KR20150059390A - Backlight unit and lighting device - Google Patents

Abstract

The present invention relates to a back light unit which can be used for a display or lighting, and to a lighting device. The back light unit comprises: a light guide plate of a transparent material, where at least one penetration hole is formed; a light emitting diode installed on the penetration hole of the light guide plate; and a reverse horn-shaped reflector inserted and installed in the penetration hole of the light guide plate to induce light generated from the light emitting diode to the light guide plate direction, where the top is flat, and the bottom is formed in a sharp corn shape.

Description

BACKLIGHT UNIT AND LIGHT DEVICE [0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a backlight unit and a lighting apparatus, and more particularly, to a backlight unit and a lighting apparatus which can be used for a display or an illumination.

A light emitting diode (LED) is a kind of semiconductor device that can emit light of various colors by forming a light emitting source through the formation of a PN diode of a compound semiconductor. Such a light emitting device has a long lifetime, can be reduced in size and weight, and can be driven at a low voltage. In addition, these LEDs are resistant to shock and vibration, do not require preheating time and complicated driving, can be packaged after being mounted on a substrate or lead frame in various forms, so that they can be modularized for various purposes and used as a backlight unit A lighting device, and the like.

The direct-type light emitting device package widely used in the backlight unit can widely disperse light generated from the light emitting device package through the secondary lens so as to reduce the thickness of the unit and uniformly irradiate the light to the light guide plate.

However, in the conventional light emitting device package, the overall thickness of the product is increased due to the secondary lens, and the lens is distorted to cause luminance and color deviation. Such luminance and chromatic aberration deteriorates optical characteristics, ) Phenomenon or the uniformity of light irradiated on the light guide plate or the display panel is markedly lowered, resulting in defective products.

Disclosure of Invention Technical Problem [8] The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide an image display device which does not require a separate secondary lens, can reduce the thickness of a product, And to provide a backlight unit and a lighting apparatus which can improve a light characteristic and produce a high quality product. However, these problems are exemplary and do not limit the scope of the present invention.

According to an aspect of the present invention, there is provided a backlight unit comprising: a light guide plate having at least one through hole and being made of a transparent material; A light emitting element provided in a through hole of the light guide plate; And an inverted horn-shaped reflector inserted into the through hole of the light guide plate so as to guide the light generated from the light emitting element toward the light guide plate, the upper portion being flat and the lower portion being formed into a sharp cone shape can do.

The backlight unit according to an aspect of the present invention may further include a fixing member provided between the light guide plate and the inverted horn type reflector and fixing the inverted horn type reflector to the through hole of the light guide plate.

According to an aspect of the present invention, the inverse horn-type reflector is filled in the inside, and the fixing member is provided on an edge of an upper surface of the inverted horn-shaped reflector and has a flange portion contacting the peripheral portion of the through- .

According to an aspect of the present invention, the light guide plate may have a flange groove portion having a shape corresponding to the flange portion at a peripheral portion of the through hole so that the flange portion can be seated.

According to an aspect of the present invention, the inverse horn-shaped reflector is an inverted conical shape, and the flange portion may be a disk-shaped ring-shaped metal made of an opening formed at the center.

According to an aspect of the present invention, the fixing member may be at least three or more vertical leg portions provided on the inverse horn-shaped reflector and along the inner diameter surface of the through hole.

According to an aspect of the present invention, the vertical legs are plate-shaped blades that are arranged on the radiation with the light emitting element as a center, the edge portions are directed toward the light emitting device, And may be in contact with the inner diameter surface of the through hole of the light guide plate.

According to an aspect of the present invention, the inverted horn-shaped reflector may be an opaque material having a reflective surface formed on an outer surface thereof, or a translucent material having a reflective surface formed on an outer surface thereof.

The backlight unit according to the present invention may further include an optical system provided on a flat upper surface of the inverted horn-shaped reflector, wherein the optical system includes a partial reflection layer having at least a constant thickness, a total reflection layer, A sheet layer, a scattering layer, a refraction layer, a metal layer, a Bragg reflection layer, an air gap, and a combination thereof.

According to an aspect of the present invention, there is provided a lighting apparatus comprising: a light guide plate having at least one through hole and being made of a light transmitting material; A light emitting element provided in a through hole of the light guide plate; And an inverted horn-shaped reflector inserted into the through hole of the light guide plate so as to guide the light generated from the light emitting element toward the light guide plate, the upper portion being flat and the lower portion being formed into a sharp cone shape can do.

