KR20130027274A

KR20130027274A - Light emitting device

Info

Publication number: KR20130027274A
Application number: KR1020110090759A
Authority: KR
Inventors: 오진민
Original assignee: 엘지이노텍 주식회사
Priority date: 2011-09-07
Filing date: 2011-09-07
Publication date: 2013-03-15

Abstract

PURPOSE: A light emitting device is provided to protect light emitting chips by connecting a protection device to a connection circuit of a first light emitting chip and a second light emitting chip in parallel. CONSTITUTION: A body(10) has a first cavity(60). A first lead frame(21) has a second cavity with a lower depth than the bottom of the first cavity. A second lead frame(31) has a third cavity with a lower depth than the bottom of the first cavity. A first light emitting chip(71) is arranged in the second cavity. A second light emitting chip(72) is arranged in the third cavity. A protection device(78) is arranged in a separation part between the first cavity and the second cavity.

Description

[0001] LIGHT EMITTING DEVICE [0002]

The present invention relates to a light emitting device.

A light emitting device, such as a light emitting device, is a kind of semiconductor device that converts electrical energy into light, and has been spotlighted as a next-generation light source by replacing a conventional fluorescent lamp and an incandescent lamp.

Since the light emitting diode generates light by using a semiconductor device, the light emitting diode consumes very low power compared to a fluorescent lamp that generates light by heating tungsten to generate light by incandescent lamps or by colliding ultraviolet rays generated through high-voltage discharges with phosphors .

In addition, since the light emitting diode generates light using the potential gap of the semiconductor device, it has a longer lifetime, faster response characteristics, and an environment-friendly characteristic as compared with the conventional light source.

Accordingly, much research has been conducted to replace an existing light source with a light emitting diode, and a light emitting diode is increasingly used as a light source for various lamps used for indoor and outdoor use, lighting devices such as a liquid crystal display, an electric signboard, and a streetlight.

The embodiment provides a light emitting device having a new structure.

The embodiment provides a light emitting device in which a protective element is disposed in a body between a cavity of a first lead frame and a cavity of a second lead frame.

The light emitting device according to the embodiment, the body having a first cavity (cavity); A first lead frame disposed in a first region of the first cavity and having a second cavity having a lower depth than a bottom of the first cavity; A second lead frame disposed in a second region of the first cavity and having a third cavity of a lower depth than a bottom of the first cavity; A first light emitting chip disposed in the second cavity; A second light emitting chip disposed in the third cavity; And a protection element disposed in a separation between the first cavity and the second cavity of an area of the body below the bottom of the first cavity.

The embodiment can improve the light extraction efficiency of the light emitting device.

The embodiment can improve the appearance of the light emitting device by disposing the protection device in the body between the cavities.

The embodiment can improve the reliability of the light emitting device and the light unit having the light emitting device.

1 is a perspective view of a light emitting device according to a first embodiment.
2 is a side cross-sectional view of the light emitting device of FIG. 1.
3 is a side cross-sectional view of a light emitting device according to a second embodiment.
4 is a side cross-sectional view of a light emitting device according to a third embodiment.
5 is a perspective view of a display device having a light emitting device according to an embodiment.
6 is a side cross-sectional view showing another example of a display device having a light emitting element according to the embodiment.
7 is a perspective view of a lighting device having a light emitting device according to the embodiment.

BRIEF DESCRIPTION OF THE DRAWINGS The above and other features and advantages of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which: FIG. In the drawings, dimensions are exaggerated, omitted, or schematically illustrated for convenience and clarity of illustration. In addition, the size of each component does not necessarily reflect the actual size. The same reference numerals denote the same elements throughout the description of the drawings.

Hereinafter, a light emitting device according to an embodiment will be described with reference to the accompanying drawings.

1 is a perspective view of a light emitting device according to an embodiment, and FIG. 2 is a side cross-sectional view of the light emitting device of FIG. 1.

1 and 2, the light emitting device 100 includes a body 10 having a first cavity 60, a first lead frame 21 having a second cavity 25, and a third cavity 35. It includes a second lead frame 31 having a, the connecting portion 46, the light emitting chips (71, 72), the protection element 78, the wires (73 to 76, 79) and the molding member (81).

The body 10 may be formed of at least one of a resin material such as polyphthalamide (PPA), silicon (Si), metal, photo sensitive glass (PSG), sapphire (Al ₂ O ₃ ), and printed circuit board (PCB). Can be formed. The body 10 may be made of, for example, a resin material such as polyphthalamide (PPA).

