KR20070093716A - LED package and backlight unit using the same - Google Patents

Abstract

The present invention relates to a light emitting diode package and a backlight unit using the same.

Each of the light emitting diode packages includes a plurality of main bodies on which light emitting diodes are mounted; Threaded portions formed on lower sides of the main bodies; And a printed circuit board fastened to the main bodies via the screw unit.

Description

Light emitting diode package and backlight unit using the same {LED Pakage and Back Light Unit using the same}

1 is a view showing a conventional light emitting diode package.

FIG. 2 is a cross-sectional view illustrating the light emitting diode package shown in FIG. 1. FIG.

3 is a perspective view showing a light emitting diode array for a liquid crystal display device;

4 is a perspective view showing a light emitting diode package according to an embodiment of the present invention.

FIG. 5 is a cross-sectional view illustrating the light emitting diode package shown in FIG. 4. FIG.

FIG. 6 is a perspective view illustrating the fastening of the LED package and the metal printed circuit board of FIG. 4. FIG.

7 is a cross-sectional view showing an edge type backlight unit to which the light emitting diode package of the present invention is applied.

8 is a cross-sectional view showing a direct backlight unit to which the light emitting diode package of the present invention is applied.

<Explanation of symbols for main parts of drawing>

10, 110: support 12, 112: heat sink slug

14, 114: reflection cup 16, 116: silicon sub-mount

18, 118: light emitting diode chip 20, 120: plastic lens

22, 122: cathode lead 24, 124: anode lead

26, 126: wire 30, 130, 152, 182: MCPCB

32 soldering 34 thermally conductive paste bonding

100: main body 132: socket portion

140: screw portion 150, 180: LED array

154: LED reflector 156, 164: reflector

158, 174: light guide plate 160, 170: optical sheets

162, 172: liquid crystal display panel

The present invention relates to a light emitting diode package, and more particularly, to a light emitting diode package and a backlight unit using the same.

In general, the liquid crystal display device has a trend that the application range is gradually widened due to the characteristics such as light weight, thin, low power consumption. In accordance with this trend, liquid crystal displays are used in office automation equipment, audio / video equipment, and the like. Such a liquid crystal display device adjusts light transmittance according to signals applied to a plurality of control switches arranged in a matrix to display a desired image on a screen.

Since the liquid crystal display is not a self-luminous display, a separate light source such as a back light is required.

The backlight includes a direct type and an edge type according to the position of the light source. The edge type backlight is provided with a light source at one edge of the liquid crystal display, and irradiates the liquid crystal display panel with light incident from the light source through the light guide plate and the plurality of optical sheets. In the direct type backlight, a plurality of light sources are disposed directly below the liquid crystal display, and light incident from the light sources is irradiated to the liquid crystal display panel through the plurality of optical sheets. Light sources used for the backlight include a cold cathode fluorescent lamp (CCFL) and a light emitting diode (hereinafter referred to as "LED").

However, according to the trend of miniaturization, thinning, and lightening of the backlight unit, LEDs, which are advantageous light sources in terms of power consumption, thickness, weight, and brightness, have been widely used in comparison with cold cathode fluorescent lamps.

Referring to FIG. 1, a conventional LED package 1 includes a support 10 having a central hole, a heat sink slug 12 mounted at a center portion of the support 10, and a cup on an upper surface of the heat sink slug 12. A reflective cup 14 provided in the shape, a silicon sub-mount 16 in which the LED chip 18 is bonded to the reflective cup 14 with a thermally conductive paste, and a direction in which the light generated from the LED chip 18 is desired. And a plastic lens 20 to be irradiated with a cathode, and cathode and anode leads 22 and 24.

The support 10 supports the entire LED package and is manufactured in a circular or polygonal shape.

The heat sink slug 12 is formed of a material having high thermal conductivity such as silver, copper, aluminum, etc. to dissipate heat generated from the LED chip 18.

The reflection cup 14 reflects the light generated by the LED chip 18 and proceeds toward the front side.

The LED chip 18 generates light.

The silicon submount 16 is thermally conductive paste bonded to the LED chip 18 and electrically connected to the LED chip 18. The silicon submount 16 is also electrically connected to the cathode leads and anode leads 22, 24 by wire 26.

The cathode and anode leads 22 and 24 are installed on both sides of the support 10 and electrically connected to the LED chip 18.

The LED package 1 is bonded to a metal coating printed circuit board (hereinafter referred to as "MCPCB", 30) as shown in FIG. Here, the MCPCB 30 is electrically connected to the cathode and anode leads 22 and 24 of the LED chip 18 to drive the LED chip 18 and radiate heat generated from the LED chip 18. Specifically, the heat sink slug 12 of the LED package is adhered onto the MCPCB 30 by a thermally conductive paste junction 34. The cathode and anode leads 22, 24 are then joined to the MCPCB 30 by soldering 32, i.e., soldering.

