KR100883991B1 - Wide-band nature light emitting diode, method for manufacturing thereof - Google Patents

Abstract

Disclosed are a color conversion broadband light emitting diode capable of controlling color temperature, and a method of manufacturing the same. The light emitting diode includes a reflector, at least two LED chips, and a light emitting molding material. The reflector defines a space. The LED chips are arranged in a space defined by the reflector and emit light of different wavelengths, but emit light in response to a current regulated by a user. The light emitting molding material is formed on the LED chips, and phosphors excited by the light emitted from the LED chips are mixed. Accordingly, the multicolor implementation solves the low color rendering problem and the limited color temperature conversion problem by improving the color rendering property of a white or lighting bulb color LED having a limited narrow band characteristic and emitting visible light in a wide range, and thus a low power consumption lighting device. Can be provided.

Red Chip, Green Chip, Blue Chip, Light Emitting Diode, Phosphor, Color Temperature, Light Bulb

Description

Color conversion broadband light-emitting diode and its manufacturing method {WIDE-BAND NATURE LIGHT EMITTING DIODE, METHOD FOR MANUFACTURING THEREOF}

1 is a cross-sectional view illustrating a general light emitting diode.

FIG. 2 is a graph illustrating an emission spectrum of a white LED included in the general light emitting diode of FIG. 1.

3 is a cross-sectional view schematically illustrating a color conversion broadband light emitting diode according to an embodiment of the present invention.

4 is a plan view schematically illustrating the color conversion broadband LED shown in FIG. 3.

5A to 5F are cross-sectional views illustrating a method of manufacturing the color conversion broadband LED shown in FIG. 3.

6 is an emission spectrum of a color conversion broadband LED according to an embodiment of the present invention.

FIG. 7 is a plan view illustrating a light emitting diode module having the color conversion broadband light emitting diode shown in FIG. 3.

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

111: die pad portion 110: lead pad portion

130: reflector 140: the first LED chip

150: second LED chip 160, 170, 260: light emitting molding material

The present invention relates to a light emitting diode and a method for manufacturing the same, and more particularly, to a color conversion broadband light emitting diode having a color temperature control, improved manufacturing method thereof, and a light emitting module having the same.

In general, in order to realize a white light for lighting, three types of LED chips, red, green, and blue, are packaged in a single package, and each LED chip is individually controlled to realize various colors due to the variable brightness ratio. Because of the very narrow emission wavelength, color rendering is not good.

In addition, in order to realize a white light that is not controlled in color but has a relatively color rendering property, a short wavelength ultraviolet LED chip or a blue series LED chip having a phosphor having excellent excitation characteristics is applied to excite and emit a yellow wavelength region, which is a complementary color of the emission color. Phosphor is applied to LED chip together with molding resin to realize white color by mixing of blue emission wavelength and yellow emission wavelength. However, the short-wavelength blue LED chip, which is the excitation source, has a narrow-band emission characteristic, and the excitation emission characteristic of the yellow phosphor that emits excitation also emits a limited range of visible light, so that it does not realize emission in a wide wavelength region, thereby providing more color rendering properties. Not seeing.

In particular, in order to realize the light-emitting color characteristics of the light emitting diode for low light efficiency is provided by adding a pigment and a long wavelength phosphor that is not efficient to have a light emission characteristic of a wide range artificially.

1 is a cross-sectional view illustrating a general white light emitting diode.

Referring to FIG. 1, in the general light emitting diode 10, one LED chip 1 is disposed in a space defined by the reflector 5, and a phosphor having one spectrum in the space, for example, short wavelength excitation. The molding resin 9 including the phosphor 4 is filled. In Fig. 1, reference numeral 2 is a gold wire, 1 is a short wavelength LED chip, 3 is a die adhesive, 51 is an internal reflector, 8 is a solder lead, 7 is a die pad, and 71 is a lead pad.

As a result, the emission wavelengths of the two kinds of light emission sources emit only a part of the visible light. Accordingly, the present invention provides a light emitting device having poor color reproducibility, and a single wavelength LED chip as a light emitting source has a low intrinsic luminescence property according to the proportion of phosphors applied to excite light emission.

In particular, when implementing the light-emitting color of the light bulb, the intrinsic light-emitting characteristics of the LED chip is reduced, the color reproducibility is reduced in the short wavelength region because only the emission spectrum of the phosphor is emitted.

FIG. 2 is a graph showing an emission spectrum of a light emitting diode to which an LED chip and a single phosphor are provided in the general light emitting diode of FIG. 1.

Referring to FIG. 2, the LED chip emits light only at a narrow band wavelength, and the light emitting wavelength of the phosphor also emits light only at some two areas of visible light, for example, 450 nm and 580 nm. The two regions are divided into the intrinsic emission wavelength region of the LED chip and the emission wavelength region of the phosphor that is excited by the LED chip and emits light, thereby preventing the emission spectrum of all colors.

