KR20140141965A - Light emitting device package and lighting apparatus using the same - Google Patents

Abstract

The present invention relates to a light emitting device package and a lighting apparatus using the same for increasing light quality. The light emitting device package includes: a light emitting element including a first light emitting element which is located on a package main body and emits the light of a first wave band, and a second light emitting element which emits the light of a second wave band; a lens which is located on the light emitting element; and a wave converting layer which is located on the lens.

Description

TECHNICAL FIELD [0001] The present invention relates to a light emitting device package and a lighting apparatus using the same,

The present invention relates to a light emitting device, and more particularly, to a light emitting device package capable of improving the quality of light and a lighting device using the same.

Recently, research has been conducted on a light source, a light emitting method, a driving method, and the like for a lighting device. Recently, a light emitting device having advantages such as efficiency, color diversity, and design autonomy has been attracting attention as an illumination light source.

In particular, a light emitting diode (LED) generates light by exciting electrons across a band gap between a conduction band and a valence band of a semiconductor active (light emitting) layer. The electron transition generates light with a wavelength corresponding to the bandgap. Therefore, the color (wavelength) of the light emitted by the light emitting diode depends on the semiconductor material of the active layer of the light emitting diode.

On the other hand, color reproduction is generally measured using a color rendering index (CRI Ra). CRI Ra is a modified average value of the relative measure of the color rendering of the illumination system compared to the color rendition of the reference radiator when illuminating with eight reference colors. That is, it is a relative measure of the shift in the surface color of the object when illuminated by a particular lamp.

Since light perceived as white is basically a mixture of two or more colors (or wavelengths), a single light emitting diode junction that generates white light has not been developed.

For example, the white light emitting diode package includes light emitting diode pixels / clusters formed of red, green, and blue light emitting diodes, respectively, to generate light perceived as white light when red light, green light, and blue light are mixed .

As another example, the white light emitting diode package includes a light emitting diode that generates blue light, and a light emitting material, for example, a phosphor that is excited by the light emitted by the light emitting diode to emit yellow light, And generates light perceived as white light when light is mixed.

In implementing such white light, research is needed to improve color quality such as color rendering.

SUMMARY OF THE INVENTION The present invention provides a light emitting device package capable of improving light uniformity and efficiency and a lighting apparatus using the same.

Another object of the present invention is to provide a light emitting device package capable of improving color rendering and a lighting device using the same.

According to an aspect of the present invention, there is provided a light emitting device package comprising: a first light emitting device that emits light in a first wavelength band and a second light emitting device that emits light in a second wavelength band; A light emitting element including a light emitting element; A lens positioned on the light emitting element; And a wavelength conversion layer disposed on the lens.

Here, a spherical lens can be used as the lens.

Further, the wavelength conversion layer may have a constant thickness on the lens.

At this time, the thickness of the wavelength conversion layer may be smaller than the thickness of the lens.

Here, the first light emitting device and the second light emitting device may include a plurality of light emitting devices emitting light of substantially the same wavelength band, respectively.

At this time, the first light emitting element may be positioned symmetrically with respect to the second light emitting element.

More specifically, the second light emitting element may be located on the center side of the package body, and the first light emitting element may be located on both sides of the second light emitting element.

On the other hand, the wavelength conversion layer can absorb light emitted from the light emitting element and output light in a yellow band.

Here, the first wavelength band may be a blue band and the second wavelength band may be a red band.

At this time, the main wavelength of the first wavelength band is 450 nm, the main wavelength of the second wavelength band is 615 nm, and the wavelength of the main output of the wavelength conversion layer may be 555 nm.

A lighting apparatus including such a light emitting device package can be provided.

The present invention has the following effects.

First, the wavelength conversion layer for converting the wavelength of light of the light emitting element is not in contact with the light emitting element, but is located at least apart from the light emitting element by the thickness of the lens. The light efficiency of the phosphor used in the wavelength conversion layer is reduced by heat. Since the phosphor is located away from the light emitting element that is a heat source, it is possible to mitigate the reduction in efficiency due to heat.

Further, the area of the wavelength conversion layer is high enough to cover all of the light flux of the light emitting element, so that high efficiency of light conversion and optical output can be obtained.

