JP2007035882A - Led illuminator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an LED illuminator capable of reducing costs as compared with before. <P>SOLUTION: The LED illuminator comprises an LED chip 10 for radiating blue light; a circuit board 50 to which the LED chip 10 is packaged; and a lens 60 sealed to the circuit board 50 in a shape for surrounding the LED chip 10 at an area to the circuit board 50. In the lens 60, a color conversion section 40 is integrated, where the color conversion section 40 comprises a transparent material and a yellow fluorescent material that is excited by light radiated from the LED chip 10 and radiates light with a color differing from the luminous color of the LED chip 10. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an LED lighting device using an LED chip (light emitting diode chip).

  Conventionally, an LED chip and a fluorescent material that is excited by light emitted from the LED chip and emits light of a different emission color from the LED chip are combined with a light emitting color different from that of the LED chip. Research and development of light-emitting devices that emit light are performed in various places (for example, Patent Document 1). In addition, as this kind of light emitting device, for example, a white light emitting device (generally a white LED) that obtains white light (white light emission spectrum) by combining an LED chip that emits blue light or ultraviolet light and a phosphor. Has been commercialized).

  In Patent Document 1, for example, as shown in FIG. 5, an LED chip 10 ′ that emits blue light and a mounting substrate 20 ′ on which the LED chip 10 ′ is mounted, A mounting substrate 20 ′ in which a housing recess 20a ′ for housing the chip 10 ′ is formed, a sealing portion 30 ′ made of a sealing resin filled in the housing recess 20a ′ and sealing the LED chip 10 ′, and yellow There is disclosed a light emitting device 1 ′ that is a molded product obtained by molding a phosphor together with a resin and includes a sheet-like color conversion member 140 ′ fixed to a mounting substrate 20 ′ so as to cover a sealing portion 30 ′. . In the light emitting device 1 ′ of FIG. 5, a package is configured by the mounting substrate 20 ′ and the color conversion member 140 ′.

By the way, as an LED lighting device using the light emitting device 1 ′ as shown in FIG. 5, for example, as shown in FIG. 6, the light emitting device 1 ′ is mounted on the circuit board 50 ′ and emitted from the light emitting device 1 ′. A lens 60 ′ for controlling the light distribution of the emitted light is arranged on the light emitting device 1 ′ so that the optical axes thereof coincide with each other.
JP 2003-46133 A

  By the way, in the LED illumination device shown in FIG. 6, since the white illumination color is obtained by the light emitting device 1 ′ in which the LED chip 10 ′ is packaged, the LED illumination device having a blue illumination color is developed as another type. In order to achieve this, it is necessary to prepare a light emitting device in which the LED chip 10 'is packaged without using the color conversion member 140', and light emitting devices having different illumination colors for white and blue types are required. There was a problem that the cost was high.

  This invention is made | formed in view of the said reason, The objective is to provide the LED illuminating device which can aim at cost reduction compared with the past.

  The invention according to claim 1 is an LED chip that emits visible light, a circuit board on which the LED chip is mounted, and a lens that controls light distribution of at least light emitted from the LED chip. A lens that is sealed to a circuit board so as to surround the LED chip, and the lens is excited by the light emitted from the transparent material and the LED chip and emits light of a color different from the emission color of the LED chip The color conversion part comprised with material is integrated, It is characterized by the above-mentioned.

  According to the present invention, the lens is sealed to the circuit board so as to surround the LED chip with the circuit board, and is excited by the light emitted from the transparent material and the LED chip and the light emission color of the LED chip is Since the color conversion unit composed of fluorescent materials that emit light of different colors is integrated with the lens, the package of the LED chip is composed of the circuit board and the lens. There is no need to prepare them, and the cost can be reduced. By preparing a lens with an integrated color converter and a lens with no integrated color converter, the light and color emitted from the LED chip are prepared. An LED illumination device that uses mixed color light with light emitted from the fluorescent material of the conversion unit as illumination light, and an LED illumination device that uses light emitted from the LED chip as illumination light. We are able to share the LED chips do not, thereby the cost.

  According to a second aspect of the present invention, in the first aspect of the invention, the color conversion unit is integrated with the lens by being molded simultaneously with the lens.

  According to this invention, the number of parts can be reduced compared to the case where the color conversion unit and the lens are separate parts, and the management cost of the parts can be reduced.