According to some embodiments of the present invention as described above, the thickness of the product is reduced, and the optical characteristics of the product are improved, thereby producing a high-quality and high-quality product. Of course, the scope of the present invention is not limited by these effects.

1 is an exploded perspective view of a part of a backlight unit according to some embodiments of the present invention.
2 is a cross-sectional view showing the backlight unit of Fig.
3 is an enlarged cross-sectional view showing an enlarged view of the backlight unit of Fig.
4 is an enlarged cross-sectional view showing a backlight unit according to some other embodiments of the present invention.
5 is an enlarged cross-sectional view illustrating a backlight unit according to still another embodiment of the present invention.
6 is a perspective view illustrating a backlight unit according to still another embodiment of the present invention.
7 is an enlarged sectional view showing the backlight unit of Fig.
8 is an enlarged cross-sectional view illustrating a backlight unit according to still another embodiment of the present invention.
9 is a perspective view showing a backlight unit according to still another embodiment of the present invention.
10 is a plan view showing the backlight unit of Fig.
11 is an enlarged cross-sectional view illustrating a backlight unit according to still another embodiment of the present invention.

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

The embodiments of the present invention are described in order to more fully explain the present invention to those skilled in the art, and the following embodiments may be modified into various other forms, The present invention is not limited to the embodiment. Rather, these embodiments are provided so that this disclosure will be more thorough and complete, and will fully convey the concept of the invention to those skilled in the art. In the drawings, the thickness and size of each layer are exaggerated for convenience and clarity of explanation.

It is to be understood that throughout the specification, when an element such as a film, region or substrate is referred to as being "on", "connected to", "laminated" or "coupled to" another element, It will be appreciated that elements may be directly "on", "connected", "laminated" or "coupled" to another element, or there may be other elements intervening therebetween. On the other hand, when one element is referred to as being "directly on", "directly connected", or "directly coupled" to another element, it is interpreted that there are no other components intervening therebetween do. Like numbers refer to like elements. As used herein, the term "and / or" includes any and all combinations of one or more of the listed items.

Although the terms first, second, etc. are used herein to describe various elements, components, regions, layers and / or portions, these members, components, regions, layers and / It is obvious that no. These terms are only used to distinguish one member, component, region, layer or section from another region, layer or section. Thus, a first member, component, region, layer or section described below may refer to a second member, component, region, layer or section without departing from the teachings of the present invention.

Also, relative terms such as "top" or "above" and "under" or "below" can be used herein to describe the relationship of certain elements to other elements as illustrated in the Figures. Relative terms are intended to include different orientations of the device in addition to those depicted in the Figures. For example, if the element is inverted in the figures, the elements depicted as being on the upper surface of the other elements will have a direction on the lower surface of the other elements. Thus, the example "top" may include both "under" and "top" directions depending on the particular orientation of the figure. If the elements are oriented in different directions (rotated 90 degrees with respect to the other direction), the relative descriptions used herein can be interpreted accordingly.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms "a," "an," and "the" include singular forms unless the context clearly dictates otherwise. Also, " comprise "and / or" comprising "when used herein should be interpreted as specifying the presence of stated shapes, numbers, steps, operations, elements, elements, and / And does not preclude the presence or addition of one or more other features, integers, operations, elements, elements, and / or groups.

Hereinafter, embodiments of the present invention will be described with reference to the drawings schematically showing ideal embodiments of the present invention. In the figures, for example, variations in the shape shown may be expected, depending on manufacturing techniques and / or tolerances. Accordingly, the embodiments of the present invention should not be construed as limited to the particular shapes of the regions shown herein, but should include, for example, changes in shape resulting from manufacturing.

1 is a part exploded perspective view showing a backlight unit 100 according to some embodiments of the present invention. FIG. 2 is a cross-sectional view showing the backlight unit 100 of FIG. 1, and FIG. 3 is an enlarged cross-sectional view showing the backlight unit 100 of FIG. 1 in an enlarged scale.

1, a backlight unit 100 according to some embodiments of the present invention may include a light guide plate 10, a light emitting device 20, and an inverted horn reflector 30 .

