KR101797596B1 - Light emitting device package and lighting apparatus including the same - Google Patents

Abstract

An embodiment includes a heat transfer member forming a cavity; A first conductive layer and a second conductive layer that are in contact with the heat transfer member with an insulating layer interposed therebetween and are electrically isolated from each other; And a light emitting element disposed in the cavity and electrically connected to the first conductive layer and the second conductive layer, respectively, wherein a first conductive layer and a second conductive layer corresponding to an outer region of the cavity have steps And a light emitting device package.

Description

TECHNICAL FIELD [0001] The present invention relates to a light emitting device package, and a lighting system including the light emitting device package.

Embodiments relate to a light emitting device package and an illumination system including the same.

BACKGROUND ART Light emitting devices such as a light emitting diode (LED) or a laser diode (LD) using semiconductor materials of Group 3-5 or 2-6 group semiconductors have been developed with thin film growth technology and device materials, Green, blue, and ultraviolet rays. By using fluorescent materials or combining colors, it is possible to realize white light rays with high efficiency. Also, compared to conventional light sources such as fluorescent lamps and incandescent lamps, low power consumption, It has the advantages of response speed, safety, and environmental friendliness.

Therefore, a transmission module of the optical communication means, a light emitting diode backlight replacing a cold cathode fluorescent lamp (CCFL) constituting a backlight of an LCD (Liquid Crystal Display) display device, a white light emitting element capable of replacing a fluorescent lamp or an incandescent lamp Diode lighting, automotive headlights, and traffic lights.

BACKGROUND ART A light emitting device package in which a light emitting element is mounted on a package body and is electrically connected is widely used in a lighting device or a display device.

Embodiments improve the heat dissipation characteristics of the light emitting device package and the lighting system including the same and improve the stability of the light emitting device included in the cavity of the light emitting device package.

An embodiment includes a heat transfer member forming a cavity; A first conductive layer and a second conductive layer that are in contact with the heat transfer member with an insulating layer interposed therebetween and are electrically isolated from each other; And a light emitting element disposed in the cavity and electrically connected to the first conductive layer and the second conductive layer, respectively, wherein a first conductive layer and a second conductive layer corresponding to an outer region of the cavity have steps And a light emitting device package.

The heat transfer member may have at least one stepped portion at a portion corresponding to an outer region of the cavity, and the insulating layer, the first conductive layer, and the second conductive layer may have steps similar to those of the heat transfer member.

Another embodiment includes a heat transfer member forming a cavity; A first conductive layer and a second conductive layer that are in contact with the heat transfer member with an insulating layer interposed therebetween and are electrically isolated from each other; And a light emitting element disposed in the cavity and electrically connected to the first conductive layer and the second conductive layer, respectively, wherein the heat transfer member corresponding to an outer region of the cavity has a stepped portion formed therein do.

The first conductive layer and the second conductive layer are each formed with a step at a portion corresponding to an outer region of the cavity, and the heat transfer member and the insulating layer have the same steps as the first conductive layer and the second conductive layer, Lt; / RTI >

The circuit board may further include a circuit board connected to the first conductive layer and the second conductive layer through a conductive adhesive agent. The thickness of the conductive adhesive agent may be less than or equal to the depth of the stepped portion.

The bottom surface of the circuit board may be at the same height or at a lower height as the top surface of the first conductive layer / second conductive layer in contact with.

And a resin layer filled in the cavity and surrounding the light emitting element.

The edge of the resin layer may be formed to be equal to or lower than the uppermost end of the cavity.

The first and second conductive layers may be disposed at least partially higher in a region between the edge of the resin layer and the conductive adhesive.