  The invention according to claim 3 is characterized in that the color conversion section is integrated with the lens by being bonded to the lens.

  According to the present invention, the lens can be shared regardless of the desired illumination color, and the cost can be reduced.

  The invention of claim 1 has an effect that the cost can be reduced as compared with the prior art.

(Embodiment 1)
As shown in FIG. 1, the LED lighting device according to the present embodiment includes an LED chip 10 that emits visible light, a circuit board 50 on which the LED chip 10 is mounted, a transparent material, and light emitted from the LED chip 10. A color conversion unit 40 composed of a fluorescent material that is excited and emits light of a color different from the emission color of the LED chip 10, and the arrangement of the light emitted from the LED chip 10 and the light emitted from the fluorescent material And a lens 60 for controlling light.

  The circuit board 50 employs a metal board on which a pair of conductor patterns 53 and 53 are formed on the metal plate 51 via an insulating layer 52, and heat generated in the LED chip 10 is transferred to the metal board 51. It is supposed to be. In addition, although Cu is employ | adopted as a material of the metal plate 51, what is necessary is just a metal material with comparatively high heat conductivity, and not only Cu but Al etc. may be employ | adopted.

  The LED chip 10 is a GaN-based blue LED chip that emits blue light, and is a conductive substrate made of an n-type SiC substrate that has a lattice constant and a crystal structure close to GaN as a crystal growth substrate and has conductivity compared to a sapphire substrate. The light-emitting portion 12 is formed of a GaN-based compound semiconductor material on the main surface side of the conductive substrate 11 and has a laminated structure portion having, for example, a double hetero structure. ), A cathode electrode (n electrode) which is a cathode side electrode (not shown) is formed on the back surface of the conductive substrate 11, and is shown on the surface of the light emitting unit 12 (the outermost surface on the main surface side of the conductive substrate 11). An anode electrode (p electrode) which is an electrode on the anode side that is not to be formed is formed. In short, the LED chip 10 has an anode electrode formed on one surface side and a cathode electrode formed on the other surface side. The cathode electrode and the anode electrode are composed of a laminated film of a Ni film and an Au film, but the material of the cathode electrode and the anode electrode is not particularly limited, and a material capable of obtaining good ohmic characteristics For example, Al or the like may be employed. In the present embodiment, the light emitting unit 12 of the LED chip 10 is mounted on the metal plate 51 so as to be on the side farther from the metal plate 51 than the conductive substrate 11. You may make it mount in the metal plate 51 so that it may become the side near the metal plate 51 rather than the electroconductive board | substrate 11. FIG.

  The LED chip 10 is formed on the metal plate 51 in the shape of a rectangular plate having a size larger than the chip size of the LED chip 10, and the LED chip 10 is caused by a difference in linear expansion coefficient between the LED chip 10 and the metal plate 51. It is mounted via a submount member 80 that relieves stress acting on the chip 10. The submount member 80 has not only a function of relieving the stress, but also a heat conduction function of transferring heat generated in the LED chip 10 to a range wider than the chip size of the LED chip 10 in the metal plate 51. . In the present embodiment, AlN having a relatively high thermal conductivity and insulation is used as the material of the submount member 80, and the LED chip 10 has the cathode electrode on the LED chip 10 side of the submount member 80. It is electrically connected to one conductor pattern 53 via a bonding wire 14 provided on the surface and connected to the cathode electrode (not shown) and a metal fine wire (for example, a gold fine wire, an aluminum fine wire, etc.). The anode electrode is electrically connected to the other conductor pattern 53 via the bonding wire 14. The LED chip 10 and the submount member 80 are bonded using lead-free solder such as AuSn or SnAgCu.

  The material of the submount member 80 is not limited to AlN, and any material may be used as long as the linear expansion coefficient is relatively close to 6H—SiC that is the material of the conductive substrate 11 and the heat conductivity is relatively high. May be adopted.

