KR20070098195A - Light emitting diode - Google Patents

Abstract

A light emitting diode is provided to emit the light of uniform color by distributing the fluorescent substance uniformly to a position higher than a horizontal plane of an end of a reflecting part. A light emitting diode comprises a first lead terminal(20), and a second lead terminal(30) spaced with predetermined interval for the first lead terminal(20). A groove is formed in a predetermined region of the first lead terminal(20), and a reflecting part(40) is formed in a lateral side wall of the groove. A light emitting diode chip(10) is mounted on the reflecting part(40) of the first lead terminal(20), and is connected with the second lead terminal(30) electrically using a wire(50). A molding part(60) sealing the reflecting part(40) contains the fluorescent substance for implementing a desired color. The fluorescent substance is distributed uniformly to a position higher than a horizontal plane of an end of the reflecting part(40).

Description

Light emitting diodes

1 and 2 are cross-sectional views showing a conventional light emitting diode.

3 and 4 are cross-sectional views showing a first embodiment of a light emitting diode according to the present invention;

5 is a sectional view showing a second embodiment of a light emitting diode according to the present invention;

6 is a sectional view showing a third embodiment of a light emitting diode according to the present invention;

<Explanation of symbols for main parts of the drawings>

10, 110, 210: light emitting diode chip

40, 140, 250: reflector 60, 160, 160: molding part

70, 170, 270: phosphor

The present invention relates to a light emitting diode, and more particularly, to a light emitting diode capable of preventing light loss due to the phosphor of the light emitting diode to increase light efficiency and to emit uniform white light.

A light emitting diode (LED) refers to a device that makes a small number of carriers (electrons or holes) injected using a pn junction structure of a semiconductor and emits a predetermined light by recombination thereof. It can be installed in a long, narrow space, and also provides vibration resistance. Recently, in addition to single color components, for example, red, blue, or green light emitting diodes, white light emitting diodes have been released, and demand for them is rapidly increasing.

The light emitting diode may implement white light using a single chip or multiple chips. In the case of a single chip, white light is realized by combining a light emitting diode chip of a compound semiconductor and a phosphor. That is, the phosphor is disposed on the light emitting diode chip so that a part of the first light emission of the light emitting diode chip and the secondary light emission wavelength-converted by the phosphor are mixed to realize white. White light emitting diodes of this structure are widely used because of their low cost and very simple in principle and structure.

1 and 2 are cross-sectional views showing a conventional light emitting diode.

Referring to the drawings, the light emitting diode includes a first lead terminal 2 having a reflecting portion 4 formed at a tip thereof, and a second lead terminal 3 spaced apart from the first lead terminal 2 by a predetermined distance. The light emitting diode chip 1 is mounted in the reflection part 4 of the first lead terminal 2 and electrically connected to the second lead terminal 3 through a wire 5. The light emitting diode also includes a phosphor 7 for wavelength converting light from the light emitting diode chip 1 to achieve the desired color.

As shown in FIG. 1, the light emitting diode includes an outer peripheral molding part 6 formed at a front end of the lead terminals 2 and 3 by using a molding mold, and the phosphor 7 has an outer peripheral molding part ( 6) can be formed evenly distributed throughout. In this case, a large amount of phosphors 7 should be included for distribution in the outer molding part 6, which may cause a loss of light, which may cause a decrease in luminous efficiency. In addition, the outer molding part 6 is formed by mixing the phosphor 7 with a liquid epoxy resin, and due to the difference in specific gravity of the resin and the phosphor 7, it is difficult to uniformly distribute the phosphor 7 in the outer molding part 6. . That is, there is a problem that the implementation of uniform white light is difficult.

In addition, as shown in FIG. 2, the light emitting diode includes the molding part 8 filled in the reflecting part 4 including the phosphor 7 and an outer molding part formed at the front end portions of the lead terminals 2 and 3. And (9). In this case, since the phosphor 7 is mostly concentrated around the light emitting diode chip 1 inside the reflecting portion 4 of the lead terminals 2 and 3 having a very narrow area, the light emitted from the light emitting diode chip 1 As the transmittance of light is reduced, not only the white light required by the consumer is realized but also the brightness of the light emitting diode itself is very poor. In addition, the light emitted from the side of the light emitting diode chip 1 and reflected by the reflector 4 reacts with the phosphor 7 relatively to the light emitted by going straight to the top surface of the light emitting diode chip 1. Since there are many, it is difficult to implement a uniform white light.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a light emitting diode capable of preventing light loss due to the phosphor of the light emitting diode, thereby increasing the light efficiency and allowing uniform white light emission.

