KR20220008059A - Direct Type Back Light Unit - Google Patents

Abstract

The present invention relates to a direct-type backlight unit. According to the present invention, the backlight unit comprises: a film having a light transmissive property; an LED emitting light on a location spaced apart from the film at an arbitrary distance; a substrate in which a plurality of LEDs are mounted; and a plurality of light control units disposed on one side of the film to correspond to each of the plurality of LEDs and provided with a light diffuser transmitting or diffusing light and a light reflector reflecting light. Accordingly, the present invention can increase a degree of uniformity of the backlight unit.

Description

Direct Type Back Light Unit

The present invention relates to a direct backlight unit for improving the uniformity of brightness.

Recently, as the information society develops, the demand for display devices is also increasing in various forms. In particular, liquid crystal displays (hereinafter referred to as 'LCD') have excellent image quality and are lightweight, thin, and low power consumption. For this reason, it is widely used not only in portable flat panel displays, but also in laptops, computer monitors, and monitors of various imaging devices that require large-area and high-quality images.

However, since such an LCD does not emit light by itself, a separate external light source is essential to realize a high-quality image. Accordingly, the structure of the LCD further includes a backlight unit as a light source of the liquid crystal display panel in addition to the liquid crystal display panel, so that the backlight unit uniformly supplies a high-brightness light source to the LCD panel, thereby realizing a high-quality image.

As a light source for backlight or illumination for flat panel display devices such as LCD, it is an element for a flat lamp that has high luminance and can display various colors. Diode) devices, CCFL (Cold Cathode Fluorescent Lamp), HCFL (Hot Cathode Fluorescent Lamp), EEFL (External Electrode Fuorescent Lamp), etc. are widely used.

Depending on the location of the LED light source, a bright part and a relatively dark part are generated in the overall diffusion plate, and the luminance and the uniformity of the luminance are deteriorated. In order to solve this problem, a plurality of diffusion sheets may be further provided where the diffusion plate is located, or the diffusion plate may be disposed by increasing the distance from the light source, but in this case, the thickness of the backlight increases.

Therefore, in a direct-type backlight unit using an LED as a light source, the light emitted from the light source is efficiently reflected, and the light that is not completely incident from the diffuser plate is partially reflected back to the diffuser plate, thereby improving the luminance and luminance uniformity. An efficient direct type backlight unit is required.

Republic of Korea Patent Registration No. 10-0727856

SUMMARY OF THE INVENTION It is an object of the present invention to solve the problems of the related art, and to provide a direct type backlight unit capable of improving uniformity of brightness by resolving a difference in shading.

A direct type backlight unit according to an embodiment of the present invention for achieving the above object includes: a film having light transmittance; an LED spaced apart from the film by an arbitrary interval and emitting light toward the film; a substrate on which a plurality of the LEDs are mounted, and an electric circuit pattern electrically connected to the LEDs is provided; and a light diffuser positioned between the LED and the film, disposed on one side of the film to correspond to each of the plurality of LEDs, and reflected toward the substrate and a light diffuser that transmits or diffuses the light emitted from the LED It may be characterized as including; a light control unit provided with a light reflector.

Here, each of the plurality of LEDs may have a smaller diameter or width than the corresponding light control unit as another feature.

Here, in the light control unit. Another feature may be that a spaced region is provided between a portion that transmits or diffuses the light emitted from the LED and a portion that reflects the light toward the substrate.

Here, another feature may be that, in the light control unit, a plurality of light reflectors that reflect the light emitted from the LED are provided in a form that is separated from each other and separated from each other.

Here, a light reflector that reflects the light emitted from the LED is positioned on the central center of the light control unit, and the light diffuser that transmits or diffuses the light emitted from the LED reflects the light emitted from the LED. Another feature may be that it is arranged in a form surrounding the light reflector.

Here, the light control unit may be formed on one side of the film by a screen printing method using an ink including a light diffusion material or a light reflection material as another feature.

Here, the plurality of LEDs may be spaced apart from each other by a predetermined interval and disposed on the substrate as another feature.

