JP2006245080A - Light fixture - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light fixture capable of reducing irregularity in a luminescent color. <P>SOLUTION: The light fixture comprises a substrate 2, an insulator 4, circuit patterns 5a, 5b provided on the substrate via the insulator, a plurality of light-emitting elements 6 arranged in a matrix via the circuit patterns, a reflector 9 that is arranged on the substrate and reflects light irradiated from the plurality of light-emitting elements, a diffusion layer 11 containing a disperging agent for covering the light-emitting elements, a phosphor layer 12 containing a phosphor arranged at the upper side of the diffusion layer, and a light control body having an emission surface for emitting light entering from each light-emitting element. In the light fixture, color temperature becomes lower as a perpendicular light distribution angle becomes larger at a correlation color temperature of 5,000 K or higher. At a perpendicular light distribution angle of 0° or 60°, the correlation color temperature is within 0 to -200 K. At a correlation color temperature of less than 5,000 K, the color temperature becomes higher as the perpendicular color distribution angle becomes larger. At a perpendicular light distribution angle of 0° or 60°, the correlation color temperature is within 0 to +200 K. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an illumination device using a light emitting element as a light source.

  As an example of a conventional light emitting diode (LED) illuminating device, a surface mount type device in which a synthetic resin is filled in a case in which an LED chip is disposed and the LED chip is sealed in the case is known ( For example, see Patent Document 1).

As an example of a conventional example in which white light is emitted by this type of LED device, a mixture of blue light emitted by a blue light emitting LED chip and yellow light emitted by a yellow light emitting LED chip (hereinafter referred to as “light emitting”). The first prior art is known). In addition, as another conventional example, there is one that mixes blue light of a blue light emitting LED chip and yellow light obtained by exciting a yellow light emitting phosphor by this blue light emission (hereinafter referred to as second prior art). Are known.
JP 2002-43625 A

  However, in the first prior art, since there is a distance between the blue light emitting LED chip and the yellow light emitting LED chip, it is difficult to make the mixed color of blue light and yellow light uniform, and other colors other than white light are used. Easy to be. Moreover, a space for installing at least two LED chips that respectively emit blue light and yellow light is required, which leads to an increase in the size of equipment on which the chips are mounted.

  In the second prior art, when viewed from the vertical direction with respect to the outer surface of the sealing resin, almost white light is obtained in the central portion where the blue light emitting LED chip is located, but yellow light is distributed in the peripheral portion. And uneven color occurs. For this reason, when viewed obliquely with respect to the outer surface of the sealing resin, it appears that mainly yellow light is emitted. Further, even in the central part of the outer surface of the sealing resin, the distance between the central part and the blue light emitting LED chip is closer than the distance between the peripheral part and the blue light emitting LED chip. The blue light is lost and the white light appears bluish.

  An object of this invention is to provide the illuminating device which can reduce the color nonuniformity of luminescent color.

  The invention of claim 1 is a substrate, an insulator disposed on the substrate, a circuit pattern disposed on the substrate via the insulator, and a plurality of light emitting elements disposed in a matrix via the circuit pattern An element, a reflector disposed on the substrate and reflecting light emitted from the plurality of light emitting elements, a diffusion layer including a diffusing agent covering the light emitting element, and a phosphor disposed above the diffusion layer In a lighting device comprising a phosphor layer including a light control body having an exit surface that emits light incident from each of the light emitting elements, the color temperature increases as the vertical light distribution angle increases at a correlated color temperature of 5000 K or more. When the vertical light distribution angle is 0 ° to 60 °, the correlated color temperature is within 0 to −200K. When the correlated color temperature is less than 5000K, the color temperature increases as the vertical light distribution angle increases. Light angle 0 ° to 60 ° Oite, wherein the correlated color temperature is configured to be within 0 to + 200K.

  The material of the substrate is glass epoxy resin, aluminum, aluminum nitride, or the like, but a substrate containing aluminum has good heat dissipation and suppresses a temperature increase of the light emitting element, thereby suppressing a decrease in luminous efficiency and element deterioration. The insulator is necessary when a metal material is selected as the material of the substrate, but is not necessary in the case of a glass epoxy resin substrate. The circuit pattern is formed of a copper pattern, and, for example, light emitting diodes as a plurality of light emitting elements are electrically connected between the positive electrode and the negative electrode. A plurality of light emitting elements are arranged in a matrix on the substrate to form a surface light source. The reflector is formed of a white resin and has a reflecting surface so as to surround the periphery of the light emitting element.