The present invention includes a body having a groove formed in the upper portion, a light emitting diode chip mounted on a lower surface of the groove portion, and a molding portion encapsulating the groove and containing a phosphor, in order to achieve the above object. Provided is a light emitting diode which is distributed at a position higher than a horizontal plane. The sidewall surface of the groove portion may have a predetermined slope, and the body may be any one of a lead terminal, a substrate, and a heat sink.

The light emitting diode chip may include a light emitting diode chip emitting blue light, and the phosphor may include at least one phosphor having green, yellow, or red light emission characteristics. The light emitting diode chip may include a light emitting diode chip that emits UV light, and the phosphor may include a phosphor having red, green, and blue light emitting characteristics.

Hereinafter, with reference to the accompanying drawings will be described in more detail with respect to the present invention. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various forms, and only the embodiments are intended to complete the disclosure of the present invention, and to those skilled in the art to fully understand the scope of the invention. It is provided to inform you. Like numbers refer to like elements in the figures.

3 shows a first embodiment of a light emitting diode according to the invention.

Referring to FIG. 3, the light emitting diode includes a first lead terminal 20, a second lead terminal 30 spaced apart from the first lead terminal 20 by a predetermined distance, and the first lead terminal 20. ) Includes a reflector 40 having a groove formed in a predetermined area and having a predetermined slope on the sidewall surface of the groove. The LED chip 10 is mounted on the reflector 40 of the first lead terminal 20 and is electrically connected to the second lead terminal 30 through a wire 50. In addition, the light emitting diode includes a molding part 60 encapsulating the reflecting part 40 and an outer molding part 80 formed at the front end portions of the lead terminals 20 and 30. Here, the molding part 60 includes a phosphor 70 for wavelength converting light from the light emitting diode chip 10 in order to achieve a desired color, and the phosphor 70 is formed at a horizontal plane at the tip of the reflector 40. It is characterized in that it is uniformly distributed in a high position.

The LED chip 10 and the phosphor 70 may use various types to obtain a desired color. For white light emission, a blue light emitting diode chip emitting a wavelength of 430 to 480 nm is mounted, and a phosphor capable of generating yellow light using blue light as an excitation source is used. In addition, for white light emission, a mixture of UV light emitting diode chips emitting wavelengths of 350 nm to 450 nm and mounting phosphors emitting red, blue and green light may be used. In addition, the number of the light emitting diode chips 10 may be one, or may be configured in plural as desired.

As shown in the drawing, the first lead terminal 20 on which the LED chip 10 is mounted includes a reflector 40, and the sidewalls of the reflector 40 have a predetermined slope. This is preferable in order to maximize reflection of light emitted from the LED chip 10 and to increase luminous efficiency. The LED chip 10 is mounted on a lower plane of the reflector 40. As shown in the embodiment, the LED chip 10 is directly mounted on the first lead terminal 20 using the LED chip 10 having positive and negative electrodes on the upper and lower planes of the LED chip 10 to be electrically connected. After the second wire terminal 30 is electrically connected to the second lead terminal 30 through a single wire 50, the light emitting diode chip 10 having a positive electrode and a negative electrode in the upper plane of the light emitting diode chip 10 is used. The wire 50 may be electrically connected to the first lead terminal 20 and the second lead terminal 30, respectively.

The molding part 60 is formed by injecting a mixture of the phosphor 70 and a liquid epoxy or silicone resin into the reflecting part 40. In this case, first, the liquid epoxy or silicone resin is injected, and then the phosphor 70 is gradually mixed and injected, so that the phosphor 70 may be formed to be distributed at a position higher than the horizontal plane of the tip of the reflector 40. Alternatively, the phosphor 70 is doped so that the mixture of the liquid epoxy or silicone resin is formed at a position higher than the horizontal plane of the front end of the reflector 40, and then the lead terminals 20 and 30 are inverted and cured. ) May be formed to be distributed at a position higher than the horizontal plane of the tip of the reflector 40.

In addition, the molding part 60 may be formed by double molding as shown in FIG. 4. That is, after injecting a liquid epoxy or silicone resin into the reflecting portion 40 to the front end surface of the reflecting portion 40 to form the first molding portion 61, the upper portion of the first molding portion 61 A mixture of the resin and the phosphor may be doped to cover the reflector 40 to form the second molding part 62 in which the phosphor 70 is uniformly distributed. For this reason, the phosphor 70 may be formed to be distributed at a position higher than the horizontal plane of the tip of the reflector 40.

