KR101538432B1 - Light emitting device and light emitting module having the same - Google Patents

Light emitting device and light emitting module having the same Download PDF

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Publication number
KR101538432B1
KR101538432B1 KR1020080095405A KR20080095405A KR101538432B1 KR 101538432 B1 KR101538432 B1 KR 101538432B1 KR 1020080095405 A KR1020080095405 A KR 1020080095405A KR 20080095405 A KR20080095405 A KR 20080095405A KR 101538432 B1 KR101538432 B1 KR 101538432B1
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KR
South Korea
Prior art keywords
light emitting
lead frame
housing
circuit board
adjacent
Prior art date
Application number
KR1020080095405A
Other languages
Korean (ko)
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KR20100038250A (en
Inventor
장미연
한정아
최승리
Original Assignee
서울반도체 주식회사
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Priority to KR1020080095405A priority Critical patent/KR101538432B1/en
Publication of KR20100038250A publication Critical patent/KR20100038250A/en
Application granted granted Critical
Publication of KR101538432B1 publication Critical patent/KR101538432B1/en

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/42—Wire connectors; Manufacturing methods related thereto
    • H01L2224/47—Structure, shape, material or disposition of the wire connectors after the connecting process
    • H01L2224/48—Structure, shape, material or disposition of the wire connectors after the connecting process of an individual wire connector
    • H01L2224/4805—Shape
    • H01L2224/4809—Loop shape
    • H01L2224/48091—Arched
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/01—Means for bonding being attached to, or being formed on, the surface to be connected, e.g. chip-to-package, die-attach, "first-level" interconnects; Manufacturing methods related thereto
    • H01L2224/42—Wire connectors; Manufacturing methods related thereto
    • H01L2224/47—Structure, shape, material or disposition of the wire connectors after the connecting process
    • H01L2224/48—Structure, shape, material or disposition of the wire connectors after the connecting process of an individual wire connector
    • H01L2224/481—Disposition
    • H01L2224/48151—Connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive
    • H01L2224/48221—Connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked
    • H01L2224/48245—Connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked the item being metallic
    • H01L2224/48247—Connecting between a semiconductor or solid-state body and an item not being a semiconductor or solid-state body, e.g. chip-to-substrate, chip-to-passive the body and the item being stacked the item being metallic connecting the wire to a bond pad of the item

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  • Engineering & Computer Science (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Manufacturing & Machinery (AREA)
  • Computer Hardware Design (AREA)
  • Power Engineering (AREA)
  • Led Device Packages (AREA)

Abstract

A puzzle type light emitting device capable of realizing various lengths and a light emitting module having the same are disclosed. The light emitting device includes a lead frame, a light emitting chip mounted on the lead frame to generate light, a housing enclosing the lead frame, and an opening for exposing a part of the lead frame on which the light emitting chip is mounted. A groove is formed in the first side of the housing for engagement with the adjacent light emitting element and a second side opposite to the first side is formed with a projection for engagement with the adjacent light emitting element. The lead frame includes a terminal portion formed to be exposed to the third side of the housing perpendicular to the first side of the housing for connection with an external circuit board. Accordingly, packages having various lengths can be realized according to the size of the backlight assembly by combining light emitting elements using grooves and projections formed on both sides of the light emitting element.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a light emitting device,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light emitting device and a light emitting module having the same, and more particularly, to a puzzle type light emitting device capable of realizing various lengths and a light emitting module having the same.

In general, light emitting diodes (LEDs) have many merits such as high luminous efficiency, long life, low power consumption, and being environmentally friendly, and the technology field of using them is continuously increasing.

In recent years, a light emitting diode has been used as a light source in a display device such as a liquid crystal display device that displays an image using light supplied from a separate backlight assembly. Particularly, a backlight assembly applied to a small-sized product such as a mobile communication terminal or a notebook computer has a structure in which a light emitting module including one or more light emitting diodes is disposed on a side surface of a light guide plate. At this time, the light emitting module disposed on the side of the light guide plate has a structure in which one or more side view light emitting diodes are arranged in a line on a printed circuit board at regular intervals, and the light emitting diode is fixed to the printed circuit board .