The body 10 may be formed of a conductive material. When the body 10 is formed of a material having electrical conductivity, an insulating film (not shown) is further formed on the surface of the body 10 such that the body 10 is formed of the second cavity 25, the third cavity 35, It may be configured to prevent electrical short with the connection 46.

The top shape of the body 10 may have various shapes such as triangle, square, polygon, and round shape according to the use and design of the light emitting device 100. The first lead frame 21 and the second lead frame 31 may be disposed on the bottom of the body 10 and mounted on the substrate in a direct type, and may be disposed on the side of the body 10 in an edge type. It may be mounted on a substrate, but is not limited thereto.

The body 10 is open at the top and has a first cavity 60 consisting of side and bottom. The first cavity 60 may include a cup structure or a recess structure concave from the upper surface 15 of the body 10, but is not limited thereto. Sides 61 to 68 of the first cavity 60 may be perpendicular to or inclined with respect to the floor.

The shape of the first cavity 60 viewed from above may be circular, elliptical, or polygonal (eg, rectangular). The body 10 may include a plurality of side surfaces 11 to 14, and at least one of the plurality of side surfaces 11 to 14 may be disposed perpendicularly or inclined with respect to the bottom surface of the body 10. The body 10 describes first to fourth side surfaces 11 to 14 as an example, and the first side surface 11 and the second side surface 12 are opposite to each other, and the third side surface 13 and The fourth side surfaces 14 are opposite sides. The width or length of the first side surface 11 and the second side surface 12 may be different from the width or length of the third side surface 13 and the fourth side surface 14, for example, from the first side surface 11. The length of the second side surface 12 (ie, the long side length) may be longer than that of the third side surface 13 and the fourth side surface 14 (ie, the short side length). Here, the length direction of the first and second side surfaces 11 and 12 may be a direction passing through the centers of the second and third cavities 25 and 35.

The first lead frame 21 is disposed in a first region of the first cavity 60, and a part of the first lead frame 21 is disposed at the bottom 16 of the first cavity 60 and the first cavity 60 at a central portion thereof. The concave second cavity 25 is arranged to have a depth lower than the bottom of). The second cavity 25 includes a concave shape, for example, a cup structure or a recess shape, in the direction of the lower surface of the body 10 from the upper surface of the first lead frame 21.

Side surfaces of the second cavity 25 may be inclined or vertically bent from the bottom of the second cavity 25. Two opposite sides of the side surface of the second cavity 25 may be inclined at the same angle or inclined at different angles.

The second lead frame 31 is disposed in a second area spaced apart from the first area of the first cavity 60, and a part of the second lead frame 31 is disposed on the bottom 16 of the first cavity 60, and a central portion thereof. The recessed third cavity 35 is formed to have a lower depth than the bottom of the first cavity 60. The third cavity 35 includes a concave shape, for example, a cup structure or a recess shape, in the direction of the lower surface of the body 10 from the upper surface of the second lead frame 131. The side surface of the third cavity 35 may be bent or vertically bent from the bottom of the third cavity 35. Two opposing side surfaces of the third cavity 35 may be inclined at the same angle or inclined at different angles.

The second cavity 25 and the third cavity 35 may be formed in the same shape, but is not limited thereto.

The lower surface of the first lead frame 21 and the lower surface of the second lead frame 31 may be exposed to the lower surface of the body 10 or disposed on the same plane as the lower surface of the body 10.

The first lead part 23 of the first lead frame 21 may be disposed on the bottom surface of the body 10 and protrude to the third side surface 13 of the body 10. The second lead part 33 of the second lead frame 31 may be disposed on the bottom surface of the body 10 and protrude to the fourth side surface 14 of the body 10.

The first lead frame 21 and the second lead frame 31 are made of a metal material, for example, titanium (Ti), copper (Cu), nickel (Ni), gold (Au), chromium (Cr), and tantalum. It may include at least one of aluminum (Ta), platinum (Pt), tin (Sn), silver (Ag), and phosphorus (P), and may be formed of a single metal layer or a multilayer metal layer. The first and second lead frames 21 and 31 may have the same thickness, but the thickness of the first and second lead frames 21 and 31 is not limited thereto.

The bottom shape of the second cavity 25 and the third cavity 35 may be a circle or ellipse having a rectangle, a regular rectangle or a curved surface.

A connection part 46 is disposed at the bottom 16 of the first cavity 60, and the connection part 46 is a separation part 19 between the second cavity 25 and the third cavity 35. And a first side of the body 10. The connection part 46 is disposed between the first lead frame 21 and the second lead frame 31 to serve as an intermediate connection terminal.

