KR101823675B1 - Back light umit within resin layer for light-guide, method of manufacuring the same and LCD using the same - Google Patents

Abstract

The present invention relates to a backlight unit, comprising: a plurality of LED light sources formed on a printed circuit board; a resin layer stacked on the printed circuit board to diffuse and guide light emitted from the LED light sources forward; And a capsule portion for sealing the resin layer and forming a space separated from the resin layer.
According to the present invention, there is provided a light emitting device, comprising: a resin layer; a light guide plate; a backlight unit; and a capsule portion sealing the peripheral portion of the LED to form a space with the resin layer. So that the heat dissipation characteristics can be improved.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a backlight unit, a method of manufacturing the same, and a liquid crystal display including the same,

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a backlight unit capable of reducing the structure of a light guide plate to make a structure of a backlight unit thin and ensuring light efficiency, and a liquid crystal display using the same.

BACKGROUND ART A liquid crystal display (LCD) is a display device capable of adjusting a desired image by separately supplying a data signal according to image information to pixels arranged in a matrix form and controlling the light transmittance of the pixels, Since it can not emit light, it is designed so that a back-light unit can be installed on the back surface to express an image.

1A, the backlight device 1 includes a substrate 20 on which a planar light guide plate 30 is disposed, and a plurality of side-type LEDs 10 (only one is shown) .

The light L incident on the light guide plate 30 from the LED 10 is reflected by the reflective sheet 40 in a fine reflection pattern provided on the bottom surface of the light guide plate 30 and is emitted from the light guide plate 30, 30 to provide a backlight to the LCD panel 50 on the upper side. 1B, a plurality of optical elements such as a diffusion sheet 31, prism sheets 32 and 33, and a protective sheet 34 are interposed between the light guide plate 30 and the LCD panel 50, And a sheet may be further added.

The backlight unit functions to illuminate the backlight unit uniformly so that the display image can be seen on the rear surface of the LCD, which can not emit light itself. The light guide plate is a part that performs the lighting function uniformly with the brightness of the backlight unit. It is one of the plastic molding lenses that uniformly transmits the diverging light to the entire LCD surface. Therefore, such a light guide plate is basically used as an essential part of such a backlight unit. However, the thickness of the light guide plate itself can not be reduced due to the thickness of the light guide plate itself, .

SUMMARY OF THE INVENTION The present invention has been conceived to solve the problems described above, and it is an object of the present invention to provide a capsule unit which realizes thinning of a backlight unit using a resin layer as a light guide plate, And to provide a backlight unit capable of improving the heat radiation characteristic by using an air layer or a vacuum state of the spacing space while protecting the LED.

According to an aspect of the present invention, there is provided an LED light source comprising: a plurality of LED light sources formed on a printed circuit board; A resin layer stacked on the printed circuit board and diffusing light emitted from the LED light source forward; And a capsule portion that seals a peripheral portion of the LED to form a space separated from the resin layer.

Particularly, the backlight unit can be realized by a structure in which a reflection pattern is implemented on the inner surface of the capsule unit, or a reflection layer in which a reflection pattern is implemented on the resin layer.

In this case, the inside of the capsule portion may be formed as an air layer or a vacuum may be formed, and the capsule portion may be realized as a dome-shape in which a lower surface is opened and a space portion is formed therein.

The backlight unit according to the present invention may further comprise a reflective film on which a reflective pattern is formed on the printed circuit board.

In this case, the reflection pattern formed on the reflective film can be formed by applying a reflective ink containing any one of TiO ₂ , CaCO ₃ , BaSO ₄ , Al ₂ O ₃ , Silicon, and PS (Poly Stylen).

In addition, the resin layer may further include a bead for increasing the reflection of light to 0.01 to 0.3% of the entire resin layer.

In addition, the resin layer may further include an optical pattern layer on which an optical pattern is printed. In this case, the optical pattern layer may be formed by printing an optical pattern on a lower portion of the diffusion plate.

In particular, the optical pattern may be a light-shielding pattern formed of a material including at least one material selected from TiO ₂ , CaCO ₃ , BaSO ₄ , Al ₂ O ₃ , Silicon, and PS (Poly Stylen).

A backlight unit according to the present invention having the above-described structure is characterized in that an LED is mounted on a printed circuit board, a capsule portion having an accommodation space for sealing the periphery of the LED is mounted, and then a resin layer is applied to the printed circuit board ≪ / RTI > process.

The thus fabricated backlight unit according to the present invention can be applied to a liquid crystal display device to perform a function of supplying light.

