KR20150048580A - Light emitting device package, backlight unit, illumination device and its manufacturing method - Google Patents

Abstract

The present invention relates to a light emitting package which can change an LED point light source into a surface light source by inducing the light generated in a light emitting device, a backlight unit, a lighting device, and a method for manufacturing a light emitting device package which comprises a substrate; a light emitting device mounted on the substrate; a transparent sealant installed on the substrate to surround the light emitting device; and an optical system installed on the upper surface of the transparent sealant to induce the light toward the side of the transparent sealant.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light emitting device package, a backlight unit, an illumination device,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light emitting device package, a backlight unit, an illumination device, and a method of manufacturing a light emitting device package, and more particularly, A light emitting device package, a backlight unit, a lighting device, and a method of manufacturing a light emitting device package.

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, has a strong directivity of light, and can be driven at a low voltage. Further, such an LED is resistant to impact and vibration, does not require preheating time and complicated driving, can be packaged in various forms, can be modularized for various purposes, and can be applied to various lighting devices and display devices.

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.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide an optical system for guiding light emitted upward from a light emitting device to a side, A light emitting device package capable of reducing the thickness of the product, preventing a mura phenomenon of the display device, a luminance deviation and a color deviation, thereby improving optical characteristics and producing a good quality product, and a backlight unit An illumination device, and a method of manufacturing a light emitting device package. 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 light emitting device package including: a substrate; A light emitting element mounted on the substrate; A transparent encapsulant provided on the substrate so as to surround the periphery of the light emitting element; And an optical system provided on an upper surface of the transparent encapsulant to guide light in a lateral direction of the transparent encapsulant.

According to an aspect of the present invention, the optical system may include a diffraction groove portion in which a plurality of diffraction grooves having a diffraction interval are formed on an upper surface of the transparent encapsulant.

According to an aspect of the present invention, the diffraction grooves may be formed by etching the transparent encapsulant.

According to an aspect of the present invention, the optical system may further include a filling layer filled in the diffraction groove of the diffraction groove portion and made of a material different from the transparent sealing material.

According to an aspect of the present invention, the optical system may include a total reflection layer provided on an upper surface of the transparent encapsulant.

According to an aspect of the present invention, the diffraction interval of the diffraction grooves may be larger toward the center and smaller toward the rim.

According to an aspect of the present invention, the diffraction interval of the diffraction grooves may be smaller toward the center and larger toward the edge.

According to an aspect of the present invention, the diffraction grooves may be a plurality of circular patterns of concentric circles.

According to another aspect of the present invention, there is provided a backlight unit comprising: a substrate; A light emitting element mounted on the substrate; A transparent encapsulant provided on the substrate so as to surround the periphery of the light emitting element; An optical system provided on an upper surface of the transparent encapsulant so as to guide light in a lateral direction of the transparent encapsulant; And a light guide plate installed in a path of light generated in the light emitting device.

According to another aspect of the present invention, there is provided a method of manufacturing a light emitting device package, the method comprising: placing a light emitting device on a substrate; Injection molding an optical system integrally on the upper surface of the transparent encapsulant so that the transparent encapsulant is injection-molded so as to surround the periphery of the light emitting element and light can be guided laterally of the transparent encapsulant; And applying a total reflection layer on the optical system.

According to an aspect of the present invention, there is provided a lighting apparatus comprising: a substrate; A light emitting element mounted on the substrate; A transparent encapsulant provided on the substrate so as to surround the periphery of the light emitting element; And an optical system provided on an upper surface of the transparent encapsulant to guide light in a lateral direction of the transparent encapsulant.

According to some embodiments of the present invention as described above, the thickness of the product can be reduced, the point light source can be changed to the surface light source, and the optical characteristics of the product can be improved, thereby preventing product defects. Of course, the scope of the present invention is not limited by these effects.

1 is a cross-sectional view illustrating a light emitting device package according to some embodiments of the present invention.
2 is a plan view showing the light emitting device package of FIG.
3 is a perspective view showing the light emitting device package of FIG.
4 is an enlarged sectional view showing the diffraction grooves and the diffraction grooves in Fig. 1 in an enlarged manner.
5 is an enlarged cross-sectional view showing an enlarged view of a filling layer according to another example of FIG.
6 is an enlarged sectional view showing an enlarged view of the total reflection layer according to still another example of FIG.
7 is a plan view showing a light emitting device package according to another example of FIG.
8 is a cross-sectional view illustrating a backlight unit according to some embodiments of the present invention.
9 is a flowchart showing a method of manufacturing a light emitting device package according to some embodiments 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 cross-sectional view illustrating a light emitting device package 100 according to some embodiments of the present invention. 2 is a plan view showing the light emitting device package 100 of FIG. 1, FIG. 3 is a perspective view showing the light emitting device package 100 of FIG. 1, and FIG. 4 is a cross- (41) in an enlarged scale.