The light guide plate 10 may have at least one through hole H formed on the upper surface or the lower surface thereof at regular intervals and may be made of a light transmitting material so as to guide light generated from the light emitting device 20 Or the like.

The light guide plate 10 may be installed in a path of light generated by the light emitting device 20 to transmit light generated by the light emitting device 20 over a wider area.

The light guide plate 10 may be made of polycarbonate, polysulfone, polyacrylate, polystyrene, polyvinyl chloride, polyvinyl alcohol, polynorbornene, polyester, or the like , And various light transmitting resin materials may be applied. The light guide plate 10 may be formed by various methods such as forming fine patterns, fine protrusions, diffusion films, or the like on the surface or forming fine bubbles therein.

Although not shown, various diffusion sheets, prism sheets, filters, and the like may be additionally provided above the light guide plate 10.

As shown in FIG. 2, various display panels P such as an LCD panel may be installed above the light guide plate 10.

The backlight unit 100 according to some embodiments of the present invention may be a direct-type backlight unit in which the light emitting device 20 is installed below the light guide plate 10 as shown in FIG. 1 . In addition, the backlight unit may be an edge-type backlight unit in which the light emitting device 20 is installed on the side of the light guide plate 10 as a whole.

The light emitting device 20 is a kind of light source that is mounted on the substrate S and is electrically connected to a power source or a control unit and installed in the through hole H of the light guide plate 10

The substrate S may be made of a material or a conductive material having appropriate mechanical strength and insulation so as to support the light emitting devices 20, at least one side of which is opposed to the light guide plate 10 have.

For example, the substrate S may be a printed circuit board (PCB) having a plurality of epoxy resin sheets formed thereon. The substrate S may be a flexible printed circuit board (FPCB) made of a flexible material.

The substrate S may be a synthetic resin substrate such as a resin or a glass epoxy or a ceramic substrate in consideration of thermal conductivity and may be formed of an insulating material such as aluminum, copper, zinc, tin, A metal substrate such as silver can be applied, and a plate or a lead frame substrate can be applied.

The substrate S may be made of at least one selected from EMC (Epoxy Mold Compound), PI (polyimide), ceramic, graphene, glass synthetic fiber and combinations thereof to improve workability have.

Meanwhile, the light emitting device 20 may be formed of a semiconductor, as shown in FIGS. For example, LEDs of blue, green, red, and yellow light emission, and LEDs of ultraviolet light emission, which are made of a nitride semiconductor, can be applied. The nitride semiconductor is represented by a general formula Al _x Ga _y In _z N (0? X? 1, 0? Y? 1, 0? Z? 1, x + y + z = 1).

The light emitting device 20 can be formed by epitaxially growing nitride semiconductors such as InN, AlN, InGaN, AlGaN, and InGaAlN on a sapphire substrate for growth or a silicon carbide substrate by a vapor phase growth method such as MOCVD To grow. The light emitting device 20 may be formed using semiconductors such as ZnO, ZnS, ZnSe, SiC, GaP, GaAlAs, and AlInGaP in addition to the nitride semiconductor. These semiconductors can be stacked in the order of an n-type semiconductor layer, a light emitting layer, and a p-type semiconductor layer. The light emitting layer (active layer) may be a laminated semiconductor having a multiple quantum well structure or a single quantum well structure or a laminated semiconductor having a double hetero structure. In addition, the light emitting device 20 can be selected to have an arbitrary wavelength depending on the application such as display use and illumination use.

Here, as the growth substrate, an insulating, conductive or semiconductor substrate may be used if necessary. For example, the growth substrate may be sapphire, SiC, Si, MgAl 2 O 4, MgO, LiAlO 2, LiGaO 2, GaN. A GaN substrate, which is a homogeneous substrate, is preferable for epitaxial growth of a GaN material, but a GaN substrate has a problem of high production cost due to its difficulty in manufacturing.

Sapphire and silicon carbide (SiC) substrates are mainly used as the different substrates. Sapphire substrates are more utilized than expensive silicon carbide substrates. When using a heterogeneous substrate, defects such as dislocation are increased due to the difference in lattice constant between the substrate material and the thin film material. Also, due to the difference in the thermal expansion coefficient between the substrate material and the thin film material, warping occurs at a temperature change, and warping causes a crack in the thin film. This problem may be reduced by using a buffer layer between the substrate and the GaN-based light emitting laminate.