  The emitted light of the light emitting element is reflected by the reflecting surface. The phosphor layer is obtained by mixing a phosphor into a silicone resin or the like, and converts it into visible light by light from the light emitting element. Alternatively, the light emitting element may be covered with a diffusing material, and a phosphor layer may be disposed on the diffusing material. This configuration diffuses the light emitted from the phosphor layer by the diffusing material, suppresses the increase in the brightness of the opposed area of the light control body, and brings the brightness ratio with the brightness of the peripheral area close to 1. It works to let you. The light control body is formed of an acrylic resin or the like, and is optically designed for each light emitting element.

  When the correlated color temperature is 5000K or more, the correlated color temperature is within 0 to -200K at a vertical light distribution angle of 0 ° to 60 °. When the correlated color temperature is less than 5000K, the correlated color is at a vertical light distribution angle of 0 ° to 60 °. Since the temperature is within 0 to +200 K, almost white light is obtained at any of the central portion and the peripheral portion where the blue light emitting LED chip is located, and the occurrence of uneven color is suppressed.

  According to a second aspect of the present invention, in the illumination device according to the first aspect, the diffusion layer is formed by adding 3 to 5% by mass of a diffusing agent to the resin. When the addition amount of the diffusing agent is zero, that is, when the luminous flux without the addition amount of the diffusing agent is 100%, if the addition amount of the diffusing agent exceeds 5 mass%, the luminous flux decreases, and the addition amount is 3 mass%. If the ratio is less than 1, the effect of reducing color unevenness decreases, so the above range is suitable.

  In the first and second aspects of the present invention, the light emission of the light emitting element is diffused in multiple directions by the diffusion layer, whereby the phosphor layer is excited from multiple directions to emit fluorescence, and at a correlated color temperature of 5000 K or more, the vertical light distribution angle. Since the correlated color temperature is within 0 to -200K at 0 ° to 60 °, and the correlated color temperature is less than 5000K, the correlated color temperature is within 0 to + 200K at the vertical light distribution angle of 0 ° to 60 °. Almost white light can be obtained at any of the central portion and the peripheral portion where the light emitting LED chip is located, and the occurrence of color unevenness can be suppressed.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a plan view of a lighting device according to an embodiment of the present invention, FIG. 2 is a cross-sectional view taken along the line II-II in FIG. 1, and FIG. As shown in the figure, the lighting device 1 has a plurality of light emitting devices 3, 3... Arranged on a substrate 2 in a matrix of, for example, 3 rows and 3 columns, and are integrally connected. The substrate 2 is made of a flat plate made of aluminum (Al), Ni, glass epoxy or the like having heat dissipation and rigidity, and a lead frame 5 is disposed on the substrate 2 via an electrical insulator 4.

  As shown in FIG. 3, the lead frame 5 has cathode and anode circuit patterns (wiring patterns) 5a and 5b formed of an alloy of Cu and Ni, Au, or the like for each LED device 3, and this lead frame. 5, a blue light emitting LED chip 6 as a light emitting element is mounted for each light emitting device 3. Each blue light emitting LED chip 6 is made of, for example, a gallium nitride (GaN) semiconductor that emits blue light. Each blue light emitting LED chip 6 has its bottom electrode placed on one of the circuit patterns 5a and 5b to be electrically connected, while its top electrode is connected to the other of the circuit patterns 5a and 5b by a bonding wire 7. Yes.

  And on the board | substrate 2, the circumference | surroundings of each blue light emission LED chip 6 are surrounded at a required space | interval, and the reflective surface which spreads gradually toward the other side (FIG. 2, FIG. 3 upper direction) of the board | substrate 2 is comprised. Each of the LED devices 3 is formed with a reflector 9 having conical conical recesses 8 formed concentrically, and these are integrally formed. The reflector 9 is made of, for example, a synthetic resin such as PBT (polybutylene terephthalate), PPA (polyphthalamide), PC (polycarbonate), and each recess 8 has an opening 8a that opens to the outside.