Accordingly, the technical problem of the present invention is to solve such a conventional problem, and an object of the present invention is to provide a color conversion broadband light emitting diode capable of improving color reproducibility by adjusting the color temperature by emitting visible light in a wide range.

Another object of the present invention is to provide a method of manufacturing the color conversion broadband light emitting diode.

Still another object of the present invention is to provide a light emitting diode module having the color conversion broadband light emitting diode.

In order to achieve the above object of the present invention, the color conversion broadband LED according to one embodiment includes a reflector, at least two LED chips, and a light emitting molding material. The reflector defines a space. The LED chips are disposed in a space defined by the reflector, and emit light having different wavelengths, and emit light in response to a current controlled by a user. The light emitting molding material is formed on the LED chips, and phosphors excited by a single light wavelength emitted from the LED chips are mixed.

In another aspect of the present invention, there is provided a method of manufacturing a color conversion broadband light emitting diode according to an embodiment, wherein a first short-wavelength first LED chip is formed by using a die adhesive on a first die pad exposed by a reflector. Die bonding and die bonding a second LED chip having a second wavelength to the second die pad exposed to the reflector, using the first LED chip, the first die pad, and the second LED chip. And electrically connecting each of the second die pads, and filling the first and second spaces with a light emitting molding material including a phosphor excited by the first light emission wavelength, by the reflector. .

According to another aspect of the present invention, there is provided a light emitting diode module including a board made of a conductive material having a PCB or a circuit, a reflector formed corresponding to an outermost region of the board, and a reflector. It includes a plurality of light emitting diodes arranged in a plurality of columns and a plurality of rows in the space defined by. The light emitting diode emits light of different wavelengths, and emits light in response to a current controlled by a user, and at least two LED chips, and are formed on the LED chips, and are formed by the light emitted from the LED chips. It includes a light emitting molding material in which the phosphor to be excited is mixed.

According to such a color conversion broadband light emitting diode, a manufacturing method thereof, and a light emitting module having the same, low color rendering is achieved by emitting visible light in a wide range by improving color rendering properties of a white or lighting bulb color LED having a narrow-band characteristic having a limited color. The problem and the limited color temperature conversion problem can be solved, and a low power consumption lighting device can be provided.

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

3 is a cross-sectional view schematically illustrating a color conversion broadband light emitting diode according to an embodiment of the present invention. 4 is a plan view schematically illustrating another example of FIG. 3.

3 and 4, a color conversion broadband light emitting diode 100 according to an embodiment includes a die pad part 111, a lead pad part 110, a solder lead 120, a reflector 130, and a first The LED chip 140, the second LED chip 150, the first light emitting molding material 160, and the second light emitting molding material 170 are included.

The reflector 130 defines a predetermined space while exposing a portion of the die pad part 111 and the lead pad part 110. The die pad part 111 and the lead pad part 110 are formed on the solder lead 120. The die pad part 111 and the lead pad part 110 are electrically connected to the first LED chip 140 or the second LED chip 150 through a gold wire WI.

For example, the die pad part 111 is die-bonded to each of the first and second LED chips 140 and 150, and is electrically connected to the first electrode of each of the LED chips. The lead pad unit 110 is electrically connected to a second electrode of each of the first and second LED chips 140 and 150.

The first and second LED chips 140 and 150 are disposed in a space defined by the reflector 130 and emit light having different wavelengths.

The first light emitting molding material 160 includes a first phosphor that is excited at a first light emission wavelength, and is filled in a space in which the first LED chip 140 is disposed. The second light emitting molding material 170 includes a molding material that is the same as a transparent or first phosphor that is not excited by the second light emitting wavelength and is filled in a space in which the second LED chip 150 is disposed.

The first and second LED chips 140 and 150 emit light in response to a current adjusted by a user. For example, when the applied current is relatively large, light of relatively high luminance is emitted, and when the applied current is relatively small, light of relatively low luminance is emitted.

In one embodiment, the second LED chips 150 have a wavelength that is 130 nm or more different from the wavelength of light emitted from the first LED chip 140. For example, when the first LED chip 140 emits light for exciting the phosphor, the second LED chip 150 emits light in a section other than the excitation wavelength of the phosphor. Here, the second LED chip 150 emits light in response to the current adjusted by the user. In one embodiment, the second LED chip 150 emits light of 585 nm to 595 nm. In another embodiment, the second LED chip 150 emits light of 600 nm to 650 nm.

The phosphor may have a property of being excited in a region of 40 nm to 80 nm or more than light emitted from the first LED chip 140 emitting short wavelength light.

