KR20070065733A - Side emitting light emitting diode package - Google Patents

Abstract

A side LED(light emitting diode) package is provided to maximize light intensity by avoiding front light emission. A parabolically curved surface is formed in a substrate. A light emitting chip is formed on the substrate. A lens part is mounted on the substrate to cover the parabolically curved surface, including a total reflection surface which laterally reflects the light from the light emitting chip. A reflection surface can be included on the parabolically curved surface in the substrate. The reflection surface can reflect the light emitted from the light emitting chip and changes the reflected light to horizontal light with respect to the parabolically curved surface.

Description

Side emitting light emitting diode package

1 is a cross-sectional view of a side light emitting diode package according to the prior art.

2 is a cross-sectional view of a side light emitting diode package according to an embodiment of the present invention.

3 is a view illustrating a parabolic curved surface formed on a substrate of a side light emitting diode package according to the present invention.

4 is a cross-sectional view of a side light emitting diode package according to another embodiment of the present invention.

5 is a perspective view of a side light emitting diode package according to another embodiment of the present invention.

* Description of the main parts of the drawings *

31: Substrate

32: light emitting chip

33: lens unit

34: metal reflective surface

36: total slope

The present invention relates to a light emitting diode package for side emitting.

More specifically, the present invention relates to a side light emitting diode package, and not only the shape of the lens portion but also the inner wall shape of the reflecting portion is modified so as to increase the light intensity of the side light emission, the side light emitting diode package with improved brightness.

In general, a light emitting diode (LED) is a device using a phenomenon in which a small number of carriers (electrons or holes) are injected by using a p-n junction structure of a semiconductor and emit light by recombination thereof. A light source system using such a light emitting diode is mounted and used in various types of packages according to the intended use of a light emitting diode (LED) emitting light.

1 is a cross-sectional view of a side light emitting diode package according to the prior art.

Referring to FIG. 1, the side light emitting diode package encapsulates the substrate 100, the light emitting chip 110 mounted on the substrate 100, and the light emitting chip 110, and has a predetermined slope in the center thereof. A first total reflection surface 121 having a V shape and a second total reflection surface 122 having a gentler slope than that of the first total reflection surface 121 are formed and extend from the second total reflection surface 122. And a lens 120 having a downwardly rounded refractive surface 123.

As described above, the side light emitting diode package according to the related art is designed to emit light output from the light emitting chip to both sides based on the lens center axis through the shape of the lens. However, when the path of the light emitted from the light emitting chip is converted using only the shape of the lens, the shape of the lens is complicated, which makes it difficult to manufacture, and also does not completely block the light emitted to the center of the lens.

It is an object of the present invention to provide a side light emitting diode package in which the light emitted to the center of the lens is completely blocked to improve the light intensity of the side light.

An object of the present invention is to provide a side light emitting diode package in which the brightness of side light emission is improved by improving the shape of not only the reflecting portion but also the transparent molding portion, that is, the portion corresponding to the lens portion.

A substrate having a parabolic curved surface in a side light emitting diode according to an embodiment of the present invention; And a lens unit mounted on the substrate to cover the parabolic curved surface and the light emitting chip mounted on the substrate, and including a total reflection surface that totally reflects light from the light emitting chip to the side.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2 is a cross-sectional view of a side light emitting diode package according to an embodiment of the present invention. The side light emitting diode package according to the present invention includes a substrate 31 on which the light emitting chip 32 is mounted and a lens unit 33 of a transparent material. The inner wall of the substrate 31 forms a parabolic curved surface and is coated with a metal material as the metal reflective surface 34. For example, the metal reflective surface 34 may be coated with a material such as silver (AG) to improve the reflectance.

The substrate 31 may be made of an insulating material, and may include an electrode pad (not shown) or a lead frame (not shown) for mounting and electrically connecting the light emitting chip 32.

The inner wall of the substrate 31 according to the present invention is formed so as to form part of the secondary parabolic curve, as shown in FIG. Further, the light emitting surface of the light emitting chip 32, preferably the light emitting chip 32, is disposed on the focal point 38 of the parabolic curve. Therefore, the light emitted from the light emitting chip 32 can all be seen to be emitted from the focal point 38, among which the light 40 reflected from the parabolic curved surface is vertically upwardly reflected toward the lens unit 33. do. At this time, the metal reflective surface 34 improves the reflectance of the reflected light.

As shown in FIG. 2, the lens unit 33 has a total reflection surface of a conical shape inverted at the center portion. The lens portion 33 includes a transparent resin such as epoxy or silicone resin. The total reflection surface formed on the lens portion 33 serves to totally reflect the light emitted directly from the light emitting chip 32 or reflected from the metal reflection surface 34 to the side surfaces.