Therefore, the light emitted from the first light emitting element and the light emitted from the second light emitting element pass through the wavelength conversion layer, and the light and the light converted by the wavelength conversion layer are uniformly mixed with each other, Light can be obtained.

The technical effects of the present invention are not limited to those mentioned above, and other technical effects not mentioned can be clearly understood by those skilled in the art from the following description.

1 is a schematic plan view showing an example of a light emitting device package.
2 is a sectional view taken along line A-A in Fig.
3 is a perspective view showing an example of a light emitting device package.
4 is an exploded perspective view showing an example of a light emitting device package.
5 is a graph showing an example of the light distribution of the light emitting device package.
6 is a perspective view showing an example of a lighting apparatus using a light emitting device package.
7 is an exploded perspective view showing an example of a lighting apparatus using a light emitting device package.

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

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. Rather, the intention is not to limit the invention to the particular forms disclosed, but rather, the invention includes all modifications, equivalents and substitutions that are consistent with the spirit of the invention as defined by the claims.

It will be appreciated that when an element such as a layer, region or substrate is referred to as being present on another element "on," it may be directly on the other element or there may be an intermediate element in between .

Although the terms first, second, etc. may be used to describe various elements, components, regions, layers and / or regions, such elements, components, regions, layers and / And should not be limited by these terms.

1 is a schematic plan view showing an example of a light emitting device package, and Fig. 2 is a sectional view taken along the line A-A in Fig.

1 and 2, the light emitting device package 500 is mounted on the package body 100 with the light emitting device 200.

The package body 100 may be formed of any one of ceramics, semiconductors, and metals, or a combination thereof.

Particularly, when it is made of a material such as a semiconductor and a metal, the heat releasing property can be more excellent. That is, heat emitted from the light emitting device 200 can be effectively emitted.

The package body 100 may have a mounting groove (not shown) in which the light emitting device 200 can be mounted. Although the mounting groove is not specifically shown, it may be formed in a recessed shape in the first region 110 where the lens 300 on the package body 100 is located.

The second region 120 where the wavelength conversion layer 400 is located may be located outside the first region 110 where the lens 300 is located. That is, the wavelength conversion layer 400 may be attached to the lens 300 and also to the second region 120 of the package body 100.

In addition, a reflection layer may be provided in the mounting groove to increase the extraction efficiency of light emitted from the light emitting device 200.

The package body 100 may include a lead (not shown) electrically connected to the light emitting device 200 and connected to an external power source. Hereinafter, a description of matters related to the package main body 100 will be omitted.

The light emitting device 200 may include first light emitting devices 210 and 220 that emit light in a first wavelength band and second light emitting devices 230 that emit light in a second wavelength band.

Here, the first and second light emitting devices 210 and 220 and the second light emitting device 230 may include a plurality of light emitting devices emitting light of substantially the same wavelength band.

A lens 300 for focusing and emitting light emitted from the light emitting device 200 may be disposed on the light emitting device 200.

The lens 300 may serve to protect and seal the light emitting device 200. The lens 300 may be manufactured using a light-transmitting resin. As an example of the light transmitting resin, it may be made of an epoxy series or a silicone series resin.

As shown in the figure, the light emitting device 200 is positioned so as to have high symmetry with respect to the lens, so that the light emitted from the light emitting device 200 can be effectively extracted.

The lens 300 may be directly injected onto the light emitting device 200, and may be mounted on the light emitting device 200, as the case may be.

As shown in FIG. 2, such a lens 300 can use a spherical lens whose outer surface is spherical. However, the present invention is not limited to this, and it is needless to say that an aspherical lens of parabolic shape, elliptical shape or the like may also be used in some cases.

A wavelength conversion layer 400 may be provided on the lens 300 to absorb light emitted from the light emitting device 200 and emit light in a specific wavelength band.

The wavelength conversion layer 400 may have a predetermined thickness on the lens 300. That is, it may be in direct contact with the lens 300 and have the same outer surface as the curved surface of the lens 300.

At this time, the thickness of the wavelength conversion layer 400 may be smaller than the entire thickness of the lens 300.