  The color conversion unit 40 is a mixture of a transparent material such as a silicone resin and a fluorescent material made of particulate yellow phosphor that is excited by blue light emitted from the LED chip 10 and emits broad yellow light. It is formed in a dome shape by the mixture. Therefore, in the LED illumination device of the present embodiment, blue light is radiated from the LED chip 10 by supplying power from a power supply unit (not shown) to the LED chip, and a broad yellow system is emitted from the yellow phosphor of the color conversion unit 40. Therefore, the mixed color light of the light from the LED chip 10 and the light from the yellow phosphor is emitted from the color conversion unit 40 and is emitted to the outside through the lens 60. Here, as the power supply unit, for example, a configuration including a rectifier circuit including a diode bridge that rectifies and smoothes an AC power supply and a smoothing capacitor that smoothes the output of the rectifier circuit may be employed.

  The transparent material used as the material of the color conversion unit 40 is not limited to a silicone resin, but may be, for example, an acrylic resin, an epoxy resin, glass, a material in which an organic material and an inorganic material are combined, or the like. Further, the fluorescent material mixed with the transparent material used as the material of the color conversion unit 40 is not limited to the yellow phosphor. For example, when the LED chip 10 is a blue LED chip, the red phosphor and the green phosphor are mixed. Even white light can be obtained. Further, when the LED chip 10 is a violet to near-ultraviolet LED chip, the fluorescent material in the color conversion unit 40 can obtain white light even if a red phosphor, a green phosphor, and a blue phosphor are mixed. it can.

  By the way, in this embodiment, the same material as the transparent material of the color conversion unit 40 is adopted as the material of the lens 60, and the color conversion unit 40 is molded together with the lens 60 to be integrated with the lens 60. 60 is sealed to the circuit board 50 so as to surround the LED chip 10 with the circuit board 50. Here, the lens 60 is a plano-concave lens, and the light emitted from the LED chip 10 is incident from the concave curved light incident surface 60a and emitted from the planar light emitting surface 60b. The periphery of the light incident surface 60a is sealed to the circuit board 50 over the entire periphery using, for example, an adhesive (for example, a silicone resin, an epoxy resin, or the like). Here, the above-described color conversion unit 40 is embedded in the vicinity of the light incident surface 60 a of the lens 60. The lens 60 is formed in a shape in which the lens diameter gradually increases as the distance from the circuit board 50 increases.

  Thus, in the LED lighting device of the present embodiment, the lens 60 is sealed to the circuit board 50 so as to surround the LED chip 10 with the circuit board 50, and the light emitted from the transparent material and the LED chip 10 is used. Since the color converter 40 that is excited by the fluorescent material that emits light of a color different from the emission color of the LED chip 10 is integrated with the lens 60, the circuit board 50 and the lens 60 can Since the package of the chip 10 is configured, it is not necessary to prepare the packaged LED chip 10 ′ as in the conventional example shown in FIG. 6 and the cost can be reduced, and the color conversion unit 40 is integrated in advance. By preparing a lens 60 and a lens in which the color conversion unit 40 is not integrated, mixed color light of the light emitted from the LED chip 10 and the light emitted from the fluorescent material An LED lighting device for the illumination light, the light emitted from the LED chip 10 with the LED lighting device for the illumination light, can share the LED chip 10 that is not packaged, thereby cost reduction. In the present embodiment, since the color conversion unit 40 is integrated with the lens 60 by being molded simultaneously with the lens 60, the number of components is larger than when the color conversion unit 40 and the lens 60 are separate components. And the management cost of parts can be reduced.

(Embodiment 2)
The basic configuration of the LED lighting device of the present embodiment is substantially the same as that of the first embodiment. As shown in FIG. 2, the light emission color of the LED chip 10 is excited by the blue light emitted from the LED chip 10. A dome-shaped color conversion unit 40 made of a molded product obtained by molding a fluorescent material (for example, yellow phosphor) that emits light of a different color together with a transparent material (for example, silicone resin) is provided on the light incident surface 60a of the lens 60. The difference is that the color conversion unit 40 is integrated with the lens 60 by bonding. Here, the color conversion unit 40 is formed in a shape along the light incident surface 60 a of the lens 60. In addition, the same code | symbol is attached | subjected to the component similar to Embodiment 1, and description is abbreviate | omitted.