Another embodiment includes a heat transfer member forming a cavity; A first conductive layer and a second conductive layer that are in contact with the heat transfer member with an insulating layer interposed therebetween and are electrically isolated from each other; A light emitting element disposed in the cavity and electrically connected to the first conductive layer and the second conductive layer, respectively; And a pair of circuit boards each of which is connected to the first conductive layer and the second conductive layer by a conductive adhesive agent, wherein a maximum height of the first conductive layer and the second conductive layer between the cavity and the circuit board, Thereby providing a light emitting device package higher than the highest height of the adhesive.

And a resin layer filled in the cavity and surrounding the light emitting element, wherein a maximum height of the first conductive layer and the second conductive layer between the cavity and the circuit board may be higher than a maximum height of the resin layer.

Yet another embodiment provides an illumination system in which the above-described light emitting device package is disposed.

The light emitting device package according to the embodiment and the lighting system including the same improve the heat dissipation property and improve the stability of the light emitting device disposed in the light emitting device package.

1 is a view showing a first embodiment of a light emitting device package,
FIGS. 2 and 3 are enlarged views of the portion 'A' in FIG. 1,
FIGS. 4 to 10 illustrate a method of manufacturing the light emitting device package of FIG. 1,
11 is a view showing an embodiment of a light emitting device package array,
FIG. 12 is an enlarged view of a part of the light emitting device package array of FIG. 11,
13 is a sectional view taken along the 'A' direction and the 'B' direction in FIG. 12,
14A to 14F are views showing an embodiment of the manufacturing method of the second embodiment of the light emitting device package,
15 and 16 are views showing a third embodiment and a fourth embodiment of the light emitting device package,
17A and 17B are a plan view and a sectional view of a fifth embodiment of the light emitting device package,
18A and 18B are a plan view and a cross-sectional view of a sixth embodiment of the light emitting device package,
19 is a view showing an embodiment of a lighting apparatus including a light emitting device package,
20 is a view showing an embodiment of a display device including a light emitting device package.

BRIEF DESCRIPTION OF THE DRAWINGS The above and other objects, features and advantages of the present invention will be more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which: FIG.

In the description of the embodiments, it is to be understood that each layer (film), region, pattern or structure is formed "on" or "under" a substrate, each layer The terms " on "and " under " encompass both being formed" directly "or" indirectly " In addition, the criteria for above or below each layer will be described with reference to the drawings.

The thickness and size of each layer in the drawings are exaggerated, omitted, or schematically shown for convenience and clarity of explanation. Also, the size of each component does not entirely reflect the actual size.

1 is a view showing a first embodiment of a light emitting device package.

In the light emitting device package according to the embodiment, the light emitting device 240 is disposed in a cavity formed in the heat transfer member 210. The light emitting device 240 may include a vertical light emitting device, a horizontal light emitting device, and a flip chip type light emitting device. As the heat transfer member 210, a material having excellent thermal conductivity may be used. For example, copper (Cu) or aluminum may be used.

The light emitting device 240 may be disposed on the bottom surface of the cavity formed in the heat transfer member 210, and the side walls of the cavity may be formed vertically. In the present embodiment, the width of the side wall of the cavity increases toward the upper side with reference to the drawing, and the size of the cavity gradually increases.

Although the heat transfer member 210 constituting the cavity is bent at a sharp angle, it may be bent in a streamlined manner as shown in Figs. 9 and 10, for example.

An insulating layer 220 is formed on the heat transfer member 210. The insulating layer 220 may be formed of polyimide as an example. The insulating layer 220 may be patterned to expose at least a portion of the heat transfer member 210 on the bottom surface of the cavity. That is, the material forming the insulating layer 220 may not be formed on at least a part of the bottom surface of the cavity.

The heat transfer member 210 may be superimposed on the substrate 100 through the adhesive layer 110. The substrate 100 may serve as a body of the light emitting device package, and may function as a bracket for supporting the light source module in the backlight unit when made of metal.

The adhesive layer 110 is excellent in thermal conductivity and can bond the substrate 100 and the heat transfer member 210. The heat emitted from the light emitting device 240 is directly transferred to the substrate 100 such as a bracket through the heat transfer member 210 so that the heat dissipation efficiency is improved by not using the PPA resin in the backlight unit, .