In one embodiment, the phosphor is excited in an area of 40 nm to 80 nm or more than the light emitted from the first LED chip 140 that emits short wavelength light among the first and second LED chips 140 and 150. The first phosphor and the second phosphor having an emission wavelength in the region of 600 nm to 660 nm can be mixed and used.

In one embodiment, the interval between peak values of the light emitted from the first and second LED chips 140 and 150 is 130 nm or more.

In FIG. 3, the reflector 130 has a shape that independently wraps the first and second LED chips 140 and 150, respectively. Those skilled in the art may deform the reflector 130 to have a shape that integrally surrounds the first and second LED chips 140 and 150. For example, the reflector may be applied to the shape surrounding the rectangular light emitting diode.

In FIG. 3, two LED chips form one unit, but a person skilled in the art may configure one unit. Of course, it is also possible to arrange a plurality of units for use as a lighting device.

5A to 5F are cross-sectional views illustrating a method of manufacturing the color conversion broadband LED shown in FIG. 3.

5A and 5B, the first short wavelength LED chip 140 is die-bonded using a die adhesive on a die pad surface having a reflector formed around a first die pad, and a die is formed on a reflector formed around a second die pad. An adhesive is used to die bond one or more LED chips 150 having a second wavelength.

In one embodiment, the second LED chips 150 are selected to be set to 130 nm or more than the wavelength of the first LED chip exhibiting an excitation characteristic. In one embodiment, the second LED chips are configured such that one kind of light emitting diodes of 585 to 595 nm and one kind of 600 to 650 nm can be individually die-bonded.

Referring to FIG. 5C, the first and second LED chips 140 and 150 are wire bonded with gold wires WI for electrical connection.

Referring to FIG. 5D, a first phosphor having a property of being excited at a first emission wavelength is mixed with a molding resin in a predetermined ratio to produce a desired emission color and wavelength spectrum, and the first LED chip 140 is formed through a deforming operation. Is disposed and filled in the space defined by the reflector.

Referring to FIG. 5E, the second LED chip 150 which is not excited to the first phosphor is disposed so that the transparent molding material does not contain the phosphor in the space defined by the reflector or the molding resin same as the first phosphor. Is filled by deforming.

Referring to FIG. 5F, after curing by heat or UV light on the resultant of FIG. 5E, a light emitting diode capable of color adjustment and high color rendering is completed. Here, color rendering is a phenomenon in which lighting affects the color of an object. In other words, the color is different depending on which light source the object of the same chromaticity is viewed under illumination. In order to solve the color rendering problem, a conventional fluorescent lamp is used, or a lamp in which a fluorescent lamp and an incandescent lamp or other kinds of fluorescent lamps are used. However, in the present invention, the yellow-based light emitted by the phosphor and the blue-based light emitted from the first LED chip 140 and the yellow or red light emitted from the second LED chip 150 are mixed. Since the white light is emitted, the color rendering property can be improved.

In addition, since a variable current is applied to a plurality of LED chips individually according to a user's adjustment, color temperature adjustment can be easily achieved.

In the above, it was described that each of the LED chips is filled with a different phosphor or the same phosphor in the space defined by each reflector. However, those skilled in the art may mix and form different phosphors on each of the LED chips. Specifically, an LED chip having a short wavelength having good excitation efficiency of the first phosphor is die-bonded to a lead frame in which a reflector is configured around a die pad on which the LED chip is seated, and a second excitation emission wavelength is formed on a plurality of pads. After die-bonding LED chips having different long wavelengths, a certain ratio of phosphors exhibiting excitation characteristics at the first wavelength is mixed with the molding resin, followed by a deforming process, and then applied at a time onto a plurality of LED chips to emit light at different wavelengths. A light emitting combination of an LED chip and a phosphor having excitation characteristics at one wavelength may provide a color conversion broadband light emitting diode emitting light in a wide wavelength region.

As described above, according to the present invention, a color conversion broadband light emitting diode packaged in a plurality of narrowband wavelengths emitted by phosphors other than the inherent narrowband wavelengths emitted from the LED chip so that light having various emission spectra is emitted. To prepare. Accordingly, in the output of the final light emitting unit, a high color rendering can be achieved by complementing each other through a combination of the wavelength of the LED chip and the wavelength of the phosphor that is excited by the natural wavelength and emits light. In addition, phosphors and other long-wavelength LED chips that are not excited can be controlled individually to achieve various color temperatures.

6 is a light emission spectrum of a color conversion broadband LED according to an embodiment of the present invention. In particular, the emission spectra of the short wavelength LEDs exhibiting two kinds of light emission characteristics and the phosphor having the characteristics of being excited by the above-mentioned short wavelengths and emitting light are shown.

Referring to FIG. 6, LED chips showing two types of light emission characteristics and two or more types of phosphors showing different light emission characteristics are mixed at a predetermined ratio and simultaneously filled to fill the LED chips in common, thereby obtaining two wavelength peak values. One curves are plotted.