  Thus, in the LED lighting device of the present embodiment, similarly to the first embodiment, it is not necessary to prepare the packaged LED chip 10 ′ as in the conventional example shown in FIG. By preparing in advance a lens 60 in which the color conversion unit 40 is integrated and a lens in which the color conversion unit 40 is not integrated, the light emitted from the LED chip 10 and the light emitted from the fluorescent material The LED illumination device that uses the mixed color light as illumination light and the LED illumination device that uses the light emitted from the LED chip 10 as illumination light can share the unpackaged LED chip 10, thereby reducing the cost. In the present embodiment, the lens 60 can be shared regardless of the desired illumination color, and the cost can be reduced. In the present embodiment, the color conversion unit 40 is formed in a dome shape along the light incident surface 60a of the lens 60. However, the color conversion unit 40 is formed in a sheet shape and the planar light of the lens 60 is formed. You may make it integrate with the lens 60 by adhere | attaching on the output surface 60b.

  In the space surrounded by the color conversion unit 40 and the circuit board 50, as shown in FIG. 3, a sealing unit 30 made of a sealing resin (for example, silicone resin) for sealing the LED chip 10 is provided. If the air layer 35 is formed between the sealing part 30 and the color conversion part 40, the assemblability is improved as compared with the case where the sealing part 30 and the color conversion part 40 are brought into close contact with each other. To do. Also in the first embodiment, a sealing unit that seals the LED chip 10 may be provided in a space surrounded by the lens 60 and the circuit board 50 in which the color conversion unit 40 is integrated.

(Embodiment 3)
The basic configuration of the LED lighting device of the present embodiment is substantially the same as that of the second embodiment, and is emitted from the LED chip 10 on the light incident surface on the LED chip 10 side in the color conversion unit 40 as shown in FIG. The only difference is that a wavelength filter 70 that transmits light and reflects light emitted from the color conversion unit 40 is provided. Here, the wavelength filter 70 is formed in a shape along the light incident surface 60 a of the color conversion unit 40. In addition, the same code | symbol is attached | subjected to the component similar to Embodiment 1, and description is abbreviate | omitted.

  Therefore, in the LED lighting device of the present embodiment, compared to the LED lighting device of the second embodiment, it is possible to increase the efficiency of taking out the light emitted from the fluorescent material of the color conversion unit 40 to the outside, and the color rendering property is improved. It becomes possible to raise.

  By the way, in each said embodiment, the number of LED chips 10 mounted in the circuit board 50 is not specifically limited, The circuit board 50 surrounds the lens 60 with which the color conversion part 40 was integrated for every LED chip 10. FIG. Just seal it.

  In each of the above embodiments, a blue LED chip whose emission color is blue is used as the LED chip 10 and a SiC substrate is used as the conductive substrate 11, but a GaN substrate is used instead of the SiC substrate. Alternatively, a sapphire substrate may be used in place of the conductive substrate 11 as the crystal growth substrate. Further, the light emission color of the LED chip 10 is not limited to blue, and may be, for example, red or green. That is, the material of the light emitting portion 12 of the LED chip 10 is not limited to the GaN compound semiconductor material, but depending on the emission color of the LED chip 10, a III-V group compound semiconductor such as a GaAs compound semiconductor material or a GaP compound semiconductor material. A material may be employed, a II-VI group compound semiconductor material may be employed, and the material of the crystal growth substrate may be appropriately changed according to the material of the light emitting portion 12.

1 is a schematic cross-sectional view showing a first embodiment. FIG. 6 is a schematic sectional view showing a second embodiment. It is a schematic sectional drawing which shows the other structural example same as the above. FIG. 6 is a schematic cross-sectional view showing a third embodiment. It is a schematic sectional drawing which shows an example of the conventional light-emitting device. It is a schematic sectional drawing which shows a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 LED chip 14 Bonding wire 40 Color conversion part 50 Circuit board 51 Metal plate 52 Insulating layer 53 Conductive pattern 60 Lens 80 Submount member

Claims (3)

  An LED chip that emits visible light, a circuit board on which the LED chip is mounted, and a lens that controls the light distribution of at least light emitted from the LED chip and surrounds the LED chip between the circuit board and the circuit A lens sealed on a substrate, the lens being a color composed of a transparent material and a fluorescent material that is excited by light emitted from the LED chip and emits light of a color different from the emission color of the LED chip An LED lighting device, wherein the conversion unit is integrated.   The LED lighting device according to claim 1, wherein the color conversion unit is integrated with the lens by being molded simultaneously with the lens.   The LED lighting device according to claim 1, wherein the color conversion unit is integrated with the lens by bonding to the lens.

Images