The wavelength conversion layer 400 may be a layer in which a phosphor material is uniformly distributed.

Such a phosphor may be a silicate-based fluorescent material, a sulfide-based fluorescent material, a nitride-based fluorescent material, or a mixture thereof. However, the present invention is not limited to this, and any material that emits light by being excited by the light emitting element 200 may be any material having the above-described main wavelength.

Thus, the wavelength conversion layer 400 is not in contact with the light emitting device 200, but is spaced apart from the light emitting device 200 by at least the thickness of the lens 300.

Further, the area of the wavelength conversion layer 400 is large enough to cover all the light fluxes of the light emitting element 200, and high-efficiency light conversion and light output can be obtained.

Accordingly, the light emitted from the first and second light emitting devices 210 and 220 and the light emitted from the second light emitting device 230 pass through the wavelength conversion layer 400 and are converted by the wavelength conversion layer 400 So that uniform light can be obtained at any angle.

Further, the light efficiency of the phosphor is reduced by heat, and since the phosphor is located apart from the light emitting device 200 which is a heat source, reduction in efficiency due to heat can be mitigated.

Meanwhile, the first wavelength band, which is the wavelength of the light emitted from the first light emitting devices 210 and 220, may be a blue band, and the second wavelength band, which is the wavelength of light emitted from the second light emitting device 230, may be a red band.

The light emitting layer that emits blue light may be a gallium nitride (GaN) -based material. The light emitting layer for emitting light in the red band may be GaP: ZnO, GaAsP-based or GaAlAs-based material.

At this time, the wavelength conversion layer 400 absorbs the emitted light of the light emitting device 200 to output light of a yellow band, and mixes with light of the first light emitting devices 210 and 220 of the blue band to realize white light .

On the other hand, the second light emitting device 230 of the red band can be used to enhance the color rendering property of the output light.

Compared with the red phosphor spectrum, the spectrum of the red light emitting device has a narrow half width, so that a long wavelength region which does not contribute greatly to the light output is small, so that high color rendering and high efficiency light output can be obtained.

As described above, the first and second light emitting devices 210 and 220 and the second light emitting device 230 may include a plurality of light emitting devices that respectively emit light of substantially the same wavelength band. In this case, The first and second light emitting devices 210 and 220 and the second light emitting device 230 may be positioned symmetrically with respect to each other. This is because color uniformity can be improved when the blue light and the red light are symmetrical to each other.

For example, the first and second light emitting devices 210 and 220 may be symmetrically positioned with respect to the second light emitting device 230.

1, the second light emitting device 230 is located along the line B on the center side of the package body 100, and the first light emitting devices 210 and 220 are disposed on the second light emitting device 230, respectively.

That is, the first light emitting devices 210 and 220 can be mounted on both sides at positions symmetrical with respect to the B line.

On the other hand, the wavelength of the main output of the wavelength conversion layer 400 can be 555 nm, which is excellent in visibility characteristics, and the main output peak can have a margin (± 15 nm) of 30 nm at 555 nm.

The light emitted from the first and second light emitting devices 210 and 220 may have a dominant wavelength ranging from 445 nm to 465 nm. More advantageously, the dominant wavelength in the first wavelength band, which is blue light, may be 450 nm.

On the other hand, the light emitted from the second light emitting device 230 may have a dominant wavelength of 580 nm to 630 nm. More advantageously, the dominant wavelength in the first wavelength band, which is red light, may be 615 nm.

At this time, the blue light may have a margin of ± 20 nm at 450 nm, and the red light may have a margin of ± 30 nm at 615 nm (± 15 nm).

In driving the light emitting device package 500, the first light emitting devices 210 and 220 and the second light emitting devices 230 are connected in parallel, and the respective light emitting devices 210, 220 and 230 ) Can be individually controlled.

The first light emitting devices 210 and 220 that emit light of the same color may be connected in series.

At this time, the color light emitted from the light emitting device package 500 may be significantly enhanced.

FIG. 3 is a perspective view of the light emitting device package, and FIG. 4 is an exploded perspective view of the light emitting device package.