The first conductive layer 230 and the second conductive layer 230 are formed with the insulating layer 220 interposed therebetween. As described later, the first and second conductive layers 230 form a current through the light emitting device 240 So that it can be electrically isolated from the heat transfer member 210 by the insulating layer 220. That is, the first and second conductive layers 230 and 230 may not be electrically connected through the heat transfer member 210.

The first and second conductive layers 230 may be made of a copper foil or the like including copper and contact the heat transfer member 210 through the insulating layer 220 so that the heat transfer member 210 and the insulating layer 220 And the first and second conductive layers 230 may have the same shape.

The light emitting device 240 is electrically connected to the first and second conductive layers 230. For example, a wire 250 is bonded. The resin layer 260 is filled in the cavity to protect the light emitting device 240 and the wire 250.

At this time, the resin layer 260 includes a phosphor to change the wavelength of light emitted from the light emitting device 240. Since the resin layer 260 is filled in the cavity, the edge of the resin layer 260 may be formed lower than the top of the cavity.

The heat transfer member 210 is horizontally disposed at an upper portion of the outer periphery of the cavity. The heat transfer member 210 is disposed horizontally on the heat transfer member 210, between the insulating layer 220 and the first and second conductive layers 230 And the circuit board 270 is connected.

The circuit board 270 may be coupled to the first and second conductive layers 230 through the conductive adhesive 280. The circuit board 270 may be a printed circuit board, or may be a metal PCB such as MPCB or MCPCB.

FIGS. 2 and 3 are enlarged views of a portion 'A' in FIG.

As shown in the drawing, the heat transfer member 210 has a stepped portion at a portion corresponding to an outer region of the cavity, so that a height of the heat transfer member 210, which is adjacent to the cavity, (210) is formed to have a lower height.

The insulating layer 220 and the first and second conductive layers 230 are patterned in the same manner as the heat transfer member 210 and have a stepped portion because the heat transfer member 210 is formed with a step.

The circuit board 280 is electrically connected to the first and second conductive layers 230 through the conductive adhesive 270 and disposed at a lower region of the step of the heat transfer member 210. That is, the circuit board 280 is disposed in a lower region of the step of the first and second conductive layers 230.

In this structure, the heat transfer member 210 to the first and second conductive layers 230 are formed higher between the resin layer 260 in the cavity and the conductive adhesive agent 270 / circuit board 280, The second conductive layer 260 or the conductive adhesive agent 270 in the out-of-cavity region may not flow over the first conductive layer 230.

In particular, if the maximum height of the first and second conductive layers 230 between the cavity and the circuit board 280 is higher than the highest height of the conductive adhesive agent 270 and / or the resin layer 260, The flow of the conductive adhesive agent 270 and the resin layer 260 can be prevented.

The structure of the step is described in detail as follows. 2, the heat transfer member 210 includes a first end 210a of the upper region of the step, a second end 210c of the lower region of the step, a connection 210 connecting the first end 210a and the second end 210c, Stage 210b.

The first and second conductive layers 230 are patterned along the step of the heat transfer member 210 to form a first end 230a of the upper region of the step and a second end 230c of the lower region of the step, And a connection end 230b connecting the second end 230a and the second end 230c.

The insulating layer 220 is disposed between the soft conductive member 210 and the first and second conductive layers 230 so that the heat conductive member 210 and the first and second conductive layers 230 A connecting end 220b connecting the first end 220a of the upper region of the step to the second end 220c of the lower region of the step and the first end 220a and the second end 220c, Lt; / RTI >

The thickness of the conductive adhesive 270 connecting the circuit board 280 to the first and second conductive layers 230 may be less than the depth of the step to prevent the conductive adhesive 270 from flowing into the cavity. That is, due to the thickness of the conductive adhesive 270, the bottom surface of the circuit board 280 may be the same height as the upper surface of the first and second conductive layers 230 to be contacted, or may be disposed at a lower height.

