KR100585917B1 - Light emitting diode - Google Patents

Abstract

The present invention relates to a light emitting diode, and includes a light emitting chip, a package molding part encapsulating the light emitting chip, and a plurality of beads distributed in the package molding part. According to this, the light emission characteristics, in particular, the luminance is increased, and the range of the light path and the viewing angle is increased.

In addition, the present invention further includes a phosphor in the package molding part, thereby manufacturing a white light emitting diode having high brightness and uniform color distribution characteristics.

Bead, Luminance, Phosphor, Light Emitting Diode, Package Molding Part, Light Emitting Characteristics, LED

Description

Light emitting diodes             

1 is a longitudinal sectional view of a chip type light emitting diode according to a first embodiment of the present invention;

2 is a longitudinal cross-sectional view of a tower light emitting diode according to a second embodiment of the present invention;

3 is a longitudinal sectional view of a lamp type light emitting diode according to a third embodiment of the present invention;

4 is a longitudinal cross-sectional view of a tower white light emitting diode according to a fourth embodiment of the present invention;

5 is a longitudinal cross-sectional view of a general chip type light emitting diode.

<Explanation of symbols for the main parts of the drawings>

1, 20, 30, 40: light emitting diode

3: printed circuit board

5: light emitting chip

7, 9, 31,33: lead

11, 27, 35: package molding

16: bead

25: Reflector

43: phosphor

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to light emitting diodes, and more particularly to chip type, tower type and lamp type light emitting diodes having improved structure of the package molding part, and various types of white light emitting diodes.

Light emitting diodes are expected as a next-generation item with infinite growth potential as it is widely applied to lighting products. However, the adoption of a general-purpose lighting product is still not satisfactory level of brightness and price per unit device.

Among the light emitting diodes, a chip type light emitting diode includes a metal pad 52 and a lead 55 provided on a printed circuit board 51, and a light emitting chip 53 on the metal pad 52. This is implemented. The light emitting chip 53 is connected to the lead 55 via the conductive wire 54. The light emitting chip 53 and the lead 55 connected by the wire 54 are formed on the printed circuit board 51 by the package molding part 56 molded with, for example, an epoxy mold compound (EMC). It is sealed.

Such light emitting diodes have difficulty in greatly improving their light emitting characteristics due to their light and simple product characteristics. In spite of the difficulties, the research and development for the improvement of the characteristics is being actively performed for each essential component, and many research results on the package molding part have been proposed.

For example, Korean Patent No.0405453, previously filed and registered by the same applicant of the present invention, is an invention in which the structure of the LED package molding part is improved. Referring to this, it can be seen that the structure of the package molding part can be improved to improve its emission characteristics, in particular, the range of the light path and the viewing angle.

Accordingly, an object of the present invention is to provide a light emitting diode having improved light emitting characteristics, in particular, brightness and improved range of light path and visible angle by improving the structure of the LED package molding part.

Another object of the present invention is to provide a white light emitting diode having high latitude and uniform color distribution characteristics.

According to the present invention, the object is achieved by a light emitting diode comprising a light emitting chip, a package molding part encapsulating the light emitting chip, and a plurality of beads distributed in the package molding part. According to this, since the light from the light emitting chip is reflected by the plurality of beads and scatters radially, the light path and the direction of the light are widened.

Here, it is preferable to distribute the plurality of beads in the vicinity of the surface of the package molding part. In this case, since the surface of the package molding part has an uneven shape, it is advantageous to change the light emission characteristics.

When the package molding part includes a phosphor for converting light having a predetermined wavelength from the light emitting chip into light having a specific wavelength, a white light emitting diode having high luminance and uniform color distribution can be provided.

Hereinafter, a light emitting diode of the present invention will be described in detail with reference to the accompanying drawings.

1 is a longitudinal sectional view of a chip type light emitting diode according to a first embodiment of the present invention. The chip type light emitting diode 1 of the first embodiment has a printed circuit board 3, a pair of leads 7 and 9 provided on the printed circuit board 3, as described with reference to FIG. A light emitting chip 5 mounted on one lead 7 and a wire 14 connecting the light emitting chip 5 and the other lead are provided. Here, a package molding part 11 is formed to protrude on the printed circuit board 3 and to partially mold the leads 7 and 9 with the light emitting chip therebetween.

The leads 7 and 9 are made of a material that can be energized on the printed circuit board 3. The light emitting chip 5 may be selectively adopted among chips that emit light in the infrared region from the infrared region. Descriptions of materials and characteristics of the leads 7 and 9 and the light emitting chip 13 are well known and detailed descriptions thereof will be omitted.

On the other hand, the package molding portion 11 protrudes in a round shape on the printed circuit board (3). The package molding part 11 may be simply formed by a transfer molding method using, for example, a mold having a round cavity, and a plurality of beads 16 may be distributed in the package molding part 11. have.

The beads 16 may be made of a material that reflects light from the light emitting chip 13, and may be, for example, glass, polymer plastic, metal, ceramic, or the like made of a transparent material. In consideration of the case in which the package molding part 11 is manufactured by a transfer molding method, the beads 16 are preferably made of a material resistant to heat.

Here, the plurality of beads 16 may be evenly distributed in the package molding part 11, but as shown in the drawing, the beads 16 may be intensively distributed in the surface area of the package molding part 11. The beads 16 distributed near the surface of the package molding part 11 partially enlarge the outer surface of the package molding part 11 so as to be convex as shown to have an uneven shape as a whole. Such a structure is advantageous for scattering light from the light emitting chip 5 to improve its light emitting characteristics.