In addition, the substrate for growth may be completely or partially removed or patterned in order to improve the optical or electrical characteristics of the LED chip before or after the growth of the LED structure.

For example, in the case of a sapphire substrate, the substrate can be separated by irradiating the laser to the interface with the semiconductor layer through the substrate, and the silicon or silicon carbide substrate can be removed by a method such as polishing / etching.

Another supporting substrate may be used for removing the growth substrate. In order to improve the light efficiency of the LED chip on the opposite side of the growth substrate, the supporting substrate may be bonded using a reflective metal, As shown in FIG.

In addition, patterning of the growth substrate improves the light extraction efficiency by forming irregularities or slopes before or after the LED structure growth on the main surface (front surface or both sides) or side surfaces of the substrate. The size of the pattern can be selected from the range of 5 nm to 500 μm and it is possible to make a structure for improving the light extraction efficiency with a rule or an irregular pattern. Various shapes such as a shape, a column, a mountain, a hemisphere, and a polygon can be adopted.

In the case of the sapphire substrate, the crystals having a hexagonal-rhombo-cubic (Hexa-Rhombo R3c) symmetry have lattice constants of 13.001 and 4.758 in the c-axis direction and the a-axis direction, respectively, and have C plane, A plane and R plane. In this case, the C-plane is relatively easy to grow the nitride film, and is stable at high temperature, and thus is mainly used as a substrate for nitride growth.

Another material of the growth substrate is a Si substrate, which is more suitable for large-scale curing and relatively low in cost, so that mass productivity can be improved.

In addition, since the silicon (Si) substrate absorbs light generated from the GaN-based semiconductor and the external quantum efficiency of the light emitting device is lowered, the substrate may be removed as necessary, and Si, Ge, SiAl, A support substrate such as a metal substrate is further formed and used.

When a GaN thin film is grown on a different substrate such as the Si substrate, the dislocation density increases due to the lattice constant mismatch between the substrate material and the thin film material, and cracks and warpage Lt; / RTI > The buffer layer may be disposed between the growth substrate and the light emitting stack for the purpose of preventing dislocation and cracking of the light emitting stack. The buffer layer also functions to reduce the scattering of the wavelength of the wafer by adjusting the degree of warping of the substrate during the growth of the active layer.

Here, the buffer layer may be made of Al _x In _y Ga _1-xy N (0? X? 1, 0? _Y? 1, x + y? 1), in particular GaN, AlN, AlGaN, InGaN or InGaNAlN. Materials such as ZrB2, HfB2, ZrN, HfN and TiN can also be used as needed. Further, a plurality of layers may be combined, or the composition may be gradually changed.

Although not shown, the light emitting device 20 may be a flip chip type light emitting device having a signal transmission medium such as a bump, a pad, or a solder, or a horizontal type or vertical type light emitting device.

1 to 3, the inverse horn-type reflector 30 is disposed on the light guide plate 10 so as to guide the light generated from the light emitting device 20 toward the light guide plate 10, May be inserted into the through hole (H), and the reflector may be formed in a cone shape with a flat upper part and a sharp cone.

1 to 3, the inverse horn-type reflector 30 is integrally formed with the light emitting device 20 so as to guide light emitted from the light emitting device 20 in a lateral direction, that is, As shown in FIG.

2, when the width of the inverted horn-shaped reflector 30 is limited, the angle of the reflection surface 30a may be changed according to the height H1. That is, the designer can adjust the angle of light reflected toward the light guide plate 10 by adjusting the height H1 of the inverted horn-shaped reflector 30.

For example, when the height H1 of the inverted horn-shaped reflector 30 is high, the angle of light reflected toward the light guide plate 10 can be increased, and the height H1 of the inverted horn- The angle of the light reflected toward the light guide plate 10 may be lowered.

Accordingly, the height H1 of the inverted horn-shaped reflector 30 may be appropriately designed to guide more light toward the light guide plate 10 in an optimal state.

In addition, the inverted horn-shaped reflector 30 may be formed in a triangular, quadrangular, polygonal, conical, or various geometrical conical shape as well as a conical shape.