Here, the plurality of light control units disposed on the film may be further characterized as being spaced apart from each other by a predetermined interval.

Direct type backlight unit according to another embodiment of the present invention for achieving the above object, the light-transmitting film; an LED spaced apart from the film by an arbitrary interval and emitting light toward the film; a substrate on which a plurality of the LEDs are mounted, and an electric circuit pattern electrically connected to the LEDs is provided; and a light reflector positioned between the LED and the film, disposed on one side of the film to correspond to each of the plurality of LEDs, and reflecting the light emitted from the LED toward the substrate, the size corresponding to the LED It may be characterized as including; a light control unit provided as

Here, in one of the light control units, a plurality of light reflectors that reflect the light emitted from the LED toward the substrate are provided so that they can be distinguished from each other, and the plurality of light reflectors have a central point in the center of the light control unit. It may be characterized by having an arrangement with a center of symmetry as another feature.

The direct-type backlight unit according to an embodiment of the present invention has the effect of increasing the brightness uniformity of the backlight unit because it suppresses the occurrence of a shade difference within the backlight unit.

1 is a perspective view schematically illustrating a direct type backlight unit (BLU) according to an embodiment of the present invention.
2 is a side view schematically illustrating a side of a direct type backlight unit according to an embodiment of the present invention.
3 is a plan view schematically illustrating a light control unit of a direct type backlight unit according to an embodiment of the present invention.
4 and 5 are plan views schematically showing an applied form of a light control unit in a direct type backlight unit according to an embodiment of the present invention.
6 is a plan view schematically illustrating a light control unit of a direct type backlight unit according to another embodiment of the present invention.
7 is a plan view schematically showing another form of a light control unit in a direct type backlight unit according to another embodiment of the present invention.

Hereinafter, a preferred embodiment will be described with reference to the accompanying drawings so that the present invention may be understood in more detail.

Since the present invention can have various changes and can have various embodiments, specific embodiments are illustrated in the drawings and described in detail. However, this is not intended to limit the present invention to specific embodiments, and it should be understood to include all modifications, equivalents and substitutes included in the spirit and scope of the present invention.

Terms such as first, second, etc. may be used to describe various elements, but the elements should not be limited by the terms. The above terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, a first component may be referred to as a second component, and similarly, a second component may also be referred to as a first component. and/or includes a combination of a plurality of related listed items or any of a plurality of related listed items.

When an element is referred to as being “connected” or “connected” to another element, it is understood that it may be directly connected or connected to the other element, but other elements may exist in between. it should be On the other hand, when it is said that a certain element is "directly connected" or "directly connected" to another element, it should be understood that the other element does not exist in the middle.

The terms used in the present application are only used to describe specific embodiments, and are not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly dictates otherwise. In the present application, terms such as “comprise” or “have” are intended to designate that a feature, number, step, operation, component, part, or combination thereof described in the specification exists, but one or more other features It should be understood that this does not preclude the existence or addition of numbers, steps, operations, components, parts, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical and scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in a commonly used dictionary should be interpreted as having a meaning consistent with the meaning in the context of the related art, and should not be interpreted in an ideal or excessively formal meaning unless explicitly defined in the present application. does not

Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to the accompanying drawings. In describing the present invention, in order to facilitate the overall understanding, the same reference numerals are used for the same components in the drawings, and duplicate descriptions of the same components are omitted.

1 is a perspective view schematically showing a direct type backlight unit according to an embodiment of the present invention, and FIG. 2 is a side view schematically showing a side surface of a direct type backlight unit according to an embodiment of the present invention.

1 and 2 , a direct type backlight unit according to an embodiment of the present invention includes a light-transmitting film 300 , an LED 200 , a substrate 100 and a light control unit 400 . include

The light-transmitting film 300 is a film 300 made of a transparent plastic material, and may be made of a material such as PMMA (polymethyl methacrylate), PC (Polycarbonate), PET (Polyethylene terephthalate), PS (polystyrene). .

The film 300 is spaced apart from the substrate 100 on which the LED 200 is mounted at a predetermined interval, and supports a plurality of light control units 400 disposed on one side.