However, due to the use of a solder cream during the soldering process of the LED, the light emitting diode is twisted during the reflow process or the gap between the light emitting diode and the LGP is generated, There is a difficult problem.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and it is an object of the present invention to provide a light emitting device capable of uniformly maintaining an array of light emitting devices mounted on a circuit board,

Further, the present invention provides a light emitting module having the above-mentioned light emitting element.

According to an aspect of the present invention, there is provided a light emitting device including: a lead frame; a light emitting chip mounted on the lead frame to generate light; and an opening for enclosing the lead frame and exposing a part of the lead frame on which the light emitting chip is mounted And a housing. A groove is formed in a first side of the housing for coupling with an adjacent light emitting element and a second side of the housing opposite to the first side is formed with a projection for coupling with an adjacent light emitting element.

The lead frame includes a terminal portion formed to be exposed to a third side of the housing perpendicular to the first side of the housing for connection with an external circuit board. The width of the first side portion may be smaller than the width of the third side portion.

A light emitting module according to an aspect of the present invention includes a circuit board and a plurality of light emitting elements coupled to the circuit board in series.

The light emitting device includes a lead frame, a light emitting chip mounted on the lead frame to generate light, and a housing having the lead frame enclosed therein and having an opening for exposing a part of the lead frame on which the light emitting chip is mounted do. A groove is formed in a first side of the housing for coupling with an adjacent light emitting element and a second side of the housing opposite to the first side is formed with a projection for coupling with an adjacent light emitting element.

The lead frame includes a terminal portion configured to be exposed to a third side of the housing perpendicular to the first side of the housing for electrical connection with the circuit board.

The circuit board may include a pad portion electrically connected to the terminal portion and a conductive wire for transmitting an electric signal to the pad portion.

Wherein the terminal portion includes a first lead terminal adjacent to the first side portion and a second lead terminal adjacent to the second side portion, wherein the pad portion has a first lead terminal and a second lead terminal different from any one of the two light- And may be formed to be connected to one of the second lead terminals in common.

Wherein the light emitting module is disposed between the adjacent light emitting elements and includes a coupling protrusion coupled to the groove of the light emitting element disposed at one side and a coupling groove coupled to the projection of the light emitting element disposed at the other side, Member. ≪ / RTI >

According to such a light emitting device, packages having various lengths can be implemented according to the size of the backlight assembly by adjusting the length of the package by combining light emitting elements using grooves and projections formed on both sides of the light emitting device. Further, the interval and arrangement between the light guide plate and the light emitting elements can be uniformly maintained, and the light emitting efficiency of the light emitting module can be maintained constant. In addition, by forming the pad portion pattern of the circuit board one by one for each two light emitting elements, it is possible to simplify the pattern formation of the circuit board. Meanwhile, the light emitting module of the present invention can be used by controlling a desired length even for an illumination existing in a line form.

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 of the present invention when taken in conjunction with the accompanying drawings, It will be possible. The present invention is capable of various modifications and various forms, and specific embodiments are illustrated in the drawings and described in detail in the text. It should be understood, however, that the invention is not intended to be limited to the particular forms disclosed, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the terms "comprising" or "having ", and the like, are intended to specify the presence of stated features, integers, steps, operations, elements, parts, or combinations thereof, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, parts, or combinations thereof. The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings.

FIG. 1 is an exploded perspective view illustrating a light emitting module according to an embodiment of the present invention, and FIG. 2 is a plan view showing a coupling relationship of light emitting devices shown in FIG.

Referring to FIGS. 1 and 2, a light emitting module 100 according to an embodiment of the present invention includes a circuit board 200 and light emitting devices 300.