According to the present invention, there is provided a light emitting device, comprising: a resin layer; a light guide plate; a backlight unit; and a capsule portion sealing the peripheral portion of the LED to form a space with the resin layer. So that the heat dissipation characteristics can be improved.

In particular, it has various reflection patterns for amplifying diffused light scattering of light, thereby greatly reducing the number of light sources and securing optical characteristics. Also, it is applicable to a structure of a flexible display by removing a light guide plate. And a diffusing plate including a light-shielding pattern are further provided, so that stable light emission characteristics can be ensured.

1A and 1B are conceptual diagrams showing the structure of a backlight unit according to the related art.
2 is a conceptual view showing the structure of a backlight unit according to the present invention.
FIG. 3 or FIG. 4 shows another embodiment of the backlight unit according to the present invention.
5 is a process diagram schematically showing a manufacturing process of a backlight unit according to the present invention.

Hereinafter, the configuration and operation according to the present invention will be described in detail with reference to the accompanying drawings. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the following description with reference to the accompanying drawings, the same reference numerals denote the same elements regardless of the reference numerals, and redundant description thereof will be omitted. The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another.

The present invention provides a backlight unit having a resin layer for removing a light guide plate in a structure of a conventional backlight unit and having a capsule portion for forming a space between the resin layer and the LED, And the like.

Referring to FIG. 2, FIG. 2 is a conceptual diagram illustrating a configuration of a backlight unit according to the present invention.

Referring to the drawings, a backlight unit according to the present invention includes a plurality of LED light sources 130 formed on a printed circuit board 110, a plurality of LED light sources 130 stacked on the printed circuit board 110, And a capsule portion (C) for sealing the peripheral portion of the LED and forming a space (P) separated from the resin layer. Of course, in the above-described structure, the reflective film 120 may be provided on the upper surface of the printed circuit board, and a plurality of reflective patterns 121 may be provided on the reflective film 120 .

Particularly, the capsule portion has various shapes (a 'capsule' portion in the present invention) that forms a spacing space such that the side surface and the upper surface of the LED mounted on the printed circuit board 110 are not in contact with the resin layer, Is defined as a transparent material.

Specifically, the capsule portion C prevents a direct contact between the LED light source 130 and the resin layer 140, and functions to prevent damage to the LED due to resin do. 2, the capsule portion C has a space P in a sealed structure between the LED 130 and the resin layer 140, It is possible to realize the effect of reducing the heat transfer from the LED to the resin layer by being maintained in the air layer or the vacuum state. The capsule portion C has a dome-shaped structure, an open bottom portion and a dome-shaped top portion to seal the LED and the spacing space. However, The shape is not limited thereto and can be modified into various structures for changing the incident angle while inducing the refractive index of light.

In addition, since the peripheral portion of the LED 130 is sealed with the encapsulation portion C, the resin layer 140 applied on the encapsulation portion C is stably attached to the printed circuit board 110 without forming a separate structure . A reflective pattern 150 may be formed on the inner surface of the capsule portion C. In the illustrated structure, in order to emit light concentrated at the center portion by the top view type LED light source, The reflection pattern 150 may be further formed inside the capsule portion as needed.

The LED light sources 130 are arranged in at least one or more numbers on the printed circuit board 110 and emit light. In a preferred embodiment of the present invention, a side view LED or a top view LED view LED) can be used. The above-described LED light source is disposed directly underneath, and the total thickness of the backlight unit can be innovatively reduced while reducing the total number of light sources by utilizing the resin layer that implements the light diffusion and reflection function.

The resin layer 140 is stacked in a structure surrounding the LED light source 111 and functions to disperse light of a light source emitting in a lateral direction. That is, the function of the conventional light guide plate can be performed in the resin layer 140. It is needless to say that the resin layer can be basically made of any resin capable of diffusing light. For example, the main material of the resin layer according to one embodiment of the present invention may be a resin having urethane acrylate oligomer as a main material. For example, a mixture of urethane acrylate oligomer, which is a synthetic oligomer, with a polymer type of polyacrylic can be used. Of course, it may further comprise a monomer mixed with a low-boiling-point diluent type reactive monomer such as isobornyl acrylate (IBOA), hydroxypropyl acrylate (HPA), or 2-hydroxyethyl acrylate (HPA). A photoinitiator -hydroxycyclohexyl phenyl-ketone) or an antioxidant.