The depth of the step in Fig. 3, t _c can be defined as a and the thickness of the conductive adhesive 270 is t _s can be defined as, since the size or less of t _s size is t _c of the conductive adhesive 270, the first , And does not flow in the cavity direction beyond the second conductive layer (230).

The thickness ts of the conductive adhesive agent 270 is set such that the height h _p of the conductive adhesive agent 270 in contact with the circuit board 280 and the height h h of the conductive adhesive agent 270 in contact with the first and second conductive layers 230, _c ).

Although not shown, a reflective layer may be formed on the first and second conductive layers 230 in the cavity. The reflective layer reflects light emitted from the light emitting device 240 and transmits the light to the outside of the cavity. Ag) or the like can be coated.

4 to 10 are views showing an embodiment of a method of manufacturing the light emitting device package of FIG.

First, an insulating layer 220 and a conductive layer 230 are formed on a base substrate 290 as shown in FIG. At this time, the insulating layer 220 may be fixed to the base substrate 290 using an adhesive 295.

Here, as the conductive layer 230 to which the insulating layer 220 is adhered, a copper foil having a polyimide film bonded thereto can be used. The polyimide has a thickness of only 5 micrometers (탆) and is very advantageous in heat resistance .

As shown in FIG. 5, a mask 300 is selectively formed on the conductive layer 230, and the conductive layer 230 is patterned using the mask 300 as shown in FIG. 6, The first and second conductive layers 230 may be separated into two and then the first and second conductive layers, respectively.

7, the insulating layer 220, the base substrate 290, and the adhesive 295 may be patterned in the same manner as the conductive layer 230. The region where the insulating layer 220 or the like is removed in the center of FIG. 7 corresponds to the bottom surface of the cavity in FIG.

8, the base substrate 290 is removed, and the heat transfer member 210 is bonded to the insulating layer 220. As shown in FIG. At this time, the conventional adhesive 295 may be used, or an adhesive 295 may be further used. The base substrate 290 acts as a stiffener in the manufacturing process and is then removed.

The insulating layer 220 and the adhesive 295 are provided in two layers between the heat transfer member 210 and the conductive layer 230 and the polyimide or the like is responsible for electrical insulation and the adhesive 295 performs adhesion, And as a result, the heat conduction characteristics are improved.

In addition, the light emitting element 240 is supported by a heat transfer member 210 such as a metal, which is thicker than the copper foil, so that the reliability is remarkably improved and there is no need to reinforce the rigidity with the transparent resin, thereby widening the selection range of the resin layer material, .

The insulating layer 220 and the adhesive 295 may be formed together to greatly improve the heat dissipation characteristics. For example, the conductive layer 230 made of a copper foil having a thickness of 18 micrometers and the copper foil having a thickness of 125 micrometers When only the polyimide insulating layer 220 is used between the heat transfer members 210, the thickness of the insulating layer 220 is required to be about 20 to 30 micrometers, for example, in view of tolerance and adhesion.

However, in the present embodiment, the insulating layer 220 and the adhesive 295 are provided together to reduce the thickness of the polyimide. The polyimide is thinly coated on the conductive layer 230 made of the copper foil to form the insulating layer 220 ). As a result, the thickness of the insulating layer 220 of polyimide can be realized to be 5 micrometers. At this time, since the polyimide insulating layer 220 having a thickness of 5 micrometers is responsible for the insulation resistance, the adhesive 295 can increase the thermal conductivity.

9, a pressure is applied to the edge of the heat transfer member 210 to form a step. At this time, the insulating layer 220 and the first and second conductive layers 230 are formed in the same step Respectively.

The step may be a method of pressing the heat transfer member 210 or the like, and the step may be bent perpendicularly or warped as shown in the drawing.

