KR101248514B1

KR101248514B1 - Led package and its fabricating method, and dish reflector used for the same

Info

Publication number: KR101248514B1
Application number: KR1020060095657A
Authority: KR
Inventors: 조강현
Original assignee: 서울반도체 주식회사
Priority date: 2006-09-29
Filing date: 2006-09-29
Publication date: 2013-04-04
Also published as: KR20080029471A

Abstract

The present invention relates to a LED (Light Emitting Diode) package, and to provide an LED package having a means for reflecting and sending light to the outside of the package body at a close proximity to the LED chip.

To this end, the LED package according to the present invention includes a package body in which the internal space in which the LED chip is installed is opened in the light emitting direction, and a chip support member installed in the internal space of the package body to support the LED chip; And a dish reflector disposed on the chip support member, the dish reflector having an inclined side reflector surrounding the periphery of the LED chip placed inwardly through the opening and the bottom.

Dish Reflector, Heat Sink, Molding Lens, LED Chip, Fluorescent Resin

Description

LED package, manufacturing method thereof, and dish reflector used for the same {LED PACKAGE AND ITS FABRICATING METHOD, AND DISH REFLECTOR USED FOR THE SAME}

1 is a perspective view showing an LED package according to an embodiment of the present invention,

2 is an exploded perspective view showing an LED package according to an embodiment of the present invention with the molding lens removed;

3 is a cross-sectional view showing an LED package according to an embodiment of the present invention,

4 is a view for explaining the operation of the LED package according to an embodiment of the present invention,

5 to 7 are views for explaining the manufacturing method of the LED package according to an embodiment of the present invention.

(A brief description of the main symbols in the drawings)

10: package body 20: heat sink (or chip support member)

22: protrusion 30: lead frame

40: dish reflector 44: side reflector

442: wire groove 442: opening

52: fluorescent resin 60: molding lens

2: LED chip

The present invention relates to the field of LED (Light Emitting Diode) package, and more particularly, to an LED package having a dish reflector and a method of manufacturing the same.

In general, the LED package has a structure in which the LED chip for generating light by p-n junction inside the package body. The package body is opened in the light emitting direction of the LED chip through the opening, through which the light generated by the LED chip is emitted to the outside. In addition, the LED package includes a lens (especially a molding lens) covering the LED chip to increase the light emission efficiency within a certain direction angle of light. The lens is formed to cover the opening of the package body and is convex from the opening of the package body.

In a typical LED package, a large amount of light generated by the LED chip is not emitted to the outside through the lens, there is a problem of light loss that is lost inside the lens. This loss of light is mainly caused by the presence of light that does not direct to the lens covering the opening and the presence of light that hits the lens and then returns back.

Accordingly, there have been many studies to increase the amount of light directed to the lens. As a result of such research, a technique has been conventionally proposed in which the inner wall of the package body is formed to be inclined and the reflecting material is coated or the reflector is formed on the inclined inner wall. 61304 and the like. In prior art LED packages, the reflective inner wall in the package body reflected some of the light that was not directed to the lens towards the lens, thereby contributing to some extent reducing the light loss of the LED package.

However, in the conventional LED package, the distance between the reflective inner wall and the LED chip is far, so that the reflection efficiency of the light is inferior, and it is difficult to set the inclination angle of the reflective inner wall. In particular, the package is formed due to the installation of other components. Since it is limited to the upper part of the body, there is a limit in the reflection of light toward the side or the bottom of the LED chip. Furthermore, in conventional LED packages, in order to increase the light emission efficiency using the reflective inner wall, an extended design of the reflective inner wall is inevitable, which causes the compact size and structure of the LED package.

The technical problem of the present invention is to provide an LED package having a means for reflecting and sending light to the outside of the package body in close proximity to the LED chip.

Another technical problem of the present invention is to provide a method of manufacturing an LED package for disposing a means in the package body to reflect the light to the outside of the package body at a close proximity to the LED chip.

Another technical problem of the present invention is to provide a structure that can effectively reflect the light to the outside of the package body to the LED chip at a close distance.

According to an aspect of the present invention, an LED package includes a package body in which an internal space in which an LED chip is to be installed is opened in a light emitting direction, a chip support member installed in an inner space of the package body to support the LED chip, and the chip support. And a dish reflector positioned on the member, the dish reflector having an inclined side reflector surrounding the periphery of the LED chip placed inwardly through the opening. In the present specification, the term 'plate reflector' refers to a reflector having a substantially dish shape, and the present invention is not limited by the term.