The first light emitting chip 71 is disposed in the second cavity 25 of the first lead frame 21, and the second light emitting chip 71 is disposed in the third cavity 35 of the second lead frame 31. 72 may be disposed.

The light emitting chips 71 and 72 may selectively emit light in a range of visible light band to ultraviolet band, and for example, may be selected from red LED chips, blue LED chips, green LED chips, and yellow green LED chips. have. The light emitting chips 71 and 72 include compound semiconductor light emitting devices of Group III to Group V elements.

The first light emitting chip 72 is connected to the first lead frame 21 disposed on the bottom 16 of the first cavity 60 through a first wire 73 and the second wire 74. It is connected to the connecting portion 46. The second light emitting chip 73 is connected to the first connector 46 by a third wire 75, and is disposed on the bottom 16 of the first cavity 60 by a fourth wire 76. It is connected to the two-lead frame 31. The connection part 46 electrically connects the first light emitting chip 71 and the second light emitting chip 72.

A molding member 81 is disposed in at least one of the first cavity 60, the second cavity 25, and the third cavity 35 of the body 10, and the molding member 81 is formed of silicon or It includes a light-transmissive resin layer such as epoxy, and may be formed in a single layer or multiple layers. The molding member 81 may include a phosphor for changing a wavelength of light emitted on the light emitting chips 71 and 72, and the phosphor excites a part of light emitted from the light emitting chips 71 and 72. To emit light of different wavelengths. The phosphor may be selectively formed from YAG, TAG, Silicate, Nitride, and Oxy-nitride based materials. The phosphor may include at least one of a red phosphor, a yellow phosphor, and a green phosphor, but the present invention is not limited thereto. The surface of the molding member 81 may be formed in a flat shape, a concave shape, a convex shape, or the like, but is not limited thereto.

A lens may be further formed on the upper portion of the body 10, and the lens may include a concave or / and convex lens structure to adjust light distribution of light emitted from the light emitting device 100. Can be.

The protection element 78 may be disposed below a portion 22 of the first lead frame 21 of the body 10. The protection element 78 is disposed in the separation unit 19 between the second cavity 25 and the third cavity 35 in the area under the bottom 16 of the first cavity 60.

The protection element 78 may be disposed closer to the lower surface than the upper surface 15 of the body 10, but is not limited thereto.

Here, the bottom surface of the portion 22 of the first lead frame 21 and the bottom surface of the portion 32 of the second lead frame 31 are bottoms of the second cavity 25 and the third cavity 35. Placed higher than that.

The protection element 78 is mounted on a lower surface of the portion 22 of the first lead frame 21 and connected to a fifth wire 79 under the portion 32 of the second lead frame 31. . Since the protection element 78 is disposed in the body 10, light loss by the protection element 78 on the light emitting device 100 may be reduced.

The protection element 78 may be implemented as a thyristor, a zener diode, or a transient voltage suppression (TVS), and the zener diode protects the light emitting chip from electro static discharge (ESD).

The protection element 78 may be connected to the connection circuits of the first light emitting chip 71 and the second light emitting chip 72 in parallel, thereby protecting the light emitting chips 71 and 72.

3 is a view showing a light emitting device according to a second embodiment.

Referring to FIG. 3, the light emitting device includes a protective element 78 mounted on a lower surface of a portion 32 of the second lead frame 31 and connected to the first lead frame 21 and the fifth wire 79. to be. The protection device 78 may be protected by the separation unit 19 of the body 10, and disposed in the body 10 to reduce light loss of the light emitting device.

4 is a view showing a light emitting device according to a third embodiment.

Referring to FIG. 4, the light emitting device includes a first lead frame 21 in which a protective element 78 is disposed at a separation portion 19 of the body 10 between the second cavity 25 and the third cavity 35. And a portion 22 of the second lead frame 31 and a portion 32 of the second lead frame 31. That is, the protection element 78 is bonded in a flip manner to a portion 22 of the first lead frame 21 and a portion 32 of the second lead frame 31.

The light emitting device according to the embodiment may be applied to the light unit. The light unit includes a structure in which a plurality of light emitting elements are arranged, and includes a display device as shown in FIGS. 5 and 6 and a lighting device as shown in FIG. Can be applied to the unit.

5 is an exploded perspective view of a display device according to an exemplary embodiment.

Referring to FIG. 5, the display device 1000 includes a light guide plate 1041, a light emitting module 1031 providing light to the light guide plate 1041, a reflective member 1022 under the light guide plate 1041, and A bottom cover 1011 that houses an optical sheet 1051 on the light guide plate 1041, a display panel 1061 on the optical sheet 1051, the light guide plate 1041, a light emitting module 1031, and a reflective member 1022. ), But is not limited thereto.