The inverted horn-shaped reflector 30 may have a generally horn-shaped upper portion and a narrow downward portion or a pointed portion. The pointed portion may be provided toward the light-emitting element 20.

3, the inverse horn-type reflector 30 may be formed of at least silver, platinum, gold, mercury, chrome, or the like having high reflectance so as to reflect light emitted from the light emitting device 20 in the lateral direction. And a combination of any of these.

In addition, the inverse horn reflector 30 may be at least one of EMC, an epoxy resin composition, a silicone resin composition, a modified epoxy resin composition, a modified silicone resin composition, a polyimide resin composition, a modified polyimide resin composition, a polyphthalamide (PPA) (PPS), a liquid crystal polymer (LCP), an ABS resin, a phenol resin, an acrylic resin, a PBT resin, a Bragg reflection layer, an air gap, a total reflection layer, Or a combination thereof.

The inverse horn-type reflector 30 may be made of at least one of EMC, EMC including at least a reflective material, white silicon containing a reflective material, a photoimageable solder resist (PSR), and combinations thereof.

More specifically, for example, the inverted-horn reflector 30 may be formed of a modified silicone resin composition such as an epoxy resin composition, a silicone resin composition, a modified epoxy resin composition such as a silicone modified epoxy resin, an epoxy modified silicone resin, A resin such as polyimide resin composition, modified polyimide resin composition, polyphthalamide (PPA), polycarbonate resin, polyphenylene sulfide (PPS), liquid crystal polymer (LCP), ABS resin, phenol resin, acrylic resin, PBT resin Etc. may be applied.

Further, a light reflecting material such as titanium oxide, silicon dioxide, titanium dioxide, zirconium dioxide, potassium titanate, alumina, aluminum nitride, boron nitride, mullite, chromium, have.

3, the operation of the backlight unit 100 according to some embodiments of the present invention will be described. First, the light generated from the light emitting device 20 is reflected by the inverse horn-shaped reflector 30 The light is reflected by the reflection surface 30a of the inverted horn-shaped reflector 30 and can be guided in the direction of 360 degrees in the direction of the light guide plate 10.

Therefore, instead of the conventional biasing of light generated in the light emitting device 20 and concentrated vertically upward, light generated in the light emitting device 20 is guided in the lateral direction, Mura phenomenon, luminance deviation and color deviation, thereby improving optical characteristics and producing high quality products.

That is, all of the light in the upper right room of the light emitting element 20 capable of forming a name portion is cut off and guided to the side where the arm portion can be formed, thereby guiding light to the display panel P as a whole with a uniform light intensity .

In other words, the inverted horn-shaped reflector 30 may be fabricated such that the inside thereof is filled with an opaque material such as a metal having a reflective surface 30a formed on the outer surface thereof.

4 is an enlarged cross-sectional view illustrating a backlight unit according to some other embodiments of the present invention.

In addition, as shown in FIG. 4, the backlight unit according to some other embodiments of the present invention may be made of a transmissive material in which the reflective surface 30a is formed on the outer surface .

Here, the light-transmissive material may be a material capable of partially reflecting a part of light and allowing another part of light to pass therethrough.

Such a translucent material may be selected from the group consisting of glass, acrylic, and epoxy resin as well as EMC, epoxy resin composition, silicone resin composition, modified epoxy resin composition, modified silicone resin composition, polyimide resin composition, modified polyimide resin composition, polyphthalamide PPA), polycarbonate resin, polyphenylene sulfide (PPS), liquid crystal polymer (LCP), ABS resin, phenol resin, acrylic resin, PBT resin and the like.

In addition, the inverse horn-type reflector 30 may be formed by a separate molding process, not by cutting or etching.

The inverse horn-type reflector 30 may be molded into a strip so that the inverse horn-type reflectors 30 are connected to each other and simultaneous processing can proceed collectively.

4, the operation of the inverse horn-type reflector 30, which is a translucent material of the backlight unit according to some embodiments of the present invention, will be described. First, When the light is irradiated in the direction of the inverted horn-shaped reflector 30, a part of the light is reflected by the reflection surface 30a of the inverted horn-shaped reflector 30 and is emitted toward the light guide plate 10 in the 360- And another portion of the light may be emitted to the upper chamber of the light emitting device 20 through the filled interior of the inverted horn-shaped reflector 30. [

Therefore, by precisely adjusting the reflectivity and the transmittance of the inverted-horn reflector 30, it is possible to provide a light emitting device 20 The light generated in the light guide plate 10 is appropriately guided in the lateral direction to prevent a mura phenomenon, a luminance deviation and a color deviation which are generated in the light guide plate 10, thereby improving optical characteristics and producing a good quality product.