The chip support member may be any means already known to support the LED chip, for example, lead frame, lead electrode, etc., but the heat from the LED chip is transferred to the outside while directly supporting the LED chip in a high power LED package. It is preferred to consist of a heatsink used to discharge.

At this time, the heat sink is preferably provided with a protruding end that is fitted to the opening of the dish reflector. Most preferably, the protruding end of the heat sink and the opening of the dish reflector are formed in a shape and size corresponding to each other to fix the rotational movement of the dish reflector. Here, the shape is preferably a polygon, such as a square, triangle, pentagon, hexagon, etc., but may be a variety of geometric shapes that are fitted to each other to limit the rotational direction relative to each other.

According to a preferred embodiment of the present invention, the protruding end has a flat end surface to which the LED chip is attached, and a fluorescent resin surrounding the LED chip is defined on the end surface. In addition, at least one wire groove is formed in the side reflector of the dish reflector to allow the passage of the bonding wire from the LED chip. The dish reflector is provided to cover the opening of the package body as a whole, and a convex molding lens made of a resin material is formed to cover an upper portion of the dish reflector. At this time, since the dish reflector covers the opening part as a whole, light is prevented from reaching the inner wall of the package body where light loss is likely to occur, and since it is located below the convex portion of the molding lens, it is easy to design a large overall height. Do.

According to another aspect of the present invention, a method of manufacturing an LED package including a package body in which the internal space in which the LED chip is to be installed is opened in the light emitting direction, and a chip support member installed in the internal space of the package body to support the LED chip. The manufacturing method includes a dish reflector having a bottom opening and an inclined side reflector, and the dish reflector being mounted on the chip support member such that the side reflector surrounds the periphery of the LED chip on the chip support member. It includes deploying.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the embodiment, it will be described as an example of an LED package including a heat sink that is used for the emission of heat generated from the LED chip as a chip support member for supporting the LED chip. However, the LED package including the heat sink described below does not limit the present invention, and the present invention may be limited only by the matters described in the claims.

Example

1 is a perspective view showing an LED package according to an embodiment of the present invention, Figure 2 is a perspective view showing a partially disassembled LED package according to an embodiment of the present invention with the molding lens removed, Figure 3 Is a cross-sectional view of the LED package shown in FIG.

2 and 3, the LED package 1 according to the present exemplary embodiment includes a package body 10 in which an internal space in which the LED chip 2 is to be installed is opened in the light emitting direction of the upper side. The package body 10 may be formed by sintering a ceramic or injection molding a plastic resin. An inner space of the package body 10 is installed as a heat sink 20 inserted therein, commonly referred to as a heat transfer 'slug'. In this case, the heat sink 20 may be replaced with a heat pipe.

In addition, a lead frame 30 is installed in the package body 10, and the inner leads 32 of the lead frame 30 are located in the periphery of the heat sink 20 in the package body 10. The outer lead 34 of the lead frame 30 extends to the outside of the package body 10 while being connected to the inner leads 32.

The heat sink 20 has a lower portion thereof exposed to the outside through the bottom opening of the package body 10, thereby easily dissipating heat of the LED chip 2 to the outside. In addition, the package body 10 has a bottom whose structure is blocked by the lower portion of the heat sink 20, while its upper end is opened for light emission and formation of a molding lens. The upper end of the heat sink 20 is formed with a protruding end 22 having a substantially rectangular cross section, and the LED chip 2 is attached to and supported on the end face of the protruding end 22.

The LED chip 2 is surrounded by a fluorescent resin 52 formed on the end surface of the protruding end 22. The fluorescent resin 52 is a liquid resin (hereinafter, a liquid fluorescent resin) containing a powder-type fluorescent material dotting on the end surface of the protrusion 22 is cured at the end surface of the protrusion 22 It is formed. In this case, the liquid fluorescent resin may be formed by being limited to the end surface of the protruding end 22 by the surface tension. As the fluorescent material of the fluorescent resin 52, various kinds of materials capable of color mixing with light generated from the LED chip 2 to implement white light may be used. By forming the fluorescent resin body 52 separately from the molding lens 60 (see FIG. 1), various conventional problems caused by uneven distribution of fluorescent materials in a relatively wide molding lens can be solved.

Meanwhile, the LED chip 2 is electrically connected to the inner leads 32 of the lead frame 30 by bonding wires 3. Each of the bonding wires 3 is connected to the opposite polarity electrodes of the LED chip 2, respectively, and passes through the wire grooves 442 of the dish reflector 40 described below. Connected to the field.