Meanwhile, although the package molding part 11 of the chip type light emitting diode according to the present embodiment is illustrated in a round shape, the same may be applied to the polygonal package molding parts of various forms.

2 is a longitudinal sectional view of a tower light emitting diode according to a second embodiment of the present invention. The top light emitting diode 20 of the second embodiment has components similar to those of the first embodiment described above with reference to FIG. 1, and further adds a reflector 25, and the package molding portion 27 therein. ) Is formed. The description of the same configuration is omitted, and the same reference numerals are used for the same configuration and names below.

The reflector 25 has a cavity 26 for accommodating the leads 7 and 9 and the light emitting chip 5 mounted thereon. The reflector 25 may be manufactured integrally with the printed circuit board 3 or separately manufactured and then adhered to the printed circuit board 3. The inner surface forming the cavity 26 of the reflector forms a predetermined inclined surface, whereby the light generated from the light emitting chip is reflected upward. Reflective materials or reflectors can be added to the inner surface for effective reflection of light.

The package molding part 27 is formed in the cavity 26 of the reflector 25 to encapsulate the light emitting chip 5, the conductive wire 14, and the leads 7 and 9. Also in this package molding portion 27, a plurality of beads 16 are distributed as in the first embodiment described above. Beads 16 may be evenly distributed throughout the package molding 27 but may be concentrated near the surface of the package molding. The effect by this is the same as that of the first embodiment.

Here, the package molding portion 27 formed in the reflector 25 is preferably such that the surface thereof has a round shape. Then, the surface of the package molding part 27 acts as a convex lens, and the light transmitted to the outside is concentrated to the center area.

3 is a longitudinal sectional view of a lamp type light emitting diode according to a third embodiment of the present invention. The lamp type light emitting diode 30 shown in FIG. 3 includes a mount lead 31 and an inner lead 32, and a light emitting chip 5 is provided in the cup portion 33 of the mount lead 31. The light emitting chip 5 is connected via the inner lead 32 and the conductive wire 14.

The cup part 33 including the light emitting chip 5 is entirely sealed by the package molding part 35. In the package molding part 35 of the present embodiment, as described above with reference to FIGS. 1 and 2, a plurality of beads 16 are distributed. The beads 16 are concentrated near the surface of the package molding part 35, whereby the outer surface of the lamp type light emitting diode 30 has an uneven shape. Of course, the plurality of beads 16 may also be evenly distributed throughout the package molding part 35.

Hereinafter, the operation of the light emitting diodes according to the first to third embodiments will be described. When external power is supplied to the light emitting chip 5 through the leads 7, 9, 31, and 33, the light emitting chip 5 generates light having its own wavelength. The generated light travels upwards in the structure of each embodiment and reflects against the beads 16 present on its path. The light reflected by the plurality of beads 16 is scattered radially as a whole, and the optical path is changed, and then is transmitted through the outer surface of the corresponding package molding part.

In the related art, since the path of light generated and propagated in the light emitting chip is constant, the angle of refraction of the light on the surface of the package molding part is constant, whereby a relatively large amount of light moves along the surface of the package molding part or is reflected inside and disappeared There are many cases. However, according to the present invention, as the path of the light is changed, the amount of light that passes through the surface of the package molding part and radiates to the outside increases, thereby increasing the luminance and increasing the range of the viewing angle.

4 is a longitudinal sectional view of the tower white light emitting diode according to the fourth embodiment of the present invention. The light emitting diode 40 shown in FIG. 4 has the same configuration as the second embodiment described with reference to FIG. 2 and further includes a phosphor 43 distributed in the package molding portion 35. The phosphor 43 performs a function of converting light of a specific wavelength emitted from the light emitting chip 5 into light of a specific wavelength. Since the description of the phosphor 43 is generally omitted, in the present embodiment, a light emitting chip 5 for emitting blue wavelength light and a phosphor 43 for converting light emitted from the light emitting chip 5 into white light are used. Will be described as an example.

The phosphor 43 may be concentrated in the lower portion of the package molding portion 27, that is, in the region of the light emitting chip 5, but more preferably, the phosphor 43 is evenly distributed throughout the package molding portion 27. In order to distribute the phosphor 43 evenly to the package molding part 27, a transfer molding method may be used.

A plurality of beads 16 are also mixed in the package molding portion 27 in which the phosphor 43 is distributed. The plurality of beads 16 convert the path of the white light generated by the light emitting chip 5 and then wavelength-converted by the phosphor 43, whereby a large amount of light is emitted to the outside. Here, the plurality of beads 16 may be evenly distributed along the phosphor 43 and the entire package molding part 27, but may be distributed near the surface of the package molding part 27 to further increase light emission characteristics. Of course.

As described above, according to the present invention, a light emitting diode including a plurality of beads in a package molding part to increase its light emission characteristics, in particular, brightness, and to improve a range of light path and viewing angle is provided. Concentrating the distribution of beads in the package molding near the surface can further enhance the above effect.

In addition, the inclusion of the phosphor in addition to the plurality of beads in the package molding portion of the present invention, there is provided a white light emitting diode having high brightness and uniform color distribution characteristics.

Claims (4)

Light emitting chip; A package molding part encapsulating the light emitting chip; A phosphor distributed in the package molding part and converting light emitted from the light emitting chip into light having a specific wavelength; And a plurality of beads distributed in the surface area of the package molding part to convert a path of light emitted from the light emitting chip and wavelength converted by the phosphor. The method according to claim 1, Light emitting diode, characterized in that the surface of the package molding portion has a concave-convex shape. The method according to claim 1, The phosphor is evenly distributed throughout the package molding portion. delete

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