As shown in the figure, the first and second light emitting devices 210 and 220 and the second light emitting device 230 positioned symmetrically with respect to each other can be extracted to the outside through the lens 300, forming a uniform light distribution.

The center axis of the lens 300 is coupled to the position having the greatest symmetry with the light emitting device 200. At this time, the lower side 310 of the lens 300 may be positioned by filling or contacting the light emitting device 200.

In addition, the outer surface of the lens 300 may exactly coincide with the groove 410 located inside the wavelength conversion layer 400.

The output light of the light emitting device 200 having passed through the lens 300 passes through the wavelength conversion layer 400 covering the lens 300 with a uniform thickness on the lens 300, And can be uniformly mixed with each other.

That is, as described above, a part of the blue light of the first light emitting devices 210 and 220 is converted into yellow light while passing through the wavelength conversion layer 400.

Since the first light emitting devices 210 and 220 are located symmetrically with respect to the adjacent surfaces of the lens 300 and the wavelength conversion layer 400, the first light emitting devices 210 and 220 do not exhibit a large deviation according to the position of the wavelength conversion layer 400 The blue light can be converted to a certain degree.

The red light of the second light emitting device 230 passes through the lens 300 and the wavelength conversion layer 400 as it is.

The blue light, the converted yellow light, and the red light are uniformly mixed with each other to produce high quality white light. At this time, the red light can significantly improve the color rendering property of the white light.

The white light thus produced can have a distribution of light distribution in the same state as in Fig. That is, the light distribution distribution by the light emitting device package 500 can form a Lambertian distribution.

The light emitting device package 500 can be used to manufacture an illumination device.

Hereinafter, a lighting apparatus using the light emitting device package 500 will be described with reference to FIGS. 6 and 7. FIG.

Fig. 6 is a perspective view showing an example of a lighting device, and Fig. 7 is an exploded perspective view showing an example of a lighting device.

6 and 7, the lighting apparatus includes a heat sink 10, a lens unit 20, a light emitting unit 30, a front unit (not shown), a case 50, and a power socket 60 .

The heat sink 10 may include an outer housing 11 having a hollow portion 14 and an inner housing 12 disposed in the hollow portion 14 and extending in the longitudinal direction, have.

The outer housing 11 may be formed of a material that is light in weight and high in thermal conductivity so as to radiate heat generated in the light emitting unit 30 to the outside during operation of the lighting apparatus, .

The hollow portion 14 is formed to penetrate along the longitudinal direction of the outer housing 11. For example, the hollow portion 14 may have a cylindrical shape. The inner housing 12, the front portion, the case 50, and the like may be inserted into the hollow portion 14.

The inner housing 12 is provided in the hollow portion of the outer housing 11. The inner housing 12 may be provided with a plurality of pins protruding toward the outer housing 11. These pins increase the surface area of the inner housing and increase the contact area between the inner housing and the outer housing to improve heat dissipation efficiency.

The heat generated in the light emitting unit 30 is transmitted to the inner housing 12 and the heat transmitted to the inner housing 12 is diverted to the outside through the outer housing 11 to dissipate heat.

The lens unit 20 is mounted on the outer housing 11. The lens unit 20 functions to guide light emitted from the light emitting unit 30 mounted on the outer housing 11 to the outside and may include at least one condenser lens.

The lens unit 20 is manufactured by molding a diffusing plate made of a resin such as polycarbonate or acrylic into a bulb shape so as to diffuse light emitted from the light emitting unit 30 to improve luminous efficiency .

The light emitting unit 30 includes a substrate 32 and a light emitting device package 500 mounted on the substrate 32. For example, the light emitting device package 500 may be mounted on a printed circuit board in a surface mount technology (SMT) manner.

The details of the light emitting device package 500 are the same as those described with reference to FIG. 1 and FIG. 2, and a detailed description thereof will be omitted.

On the other hand, the light emitting unit 30 can be mounted on the inner housing 12. That is, the substrate 32 of the light emitting unit 30 can be fastened to the inner housing 12. To this end, the lighting device may further include fastening means (not shown) that pass through the substrate 32 of the light emitting unit 30 and are fixed to the inner housing 12.