Then, the heat transfer member is bent by applying pressure to the heat transfer member 210 to form the cavity, and the insulating layer 220 and the first and second conductive layers 230 are also bent. The cavity may have a curved shape as shown in FIG. 9, or may have an inflection point at the edge as shown in FIG.

10, the light emitting device 240 is mounted on the bottom surface of the cavity. The light emitting device 240 is bonded to the first and second conductive layers 230 and the wires 250. At this time, the electrode pad 255 may be formed on the first and second conductive layers 230 to which the wire 250 is bonded.

In manufacturing the light emitting device package described above, the insulating layer, the conductive layer, and the like may be stacked on the heat transfer member, and then separated into the respective light emitting device package units. 12 is a partially enlarged view of the light emitting device package array of FIG. 11, and FIG. 13 is a cross-sectional view of the light emitting device package array of FIG. Sectional view in the direction " B ".

 In FIG. 12, the conductive layer 230 forming the cavity is shown, and a heat transfer member (not shown) may be directly exposed in a partial region C of the bottom surface of the cavity.

13, the heat transfer member 210 is exposed at the center of the cavity in the sectional view AA 'of FIG. 12. However, in the cross-sectional view of line BB' of FIG. 13, . That is, the heat transfer member 210 is exposed in the short axis direction in the cavity.

14A to 14F are views showing an embodiment of the manufacturing method of the second embodiment of the light emitting device package.

The present embodiment does not use the base substrate 290, unlike the embodiment shown in Fig. The insulating layer 220 may be formed of an adhesive material such as polyimide to fix the insulating layer 220 to the heat transfer member 210 without using the adhesive 295. In another embodiment, 295 can be omitted.

First, as shown in FIG. 14A, a heat transfer member 210 is prepared. As the heat transfer member 210, a material having excellent thermal conductivity may be used. For example, copper (Cu) or aluminum may be used.

Then, as shown in FIG. 14B, the insulating layer 220 and the conductive layer 230 are fixed on the heat transfer member 210.

Then, as shown in Fig. 14C, the conductive layer 230 is patterned. At this time, a part of the conductive layer 230 is removed to expose the insulating layer 220. The exposed region S is formed by the conductive layer 230 as a first conductive layer and a second conductive layer .

The removal process of a part of the conductive layer 230 may cover the mask and selectively remove the conductive layer 230 as shown in FIG. 5 and the like.

Then, as shown in FIG. 14D, pressure is applied to the heat transfer member 210 so as to form a cavity, thereby bending the heat transfer member. At this time, the insulating layer 220 and the first and second conductive layers 230 are also bent. The cavity may have a curved shape as shown in FIG. 14D, or may have an edge at an inflection point.

14E, a reflective layer 235 is formed on the first and second conductive layers 230 and 230. Referring to FIG. The reflective layer 235 is a material for reflecting light emitted from the light emitting device 240 and transmitting the light to the outside of the cavity, and may be coated with silver (Ag) or the like.

14f, pressure is applied to the edge of the heat transfer member 210 to form a step. At this time, the insulating layer 220 and the first and second conductive layers 230 have the same steps . At this time, as shown in the figure, the reflective layer 235 may be patterned in the same step, but the reflective layer 235 may be formed only in the inner region of the cavity.

The step may be a method of pressing the heat transfer member 210 or the like, and the step may be bent perpendicularly or warped as shown in the drawing.

The concrete configuration of the steps described above is the same as that described in Figs. 2 and 3, and the same is true in the following embodiments.

The light emitting device 240 is mounted on the bottom surface of the cavity. The light emitting device 240 is bonded to the first and second conductive layers 230 and the wires 250. At this time, the electrode pad 255 may be formed on the first and second conductive layers 230 to which the wire 250 is bonded. Further, when the circuit substrate is coupled to the above-described stepped region by using a conductive adhesive, the light emitting device package is completed. 14F, a resin layer (not shown) is filled in the cavity to protect the light emitting element 240 and the wire 250, and the same is true in the following embodiments.