  Each recess 8 is filled with a thermosetting transparent resin such as translucent silicone rubber or epoxy resin as a sealing resin 10. The sealing resin 10 is formed in two layers: a diffusion layer 11 on the blue light emitting LED chip 6 side and a yellow light emitting phosphor layer 12 as a phosphor layer on the concave opening 8a side.

The diffusion layer 11 is a blue light emitting sealing resin obtained by adding 3 to 5 mass% (mass%) of a diffusing agent such as alumina (Al ₂ O ₃ ), Ti, Ca, Si, Al, or Y in the recess 8. It is formed by injecting to a position higher than the LED chip 6 and thermosetting, and the boundary surface 11a with the phosphor layer 12 is formed in a curved surface recessed to the blue light emitting LED chip 6 side (lower surface side in FIG. 3). Yes. The curved boundary surface 11a is preferably 1 μm to 5 μm, for example, between the upper end and the lower end of the curve.

  Moreover, since the addition amount of the diffusing agent added to the sealing resin 10 of the diffusion layer 11 is 3 to 5% by mass, it is possible to reduce the color unevenness of white light without reducing the luminous flux. Table 1 below shows changes in luminous flux depending on the amount of diffusing agent added. In addition, when the addition amount of the diffusing agent is zero, that is, when the addition amount of the diffusing agent is 100%, when the addition amount of the diffusing agent exceeds 5% by mass, the light flux is decreased and the addition amount is 3 When the content was less than mass%, the effect of reducing color unevenness decreased.

  The yellow light-emitting phosphor layer 12 is sealed by adding the required mass% of a yellow light-emitting phosphor that receives blue light from the LED chip 6 and fluoresces yellow after the thermosetting formation of the diffusion layer 11. It is configured by injecting resin and thermosetting.

  Next, the effect | action of this illuminating device 1 is demonstrated. First, when a predetermined DC voltage is applied between the cathode-side and anode-side circuit patterns 5a and 5b from the outside, each blue light-emitting LED chip 6 emits blue light. This blue light emission is diffused in multiple directions by the diffusion layer 11 and then enters the yellow light emitting phosphor layer 12, where the yellow phosphor is excited from multiple directions to emit yellow light and is mixed with this yellow color. It becomes white light and is radiated to the outside from each recess opening 8a.

  Therefore, according to this LED illumination device 1, minute light emission of the blue light emitting LED chip 6 is diffused in multiple directions by the diffusion layer 11, and the yellow phosphor of the phosphor layer 12 is excited from multiple directions to emit yellow light. In addition, since the yellow light and the blue light are mixed to emit white light, the color unevenness of the white light can be reduced.

  That is, as shown in FIG. 4, when the correlated color temperature is 5000 K or higher, the correlated color temperature is within 0 to -200 K at a vertical light distribution angle of 0 ° to 60 °. If the correlated color temperature is less than 5000 K, the correlated color temperature is within 0 to +200 K at a vertical light distribution angle of 0 ° to 60 °. In this case, almost white light is obtained at any of the central portion and the peripheral portion where the blue light emitting LED chip is located, and the occurrence of color unevenness can be suppressed.

Next, the sample No. The experimental data of the uneven color reduction effect implemented about 1-5 are shown. Note that. In this experiment, a yellow phosphor having an emission wavelength of 545 mm, Al ₂ O ₃ C made by Nippon Aerosil as a diffusing agent, and JCR6140 made by Toray Dow Silicone as a sealing resin 10 were used.

(experimental method)

Sample No. 1 …… Phosphor only

Phosphor layer

Silicone rubber (JCR6140) …… 89 mass%

Yellow phosphor: 10 mass%

Red phosphor: 1 mass%

Sample No. 2 ... Diffusion layer (5 mass%) + phosphor (two-layer structure)

Diffusion layer

Silicone rubber (JCR6140) ...... 95 mass%

Diffusing agent (Al ₂ O ₃ ) 5 mass%

Phosphor layer

Silicone rubber (JCR6140) ...... 78mass%

Yellow phosphor: 20 mass%

Red phosphor ... 2 mass%

Sample No. 3 …… Diffusion layer (10 mass%) + phosphor (two-layer structure)