The LED package 1 according to the present embodiment is a dish reflector 40 for reflecting light from the LED chip 2 at a predetermined angle while being disposed on the heat sink 20 serving as a member for supporting the chip. ). The dish reflector 40 includes a flat bottom 42 and side reflectors 44 extending obliquely from the bottom. The dish reflector 40 may be formed of a metal material having excellent reflectivity, or may be formed by metal coating the entire surface while being formed of a non-metal such as resin, or by metal coating only the side reflector 44 where light is mainly reflected. have. In particular, the dish reflector 40 may cover the upper opening of the package body 10 as a whole to block light from reaching the inner wall of the package body 10 that is prone to light loss.

An opening 422 is formed at the bottom of the dish reflector 40 to fit into the protruding end 22 of the heat sink 20. The protruding end 22 and the opening 422 are formed in a shape corresponding to each other. In this embodiment, the protruding end 22 is formed in a rectangular cross section, and the opening 422 is also formed in a corresponding square. . Accordingly, the dish reflector 40 has its opening 422 fitted into the protrusion 22 of the heat sink 20 so that the movement in the rotational direction can be suppressed.

In addition, the LED chip 2 attached to the protruding end 22 and the fluorescent resin 52 surrounding it are placed inside the dish reflector 40 through the opening 422, and thus, the dish reflector The inclined side reflector 44 of 40 is directed toward the side and / or the bottom of the light generated by the LED chip 2 that does not direct to the molding lens 60 (shown in FIGS. 2 and 3) which will be described below. The light may be reflected and directed toward the upper opening of the package body 10 or the molding lens 60. In addition, the side reflector 44 has a substantially conical curved surface centering on the LED chip 2, and thus may have regular and uniform light reflection characteristics in the circumferential direction.

As mentioned above, the dish reflector 40 has two wire grooves 442 at the top of the side reflector 44 allowing the passage of two bonding wires 3. Therefore, the bonding wire 3 connected to the LED chip 2 may lead to the inner leads 32 of the lead frame 30 without going through a distant path despite the presence of the dish reflector 40. At this time, the wire groove 442 may be formed in the form of a hole formed in the middle of the side reflector 44, not the top of the side reflector 44.

As shown in FIGS. 1 and 3, a molding lens 60 is formed at an upper opening of the package body 10, and the molding lens 60 is formed in a hemispherical convex structure in a light emission direction. do. Although not shown, the molding lens 60 is formed by a mold molding technique, and a mold having a resin injection hole on the upper portion of the package body 10 is hypothesized, and a transparent epoxy or transparent silicone is formed on the injection hole of the mold. It is formed by injecting the same liquid resin. At this time, the mold has an internal shape or a void shape corresponding to the molding lens 60, of course.

A part of the light generated by the LED chip 2 may not pass through the molding lens 60 due to total internal reflection and may return back to the floor. In this case, the dish reflector 40 may minimize the light loss caused by a portion of the light not passing through the molding lens 60.

4 is a view for explaining the operation of the dish reflector 40, FIG. 4 shows a portion of the light reflecting directly from the LED chip and part of the light returned without passing through the molding lens 60. The action of reflecting toward 60 is indicated by an arrow. The dish reflector 40 reflects the light returned from the molding lens 60 after being hit by the molding lens 60, and sends the light back toward the molding lens 60. It contributes to greatly suppressing the light loss due to the impact on.

Hereinafter, a manufacturing method of the LED package 1 according to the embodiment of the present invention will be described with reference to FIGS. 5 to 7. In the following description, the process of installing the heat sink 20 and the lead frame 30 on the package body 10 follows the conventional method, and thus detailed descriptions in the drawings and the specification will be omitted.

As shown in FIG. 5, the LED chip 2 is adhered to the protruding end 22 of the upper end of the heat sink 20 serving as the support member of the LED chip 2, and as shown in FIG. 6, the dish reflector 40 is disposed on the heat sink 20. At this time, the flat bottom 42 of the dish reflector 40 is seated on the flat surface of the heat sink 20, and the heat sink having a rectangular cross section corresponding to the rectangular opening 422 of the bottom of the dish reflector 40 is formed. 20 is fitted snugly against the protruding end 22. Accordingly, the dish reflector 40 may be kept fixed at the desired position on the heat sink 20. It is also possible to reverse the order of the process shown in FIG. 5 and the process shown in FIG. 6.