The bottom cover 1011, the reflective sheet 1022, the light guide plate 1041, and the optical sheet 1051 can be defined as a light unit 1050.

The light guide plate 1041 serves to diffuse the light provided from the light emitting module 1031 to make a surface light source. The light guide plate 1041 is made of a transparent material, for example, acrylic resin-based such as polymethyl metaacrylate (PMMA), polyethylene terephthlate (PET), polycarbonate (PC), cycloolefin copolymer (COC), and polyethylene naphthalate (PEN). It may include one of the resins.

The light emitting module 1031 is disposed on at least one side of the light guide plate 1041 to provide light to at least one side of the light guide plate 1041, and ultimately serves as a light source of the display device.

At least one light emitting module 1031 may be disposed in the bottom cover, and may provide light directly or indirectly at one side of the light guide plate 1041. The light emitting module 1031 may include a substrate 1033 and a light emitting device 100 according to the exemplary embodiment disclosed above, and the light emitting device 100 may be arranged on the substrate 1033 at predetermined intervals. The substrate may be a printed circuit board, but is not limited thereto. In addition, the substrate 1033 may include a metal core PCB (MCPCB, Metal Core PCB), flexible PCB (FPCB, Flexible PCB) and the like, but is not limited thereto. When the light emitting device 100 is mounted on the side surface of the bottom cover 1011 or the heat dissipation plate, the substrate 1033 may be removed. A part of the heat radiation plate may be in contact with the upper surface of the bottom cover 1011. Therefore, heat generated in the light emitting device 100 may be discharged to the bottom cover 1011 via the heat dissipation plate.

The plurality of light emitting devices 100 may be mounted on the substrate 1033 such that an emission surface on which light is emitted is spaced apart from the light guide plate 1041 by a predetermined distance, but is not limited thereto. The light emitting device 100 may directly or indirectly provide light to a light incident portion, which is one side of the light guide plate 1041, but is not limited thereto.

The reflective member 1022 may be disposed under the light guide plate 1041. The reflective member 1022 reflects the light incident on the lower surface of the light guide plate 1041 and supplies the reflected light to the display panel 1061 to improve the brightness of the display panel 1061. The reflective member 1022 may be formed of, for example, PET, PC, or PVC resin, but is not limited thereto. The reflective member 1022 may be an upper surface of the bottom cover 1011, but is not limited thereto.

The bottom cover 1011 may house the light guide plate 1041, the light emitting module 1031, the reflective member 1022, and the like. To this end, the bottom cover 1011 may be provided with a housing portion 1012 having a box-like shape with an opened upper surface, but the present invention is not limited thereto. The bottom cover 1011 may be coupled to a top cover (not shown), but is not limited thereto.

The bottom cover 1011 may be formed of a metal material or a resin material, and may be manufactured using a process such as press molding or extrusion molding. In addition, the bottom cover 1011 may include a metal or a non-metal material having good thermal conductivity, but the present invention is not limited thereto.

The display panel 1061 is, for example, an LCD panel, and includes a first and second substrates of transparent materials facing each other, and a liquid crystal layer interposed between the first and second substrates. A polarizing plate may be attached to at least one surface of the display panel 1061, but the present invention is not limited thereto. The display panel 1061 displays information by transmitting or blocking light provided from the light emitting module 1031. The display device 1000 can be applied to video display devices such as portable terminals, monitors of notebook computers, monitors of laptop computers, and televisions.

The optical sheet 1051 is disposed between the display panel 1061 and the light guide plate 1041 and includes at least one light-transmitting sheet. The optical sheet 1051 may include at least one of a sheet such as a diffusion sheet, a horizontal / vertical prism sheet, a brightness enhanced sheet, and the like. The diffusion sheet diffuses incident light, and the horizontal and / or vertical prism sheet concentrates incident light on the display panel 1061. The brightness enhancing sheet reuses the lost light to improve the brightness I will. A protective sheet may be disposed on the display panel 1061, but the present invention is not limited thereto.

The light guide plate 1041 and the optical sheet 1051 may be included as an optical member on the optical path of the light emitting module 1031, but are not limited thereto.

6 is a view showing a display device having a light emitting device according to an embodiment.

Referring to FIG. 6, the display device 1100 includes a bottom cover 1152, a substrate 1120 on which the light emitting device 100 disclosed above is arranged, an optical member 1154, and a display panel 1155.