The resin layer 140 may include a bead to increase diffusion and reflection of light. Preferably, the bead comprises 0.01 to 0.3% by weight of the total resin layer. That is, the light emitted from the LED can be diffused and reflected through the resin layer 140 and the bead, and can proceed to the upper direction. When the reflective film 120 and the reflective pattern 121 are provided, So that it can be further promoted. The presence of the resin layer can reduce the thickness of the conventional light guide plate to thereby reduce the thickness of the entire product. In addition, it is possible to provide a versatility applicable to a flexible display having a flexible material do.

The reflective film 120 may have a reflective material to disperse light emitted from the light source, and may further include a reflective pattern 121 through white printing to promote dispersion of light. The reflective pattern may be printed using reflective ink including any one of TiO ₂ , CaCO ₃ , BaSO ₄ , Al ₂ O ₃ , Silicon, and PS (Poly Stylen).

3 illustrates another embodiment of the backlight unit according to the present invention. Unlike the structure described above with reference to FIG. 2, the backlight unit according to the present invention is not a structure for forming a reflection pattern on the inner side of the capsule unit C, And a reflection pattern 150 is formed on the reflective layer 150. The reflection pattern 150 may be printed on a lower portion of the substrate 160, and the substrate 160 may be a diffusion plate. Of course, it is also possible to form a structure in which a separate reflection pattern 150 is implemented in this embodiment, and a reflection pattern implemented on the inner side of the capsule portion in FIG. 2 is further added.

4 shows another embodiment of the backlight unit according to the present invention. The basic structure of the backlight unit is the same as that of FIG. 2, but it is exemplified that the shape of the capsule portion C can be modified differently.

That is, the capsule portion C according to the present invention may be embodied in various shapes of members that form a space so that the side surface and the upper surface of the LED 130 mounted on the printed circuit board 110 are not in contact with the resin layer , In particular, the deformation of such a shape may be realized in a double-dome structure having two or more bends as shown in addition to the dome structure. Of course, other than a dome structure, various polygonal prisms or polygonal pyramids can be implemented.

It is also possible to implement the reflection pattern 150 as described above on the inner surface of the capsule portion of the double-dome structure shown in the drawing, or to implement a reflection pattern on the upper portion of the resin layer 140 separately. In addition, the reflective film 120 having the reflective pattern 121 may be laminated on the surface of the printed circuit board 110 as described above in the embodiment of FIG.

In addition, an optical pattern layer disposed on the upper surface of the resin layer 140 may be implemented in the structure of the backlight unit according to the present invention described with reference to FIGS. The optical pattern layer means a substrate on which a pattern for performing a function of shielding or diffusing is printed on the lower surface. Particularly, a substrate having excellent light transmittance can be used. For example, PET can be used. In this case, the substrate may be a diffusion plate.

For example, in implementing such an optical pattern, a light shielding ink containing at least one material selected from the group consisting of TiO ₂ , CaCO ₃ , BaSO ₄ , Al ₂ O ₃ , and Silicon is used for the lower surface of the polymer film in the light emitting direction A light-shielding pattern using a light-shielding ink containing a diffusion pattern to be formed and a mixed material of Al or Al and TiO ₂ . Further, a pattern material made of a ceramic material containing air may be mixed in the optical pattern. This makes it possible to realize the refractive index of the air inside by using the ceramic material including the air structure, so that the brightness and the light uniformity can be improved.

The optical pattern of the superimposed printing structure can be formed by forming a diffusion pattern by white printing and then forming a light shielding pattern thereon or by forming a double structure in the reverse order. Of course, it will be obvious that the formation design of such a pattern can be variously modified in consideration of light efficiency, intensity, and shading ratio. Alternatively, it is also possible to form a light-shielding pattern, which is a metal pattern, in the middle layer in a sequential layer structure, and a triple-layer structure in which diffusion patterns are formed on the upper and lower portions, respectively. In such a triple structure, the above-mentioned materials can be selected and implemented. As a preferable example, one of the diffusion patterns is realized by using TiO ₂ having excellent refractive index, and CaCO ₃ having excellent light stability and color is used together with TiO ₂ The light diffusing pattern can be realized and the light efficiency and homogeneity can be ensured through the triple structure which realizes a light shielding pattern by using Al which is excellent in concealment. Particularly, CaCO ₃ functions to reduce the exposure of yellow light and finally realize white light. Thus, it is possible to realize light with more stable efficiency. In addition to CaCO ₃ , particles such as BaSO ₄ , Al ₂ O ₃ , It is also possible to utilize inorganic materials having a large size and a similar structure. In addition, it is preferable that the optical pattern is formed by adjusting the pattern density so that the pattern density becomes lower as the distance from the emitting direction of the LED light source decreases.