FIG. 7 is a plan view illustrating a light emitting diode module having the color conversion broadband light emitting diode shown in FIG. 3. In comparison with FIG. 3, the same components are given the same reference numerals, and detailed description thereof will be omitted.

Referring to FIG. 7, the light emitting diode module 200 according to the present invention includes a plurality of color conversion broadband LEDs 100 arranged in a plurality of columns and a plurality of rows. In FIG. 7, reference numeral 210 is a board made of a conductive material that can be configured as a PCB or a circuit, and reference numeral 220 is a reflector. The reflector 220 is formed corresponding to the outermost region of the board 210.

In FIG. 7, two LED chips emitting light having different wavelengths are arranged in a unit region, but three or more LED chips may be arranged having light having different wavelengths.

As described above, the wide wavelength wavelength light emitting diode of the present invention is capable of improving the color rendering problem of a general narrowband multicolor light emitting device, improving the luminous efficiency of phosphor, and applying a individually controllable package structure to minimize the color By simplifying the light emitting diode manufacturing process at the cost and realizing simultaneous broadband, it is possible to supply products with high color rendering and low manufacturing cost by maximizing production yield and yield, which is a big change in the lighting replacement market that was not activated due to the high price and low color rendering. Can be imported.

Although described above with reference to the embodiments, those skilled in the art can be variously modified and changed within the scope of the present invention without departing from the spirit and scope of the invention described in the claims below. I can understand.

Claims (21)

In the color conversion broadband light emitting diode comprising a substrate, A first LED chip mounted on the substrate and emitting light having a first wavelength; A second LED chip mounted on the substrate and emitting light having a second wavelength; A reflector extending to an upper portion of the substrate and having a space in which the first LED chip and the second LED chip are mounted; And A light emitting molding material filled in the space and containing a first phosphor that is excited by light emitted from the first LED chip and emits light having a third wavelength, The first wavelength of light is blue light, the second wavelength has a peak spacing of 130 nm or more, the third wavelength has a peak spacing of 40 nm to 80 nm with the first wavelength, Each of the first LED chip and the second LED chip, the color conversion broadband light emitting diode, characterized in that the brightness can be changed to change the color temperature of the light emitting diode. The method of claim 1, The second LED chip is at least one LED chip that emits light of different wavelengths, The second wavelength is at least one of 585nm to 595nm, or 600nm to 650nm color conversion broadband light emitting diode, characterized in that. The method of claim 2, The light emitting molding material further comprises a second phosphor that emits light having a wavelength of 600nm to 660nm color conversion broadband light emitting diodes. The substrate according to any one of claims 1 to 3, wherein Die pads each of which the first LED chip and the second LED chip are die-bonded and electrically connected to a first electrode of each of the first LED chip and the second LED chip; and A lead pad part electrically connected to a second electrode provided in each of the first LED chip and the second LED chip; Each of the first LED chip and the second LED chip is a color conversion broadband light emitting diode, characterized in that the brightness is varied by controlling the intensity of the current applied through at least one of the die pad unit or the lead pad unit. The method of claim 4, wherein And the reflector independently surrounds each of the first and second LED chips. The method of claim 5, Each of the first LED chip and the second LED chip constitutes one unit, The unit is arranged in a plurality of columns and a plurality of rows, And the reflector is formed to surround the units. Die bonding a first LED chip that emits light of a first wavelength using a die adhesive on a first die pad exposed to a space formed by the reflector, and using a die adhesive on a second die pad exposed to the space Die-bonding a second LED chip that emits two wavelengths of light; Electrically connecting the first LED chip and the first die pad to each of the second LED chip and the second die pad; And And filling the space with a light emitting molding material including a first phosphor that is excited by the light of the first wavelength and emits light of the third wavelength. The first wavelength of light is blue light, the second wavelength has a peak spacing of 130 nm or more, the third wavelength has a peak spacing of 40 nm to 80 nm with the first wavelength, And each of the first LED chip and the second LED chip can control the intensity of a current applied to change the brightness of the light emitting diode so as to change the color temperature of the light emitting diode. The method of claim 7, wherein The space includes a first space in which a first LED chip is die bonded and a second space in which a second LED chip is die bonded. And curing the light emitting molding material filled in the first space and the second space through heat or UV curing. The method of claim 8, The second LED chip is at least one LED chip that emits light of different wavelengths, The second wavelength is at least one of 585nm to 595nm, or 600nm to 650nm manufacturing method of the color conversion broadband light emitting diode. The method of claim 9, The light emitting molding material further comprises a second phosphor that emits light having a wavelength of 600 nm to 660 nm. delete delete delete delete delete delete delete delete delete delete delete

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