The outer peripheral molding part 80 is filled with a liquid epoxy or silicone resin in a molding mold, and then the lead terminal 20 in which the light emitting diode chip 10 is mounted and the reflecting part 40 is sealed by the molding part 60. , 30) may be formed by dipping in a mold for containing the resin and heat curing for a predetermined time.

Of course, the method of manufacturing the molding part and the outer molding part is not limited to the above description, and may be formed by various processes and manufacturing methods.

The front end of the LED chip 10 and the first and second lead terminals 20 and 30 are sealed by the molding part 60 and the outer molding part 80, and the first and second lead terminals exposed below. An external current may be applied to the LED chip 10 by electrically connecting the 20 and 30 and an external current input terminal.

In the light emitting diode of the present embodiment, primary light is emitted from a light emitting diode chip, and the primary light is emitted and directed toward the upper portion of the reflector without reflection of light due to a conventional phosphor or without path obstruction in the reflector. do. The primary light emitted to the upper part of the reflector is wavelength-converted by a phosphor uniformly distributed at a position higher than the horizontal plane of the tip of the reflector, and a part of the primary light and the secondary light wavelength-converted by the phosphor are mixed to a desired color, In particular, white light can be realized.

Conventional lamp-type light emitting diodes are filled with a mixture of resin and phosphor in a small area of the reflector to concentrate a large amount of phosphor around the light emitting diode chip, so that the light emitted from the light emitting diode chip is concentrated on the phosphor particles in the reflector. The light is absorbed or emitted by the phosphor and canceled with each other and then lost. However, in the light emitting diode of the present embodiment, the phosphor is uniformly distributed in a position higher than the horizontal plane of the tip of the reflector, thereby reducing the loss of light emitted from the light emitting diode chip and increasing the light transmittance.

In addition, conventionally, there is a problem that color uniformity is deteriorated due to a difference in wavelength conversion degree of light emitted from side and top surfaces of a light emitting diode. However, the light emitting diode according to the present embodiment may emit light having a wavelength converted by the phosphor uniformly distributed after being emitted to the upper portion of the reflector regardless of the direction of light emitted from the light emitting diode chip, thereby realizing a uniform color of light.

The present invention is not limited to the above-described lamp type light emitting diode, but can be applied to products having various structures including light emitting diode chips and phosphors.

Duplicate description will be omitted for the various embodiments described below.

5 shows a second embodiment of a light emitting diode according to the invention.

Referring to FIG. 5, a light emitting diode may be formed on a substrate 100 having a groove, that is, a reflector 140, electrodes 120 and 130 formed on the substrate 100, and a lower surface of the reflector 140. The mounted LED chip 110 and the molding part 160 encapsulating the reflective part 140 are included. Here, the molding unit 160 includes a phosphor 170 for wavelength converting light from the light emitting diode chip 110 in order to achieve a desired color, and the phosphor 170 may be formed in a horizontal plane at the tip of the reflector 140. It is characterized in that it is uniformly distributed in a high position.

The reflector 140 may have a predetermined slope formed on the sidewall thereof to maximize reflection of light emitted from the LED chip 110 and increase luminous efficiency.

The electrodes 120 and 130 include first and second electrodes 120 and 130 for connecting to the positive terminal and the negative terminal of the LED chip 110 on the substrate 100. The first and second electrodes 120 and 130 may be formed through a printing technique. The first and second electrodes 120 and 130 are formed of a metal material including copper or aluminum having excellent conductivity, and the first electrode 120 and the second electrode 130 are formed to be electrically disconnected.

The light emitting diode chip 110 is mounted on the first electrode 120 formed in the lower plane of the reflector, and is electrically connected to the second electrode 130 through the wire 150. Although the embodiment is directly mounted on the electrodes 120 and 130 using the light emitting diode chip 110 having the positive electrode and the negative electrode on the upper and lower planes of the light emitting diode chip 110 as shown, Two wires 150 when formed on the substrate 100 without being mounted on the electrodes 120 and 130 using the light emitting diode chip 110 having a positive electrode and a negative electrode in the upper plane of the chip 110. The first electrode 120 or the second electrode 130 may be connected to each other.

The molding part 160 is formed by injecting a mixture of the phosphor 170 and a liquid epoxy or silicone resin into the reflector 140. In this case, the phosphor 170 is formed to be uniformly distributed at a position higher than the horizontal plane of the tip of the reflector 140. In addition, as mentioned above, the first molding part made of resin may be formed in the reflecting part 140, and then the second molding part made of a mixture of resin and phosphor may be formed thereon.