The circuit board 200 fixes the light emitting elements 300 and applies power to the light emitting elements 300. The circuit board 200 may be formed of, for example, a printed circuit board (PCB), a flexible printed circuit board (FPCB), a metal core printed circuit board (MCPCB) . The circuit board 200 may include a pad portion 210 electrically connected to the light emitting device 300 and a conductive wire 220 for transmitting an electrical signal to the pad portion 210.

The light emitting devices 300 are coupled to each other and are coupled to the circuit board 200 in a line. Each of the light emitting elements 300 includes a groove 332 formed in the first side portion 330a and a projection 334 formed in the second side portion 330b for coupling with the adjacent light emitting element 300. [ Accordingly, the light emitting elements 300 adjacent to each other can be coupled to each other through the engagement of the groove 332 and the projection 334. [

FIG. 3 is a perspective view illustrating the light emitting device shown in FIG. 1, and FIG. 4 is a cross-sectional view of the light emitting device taken along the line I-I 'of FIG.

3 and 4, a light emitting device 300 according to an exemplary embodiment of the present invention includes a lead frame 310, a light emitting chip 320, and a housing 330. The light emitting chip 320 is mounted on the lead frame 310 to generate light. The housing 330 surrounds and fixes the lead frame 310 and has an opening 336 for exposing a portion of the lead frame 310 on which the light emitting chip 320 is mounted.

The lead frame 310 supplies power to the light emitting chip 320, which is required for light emission of the mounted light emitting chip 320, from the outside. The lead frame 310 may be formed of a metal having excellent electrical conductivity. The lead frame 310 includes a first lead frame portion 312 and a second lead frame portion 314 that are electrically separated from each other.

The light emitting chip 320 is mounted on the upper surface of the first lead frame part 312. The light emitting chip 320 is made of a semiconductor material such as, for example, gallium nitride, arsenic nitride, or phosphorus nitride, and emits light in response to a power source applied through the lead frame 310. The light emitting chip 320 can emit light of various wavelength ranges depending on its use. For example, the light emitting chip 320 emits light of blue, red, yellow, or ultraviolet wavelength band.

The housing 330 covers most of the area of the lead frame 310 while an opening 336 is formed in the upper region of the light emitting chip 320 so that light generated from the light emitting chip 320 can be emitted. The housing 330 is made of an insulating material, and may be formed of, for example, a polyphthalamide (PPA) resin.

The housing 330 includes a first side 330a and a second side 330b opposite the first side 330a. The housing 330 includes a third side portion 330c extending vertically from one end of the first side portion 330a and connected to one end of the second side portion 330b and a third side portion 330c extending from the fourth side portion 330c opposite to the third side portion 330c. (330d). The width of the first side portion 330a and the second side portion 330b of the housing 330 is formed smaller than the width of the third side portion 330c and the fourth side portion 330d. Accordingly, the housing 330 is formed in a substantially rectangular parallelepiped-like shape in which the first side portion 330a and the second side portion 330b are short sides and the third side portion 330c and the fourth side portion 330d are long sides. do.

A groove 332 for coupling with the adjacent light emitting device 300 is formed on the first side portion 330a of the housing 330. Conversely, on the second side portion 330b of the housing 330, a protrusion 334 for coupling with the adjacent light emitting device 300 is formed. The groove 332 formed in the first side portion 330a is formed in substantially the same shape as the protrusion 334 so that the protrusion 334 formed in the adjacent light emitting device 300 can be fitted and fitted. For example, the protrusions 334 may be formed in various shapes such as a quadrangular prism, a triangular prism, a semicircular prism, etc., and the grooves 332 may be formed in a shape corresponding to the shape of the protrusions 334.

The opening 336 formed in the housing 330 may be formed in a funnel shape having an increased area from the inside toward the top in the direction adjacent to the lead frame 310. [ Therefore, the inner wall of the housing 330, in which the opening 336 is formed, is formed as an inclined surface inclined at a constant angle. Thus, by forming the inclined surface on the inner wall of the housing 330, the directivity angle of the light emitting device 300 can be increased.