The substrate 1120 and the light emitting device 100 may be defined as a light emitting module 1060. The bottom cover 1152, at least one light emitting module 1060, and the optical member 1154 may be defined as a light unit (not shown).

The bottom cover 1152 may include an accommodating part 1153, but is not limited thereto.

The optical member 1154 may include at least one of a lens, a light guide plate, a diffusion sheet, a horizontal and vertical prism sheet, and a brightness enhancement sheet. The light guide plate may be made of a PC material or a poly methy methacrylate (PMMA) material, and the light guide plate may be removed. The diffusion sheet diffuses the incident light, and the horizontal and vertical prism sheets condense the incident light onto the display panel 1155. The brightness enhancing sheet reuses the lost light to improve the brightness .

The optical member 1154 is disposed on the light emitting module 1060, and performs surface light source, diffusion, condensing, etc. of the light emitted from the light emitting module 1060.

7 is a perspective view of a lighting apparatus according to an embodiment.

Referring to FIG. 7, the lighting device 1500 includes a case 1510, a light emitting module 1530 installed in the case 1510, and a connection terminal installed in the case 1510 and receiving power from an external power source. 1520).

The case 1510 may be formed of a material having good heat dissipation, for example, may be formed of a metal material or a resin material.

The light emitting module 1530 may include a substrate 1532 and a light emitting device 100 according to an embodiment mounted on the substrate 1532. The plurality of light emitting devices 100 may be arranged in a matrix form or spaced apart at predetermined intervals.

The substrate 1532 may be a circuit pattern printed on an insulator. For example, a general printed circuit board (PCB), a metal core PCB, a flexible PCB, a ceramic PCB, FR-4 substrates and the like.

In addition, the substrate 1532 may be formed of a material that reflects light efficiently, or a surface may be coated with a color, for example, white or silver, in which the light is efficiently reflected.

At least one light emitting device 100 may be mounted on the substrate 1532. Each of the light emitting devices 100 may include at least one light emitting diode (LED) chip. The LED chip may include a light emitting diode in a visible light band such as red, green, blue, or white, or a UV light emitting diode emitting ultraviolet (UV) light.

The light emitting module 1530 may be disposed to have a combination of various light emitting devices 100 to obtain color and luminance. For example, a white light emitting diode, a red light emitting diode, and a green light emitting diode may be combined to secure high color rendering (CRI).

The connection terminal 1520 may be electrically connected to the light emitting module 1530 to supply power. The connection terminal 1520 is inserted into and coupled to an external power source in a socket manner, but is not limited thereto. For example, the connection terminal 1520 may be formed in a pin shape and inserted into an external power source, or may be connected to the external power source by a wire.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Will be clear to those who have knowledge of. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification, but should be defined by the claims.

60: first cavity 10: body,
21, 31: lead frame 25: second cavity
35: third cavity 46: connecting portion
71: first light emitting chip 72: second light emitting chip
78: protection element

Claims

A body having a first cavity;
A first lead frame disposed in a first region of the first cavity and having a second cavity having a lower depth than a bottom of the first cavity;
A second lead frame disposed in a second region of the first cavity and having a third cavity of a lower depth than a bottom of the first cavity;
A first light emitting chip disposed in the second cavity;
A second light emitting chip disposed in the third cavity; And
And a protective element disposed in a separation portion between the first cavity and the second cavity of an area of the body below the bottom of the first cavity.

The method of claim 1,
The protection device is mounted on a portion of the first lead frame and the light emitting device connected to the second lead frame by a wire.

The method of claim 1,
The protection device is mounted on a portion of the second lead frame and the light emitting device connected to the first lead frame by a wire.

The method of claim 1,
The protection device is a light emitting device mounted under the first lead frame and the second lead frame.

The light emitting device of any one of claims 2 to 4, wherein the lower surface of the first lead frame and the lower surface of the second lead frame are disposed higher than the bottom of the second cavity and the third cavity.

The method of claim 5,
The lower surface of the first lead frame disposed in the second cavity and the second lead frame disposed in the third cavity is disposed on the lower surface of the body.

The method of claim 5,
A connection portion disposed on the bottom of the first cavity and disposed between the second and third cavities and between the first side surface of the body,
The connection part is a light emitting device electrically connected to the first and second light emitting chip.

The method of claim 7, wherein
The first and second light emitting chip is a light emitting device connected to the first lead frame, the second lead frame and the connecting portion by a wire.

The light emitting device of claim 5, further comprising a molding member in at least one of the first, second, and third cavities.