion sheet and a prism sheet disposed on the diffusion sheet.

According to another feature of the present invention, the sub-reflective pattern may have a size equal to or larger than that of the central reflection pattern.

According to another feature of the present invention, the plurality of sub-reflection patterns may constitute a gradation pattern such that the density decreases as the distance from the center increases.

According to another feature of the present invention, the central reflection pattern and the sub-reflection pattern may have a hemispherical shape, a circular shape, a conical shape, or a reverse tapered shape.

According to another feature of the present invention, the plurality of central reflective patterns constitute a central pattern of the reflective pattern, and the plurality of sub-reflective patterns are located outside the central pattern to constitute an outer pattern of the reflective pattern, , the central pattern may have a size of 80-120% of the mini-LED.

According to another feature of the present invention, the outer pattern may have a size in the range of +20% to -20% with respect to twice the total thickness of the mini LED and the resin layer.

According to another feature of the present invention, the plurality of central reflective patterns may be arranged in a rectangular shape, and the plurality of sub-reflective patterns may be arranged in a circular shape.

According to another feature of the present invention, an air gap may be formed between the reflective sheet and the plurality of mini LEDs.

According to another feature of the present invention, the liquid crystal display may further include an adhesive layer interposed between the base substrate and the resin layer on which the plurality of mini LEDs are not disposed.

According to another feature of the present invention, the liquid crystal display may further include a protective layer disposed between the plurality of mini LEDs and a white photo solder resist (PSR) disposed on the protective layer.

According to another feature of the present invention, the liquid crystal display may further include a reflective sheet disposed on the printed circuit board between the plurality of mini LEDs.

Although the embodiments of the present invention have been described in more detail with reference to the accompanying drawings, the present invention is not necessarily limited to these embodiments, and various modifications may be made within the scope without departing from the technical spirit of the present invention. . Therefore, the embodiments disclosed in the present invention are not intended to limit the technical spirit of the present invention, but to illustrate, and the scope of the technical spirit of the present invention is not limited by these embodiments. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive. The protection scope of the present invention should be construed by the following claims, and all technical ideas within the scope equivalent thereto should be construed as being included in the scope of the present invention.

100, 200, 300, 400, 500: liquid crystal display device
110: liquid crystal display panel
120: light source unit
121: mini LED
122, 122', 122", 422: OCR layer
123: printed circuit board
125: optical sheet
130, 230, 330: pattern sheet
131, 231, 331: base substrate
132, 232, 332, 333: reflection pattern
140: panel guide
145: lower cover
435: adhesive layer
526: warpage prevention layer
536: protective layer
537: photo solder resist

Claims (20)

a liquid crystal display panel on which an image is displayed;
a plurality of mini LEDs disposed under the liquid crystal display panel to provide light;
a resin layer disposed between the plurality of mini LEDs; and
and a pattern sheet disposed between the liquid crystal display panel and the plurality of mini LEDs and having a reflective pattern on at least one surface thereof,
The reflective pattern includes a plurality of central reflective patterns positioned to correspond to the mini-LED and a plurality of sub-reflective patterns positioned outside the central reflective pattern. The method of claim 1,
The liquid crystal display device of claim 1, further comprising a printed circuit board disposed under the plurality of mini-LEDs to mount the plurality of mini-LEDs. The method of claim 1,
The resin layer is composed of an optical clear resin (OCR) layer, the liquid crystal display device. The method of claim 1,
The resin layer is disposed on the front surface of the mini-LED, including between the mini-LEDs. The method of claim 1,
and the resin layer is disposed only between the mini LEDs. The method of claim 1,
The pattern sheet,
base substrate; and
and the reflective pattern disposed on at least one surface of the base substrate. 7. The method of claim 6,
The reflective pattern is
a first reflective pattern disposed on a lower surface of the base substrate; and
and a second reflective pattern disposed on an upper surface of the base substrate. 8. The method of claim 7,
The first reflective pattern and the second reflective pattern face each other and have a symmetrical shape. 8. The method of claim 7,
and the first reflection pattern and the second reflection pattern have different shapes. The method of claim 1,
Further comprising an optical sheet disposed between the liquid crystal display panel and the pattern sheet,
The optical sheet,
a fluorescent sheet disposed on the reflective sheet;
a diffusion sheet sequentially disposed on the fluorescent sheet; and
and a prism sheet disposed on the diffusion sheet. The method of claim 1,
The sub-reflection pattern has a size equal to or greater than a size of the central reflection pattern. The method of claim 1,
The plurality of sub-reflection patterns constitutes a gradation pattern such that the density decreases as the distance from the center increases. The method of claim 1,
The central reflection pattern and the sub-reflection pattern have a hemispherical shape, a circular shape, a conical shape, or an inverted tapered shape. The method of claim 1,
The plurality of central reflective patterns constitute a central pattern of the reflective pattern, and the plurality of sub-reflective patterns are located outside the central pattern to constitute an outer pattern of the reflective pattern,
The central pattern has a size of 80-120% of the mini-LED, liquid crystal display. 15. The method of claim 14,
The outer pattern has a size in the range of +20% to -20% with respect to twice the total thickness of the mini LED and the resin layer. The method of claim 1,
The plurality of central reflection patterns are arranged in a rectangular shape, and the plurality of sub-reflective patterns are arranged in a circular shape. 7. The method of claim 6,
An air gap is formed between the reflective sheet and the plurality of mini LEDs. 18. The method of claim 17,
The liquid crystal display device of claim 1, further comprising an adhesive layer interposed between the resin layer on which the plurality of mini-LEDs are not disposed and the base substrate. The method of claim 1,
a protective layer disposed between the plurality of mini LEDs; and
The liquid crystal display device of claim 1, further comprising a white photo solder resist (PSR) disposed on the passivation layer. 3. The method of claim 2,
and a reflective sheet disposed on the printed circuit board between the plurality of mini LEDs.

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