That is, the light in the upper right room of the light emitting device 20, which can form the light or dark portion, can be partially blocked or opened to guide the light to the display panel P with a uniform light intensity as a whole.

1 to 4, a backlight unit 100 according to some embodiments of the present invention is installed between the light guide plate 10 and the inverted horn-shaped reflector 30, And a fixing member 40 for fixing the reflector 30 to the through hole H of the light guide plate 10.

The fixing member 40 may be a flange portion 41 provided at an upper surface of the inverted horn-shaped reflector 30 and contacting the peripheral portion of the through hole H of the light guide plate 10.

2 to 4, the fixing member 40 is formed to have a size larger than the size of the inverted horn-shaped reflector 30 so that the inverted horn-shaped reflector 30 penetrates the through hole H, Through the hole H so as to prevent it from falling into the through hole H.

2 to 4, the inverted horn-shaped reflector 30 does not collide with the light emitting element 20 by the flange portion 41, but does not collide with the light emitting element 20 at the position Can be fixed.

An adhesive layer may be formed between the flange portion 41 and the peripheries of the through holes H to firmly adhere the flange portions 41 to the light guide plate 10.

In addition, the flange portion 41 may be fixed to the light guide plate 10 by various fixtures.

5 is an enlarged cross-sectional view illustrating a backlight unit according to still another embodiment of the present invention.

5, the light guide plate 10 of the backlight unit according to still another embodiment of the present invention is provided with the flange portion 41 on the periphery of the through hole H, A flange groove portion 11 having a shape corresponding to the supporting portion 41 can be formed.

5, the inverted horn-shaped reflector 30 is formed such that the flange portion 41 is inserted into the flange groove portion 11 and does not protrude upward from the light guide plate 10, .

An adhesive layer may be formed between the flange portion 41 and the flange groove portion 11 to firmly adhere the flange portion 41 to the light guide plate 10.

In addition, the flange portion 41 may be fixed to the light guide plate 10 by various fixtures.

FIG. 6 is a perspective view showing a backlight unit according to still another embodiment of the present invention, and FIG. 7 is an enlarged sectional view showing the backlight unit of FIG.

6 and 7, the flange portion 42 of the backlight unit according to some further embodiments of the present invention may be a disk-shaped ring-shaped metal material having an opening 42a formed at the center thereof .

Here, the flange portion 42 made of a metal is excellent in wear resistance, so that durability and rigidity of the component can be improved.

The flange portion 42 may be formed by molding a plurality of the inverse-horn-shaped reflectors 30 in a strip so that simultaneous processing can proceed simultaneously, It is possible to improve the binding force between the two.

In addition, the size of the opening 42a is optimally designed so that a part of the light passing through the inside of the inverted-horn-shaped reflector 30 of the light-transmitting material is emitted upward to precisely control the formation of the name portion or the dark portion .

8 is an enlarged cross-sectional view illustrating a backlight unit according to still another embodiment of the present invention.

8, the flange portion 43 of the backlight unit according to still another embodiment of the present invention is formed with a male screw portion, the flange groove portion 12 is formed with a female screw portion corresponding to the male screw portion, A driver groove (D) may be formed on the upper surface of the inverted horn-shaped reflector (30).

Therefore, while the inverse horn-type reflector 30 is assembled to the light guide plate 10, the operator uses the driver groove D to project the inverted horn-shaped reflector 30 onto the light guide plate 10 Through holes (H) of the main body (1).

In this case, the operator can adjust the height of the inverted horn-shaped reflector 30 by adjusting the number of revolutions of the driver. For example, when the pointed end of the inverted horn-shaped reflector 30 reaches the light emitting element 20 So that more rigid fixing and accurate height adjustment can be made possible.

FIG. 9 is a perspective view showing a backlight unit according to still another embodiment of the present invention, and FIG. 10 is a plan view showing the backlight unit of FIG.