In the embodiment shown in FIG. 14F, since the light emitting device 240 is in contact with the heat transfer member 210 through the conductive layer 230 and the insulating layer 220, the heat dissipating effect is lowered compared with the embodiment shown in FIG. . However, as in the embodiment shown in FIG. 1, the circuit board can be disposed in the edge region of the conductive layer 230 above the cavity. In this case, since the package body is not formed using PPA resin, The effect of the emitted heat being transmitted to the heat transfer member 210 is large.

15 and 16 are views showing a third embodiment and a fourth embodiment of the light emitting device package. 15 differs from the embodiment shown in FIG. 14F in that the light emitting device 240 is wire-bonded to the first and second conductive layers 230 by two wires 250, respectively. In the embodiment shown in FIG. 16, the light emitting device 240 is not electrically connected to the conductive layer 230 by wires, and the light emitting device 240 may be directly connected to the conductive layer 230 using the flip- Bonding is possible.

17A and 17B are a plan view and a cross-sectional view of a fifth embodiment of the light emitting device package.

In the present embodiment, a plurality of light emitting devices 240 are disposed in the cavity, and the light emitting devices 240 are bonded to the conductive layers 230 and 250, .

It is to be noted that the heat transfer member can be exposed in the central region C of the cavity. 17B, the light emitting device 240 directly contacts the heat transfer member 210 exposed at the bottom surface of the cavity. The steps of the heat transfer member 210 and the like in the outer region of the cavity are the same as those in the embodiment shown in FIG.

18A and 18B are a plan view and a sectional view of a sixth embodiment of the light emitting device package.

This embodiment is similar to the embodiment shown in Figs. 17A and 17B, but differs in that the heat transfer member 210 is not exposed at the bottom surface of the cavity. That is, the insulating layer 220 and the conductive layer 230 are all disposed on the heat transfer member 210 on the bottom surface of the cavity in which the light emitting device 240 is disposed.

In order to prevent short-circuiting of the current supplied to the light emitting element, the conductive layer 230 is removed in a partial region C of the bottom surface of the cavity. 18B, the insulating layer 220 is left in the region (C), but the insulating layer 220 is also removed, so that the heat transfer member 210 can be exposed.

Hereinafter, the illumination device and the backlight unit will be described as an embodiment of the illumination system in which the above-described light emitting device package is disposed. 19 is an exploded perspective view of an embodiment of a lighting device including a light emitting device package according to embodiments.

The illumination device according to the embodiment includes a light source 600 for projecting light, a housing 400 in which the light source 600 is embedded, a heat dissipation unit 500 for emitting heat of the light source 600, And a holder 700 for coupling the heat dissipating unit 500 to the housing 400.

The housing 400 includes a socket coupling part 410 coupled to an electric socket and a body part 420 connected to the socket coupling part 410 and having a light source 600 embedded therein. The body 420 may have one air flow hole 430 formed therethrough.

A plurality of air flow openings 430 are provided on the body portion 420 of the housing 400. The air flow openings 430 may be formed of one air flow openings or a plurality of flow openings may be radially arranged Various other arrangements are also possible.

The light source 600 includes a plurality of light emitting device packages 650 on a circuit board 610. Here, the circuit board 610 may be inserted into the opening of the housing 400, and may be made of a material having a high thermal conductivity to transmit heat to the heat dissipating unit 500, as described later.

A holder 700 is provided under the light source. The holder 700 may include a frame and another air flow hole. Although not shown, an optical member may be provided under the light source 100 to diffuse, scatter, or converge light projected from the light emitting device package 150 of the light source 100.

The above-described illuminating device includes the light emitting device package or the light emitting device package described above. Heat emitted from the light emitting device can be discharged directly through the heat transfer member. In the outside of the cavity where the light emitting device is mounted, It is possible to prevent the adhesive material and the resin layer from flowing to the inside / outside of the cavity.