The light emitting device 300 may further include a conductive wire 322 for electrically connecting the light emitting chip 320 and the second lead frame part 314. The conductive wire 322 applies an electrical signal from the second lead frame 314 to the light emitting chip 320. Meanwhile, the lower surface of the light emitting chip 320 is electrically connected to the first lead frame part 312 through a conductive adhesive or the like. Accordingly, the light emitting chip 320 generates light in response to an electric power source applied to both sides through the lead frame 310 and the conductive wire 322. [ Meanwhile, the light emitting chip 320 may have a structure electrically connected to the first lead frame part 312 through a separate conductive wire.

The light emitting device 300 may further include a sealing member 340 filled in the opening 336 of the housing 330 to cover the light emitting chip 320 and the conductive wire 322. The sealing member 340 is for protecting the light emitting chip 320 and the conductive wire 322 from the external environment, and may be formed of, for example, a transparent epoxy or a silicone resin. Meanwhile, a fluorescent material for converting the wavelength of the light generated from the light emitting chip 320 may be included in the sealing member 340. For example, the sealing member 340 may include any one or more of red, green, and blue phosphors to realize light of a desired color such as white light.

 FIG. 5 is a plan view showing a third side of the light emitting devices coupled to the circuit board in FIG. 1. FIG.

1, 4 and 5, the lead frame 310 includes terminal portions 316, 316 formed to be exposed to the third side portion 330c of the housing 330 for electrical connection with an external circuit board 200, 318).

The terminal portions 316 and 318 include a first lead terminal 316 formed at a position adjacent to the first side portion 330a and a second lead terminal 318 formed at a position adjacent to the second side portion 330b. For example, the first lead terminal 316 is electrically connected to the second lead frame portion 314 shown in FIG. 4, and the second lead terminal 318 is electrically connected to the first lead frame portion 312 Respectively.

The first lead terminal 316 and the second lead terminal 318 exposed in the third side portion 330c of the housing 330 are electrically connected to the pad portion 210 formed on the circuit board 200 through the soldering process do. The pad 210 formed on the circuit board 200 may include a first lead terminal 316 and a second lead terminal 318 so as to be individually connected to the first lead terminal 316 and the second lead terminal 318, As shown in FIG. Therefore, an electric signal applied from the external power supply through the circuit board 200 is transmitted to the first lead terminal 316 and the second lead terminal 318 via the pad portion 210.

Meanwhile, the pad unit 210 may be patterned to be used commonly for two light emitting devices 300. That is, the pad unit 210 is connected to one of the first lead terminals 316 and the second lead terminal 318 of two adjacent light emitting devices 300 in common, Or the like. By forming the pad portion 210 in this way, the pattern design of the circuit board 200 can be simplified.

6 is a plan view of a light emitting module according to another embodiment of the present invention. In Fig. 6, the remaining configuration except for the connecting member is the same as that shown in Fig. 1, so that the same reference numerals are used for the same components, and redundant detailed description related thereto will be omitted.

Referring to FIG. 6, the light emitting module 100 according to another embodiment of the present invention may further include a connection member 400 disposed between the adjacent light emitting devices 300.

The connection member 400 includes a coupling protrusion 410 coupled to the groove 332 of the light emitting device 300 disposed at one side and a coupling groove 420 coupled to the protrusion 334 of the light emitting device 300 disposed at the other side ). The coupling protrusion 410 formed on one side of the coupling member 400 is formed to have substantially the same shape as the groove 332 so as to be fitted into the groove 332 formed in the adjacent light emitting device 300, The grooves 420 are formed to have substantially the same shape as the protrusions 334 so as to be fitted and engaged with the protrusions 334 formed in the adjacent light emitting device 300. For example, the coupling protrusions 410 and the coupling grooves 420 may be formed in various shapes such as a square pillar, a triangular pillar, a semicircular pillar, and the like. In this manner, the length of the light emitting module can be freely controlled by arranging the connecting members 400 of various sizes between the light emitting elements 300.