9 and 10, the fixing member 40 of the backlight unit according to still another embodiment of the present invention is installed on the upper part of the inverted horn-shaped reflector 30, and the through hole H And at least three vertical leg portions 44 provided along the inner diameter surface of the vertical leg portion 44.

10, the vertical legs 44 may be formed so as to center the radiation L on the light emitting device 20 so as to minimize the light shielding area generated by the light emitting device 20. [ And an edge portion may be a plate-shaped blade provided toward the light emitting element 20. [0050]

The vertical leg portions 44 are formed on the inner surface of the through hole H of the light guide plate 10 so that the vertical leg portions 44 can be more firmly fixed to the through hole H. [ Can be contacted with the surface.

Therefore, as shown in FIGS. 9 and 10, the inverted horn-shaped reflector 30 can be more firmly and stably fixed to the through hole H by using the vertical leg portions 44.

11 is an enlarged cross-sectional view illustrating a backlight unit according to still another embodiment of the present invention.

11, the backlight unit according to still another embodiment of the present invention may further include an optical system 50 installed on a flat upper surface of the inverted horn-

Here, the optical system 50 may include a partial reflection layer 51 having a constant thickness and a total reflection layer 52 provided on the partial reflection layer 52, as shown in FIG.

Therefore, the optical system 50 may be appropriately disposed to emit a part of the light passing through the inside of the inverted horn-shaped reflector 30 as a light-transmitting material upwardly to precisely control the formation of the name portion or the dark portion have.

The optical system 50 may include various diffusion layers, optical filter layers, prism sheet layers, scattering layers, refraction layers, metal layers, Bragg reflection layers, and the like in addition to the partial reflection layer 51 and the partial reflection layer 52 described above. , An air gap, and a combination thereof.

Although not shown, the light emitting device 20 may be provided with a phosphor, a light-transmitting encapsulant, or a mixture thereof.

Here, the phosphor may have the following composition formula and color.

Oxide system: yellow and green Y3Al5O12: Ce, Tb3Al5O12: Ce, Lu3Al5O12: Ce

(Ba, Sr) 2SiO4: Eu, yellow and orange (Ba, Sr) 3SiO5: Ce

Eu, Sr2Si5N8: Eu, SrSiAl4N7: Eu, Eu3O3: Eu, Eu3O3: Eu,

The composition of the phosphor should basically correspond to stoichiometry, and each element may be substituted with another element in each group on the periodic table. For example, Sr can be substituted with Ba, Ca, Mg, etc. of the alkaline earth (II) group, and Y can be replaced with lanthanum series of Tb, Lu, Sc, Gd and the like. Ce, Tb, Pr, Er, Yb and the like, and the active agent may be used alone or as a negative active agent for the characteristic modification.

As a substitute for the phosphor, materials such as a quantum dot may be used. Alternatively, a fluorescent material and QD may be mixed with the LED or used alone.

QD can be composed of a core (3 to 10 nm) such as CdSe and InP, a shell (0.5 to 2 nm) such as ZnS and ZnSe, and a ligand for stabilizing the core and the shell. Can be implemented.

In addition, the coating method of the fluorescent material or the quantum dot may include at least one of a method of being applied to an LED chip or a light emitting device, a method of covering the material in a film form, a method of attaching a sheet form such as a film or a ceramic fluorescent material .

Dispensing and spray coating are common methods of spraying, and dispensing includes mechanical methods such as pneumatic method and screw, linear type. It is also possible to control the amount of dyeing through a small amount of jetting by means of a jetting method and control the color coordinates thereof. The method of collectively applying the phosphor on the wafer level or the light emitting device substrate by the spray method can easily control productivity and thickness.

The method of directly covering the light emitting device or the LED chip in a film form can be applied by a method of electrophoresis, screen printing or phosphor molding, and the method can be different according to necessity of application of the side of the LED chip.

In order to control the efficiency of the long-wavelength light-emitting phosphor that reabsers light emitted from a short wavelength among two or more kinds of phosphors having different emission wavelengths, two or more kinds of phosphor layers having different emission wavelengths can be distinguished. A DBR (ODR) layer may be included between each layer to minimize absorption and interference.

In order to form a uniform coating film, the phosphor may be formed into a film or ceramic form and then attached onto the LED chip or the light emitting device.