5 illustrates a manufacturing process for manufacturing a backlight unit according to the present invention.

Referring to the illustrated process flow, the structure shown in S 1 illustrates one embodiment of a process for manufacturing a capsule portion according to the present invention. That is, the molds P1 and P2 having the shape of the capsule portion are prepared, and the capsule portion C is formed by the injection or die method.

Step S21 is a process of embodying the reflection pattern 150 on the inner surface of the capsule portion C, and in this embodiment, it is possible to implement the reflection pattern by printing the reflection pattern.

Thereafter, in step S22, the reflective film 120 is mounted on the printed circuit board 110, and the encapsulated part C, in which the reflective pattern 150 is implemented in step S21, The resin layer 140 is formed by applying resin to the upper surface of the capsule portion C and the printed circuit board and curing the resin. The application of the resin layer 140 is advantageous in that the adhesiveness between the capsule portion C and the printed circuit board can be stably ensured without a separate structure.

After this process, as described above, an optical sheet such as a prism sheet or a DBEF is added to form an optical pattern layer or a later added white light. The backlight unit thus manufactured is applied to a liquid crystal display device, .

As described above, the backlight unit according to the present invention can realize the thinning of the backlight unit by using the resin layer as the light guide plate, and the special capsule portion can be arranged to seal the peripheral portion of the LED to protect the LED, , In particular, stable light emission characteristics can be ensured.

In the foregoing detailed description of the present invention, specific examples have been described. However, various modifications are possible within the scope of the present invention. The technical idea of the present invention should not be limited to the embodiments of the present invention but should be determined by the equivalents of the claims and the claims.

110: printed circuit board
120: reflective film
121: reflection pattern
130: Light source
140: Resin layer
150: reflection pattern
160: substrate
C: Capsule part
P: Spacing space

Claims (13)

Printed circuit board;
A plurality of LED light sources disposed on the printed circuit board;
A resin layer stacked on the printed circuit board and diffusing light emitted from the LED light source forward;
A capsule portion having a dome structure for sealing a peripheral portion of the LED to form a space separated from the resin layer; And
And a first reflection pattern disposed between the resin layer and the spacing space and disposed inside the capsule section,
Wherein the first reflective pattern has a curvature and is vertically overlapped with a portion of the LED light source,
And a reflective film laminated on the upper surface of the printed circuit board,
A second reflective pattern on the reflective film,
Wherein the second reflective pattern is spaced apart from the LED light source and does not overlap vertically with the first reflective pattern. delete The method according to claim 1,
And a reflective layer including a third reflective pattern on the resin layer,
And the third reflective pattern is vertically overlapped with the LED light source.
The method according to claim 1 or 3,
Wherein an air layer is formed inside the capsule portion or a vacuum is formed.
The method of claim 4,
The capsule portion
A lower surface is opened and a space portion is formed therein,
Wherein the first reflection pattern is disposed above the space portion.
delete The method according to claim 1,
Wherein the second reflective pattern is formed by:
A backlight unit formed by applying a reflective ink containing any one of TiO ₂ , CaCO ₃ , BaSO ₄ , Al ₂ O ₃ , Silicon, and PS (Poly Stylen).
The method of claim 4,
Wherein the resin layer further comprises a bead for increasing light reflection to 0.01 to 0.3% of the entire resin layer.
The method according to claim 1,
On top of the resin layer,
A backlight unit further comprising an optical pattern layer on which an optical pattern is printed.
The method of claim 9,
Wherein the optical pattern layer comprises:
And the optical pattern is printed on the lower part of the diffusion plate.
The method of claim 9,
Wherein the optical pattern layer comprises:
Wherein the backlight unit is a light-shielding pattern formed of a material including at least one material selected from TiO ₂ , CaCO ₃ , BaSO ₄ , Al ₂ O ₃ , Silicon, and PS (Poly Stylen).
Printed circuit board;
A plurality of LED light sources disposed on the printed circuit board;
A resin layer stacked on the printed circuit board and diffusing light emitted from the LED light source forward;
A capsule portion that seals a peripheral portion of the LED to form a space separated from the resin layer; And
And a first reflection pattern disposed between the resin layer and the spacing space and disposed inside the capsule section,
Wherein the capsule portion has a double-dome structure having two or more bends,
Wherein the boundary region of the double-dome structure is vertically overlapped with a central portion of the LED light source.
The method of claim 12,
Wherein the first reflection pattern is disposed on the at least two curved surfaces, and the first reflection pattern is vertically overlapped with an edge of the LED light source.

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