As described above, by adjusting the lengths of the packages by combining the light emitting devices 330 using the grooves 332 and the protrusions 334 formed on both sides of the light emitting device 330, various sizes of the backlight assembly Length package can be implemented. Further, the interval and arrangement between the light guide plate and the light emitting devices 330 can be uniformly maintained, and the light emitting efficiency of the light emitting module can be maintained constant. In addition, pattern formation of the circuit board 200 can be simplified by forming the pattern of the pad portions 210 of the circuit board 200 in common for two light emitting elements 330 one by one. Meanwhile, the light emitting module 100 of the present invention can be used by controlling a desired length even for an illumination existing in a line form.

While the present invention has been described in connection with what is presently considered to be practical and exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

1 is an exploded perspective view illustrating a light emitting module according to an exemplary embodiment of the present invention.

2 is a plan view showing a coupling relationship of the light emitting devices shown in FIG.

FIG. 3 is a perspective view showing the light emitting device shown in FIG. 1 in detail.

4 is a cross-sectional view of the light emitting device taken along the line I-I 'in Fig.

 FIG. 5 is a plan view showing a third side of the light emitting devices coupled to the circuit board in FIG. 1. FIG.

6 is a plan view of a light emitting module according to another embodiment of the present invention.

Description of the Related Art

100: light emitting module 200: circuit board

210: pad part 300: light emitting element

310: lead frame 316: first lead terminal

318: second lead terminal 320: light emitting chip

330: housing 332: groove

334: projection 336: opening

400: connecting member 410: engaging groove

420: engaging projection

Claims (8)

delete delete delete A circuit board; And A plurality of light emitting devices coupled in series to the circuit board, The light- Lead frame; A light emitting chip mounted on the lead frame to generate light; And And a housing having the lead frame enclosed therein and having an opening for exposing a part of the lead frame on which the light emitting chip is mounted, A groove is formed in a first side of the housing for coupling with an adjacent light emitting element and a second side of the housing opposite to the first side is formed with a projection for coupling with the adjacent light emitting element, Wherein the lead frame includes a terminal portion configured to be exposed to a third side of the housing perpendicular to the first side of the housing for electrical connection with the circuit board, Wherein the circuit board includes a pad portion electrically connected to the terminal portion, The terminal portion includes a first lead terminal adjacent to the first side portion and a second lead terminal adjacent to the second side portion, Wherein the pad portion is formed to be connected in common to any one of the two first light emitting elements adjacent to each other and one second light emitting terminal different from the first light emitting element. delete 5. The method of claim 4, Wherein the circuit board includes a conductive wiring for transmitting an electric signal to the pad portion. delete 5. The method of claim 4, And a coupling member disposed between the light emitting elements adjacent to each other and including a coupling protrusion coupled to the groove of the light emitting element disposed at one side and a coupling groove coupled to the projection of the light emitting element disposed at the other side Emitting module.
KR1020080095405A 2008-09-29 2008-09-29 Light emitting device and light emitting module having the same KR101538432B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
KR1020080095405A KR101538432B1 (en) 2008-09-29 2008-09-29 Light emitting device and light emitting module having the same

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
KR1020080095405A KR101538432B1 (en) 2008-09-29 2008-09-29 Light emitting device and light emitting module having the same

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KR20100038250A KR20100038250A (en) 2010-04-14
KR101538432B1 true KR101538432B1 (en) 2015-07-22

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101146918B1 (en) * 2010-11-03 2012-05-23 금호전기주식회사 Prefabricated led module

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR200191137Y1 (en) * 2000-03-14 2000-08-16 조순애 Fold-up led holder
KR20080040367A (en) * 2006-11-03 2008-05-08 (주)루멘스 Light emitting diode package

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR200191137Y1 (en) * 2000-03-14 2000-08-16 조순애 Fold-up led holder
KR20080040367A (en) * 2006-11-03 2008-05-08 (주)루멘스 Light emitting diode package

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