The fastening means may be a screw and the substrate 32 may be provided with a first fastening hole 31 through which the light emitting device package 500 is mounted and a rear fastening hole 31 through which the light emitting device package 500 is mounted, And a second fastening hole 13 may be provided at a position corresponding to the hole 31. [

On the other hand, the lighting device may further include a heat conductive pad 40 disposed between the light emitting unit 30 and the inner housing 12. When the heat conductive pad 40 is disposed between the light emitting unit 30 and the inner housing 12, the heat conductive pad 40 is provided with the first fastening hole 31 of the substrate 32 and the second fastening hole 31 of the inner housing 12, And a third fastening hole 41 may be provided at a position corresponding to the fastening hole 13. Accordingly, in this structure, the light emitting unit 30 and the heat conductive pad 40 can be fixed to the inner housing 12 by the fastening means described above.

The heat conduction pad 40 enhances the heat transfer performance between the light emitting unit 30 and the inner housing 12 and increases the contact area between the light emitting unit 30 and the inner housing 12, have.

(Not shown) is disposed in the hollow portion 14 of the outer housing 11 and is electrically connected to the light emitting unit 30. [ The electrical component part may include a circuit part that supplies power to the light emitting unit 30 and is electrically connected to the light emitting unit, and an insulating part that is filled in the space between the circuit part and the case to insulate the circuit part.

The circuit unit may include a driving circuit including a control unit capable of varying a current applied to each of the light emitting diodes. For example, this current variable can be performed by PWM control.

Meanwhile, the insulating portion filled in the space between the circuit portion and the case may be formed of silicon.

The case 50 is inserted into the hollow portion 14 of the outer housing 11 so as to surround the electric field portion. For example, the case 50 may be inserted into the hollow portion 14 of the outer housing 11 such that a portion of the region is disposed inside the inner housing 12. [

In addition, the case 50 and the hollow portion 14 of the outer housing 11 may be provided with structures for easy insertion of the case 50, respectively. A guide protrusion (not shown) may be provided on the outer circumferential surface of the case 50 and a guide protrusion (not shown) may be provided on the inner circumferential surface of the hollow portion 14 of the outer housing 11, A groove (not shown) may be provided.

The power socket 60 can be mounted on the case 50.

It should be noted that the embodiments of the present invention disclosed in the present specification and drawings are only illustrative of specific examples for the purpose of understanding and are not intended to limit the scope of the present invention. It will be apparent to those skilled in the art that other modifications based on the technical idea of the present invention are possible in addition to the embodiments disclosed herein.

100: package body 110: first region
120: second region 200: light emitting element
210, 220: first light emitting element 230: second light emitting element
300: lens 400: wavelength conversion layer
10: heat sink 11: outer housing
12: inner housing 20: lens unit
30: light emitting unit 31: substrate
40: heat conduction pad 50: case
60: Power socket

Claims (10)

In the light emitting device package,
A light emitting element disposed on the package body and including a first light emitting element for emitting light in a first wavelength band and a second light emitting element for emitting light in a second wavelength band;
A lens positioned on the light emitting element; And
And a wavelength conversion layer disposed on the lens. The light emitting device package according to claim 1, wherein the lens is a spherical lens. The light emitting device package according to claim 1, wherein the wavelength conversion layer has a constant thickness on the lens. The light emitting device package according to claim 1, wherein the first light emitting device and the second light emitting device each include a plurality of light emitting devices emitting light of substantially the same wavelength band. The light emitting device package according to claim 4, wherein the first light emitting device is symmetrically positioned with respect to the second light emitting device. The light emitting device package according to claim 5, wherein the second light emitting device is located at a center side of the package body, and the first light emitting device is located on both sides of the second light emitting device. The light emitting device package according to claim 1, wherein the wavelength conversion layer outputs light in a yellow band. The light emitting device package according to claim 1, wherein the first wavelength band is a blue band and the second wavelength band is a red band. The light emitting device according to claim 1, wherein the main wavelength of the first wavelength band is 450 nm, the main wavelength of the second wavelength band is 615 nm, and the wavelength of the main output of the wavelength conversion layer is 555 nm. package. A lighting device comprising the light emitting device package according to any one of claims 1 to 9.

Images