The LED 200 is spaced apart from the film 300 by an arbitrary interval, and is mounted on the substrate 100 to receive support from the substrate 100 . The LED 200 receives power through an electric circuit pattern provided on the substrate 100 and emits light toward the film 300 .

In addition, the plurality of LEDs 200 are spaced apart from each other by a predetermined interval and disposed on the substrate 100 .

A plurality of LEDs 200 are mounted on the substrate 100 . In addition, an electric circuit pattern electrically connected to the plurality of LEDs 200 is provided on the substrate 100 .

And the substrate 100 on which the LED 200 is mounted is spaced apart from the film 300 by a predetermined interval, and a spacer (not shown) may be disposed between the substrate 100 and the film 300 to set the interval. .

On one side of the substrate 100 on which the LED 200 is mounted, a plurality of LEDs 200 are spaced apart from each other at a predetermined interval, and between one LED 200 and another LED 200 adjacent thereto. It is preferable that a reflecting material is provided in the part.

The light control unit 400 is positioned between the plurality of LEDs 200 and the film 300 , and a plurality of light control units are disposed on one side of the film 300 to correspond to each of the plurality of LEDs 200 .

The plurality of light control units 400 disposed on the film 300 may be disposed to be spaced apart from each other by a predetermined interval.

In addition, the light control unit 400 is provided with a light diffuser that transmits or diffuses the light emitted from the LED 200 and a light reflector that reflects the light toward the substrate 100 .

The light control unit 400 includes a modified acrylic resin, a light diffusion material, and a light reflection material. That is, the light diffuser of the light control unit 400 may include a modified acrylic resin and a light diffusion material, and the light reflector of the light control unit 400 may include a modified acrylic resin and a light reflection material. .

A plastic bead or silica may be used as the light diffusion material, and titanium dioxide (TiO 2 ) may be used as the light reflection material.

As the modified acrylic resin, a heat-drying type, a thermosetting type UV-curing type acrylic resin may be used.

The light control unit 400 may be formed on one side of the film 300 by a screen printing method. The light control unit 400 can be formed through a method of screen printing on one side of the film 300 using an ink including a light diffusion material or a light reflection material. When screen printing is used, it is possible to obtain an advantage that the printing uniformity of the light control unit 400 printed on the surface of the film 300 can be secured.

In addition, since the material of the light reflector portion and the light diffuser portion in the light control unit 400 is different, as a form of printing by screen printing, 2nd printing or 3rd printing may be applied.

With respect to the size of the light control unit 400 and the LED 200 , each of the plurality of LEDs 200 is preferably smaller in diameter or width than the corresponding light control unit 400 . In other words, it is preferable that the width or diameter of the light control unit 400 is equal to or larger than that of the corresponding LED 200 . Accordingly, the light control unit 400 may have a width or diameter that is 2-3 times greater than the width or diameter of the LED 200 .

and in the light control unit 400 . It is preferable that a spaced region is provided between the light diffuser, which is a portion that transmits or diffuses the light emitted from the LED 200 and the light reflector 410 that reflects the light toward the substrate 100 .

Here, further reference will be made to FIG. 3 . 3 is a plan view schematically illustrating a light control unit of a direct type backlight unit according to an embodiment of the present invention.

As shown in FIG. 3 , the light reflector 410 is positioned at the center of one light control unit 400 , and the light diffuser 430 is formed in the form of a ring surrounding the periphery of the light reflector 410 . is placed. In addition, a spaced portion 420 is provided between the light reflector 410 and the light diffuser 430 .

A portion of the light emitted from the LED 200 through the spaced area 420 may pass through the film 300 and travel straight. In addition, the light reflector 410 reflects the light emitted from the LED 200 , and the light diffuser 430 diffuses the light emitted from the LED 200 .

Accordingly, it is possible to suppress the occurrence of a region having relatively low brightness between one LED 200 and another LED 200 adjacent thereto.

In addition, in the light control unit 400 , it is also preferable that a plurality of light reflectors 410 , which are portions that reflect the light emitted from the LED 200 , are provided in a form that is separated from each other and separated from each other. Here, further reference will be made to FIGS. 4 and 5 .