The plurality of LED packages 1 used in the backlight unit for the liquid crystal display device are bonded to have a constant pitch on the MCPCB 30 as shown in FIG. 3. When a plurality of LED packages are used in this way, when one LED package is defective, the LED package is bonded on the MCPCB 30, and thus it is difficult and impossible to replace one defective LED package. Accordingly, a problem arises in that the entire MCPCB 30 in which the LED packages are mounted is replaced.

Accordingly, an object of the present invention is to provide a light emitting diode package and a backlight unit using the same.

In order to achieve the above object, the light emitting diode package according to the present invention each comprises a plurality of main body on which the light emitting diode is mounted; Threaded portions formed on lower sides of the main bodies; And a printed circuit board fastened to the main bodies via the screw unit.

A lens is provided on the upper side of the main body.

The printed circuit board is a metal printed circuit board.

The main body has a support through the central portion; A heat sink slug mounted to the center portion of the support; A reflection cup installed in a cup shape on an upper surface of the sink slug; A silicon sub-mount in which a light emitting diode chip is thermally conductive paste bonded to the reflective cup; And a cathode and an anode lead electrically connecting the light emitting diode chip and the screw unit.

In one embodiment, a backlight unit includes a liquid crystal display panel; And a plurality of main bodies each having a light emitting diode mounted thereon, a screw unit formed under each of the main bodies, and a printed circuit board fastened to the main units through the screw unit to attach light to the liquid crystal display panel. A light emitting diode package is provided.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to FIGS. 4 to 8.

Referring to FIG. 4, the LED package according to the embodiment of the present invention includes a main body 100 on which the LED chip 118 that generates light is mounted, and a plastic that is installed above the main body 100 to irradiate light in a desired direction. The lens 120 and a screw 140 protruding from the lower side of the main body 100 are provided.

As shown in FIG. 5, the main body 100 of the LED package includes a support 110 having a central portion through which the center portion is perforated, a heat sink slug 112 mounted at a center portion of the support 110, and an upper surface of the heat sink slug 112. A reflective cup 114 provided in a cup shape, a silicon sub-mount 116 in which the LED chip 118 is thermally conductive bonded to the reflective cup 114, and a direction in which the light generated from the LED chip 118 is desired. It consists of a plastic lens 120 to be irradiated with, and cathode and anode leads (122, 124). The LED chip 118 includes a red LED chip generating red light, a green LED chip generating green light, and a blue LED chip generating chuck color light.

The support 110 supports the entire LED package and is manufactured in a circular or polygonal shape.

The heat sink slug 112 is formed of a material having high thermal conductivity such as silver, copper, and aluminum to dissipate heat generated from the LED chip 118.

The reflection cup 114 reflects the light generated by the LED chip 118 and proceeds toward the front side.

The silicon submount 116 is thermally paste bonded to the LED chip 118 and electrically connected to the LED chip 118. In addition, the silicon submount 116 is electrically connected to the cathode lead and the anode lead 122, 124 by a wire 126.

The cathode lead 122 electrically connects the LED chip 118 and the cathode terminal 142 of the threaded portion 140, and the anode lead 124 is an anode terminal 144 of the LED chip 118 and the threaded portion 140. Is electrically connected.

This LED package is fastened by screw and socket coupling on the MCPCB 130 as shown in FIG. In other words, the socket portion 132 is formed inside the MCPCB 130 and the screw portion 140 of the LED package, and the LED portion of the LED package is inserted into the socket portion 132 by inserting the screw portion 140 of the LED package. Is fixed on 130. Here, the MCPCB 130 is electrically connected to the cathode and anode terminals 142 and 144 of the screw 140 of the LED package to drive the LED chip 118. In addition, the MCPCB 130 has a high thermal conductivity metal material such as aluminum coated on the lower side to dissipate heat generated from the LED chip 118.

As such, when the LED package is screwed and screwed into the MCPCB 130, even if one bad LED package occurs, only one LED package needs to be replaced without replacing the whole. Accordingly, the present invention can improve the productivity because the work is made efficiently and can prevent the waste of materials. In addition, when the LED package of the present invention is screwed and the socket fastening in the MCPCB 130, it is possible to improve the reliability by preventing the alignment of the LED array of the conventional junction structure (align).

The LED package mounted on the MCPCB 130 is called an LED array, and the LED array can be applied to both an edge type backlight unit and a direct type backlight unit.

Referring to FIG. 7, the edge type backlight unit of the present invention includes an LED array 150 provided at both sides of the light guide plate 158, and an LED reflector 154 reflecting light from the LED array 150 to the light guide plate 158. The light guide plate 158 includes a reflective plate 156 disposed below the light guide plate 158, and a plurality of optical sheets 160 stacked between the light guide plate 158 and the liquid crystal display panel 162.

The LED array 150 has a LED package for generating light is fastened by screw and socket coupling, that is, a screw fastening method on the MCPCB 152.