20 is a view illustrating a backlight including the light emitting device package according to the embodiments.

The display device 800 according to the present embodiment includes the light source modules 830 and 835, the reflection plate 820 on the bottom cover 810, the light source module 830 disposed on the front of the reflection plate 820, A first prism sheet 850 and a second prism sheet 860 disposed in front of the light guide plate 840 and a second prism sheet 860 disposed between the first prism sheet 850 and the second prism sheet 860. The light guiding plate 840 guides light emitted from the light- A panel 870 disposed in front of the panel 870 and a color filter 880 disposed in the front of the panel 870.

The light source module comprises a light emitting device package 835 on a circuit board 830. Here, the circuit board 830 may be a PCB or the like, and the light emitting device package 835 is as described above.

The bottom cover 810 may house the components in the display device 800. The reflection plate 820 may be formed as a separate component as shown in the drawing or may be formed on the rear surface of the light guide plate 840, It is also possible that the bottom cover 810 is coated with a material having a high reflectivity.

Here, the reflection plate 820 can be made of a material having a high reflectance and can be used in an ultra-thin shape, and polyethylene terephthalate (PET) can be used.

The light guide plate 840 scatters light emitted from the light emitting device package module so that the light is uniformly distributed over the entire screen area of the LCD. Accordingly, the light guide plate 840 is made of a material having a good refractive index and transmittance. The light guide plate 840 may be formed of polymethyl methacrylate (PMMA), polycarbonate (PC), or polyethylene (PE).

In addition, the light guide plate 840 may be omitted, and the light reflected by the reflection plate 820 may be an air guide type in which the light directly propagates in the panel direction.

The first prism sheet 850 is formed on one side of the support film with a transparent and elastic polymeric material, and the polymer may have a prism layer in which a plurality of steric structures are repeatedly formed. As shown in the drawings, the plurality of patterns may be repeatedly provided with a stripe pattern.

In the second prism sheet 860, the edges and the valleys on one surface of the support film may be perpendicular to the edges and the valleys on one surface of the support film in the first prism sheet 850. This is to disperse the light transmitted from the light source module and the reflection sheet evenly in all directions of the panel 870.

Although not shown, a protective sheet may be provided on each of the prism sheets. A protective layer including light diffusing particles and a binder may be provided on both sides of the support film.

The prism layer may be made of a polymer material selected from the group consisting of polyurethane, styrene butadiene copolymer, polyacrylate, polymethacrylate, polymethyl methacrylate, polyethylene terephthalate elastomer, polyisoprene, polysilicon .

Although not shown, a diffusion sheet may be disposed between the light guide plate 840 and the first prism sheet 850. The diffusion sheet may be made of polyester and polycarbonate-based materials, and the light incidence angle may be maximized by refracting and scattering light incident from the backlight unit.

The diffusion sheet includes a support layer including a light diffusing agent and a first layer and a second layer which are formed on a light exit surface (first prism sheet direction) and a light incident surface (a direction of a reflection sheet) .

Wherein the support layer comprises 0.1 to 10 parts by weight of a siloxane-based light-diffusing agent having an average particle diameter of 1 to 10 micrometers based on 100 parts by weight of a resin in which a methacrylic acid-styrene copolymer and a methyl methacrylate-styrene copolymer are mixed, And 0.1 to 10 parts by weight of an acrylic light-diffusing agent having an average particle diameter of 1 to 10 micrometers.

The first layer and the second layer may contain 0.01 to 1 part by weight of an ultraviolet absorber and 0.001 to 10 parts by weight of an antistatic agent per 100 parts by weight of the methyl methacrylate-styrene copolymer resin.

In the diffusion sheet, the thickness of the supporting layer may be 100 to 10000 micrometers, and the thickness of each layer may be 10 to 1000 micrometers.

In this embodiment, the diffusion sheet, the first prism sheet 850 and the second prism sheet 860 form an optical sheet, which may be made of other combinations, for example, a microlens array, A combination of a lens array or a combination of a prism sheet and a microlens array, or the like.