Diffusion layer

Silicone rubber (JCR6140) …… 90 mass%

Diffusing agent (Al ₂ O ₃ ) 10 mass%

Phosphor layer

Silicone rubber (JCR6140) ...... 78mass%

Yellow phosphor: 20 mass%

Red phosphor ... 2 mass%

Sample No. 4 ... Diffusion layer (15 mass%) + phosphor (two-layer structure)

Diffusion layer

Silicone rubber (JCR6140) ...... 85mass%

Diffusing agent (Al ₂ O ₃ ) 15 mass%

Phosphor layer

Silicone rubber (JCR6140) ...... 78mass%

Yellow phosphor: 20 mass%

Red phosphor ... 2 mass%

Sample No. 5 ...... Diffusing agent mixed phosphor

Silicone rubber (JCR6140) ...... 80mass%

Diffusing agent (Al ₂ O ₃ ) 20 mass%

Silicone rubber (JCR6140) ...... 78mass%

Yellow phosphor: 20 mass% red phosphor

Red phosphor ... 2 mass%

(Experimental result)

  1. Sample No. In the case of a one-layer structure in which the diffusion layer 11 is deleted as shown in FIG. Similarly, in the case of a single layer structure in which the diffusion layer 11 is deleted and a diffusing agent is added to the phosphor layer 12 as in 5, the white light radiated to the outside from the recess opening 8a is distributed in the peripheral portion of the yellow light. The effect of reducing color unevenness was not obtained.

  2. Sample No. 3, No. In the case of the two-layer structure of each of the diffusion layers 11 and the phosphor layer 12 in which the addition amount of the diffusion agent is 10% by mass (mass%) or 15% by mass as in 4, the addition amount of the diffusion agent is large. The viscosity of the diffusion layer 11 increases, and uneven coating of the diffusion layer 11 occurs. For this reason, the white light radiated to the outside from the recess opening 8a has yellow light distributed around the periphery thereof, and the effect of reducing the color unevenness cannot be obtained.

  3. Sample No. In the case of the two-layer structure of the diffusion layer 11 in which the addition amount of the diffusing agent is 5% by mass and the phosphor layer 12 in which the addition amount of the phosphor is 20% by mass as shown in FIG. Almost no yellow light distribution was observed at the peripheral edge of the light, and the effect of reducing the color unevenness of the white light was obtained.

  If the addition ratio of the diffusing agent in the diffusion layer 11 is more than 5% by mass, the amount of light emitted from the blue light emitting LED chip 6 and the like is absorbed by the substrate 2 made of Ni or the like. The luminous flux of white light radiated on the screen is reduced.

  In view of this, the light receiving surface of the substrate 2 may be coated with a reflective material such as a white paint to form the reflective surface, thereby preventing or suppressing a decrease in luminous flux.

The top view of the LED lighting apparatus which concerns on embodiment which concerns on this invention. Similarly, the II-II sectional view taken on the line of FIG. Similarly, the III part enlarged view of FIG. Similarly, the figure which shows the correlation color temperature in the vertical light distribution angle.

Explanation of symbols

  2 substrate, 4 insulator, 5a, 5b circuit pattern, 6 light emitting element, 9 reflector, 11 diffusion layer, 12 phosphor layer.

Claims (2)

A substrate, an insulator disposed on the substrate, a circuit pattern disposed on the substrate via the insulator, a plurality of light emitting elements disposed in a matrix via the circuit pattern, and the substrate. A reflector that reflects light emitted from the plurality of light emitting elements, a diffusion layer that includes a diffusing agent that covers the light emitting elements, and a phosphor layer that includes a phosphor disposed above the diffusion layer; In a lighting device comprising a light control body having an exit surface that emits light incident from each of the light emitting elements,
At a correlated color temperature of 5000 K or higher, the color temperature decreases as the vertical light distribution angle increases. At a vertical light distribution angle of 0 ° to 60 °, the correlated color temperature is within 0 to −200 K, and below the correlated color temperature of 5000 K. The illumination device is configured such that the color temperature increases as the vertical light distribution angle increases, and the correlated color temperature is within 0 to +200 K at a vertical light distribution angle of 0 ° to 60 °.   The lighting device according to claim 1, wherein the diffusion layer is formed by adding 3 to 5 mass% of a diffusing agent to the resin.

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