In addition, although not shown, it may further include an outer molding part (not shown) surrounding the molding part 160 to protect the molding part 160 and the electrodes 120 and 130.

The molding unit 160 including the phosphor 170 encapsulates the LED chip 110, and predetermined regions of the first and second electrodes 120 and 130 are exposed to the outside of the molding unit 160. Through this, the first and second electrodes 120 and 130 may be electrically connected to the external current input terminal to apply an external current to the LED chip 110.

In the present embodiment, a groove is formed in a predetermined region of the substrate on which the LED chip is mounted, the LED chip is mounted on a lower plane thereof, and a molding part is formed in the groove, but the present invention is not limited thereto. After mounting the chip, a reflector may be formed to surround the LED chip, thereby forming a molding part in the reflector.

In the light emitting diode of the present embodiment, the phosphor is uniformly distributed in a position higher than the horizontal plane of the tip of the reflector, thereby reducing the loss of light emitted from the light emitting diode chip and realizing uniform color light.

6 shows a third embodiment of a light emitting diode according to the invention.

Referring to FIG. 6, a light emitting diode includes a housing 200 having electrodes 220 and 230 formed at both sides thereof, and including a through hole, and a groove, that is, a reflecting part 250, mounted in the through hole of the housing 200. Is a heat sink 240, a light emitting diode chip 210 mounted on the reflector 250 of the heat sink 240, and a molding unit 260 encapsulating the reflector 250. Here, the molding part 260 includes a phosphor 270 that wavelength-converts light from the light emitting diode chip 210 to implement a desired color, and the phosphor 270 is a horizontal plane at the front end of the reflector 250. It is characterized in that it is uniformly distributed in a higher position.

A predetermined slope is formed on the sidewall surface of the reflector 250 to maximize reflection of light emitted from the LED chip 210 and increase luminous efficiency.

The housing 200 uses PPA, LCP or thermally conductive resin. As the heat sink 240 mounted in the through hole of the housing 200, a metal material having excellent thermal conductivity and electrical conductivity may be used, or a resin having excellent thermal conductivity may be used. By using a material having excellent thermal conductivity, heat emitted from the light emitting diode chip 210 may be effectively released and thermal burden may be reduced. In addition, the heat dissipation effect can be further enhanced by additionally combining an external heat sink.

The molding part 260 is formed by injecting a mixture of the phosphor 270 and a liquid epoxy or silicone resin into the reflecting part 250. In this case, the phosphor 270 is formed to be uniformly distributed at a position higher than the horizontal plane of the tip of the reflector 250. In addition, as mentioned above, the first molding part made of resin may be formed in the reflecting part 250, and then the second molding part made of a mixture of resin and phosphor may be formed thereon.

In addition, the light emitting diode of the present exemplary embodiment may have an outer circumference for protecting the molding part 260 and the wires 290 and 300 and the electrodes 220 and 230 for electrical connection of the LED chip 210. The molding unit 280 may further include.

In the light emitting diode of the present embodiment, the phosphor is uniformly distributed in a position higher than the horizontal plane of the tip of the reflector, thereby reducing loss of light emitted from the light emitting diode chip and realizing uniform color light.

As mentioned above, although this invention was demonstrated in detail using the preferable Example, the scope of the present invention is not limited to a specific Example and should be interpreted by the attached Claim. In addition, those skilled in the art should understand that many modifications and variations are possible without departing from the scope of the present invention.

In the light emitting diode of the present invention, the phosphor contained in the molding part is uniformly distributed at a position higher than the horizontal plane of the tip of the reflector, thereby preventing light loss due to the phosphor, thereby increasing light efficiency. In addition, there is an advantage that can emit light of a uniform color, in particular white light.

Claims (5)

A body having a groove formed at an upper portion thereof; A light emitting diode chip mounted on a lower surface of the groove; And A molding part encapsulating the groove part and containing a phosphor; The phosphor is distributed in a position higher than the horizontal plane of the tip of the groove portion. The method according to claim 1, The side wall surface of the groove portion is a light emitting diode, characterized in that a predetermined slope is formed. The method according to claim 1 or 2, The body is a light emitting diode, characterized in that any one of a lead terminal, a substrate or a heat sink. The method according to claim 1 or 2, The light emitting diode chip includes a light emitting diode chip emitting blue light, and the phosphor includes at least one phosphor having green, yellow, or red light emitting characteristics. The method according to claim 1 or 2, The light emitting diode chip includes a light emitting diode chip that emits UV light, and the phosphor comprises a phosphor having red, green, and blue light emitting characteristics.

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