4 and 5 are plan views schematically showing an applied form of a light control unit in a direct backlight unit according to an embodiment of the present invention.

First, as shown in FIG. 4 , in one light control unit 401 , a light reflector 410 is positioned at a central central point CP. In addition, the light reflector 412 is further disposed after the area 420 spaced apart from the center point CP by a predetermined interval in the outward direction. In addition, the light diffuser 430 is disposed next to the area 422 spaced apart from each other by a predetermined interval in the outward direction.

As such, in the light control unit 401, a portion that reflects the light emitted from the LED 200 is located at the central point CP of the light control unit 401, and the light emitted from the LED 200 is A portion that transmits or diffuses may be disposed to surround a portion that reflects light emitted from the LED 200 .

As described above, with respect to the central point CP of the light control unit 401, the regions 410 where light is reflected, regions 420 and 422 through which light is transmitted, and regions 430 where light is diffused are formed toward the outside with respect to the central point CP. It is also preferable that the light control units 401 are formed so that they appear sequentially.

On the other hand, the shape of the light control unit 402 as referenced in FIG. 5 is also possible.

Referring to FIG. 5 , a light reflector 410 is disposed at a central point CP of the light control unit 402, and a plurality of light reflectors 414 with the light reflector 410 disposed in the center as a symmetric center. and the light diffuser 434 are arranged in a radial form.

Light diffusers 434 are disposed on both sides with one light reflector 414 interposed therebetween, and are spaced apart (427) at a certain angle between the neighboring light diffusers 434 and light reflectors 414. have.

Alternatively, the light reflector 414 and the light diffuser 434 are alternately arranged with each other, and the light reflector 410 positioned at the center point CP is said to be sequentially arranged in a clockwise or counterclockwise direction. may be

As such, the arrangement or arrangement of the plurality of light reflectors 414 and light diffusers 434 can also increase the brightness uniformity of the direct backlight unit. Here, the area of one light reflector 414 and the area of one light diffuser 434 may be formed to be equal to each other, and if necessary, the area of the light reflector 414 is the area of the light diffuser 434 It may be formed to be larger or, conversely, the area of the light reflector 414 may be formed to be smaller than the area of the light diffuser 434 .

For reference, although some exemplary shapes of the light control unit 400 according to an embodiment of the present invention are shown through FIGS. 3 to 5 , the shape in which the light diffuser is disposed at the central point of the light control unit 400 is also It should be noted that it is sufficiently possible and does not exclude this form.

On the other hand, a direct-type backlight unit according to another embodiment is also sufficiently possible as follows. A direct type backlight unit according to another embodiment of the present invention includes a film 300 , an LED 200 , a substrate 100 , and a light control unit 400 , wherein the film 300 , the LED 200 , and the substrate (100) is the same as described above.

The light control unit 400 is located between the LED 200 and the film 300, but is disposed on one side of the film 300 so as to correspond to each of the plurality of LEDs 200, and the light emitted from the LED 200 A portion that reflects the light toward the substrate 100 is provided with a size corresponding to the LED 200 .

Here, it will be described with further reference to FIGS. 6 and 7 .

6 is a plan view schematically showing a light control unit of a direct type backlight unit according to another embodiment of the present invention, and FIG. 7 is another view of the light control unit 400 in the direct type backlight unit according to another embodiment of the present invention. It is a plan view schematically showing the shape.

As shown in FIG. 6 , a form in which one light reflector 410 is provided as the light control unit 403 is also possible. In this case, the size of the light control unit 400 may be formed to have a larger width or diameter than that of the LED 200 . For example, it can be about twice the size.

Since the light control unit 403 reflects the light emitted from the LED 200, it is possible to suppress the occurrence of shading between the LED 200 and the LED 200 so that the overall brightness of the backlight unit is uniform. have.

In addition, as a more applied form, in one light control unit, a plurality of light reflectors, which reflect the light emitted from the LED 200 toward the substrate 100, are provided so that they can be distinguished. The reflector may have an arrangement shape with the central point CP of the light control unit 400 as a symmetrical center.