1 to 4, a light emitting device package 100 according to some embodiments of the present invention includes a substrate 10, a light emitting device 20, a transparent encapsulant 30, And an optical system 40.

The substrate 10 can receive the light emitting device 20 and is electrically connected to the light emitting device 20. The substrate 10 may have appropriate mechanical strength and insulation property to support the light emitting device 20, Or a conductive material.

For example, the substrate 10 may include various wiring layers to connect the light emitting device 20 with an external power source, and may include a printed circuit board (PCB) having a plurality of epoxy resin sheets formed thereon, Lt; / RTI > The substrate 10 may be a Flexible Printed Circuit Board (FPCB) made of a flexible material.

In addition, the substrate 10 may be a synthetic resin substrate such as a resin or a glass epoxy or a ceramic substrate in consideration of a thermal conductivity. In addition, the substrate 10 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 10 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.

In addition, although not shown in the figure, the wiring layer may be provided in the form of a conductive layer pattern. The wiring layer may be made of at least one selected from copper, aluminum, and combinations thereof, which are excellent in thermal conductivity and relatively inexpensive materials.

At this time, such a pattern forming method may be thermocompression processing, plating processing, adhesive processing, sputtering processing, other etching processing, printing processing, spray processing and the like.

In addition, the light emitting device 20 may be mounted on the substrate 10, and FIG. 1 illustrates a state in which one light emitting device 20 is mounted on the substrate 10.

In addition, a plurality of light emitting devices 20 may be mounted on the substrate 10.

The light emitting device 20 may be formed of a semiconductor. 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 ZrB ₂ , HfB _2, ZrN, HfN and TiN may be used as needed. Further, a plurality of layers may be combined, or the composition may be gradually changed.

Further, although not shown, the light emitting device 20 may be a flip chip type light emitting device having a signal transmitting medium such as a bump, a pad, or a solder. In addition, the light emitting device 20 may be a vertical type or a horizontal type And the like can be applied.

1 to 3, the transparent encapsulant 30 is disposed on the substrate 10 so as to surround the light emitting device 20, And may be installed in a light path of the light emitting device 20 so as to cover and protect the upper surface and the side surface of the light emitting device 20.

The transparent encapsulant 30 may be, for example, a cylinder as a whole as shown in Fig. In addition, the transparent encapsulant 30 may be in a wide variety of shapes such as a triangular prism, a quadrangular prism, a pentagonal prism, a hexagonal prism, a polygonal prism, an elliptical prism, a composite prism, and a geometric prism. Accordingly, the shape of the encapsulant 30 of the light emitting device package 100 according to some embodiments of the present invention is not limited to the shapes shown in Figs.

The transparent encapsulant 30 may be molded on the substrate 10, or may be dispensed or screen-printed.

More specifically, for example, the transparent encapsulant 30 may be 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 and 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.

1 to 4, the optical system 40 may be installed on the upper surface of the transparent encapsulant 30 so as to guide the light in the lateral direction of the transparent encapsulant 30 have.

For example, as shown in FIGS. 1 to 4, the optical system 40 includes a plurality of diffraction grooves 41a having a diffraction interval P1 (P2) on the upper surface of the transparent encapsulant 30 And a diffraction groove portion 41 formed thereon.

More specifically, for example, the diffraction groove 41a may be formed by dry or wet etching or laser etching the transparent encapsulant 30 molded and molded.

Here, as shown in FIG. 4, the diffraction groove 41a may serve to diffract light to guide the light emitting device 20 in the lateral direction. The diffraction grooves 41a can adjust the amount of light diffracted by the diffraction interval.

The diffraction grooves 41a are optimized in terms of the shape of the cross section, the depth, the width, the diffraction interval, and the installation angle in accordance with the material and density of the rotary groove 41 and the transparent sealing material 30 . Also, the diffraction groove 41a can be designed optimally in accordance with the wavelength, type, color, light emission angle, and the like of the light emitted from the light emitting device 20.

In FIG. 4, the bottom surface of the diffraction groove 41a is shown as a flat plane, and the cross section of the diffraction groove 41a as a whole is illustrated as a groove. However, the diffraction groove 41a may have a circular groove, Triangular grooves, polygonal grooves, serrated grooves, etc., and its depth, width, diffraction interval, and installation angle can also be optimally applied.