The reflector 156 reflects the light emitted from the LED array 150 in the direction of the light guide plate 158.

The light guide plate 158 mixes red, green, and blue light from the LED array 150, and simultaneously converts light incident from the LED array 150 into a surface light source so that the light path is perpendicular to the liquid crystal display panel 162. To convert it. In this case, the light guide plate 158 is generally formed of polymethylmethacrylate (PMMA) having high strength and not easily being deformed or broken and having good transmittance.

The plurality of optical sheets 160 includes a diffusion sheet and a brightness rising sheet. At this time, the diffusion sheet serves to expand the light emitted from the light guide plate 158 and the brightness increasing sheet increases the brightness of the light. Dual brightness enhancement films (DBEF) and brightness enhancement films (BEFs) are mainly used as the brightness increase sheet.

Referring to FIG. 8, the direct type backlight unit of the present invention includes an LED array 180 installed below the light guide plate 174, a reflector plate 164 provided between a main body of the LED package and a plastic lens, a light guide plate 174, and a liquid crystal. A plurality of optical sheets 170 are stacked between the display panel 172.

The LED array 180 has a LED package for generating light is fastened by screw and socket coupling on the MCPCB 182.

The reflective plate 164 is installed between the body of the LED package and the plastic lens to reflect the light emitted from the LED array 180 in the direction of the light guide plate 174.

The light guide plate 174 mixes red, green, and blue light from the LED array 180, and simultaneously converts light incident from the LED array 180 into a surface light source so that the light path is perpendicular to the liquid crystal display panel 172. To convert it. In this case, the light guide plate 174 is generally formed of polymethylmethacrylate (PMMA) having high strength and not easily being deformed or broken and having good transmittance.

The plurality of optical sheets 170 includes a diffusion sheet and a brightness rising sheet. In this case, the diffusion sheet serves to expand the light emitted from the light guide plate 174, and the brightness increasing sheet increases the brightness of the light. Dual brightness enhancement films (DBEF) and brightness enhancement films (BEFs) are mainly used as the brightness increase sheet.

Therefore, the LED package and the backlight unit using the same according to the present invention are easy to replace one LED package by screwing and screwing the LED package on the MCPCB. Accordingly, since the LED package and the backlight unit using the same according to the present invention only need to replace one defective LED when one defective LED is generated, productivity and workability may be improved as compared with the related art.

In addition, the LED package and the backlight unit using the same according to the present invention can improve the reliability by preventing alignment of the LED array in the conventional junction structure.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the technical spirit of the present invention. 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.

Claims (12)

A plurality of main bodies each having a light emitting diode mounted thereon; Threaded portions formed on lower sides of the main bodies; And A light emitting diode package comprising a printed circuit board fastened to the main body through the screw portion. The method of claim 1, The light emitting diode package comprising a lens provided on the upper side of the main body. The method of claim 1, The printed circuit board is a light emitting diode package, characterized in that the metal printed circuit board. The method of claim 1, The main body, A support having a central portion thereof; A heat sink slug mounted to the center portion of the support; A reflection cup installed in a cup shape on an upper surface of the sink slug; A silicon sub-mount in which a light emitting diode chip is thermally conductive paste bonded to the reflective cup; And A light emitting diode package comprising a cathode and an anode lead for electrically connecting the light emitting diode chip and the screw portion. A liquid crystal display panel; And A light emitting diode for irradiating light to the liquid crystal display panel, the light emitting diode including a plurality of main bodies each having a light emitting diode mounted thereon, a screw portion formed under each of the main bodies, and a printed circuit board fastened to the main bodies through the screw portion; A backlight unit comprising a package. The method of claim 5, And a lens installed on an upper side of the main body. The method of claim 5, The printed circuit board is a backlight unit, characterized in that the metal printed circuit board. The method of claim 5, The light emitting diode, A red light emitting diode for generating red light; A red light emitting diode for generating blue light; And And a red light emitting diode for generating red light. The method of claim 8, A light guide plate for mixing red light, green light, and blue light and converting the mixed light into a surface light source; A reflector disposed under the light guide plate to reflect light from the light emitting diode packages; And And a plurality of optical sheets positioned between the light guide plate and the liquid crystal display panel to diffuse light and increase brightness. The method of claim 9, The light emitting diode package is a backlight unit, characterized in that installed on both sides of the light guide plate. The method of claim 6, The light emitting diode packages are installed under the light guide plate, and the reflecting plate is installed between the main body of the light emitting diode package and the lens. The method of claim 5, The main body, A support having a central portion thereof; A heat sink slug mounted to the center portion of the support; A reflection cup installed in a cup shape on an upper surface of the sink slug; A silicon sub-mount in which a light emitting diode chip is thermally conductive paste bonded to the reflective cup; And And a cathode and an anode lead for electrically connecting the light emitting diode chip and the screw unit.

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