A liquid crystal display (LCD) panel may be disposed on the panel 870. In addition to the liquid crystal display panel 860, other types of display devices requiring a light source may be provided.

In the panel 870, the liquid crystal is positioned between the glass bodies, and the polarizing plate is placed on both glass bodies to utilize the polarization of light. Here, the liquid crystal has an intermediate property between a liquid and a solid, and liquid crystals, which are organic molecules having fluidity like a liquid, are regularly arranged like crystals. The liquid crystal has a structure in which the molecular arrangement is changed by an external electric field And displays an image.

A liquid crystal display panel used in a display device is an active matrix type, and a transistor is used as a switch for controlling a voltage supplied to each pixel.

A color filter 880 is provided on the front surface of the panel 870 so that light projected from the panel 870 transmits only red, green, and blue light for each pixel.

The backlight unit may include the light emitting device package or the light emitting device package described above. The heat emitted from the light emitting device may be directly discharged through the heat transfer member. In a cavity outside the cavity, It is possible to prevent the adhesive material and the resin layer from flowing to the inside / outside of the cavity.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It will be understood that various modifications and applications are possible. For example, each component specifically shown in the embodiments can be modified and implemented. It is to be understood that all changes and modifications that come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

100: substrate 110, 295: adhesive layer, adhesive
210: heat transfer member 220: insulating layer
230: (first and second) conductive layers 235:
240: light emitting element 255: electrode pad
250: wire 270: circuit board
280: conductive adhesive 290: base substrate
300: mask 400: housing
500: heat dissipating unit 600: light source
700: Holder 800: Display device
810: bottom cover 820: reflector
830: circuit board module 840: light guide plate
850, 860: first and second prism sheets 870:
880: Color filter

Claims (12)

delete delete Board;
A heat transfer member disposed on the substrate and constituting a cavity;
An insulating layer disposed on the heat transfer member at a portion of the bottom surface of the cavity, a side wall, and an outer region of the cavity;
A first conductive layer and a second conductive layer which are in contact with the heat transfer member with the insulating layer interposed therebetween and are electrically isolated from each other;
A circuit board disposed on the heat transfer member, the first conductive layer, and the second conductive layer in an outer region of the cavity and electrically connected to the first conductive layer and the second conductive layer; And
And a light emitting element that is in direct contact with the heat transfer member on the bottom surface of the cavity and is electrically connected to the first conductive layer and the second conductive layer,
In the outer region of the cavity, the heat transfer member is formed with a step,
Wherein the stepped portion of the heat transfer member includes a first end of the upper portion of the heat transfer member and a second end of the lower portion and a connection end between the first end and the second end,
Wherein the heat transfer member has a predetermined thickness at the bottom and side walls of the cavity, the first and second ends of the step and the connecting end,
Wherein an upper surface of the circuit board is higher than an upper surface of the first conductive layer and the second conductive layer,
Wherein the heat transfer member is in direct contact with the substrate through the adhesive layer with the substrate at a lower portion of the cavity, and is exposed and spaced apart from the circuit board at an outer region of the cavity. The method of claim 3,
Wherein the first conductive layer and the second conductive layer are each formed with a step at a portion corresponding to an outer region of the cavity and the heat transfer member and the insulating layer have the same steps as the first conductive layer and the second conductive layer Wherein the light emitting device package has a stepped portion. The method according to claim 3 or 4,
Wherein the heat transfer member is pressed. The method according to claim 3 or 4,
And the second end of the lower portion is disposed in a region outside the first end of the upper portion in the step portion of the heat transfer member. The method according to claim 3 or 4,
Further comprising a resin layer filled in the cavity and including a phosphor and surrounding the light emitting element, wherein an edge of the resin layer is formed to be equal to or lower than a top end of the cavity. delete delete delete delete delete

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