Therefore, the light generated in the light emitting device 20 can be entirely diffracted by the diffraction grooves 41a formed above the transparent encapsulant 30 and guided in the lateral direction of the light emitting device 20 .

Therefore, even if a separate secondary lens is not provided, the light emitted from the light emitting element 20 can be emitted to the side of the light emitting element 20 using the diffraction groove portion 41 provided above the transparent encapsulant 30 And the surface light source can be changed as a whole as a point light source, so that the thickness of the product can be reduced, and a mura phenomenon intensively generated above the light emitting device 20, a luminance deviation and a color deviation Thereby improving the optical characteristics and producing high quality products.

FIG. 5 is an enlarged cross-sectional view showing an enlarged view of the filling layer 42 according to another example of FIG.

5, the optical system 40 is not limited to the above-described diffraction groove 41, and the optical system 40 is configured to fill the diffraction groove 41a of the diffraction groove 41, And may further include a filling layer 42 having a different material or a different density from the transparent encapsulant 30.

The filling layer 42 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) (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, a metal layer and a combination thereof May be selected.

The filling layer 42 may be applied to the upper surface of the transparent encapsulant 30 in the form of a paste or may be laminated using a separate lamination process or may be formed by pressing the sheet material.

Therefore, when light that is not diffracted reaches the filling layer 42 except the light diffracted by the diffraction groove 41a of the diffraction groove 41 and guided in the lateral direction of the light emitting device, May be reflected and guided in the lateral direction of the light emitting device by the light emitting device 42.

At this time, the reflectance of light reflected by the filling layer 42 may vary depending on the material and the density of the filling layer 42. In addition, the reflectance may vary depending on the wavelength, type, color, light emission angle, and the like of the light emitted from the light emitting element 20. Therefore, the material and density of the filling layer 42 can be optimized and designed in accordance with the above-described environmental conditions.

FIG. 6 is an enlarged cross-sectional view showing an enlarged view of the total reflection layer 43 according to still another example of FIG.

As shown in FIG. 6, the optical system 40 may include a total reflection layer 43 provided on the upper surface of the transparent encapsulant 30.

Here, the total reflection layer 43 may have the same or different material density as that of the filling layer 42.

That is, the total reflection layer 43 is formed of 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, a metal layer and a combination thereof May be selected.

The total reflection layer 43 may be applied on the upper surface of the transparent encapsulant 30 in the form of a paste or may be laminated using a separate lamination process or may be formed by pressing the sheet material.

Therefore, when light that is not diffracted reaches the filling layer 42 except the light diffracted by the diffraction groove 41a of the diffraction groove 41 and guided in the lateral direction of the light emitting device, The light that is not reflected by the filler layer 42 is totally reflected by the total reflection layer 43 to be reflected by the light emitting element 20, (Not shown).

At this time, the reflectance of light reflected by the total reflection layer 43 may vary depending on the material and density of the total reflection layer 43, and the like. In addition, the reflectance may vary depending on the wavelength, type, color, light emission angle, and the like of the light emitted from the light emitting element 20. Therefore, the material, density, and the like of the total reflection layer 43 can be optimized and designed in accordance with the above-described environmental conditions.

Although not shown, a metallic reflective layer may be provided on the lower surface of the light emitting device 20, the lower surface of the transparent encapsulant 30, or the upper surface of the substrate 10.

2, the diffraction interval of the diffraction grooves 41a is set such that the diffraction interval P2 is gradually increased toward the center of the diffraction groove 41a in order to improve the uniformity of the light and to prevent blurring phenomenon, luminance deviation, color deviation, And the diffraction interval P1 becomes smaller as it goes toward the edge portion.

Further, as shown in Fig. 2, the diffraction grooves 41a may be a plurality of circular patterns of concentric circles. The present invention is not limited to the circular pattern, and various other patterns such as a triangular pattern, a square pattern, a polygonal pattern, an elliptical pattern, a composite pattern, and a geometric pattern may be applied.

The shape and specific numerical values of the diffraction intervals P1 and P2 can be designed optimally in various shapes depending on the material, density, thickness, light characteristics, and the like of the parts.

7 is a plan view showing a light emitting device package according to another example of FIG.

As shown in Fig. 7, according to various environmental conditions, the diffraction interval P3 of the diffraction groove 41a becomes smaller toward the center, and the diffraction interval P4 becomes larger toward the edge of the diffraction groove 41a .

The shape and the specific numerical value of the diffraction interval P3 (P4) can be designed optimally in various shapes according to the material, the density, the thickness, the light characteristic, etc. of the parts.