Total reflection refers to a phenomenon in which incident light is reflected when the incident angle is greater than or equal to the critical angle when the incident light enters the medium (small refractive index material) from the optically dense medium (large refractive index material). Since it is a more dense material, the total reflection occurs when only the critical angle at which total reflection can be made occurs, and the light emitted from the upper portion of the lens unit 33 is completely absent.

In order to achieve total reflection, the cone-shaped angle formed in the lens part 33 should be formed to be larger than the critical angle with respect to light incident from the lower surface of the lens part 33.

Looking at the light path of the light emitted from the light emitting chip 32 in more detail as follows. Light emitted from the light emitting chip 32 is emitted to the outside with three paths, that is, to the side of the substrate 31.

The first path (A) is a case of reflecting from the parabolic surface of the metal reflective surface 34, in which the reflected light is all advanced upward and totally reflected from the total reflection surface 36 is emitted to both sides. The total reflection surface 36 has an inclination angle that satisfies the total reflection condition with respect to the incident horizontal light. The parabolic reflective surface formed on the substrate 31 is the core of the present invention.

The second path B is a case where the light output from the light emitting chip 32 is totally reflected at the total reflection surface 36 to emit light toward the lens side without passing through the metal reflective surface 34.

The third path C is a case where the light output from the light emitting chip 32 passes through the lens side without passing through the metal reflecting surface 34 and is not totally reflected on the lens unit 33 but is only transmitted through refraction.

It is preferable to use a transparent epoxy resin or a silicone resin as the material of the lens unit 33, but since it may cause total reflection at the contact surface with air, any transparent resin may be used as the lens unit 33 according to the embodiment. have.

In addition, the lens unit 33 may include a diffusing agent or a phosphor capable of scattering light from the light emitting chip 32 to excite various wavelengths.

The lens unit 33 uses a resin that is cured by heat or UV irradiation, and is molded using a variety of molding methods according to manufacturing methods such as transfer molding and injection molding, and then cured through heat or UV irradiation. Can be formed.

In addition, according to the embodiment, a blue light emitting diode is used as the light emitting chip 32 to form the lens unit 33, and a light emitting diode which mixes phosphors inside the lens unit 33 and outputs white light. In addition, a light emitting diode that outputs various colors may be implemented using light emitting diodes such as red, green, and blue.

2 and 3, according to the structure of the present invention, the light emitted from the light emitting chip 32 is not emitted to the front surface of the substrate 31 and is emitted only to the side to require side light emission. In this case, the light utilization efficiency can be maximized.

4 and 5 are cross-sectional and perspective views, respectively, of a side light emitting diode package according to another embodiment of the present invention.

Like the embodiment shown in FIG. 2, the side light emitting diode package according to the present invention includes a substrate 31 on which the light emitting chip 32 is mounted and a lens unit 33 of a transparent material. The inner wall of the substrate 31 forms a parabolic curved surface and is coated with a metal material as the metal reflective surface 34. For example, the metal reflective surface 34 may be coated with a material such as silver (AG) to improve the reflectance.

However, the lens unit 33 is not cylindrical but has a dome shape, and has a conical inverted total reflection surface formed inside thereof. Since the circumference of the lens portion 33 is circular, some refraction is formed on the side of the lens portion 33, so that the side light emission can be widely spread.

4 and 5 may be formed in the same manner as in the embodiment of FIG. 3 by molding by changing a molding frame when molding an epoxy resin or a silicone resin.

The description of the other components is the same as the embodiment shown in Figs.

According to the present invention can provide a side light emitting diode package with improved brightness.

According to the present invention, there is no front emission at all, thereby providing a side light emitting diode package having maximum brightness.

According to the present invention, the brightness may be improved by improving the shape of not only the reflecting portion but also the transparent molding portion, that is, the portion corresponding to the lens portion.

Although the present invention has been described above with reference to the embodiments, the above-described embodiments are exemplified as an example, and the scope of the present invention is defined by the following claims, and those skilled in the art can implement the above within the scope of the present invention. It will be understood that various modifications may be made to the examples, all of which are included in the scope of the present invention.

Claims (7)

A substrate having a parabolic curved surface therein; A light emitting chip mounted on the substrate; And a lens unit mounted on the substrate to cover the parabolic surface, the lens unit including a total reflection surface that totally reflects light from the light emitting chip laterally. The method of claim 1, The parabolic curved surface forms a part of a secondary parabolic curve focusing on the center of the light emitting chip. The method of claim 1, And a reflective surface formed on a parabolic surface of the substrate. The method according to any one of claims 1 to 3, The reflective surface is a side light emitting diode package for converting the light emitted from the light emitting chip to the horizontal light for the parabolic curved surface. The method according to any one of claims 1 to 3, The lens unit is a side light emitting diode package, characterized in that made of epoxy resin or silicone resin. The method according to any one of claims 1 to 3, The lens unit is a side light emitting diode package having a dome or cylindrical shape. The method according to any one of claims 1 to 3, The reflective surface is a side light emitting diode package coated with a metal material.

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