In order to make a difference in light efficiency and light distribution characteristics, a photoelectric conversion material may be located in a remote format. In this case, the photoelectric conversion material is located together with a transparent polymer, glass, or the like depending on its durability and heat resistance.

Since the phosphor coating technique plays a major role in determining the optical characteristics in the light emitting device, control techniques such as the thickness of the phosphor coating layer and the uniform dispersion of the phosphor have been studied variously. QD can also be placed in the LED chip or the light emitting element in the same manner as the phosphor, and can be positioned between the glass or translucent polymer material for light conversion.

The translucent encapsulant may be at least one selected from the group consisting of EMC, an epoxy resin composition, a silicone resin composition, a modified epoxy resin composition, a modified silicone resin composition, a polyimide resin composition, a modified polyimide resin composition, a polyphthalamide (PPA), a polycarbonate resin, At least one of phenylene sulfide (PPS), liquid crystal polymer (LCP), ABS resin, phenol resin, acrylic resin, PBT resin, Bragg reflection layer, air gap, total reflection layer, metal layer, As shown in FIG.

The transparent encapsulant may be applied to the light emitting device 20 in the form of a paste or may be laminated using a separate lamination process or may be formed by pressing the sheet material.

On the other hand, although not shown, the present invention may include a lighting apparatus including the aforementioned backlight unit. Here, the components of the lighting apparatus according to some embodiments of the present invention may have the same configuration and functions as those of the above-described light emitting device package of the present invention. Therefore, detailed description is omitted.

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the invention. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

H: Through hole
S: substrate
P: Display panel
10: light guide plate
11, 12: flange groove
20: Light emitting element
30: inverted horn reflector
30a:
40: Fixing member
41, 42, 43: flange portion
42a: opening
44: vertical leg
D: Driver home
L: Radiation
50: Optical system
51: partial reflection layer
52: total reflection layer
100: Backlight unit

Claims (10)

A light guide plate formed of at least one through hole and made of a light transmitting material;
A light emitting element provided in a through hole of the light guide plate; And
An inverted cone-shaped reflector inserted into the through-hole of the light guide plate to guide the light generated from the light emitting device toward the light guide plate, the upper portion being flat and the lower portion being formed into a pointed cone;
And a backlight unit. The method according to claim 1,
A fixing member installed between the light guide plate and the inverted horn-shaped reflector and fixing the inverted horn-shaped reflector to the through hole of the light guide plate;
Further comprising a backlight unit. 3. The method of claim 2,
The inverted horn-shaped reflector has a shape filled with the inside,
Wherein the fixing member is a flange portion provided on an upper surface of the inverted horn-shaped reflector and contacting a peripheral portion of the through hole of the light guide plate. The method of claim 3,
Wherein the flange portion has a shape corresponding to the flange portion at a peripheral portion of the through hole so that the flange portion can be seated. 5. The method of claim 4,
The inverted cone reflector is inverted cone,
Wherein the flange portion is a disc-shaped ring-shaped metal made of metal having an opening formed at the center thereof. The method according to claim 1,
Wherein the fixing member is at least three or more vertical legs provided on the inverse horn-shaped reflector and along the inner diameter surface of the through hole. The method according to claim 6,
Wherein the vertical legs are plate-shaped blades that are arranged on the radiation with the light emitting element as a center, the edge portions being directed toward the light emitting element,
And an outer side surface of the vertical legs is in contact with an inner diameter surface of the through hole of the light guide plate. The method according to claim 1,
Wherein the inverted horn-shaped reflector is a translucent material having an opaque material having a reflective surface formed on an outer surface thereof or a reflective surface formed on an outer surface thereof. The method according to claim 1,
And an optical system provided on a flat upper surface of the inverted horn-shaped reflector,
The optical system may be any of a partial reflection layer having at least a constant thickness, a total reflection layer, a diffusion layer, an optical filter layer, a prism sheet layer, a scattering layer, a refraction layer, a metal layer, a Bragg reflection layer, an air gap, Wherein the backlight unit is formed by selecting one or more light sources. A light guide plate formed of at least one through hole and made of a light transmitting material;
A light emitting element provided in a through hole of the light guide plate; And
An inverted cone-shaped reflector inserted into the through-hole of the light guide plate to guide the light generated from the light emitting device toward the light guide plate, the upper portion being flat and the lower portion being formed into a pointed cone;
.

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