Then, each electrode of the LED chip 2 and the lead frame are connected with the bonding wire 3. The liquid epoxy or silicone resin, ie, the liquid fluorescent resin containing the fluorescent material, is doped to the protruding end 22 of the heat sink 20 to which the LED chip 2 is attached. The liquid fluorescent resin doped in the protruding end 22 is limited to the end face of the protruding end 22 by surface tension to form a fluorescent resin 52 as shown in FIG. 7.

In the position where the LED chip 2 enclosed by the fluorescent resin 52 as shown in FIG. 7 is surrounded by the dish reflector 40, the molding lens 60 as shown in FIGS. 1 and 3 is shown. ) Is formed near the top opening of the package body 10 so as to surround the LED chip 2, the fluorescent resin 52, and the dish reflector 40.

In the foregoing embodiments, it has been described that the LED chip 2 is supported on the heat sink 20 and the dish reflector 40 surrounds the periphery of the LED chip 2 with the dish reflector 40 disposed on the heat sink 20. There is a bar. However, when the LED chip 2 is supported by a lead frame or lead electrode rather than the heat sink 20, the dish reflector 40 surrounds the periphery of the LED chip 2 on the lead frame or lead electrode. It may be arranged.

While the present invention has been particularly shown and described with reference to specific embodiments thereof, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the present invention as defined by the appended claims. And should not be construed as limiting the scope of the present invention, but rather should be construed as exemplifying the invention.

According to the embodiment of the present invention, by adopting a dish reflector reflecting light to the outside of the package body in a position close to the LED chip, it is possible to minimize the amount of light loss in the package body. In addition, in the LED package according to the embodiment of the present invention, since the LED chip is surrounded by the fluorescent resin inside the dish reflector, almost all of the light converted into white light by the fluorescent resin can be emitted to the outside of the package body without light loss. That has the advantage.

Claims

A chip support member for supporting the LED chip;

A dish reflector positioned on the chip support member, the dish reflector having an inclined side reflecting portion surrounding the periphery of the LED chip placed inwardly through the opening and bottom;

The chip support member has a protruding end fitted into the opening of the dish reflector.

delete

The LED package according to claim 1, wherein the protruding end and the opening are formed in a shape to fix a rotational direction of the dish reflector.

The LED package according to claim 1, wherein the protruding end has a flat end surface to which the LED chip is attached, and a fluorescent resin surrounding the LED chip is defined on the end surface.

The LED package according to claim 1, wherein at least one wire groove is formed in a side reflector of the dish reflector to allow bonding wires connected from the LED chip to pass therethrough.

The apparatus of claim 1, further comprising a package body in which an internal space in which the LED chip is to be installed is opened in a light emitting direction, wherein the chip support member is installed in an inner space of the package body to support the LED chip, and the dish reflector Is provided to cover the entire opening of the package body, LED package, characterized in that the convex molding lens of the resin material is formed to cover the upper plate reflector.

In the method of manufacturing an LED package comprising an LED chip and a chip support member for supporting the LED chip,

Preparing a dish reflector having an opening at the bottom and a flat bottom and an inclined side reflector around the opening,

The flat bottom is seated on a flat surface of the chip support member, and the dish reflector is disposed on the chip support member such that the side reflector can surround the periphery of the LED chip on the chip support member. Method of making the package.

The method of claim 7, wherein the chip support member is a heat sink having a protruding end fitted into an opening of the dish reflector.

The method of manufacturing an LED package according to claim 8, wherein the opening and the protruding end are configured in a shape and a size corresponding to each other to suppress a rotational direction movement of the dish reflector.

The method according to claim 9, wherein the LED chip is attached to the end surface of the protruding end, doping a liquid resin containing a fluorescent material on the end surface, to form a fluorescent resin surrounding the LED chip on the end surface LED package manufacturing method characterized in that.

The method of claim 10, wherein a molding lens is formed to cover the LED chip and the dish reflector surrounded by the fluorescent resin.

Dish reflector around the LED chip disposed on the chip support member for supporting the LED chip,

An inclined side reflector having an opening at a bottom to receive the LED chip inwardly through the opening, and reflecting light while surrounding the LED chip housed therein;

The chip support member is provided with a protruding end, wherein the opening has a shape and size corresponding to the protruding end and is fitted to the protruding end.

delete

The dish reflector of claim 12, wherein the side reflector includes at least one wire groove for allowing passage of a bonding wire from the LED chip.