7, one light reflector 410 is disposed in the center of one light control unit 404, and another light reflector 416 is divided around the light reflector 410 as the center. can be placed. Preferably, a plurality of light reflectors 416 are disposed to have a radial shape with the center CP of the light control unit 404 as a symmetric center.

Such a light control unit 404 is also preferable because it can suppress the occurrence of shadows between the LED 200 and the LED 200 .

As such, the direct backlight unit according to the present invention is a light source unlike the conventional method, that is, the amount of light is lost and the light uniformity is low due to the method of shielding the light emitted from the LED 200 without considering reflection and diffusion of light. The part can induce reflection to exhibit a shielding effect and at the same time disperse light between the light source and the light source.

Accordingly, by diffusing or scattering the light dispersed between the light source and the light source, it is possible to suppress the difference in the amount of light from the light source and suppress the dark portion, thereby improving the overall light uniformity of the backlight unit.

As described above, according to the direct type backlight unit according to the present invention, there is an advantage in that the uniformity of the brightness of the backlight unit can be increased by suppressing the occurrence of a shadow difference.

As described above, the detailed description of the present invention has been made by the embodiments with reference to the accompanying drawings, but since the above-described embodiments have only been described with reference to the preferred embodiments of the present invention, the present invention It should not be construed as being limited only to the embodiments, and the scope of the present invention should be understood as the following claims and their equivalents.

100: substrate 200: LED
300: film 400: light control unit
410: light reflector 430: light diffuser
CP: center point of light control unit

Claims (10)

a film that is transparent to light;
an LED spaced apart from the film by an arbitrary interval and emitting light toward the film;
a substrate on which a plurality of the LEDs are mounted and provided with an electric circuit pattern electrically connected to the LEDs; and
It is located between the LED and the film, and is disposed on one side of the film so as to correspond to each of the plurality of LEDs, and a light diffuser that transmits or diffuses the light emitted from the LED and reflects it toward the substrate A direct-type backlight unit comprising a; a light control unit provided with a light reflector.
The method of claim 1,
Each of the plurality of LEDs is a direct backlight unit, characterized in that the diameter or width is smaller than that of the corresponding light control unit.
3. The method of claim 2,
in the light control unit.
A direct backlight unit, characterized in that a spaced region is provided between a light diffuser that transmits or diffuses the light emitted from the LED and a light reflector that reflects it toward the substrate.
4. The method of claim 3,
In the light control unit,
A direct type backlight unit, characterized in that a plurality of light reflectors that reflect the light emitted from the LED are provided in a form separated from each other and separated from each other.
4. The method of claim 3,
A light reflector that reflects the light emitted from the LED is located on the central center of the light control unit,
A light diffuser that transmits or diffuses the light emitted from the LED,
A direct-type backlight unit, characterized in that it is disposed in a shape surrounding a light reflector that reflects the light emitted from the LED.
4. The method of claim 3,
The light control unit,
A direct type backlight unit, characterized in that it is formed on one side of the film by a screen printing method using an ink containing a light diffusing material or a light reflecting material.
7. The method of claim 6,
A plurality of the LEDs are spaced apart from each other at a predetermined distance and disposed on the substrate.
8. The method of claim 7,
The plurality of light control units disposed on the film are spaced apart from each other at a predetermined interval,
Direct type backlight unit.
a film that is transparent to light;
an LED spaced apart from the film by an arbitrary interval and emitting light toward the film;
a substrate on which a plurality of the LEDs are mounted and provided with an electric circuit pattern electrically connected to the LEDs; and
Located between the LED and the film, a plurality of light reflectors are disposed on one side of the film to correspond to each of the plurality of LEDs, and a light reflector that reflects the light emitted from the LED toward the substrate has a size corresponding to the LED. Direct type backlight unit comprising a; provided light control unit.
10. The method of claim 9,
In one of the light control units,
A plurality of light reflectors that reflect the light emitted from the LED toward the substrate are provided so that they can be distinguished from each other, and the plurality of light reflectors are arranged in a symmetrical configuration with the central point of the light control unit as a symmetrical center. direct backlight unit.

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