8 is a cross-sectional view illustrating a backlight unit 1000 according to some embodiments of the present invention.

8, a backlight unit 1000 according to some embodiments of the present invention includes a substrate 10, a light emitting device 20 that is seated on the substrate 10, A transparent encapsulant 30 provided on the substrate so as to surround the transparent encapsulant 30 and an optical system 40 installed on the upper surface of the transparent encapsulant 30 to guide light in a lateral direction of the transparent encapsulant 30 And a light guide plate 50 installed in a path of light generated in the light emitting device 20.

Here, the substrate 10, the light emitting device 20, the transparent encapsulant 30, and the optical system 40 are formed on the substrate 10 of the light emitting device package 100 described above, The light emitting device 20, the transparent encapsulant 30, and the optical system 40 described above. Therefore, detailed description is omitted.

The backlight unit 1000 is installed on an LCD panel and projects light toward the LCD panel. The backlight unit 1000 is installed in a path of light generated by the light emitting device 20, The light can be transmitted over a larger area.

The light guide plate 50 may be made of polycarbonate, polysulfone, polyacrylate, polystyrene, polyvinyl chloride, polyvinyl alcohol, polynorbornene, polyester, or the like , Besides, materials of various translucent resin series can be applied. The light guide plate 50 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.

The backlight unit 1000 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 50. [

On the other hand, although not shown, a phosphor may be provided around the light emitting element 20. For example, such a 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.

9 is a flowchart showing a method of manufacturing a light emitting device package 100 according to some embodiments of the present invention.

1 to 9, a method of fabricating a light emitting device package 100 according to some embodiments of the present invention includes the steps of: (S1) placing a light emitting device 20 on a substrate 10; A transparent encapsulant 30 is injected and molded on the substrate 10 so as to surround the periphery of the luminous means 20 and the transparent encapsulant 30, (S2) of integrally molding an optical system (40) on the upper surface of the substrate (30) and applying a total reflection layer (43) on the optical system (40).

On the other hand, although not shown, the present invention can include a lighting device including the light emitting device packages described above. 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.

10: substrate
20: Light emitting element
30: transparent sealing material
40: Optical system
41: Diffraction groove
41a: diffractive groove
42: filling layer
43: total reflection layer
50: light guide plate
100: Light emitting device package
P1, P2, P3, P4: diffraction interval
1000: Backlight unit

Claims (11)

Board;
A light emitting element mounted on the substrate;
A transparent encapsulant provided on the substrate so as to surround the periphery of the light emitting element; And
An optical system provided on an upper surface of the transparent encapsulant so as to guide light in a lateral direction of the transparent encapsulant;
Emitting device package. The method according to claim 1,
The optical system includes:
A diffraction groove portion in which a plurality of diffraction grooves having a diffraction interval are formed on an upper surface of the transparent encapsulant;
Emitting device package. 3. The method of claim 2,
And the diffraction grooves are formed by etching the transparent encapsulant. 3. The method of claim 2,
The optical system includes:
A filling layer filled in the diffraction groove of the diffraction groove portion and made of a material different from the transparent sealing material;
Emitting device package. 3. The method according to claim 1 or 2,
The optical system includes:
A total reflection layer provided on an upper surface of the transparent encapsulant;
Emitting device package. 3. The method of claim 2,
And the diffraction interval of the diffraction grooves becomes larger toward the central portion and smaller toward the rim portion. 3. The method of claim 2,
And the diffraction interval of the diffraction groove becomes smaller toward the center and becomes larger toward the rim. 3. The method of claim 2,
Wherein the diffraction grooves are a plurality of circular patterns of concentric circles. Board;
A light emitting element mounted on the substrate;
A transparent encapsulant provided on the substrate so as to surround the periphery of the light emitting element;
An optical system provided on an upper surface of the transparent encapsulant so as to guide light in a lateral direction of the transparent encapsulant; And
A light guide plate installed in a path of light generated in the light emitting device;
And a backlight unit. Placing a light emitting element on a substrate;
Injection molding an optical system integrally on the upper surface of the transparent encapsulant so that the transparent encapsulant is injection-molded so as to surround the periphery of the light emitting element and light can be guided laterally of the transparent encapsulant; And
Applying a total reflection layer on the optical system;
Emitting device package. Board;
A light emitting element mounted on the substrate;
A transparent encapsulant provided on the substrate so as to surround the periphery of the light emitting element; And
An optical system provided on an upper surface of the transparent encapsulant so as to guide light in a lateral direction of the transparent encapsulant;
.

Images