JP2013045544A - Light-emitting device and led module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a desirable white-light lighting fixture with the use of LEDs in a chromaticity range positioned outside an area of MacAdam ellipse 3step from target color temperature on a blackbody locus which is to be an appropriate illumination color, since purchased LEDs generally have color unevenness of the MacAdam ellipse 3step or more with the distribution center rarely on a blackbody locus, and if LEDs are selected to be a white module on the blackbody locus regulated by JIS, much remainder is produced.SOLUTION: In the light-emitting device 100, a given color temperature on a blackbody locus of a chromaticity diagram is to be a target chromaticity. The light-emitting device 100 is provided with an LED module with four LEDs mounted having a chromaticity point of 130 in a chromaticity range beyond the MacAdam ellipse 3step defined against a target chromaticity of 120, and with a synthetic color of light-emitting color of each LED having nearly the same chromaticity as the target chromaticity of 120.

Description

  The present invention relates to a light emitting device using a light emitting diode (LED).

  In recent years, white LEDs have been widely used for lighting applications, and the amount of light in the LEDs themselves has been increasing. However, in a lighting fixture that requires a large amount of light, a large number of LEDs are used to form a single module. And It is desirable that the white color as the illumination is a color temperature determined by JIS on the black body locus, but currently, a white LED of the same color is prepared for an appliance of a type that uses a large number of LEDs as one module. However, there are many cases where a desired color temperature cannot be obtained due to variations in products. Therefore, in order to suppress the color variation of the LED itself or to eliminate the color variation as an instrument, attempts have been made using a method using LED light mixture (for example, Patent Document 1).

JP 2006-79991 A

  In the method of Patent Document 1, in order to obtain a target light color, a plurality of white LEDs and a plurality of complementary colors are prepared, and light distribution is controlled by an aperture and a lens, so that there is no color unevenness. A spotlight with little variation can be obtained. However, if a complementary LED for a certain white color is prepared, LEDs with unnecessary chromaticity will come out within the range of color variation of the purchased LED, and the amount of light will also decrease due to the aperture being set by the aperture. .

  The purchased LED has a color variation of 3 or more Macadam, and the distribution center is rarely on the black body locus. For this reason, there is a problem that when LEDs are selected so as to be a white module standardized by JIS on a black body locus, a large amount of LEDs appear.

  An object of the present invention is to produce a preferable white luminaire using an LED having a chromaticity range located outside the area of the MacAdam ellipse 3step from a target color temperature on a black body locus that is considered to be an appropriate illumination color. .

The light emitting device of the present invention is
A light emitting device having a predetermined chromatic temperature on a black body locus of a chromaticity diagram as a target chromaticity,
A plurality of LEDs having a chromaticity located in a chromaticity range outside the range of the MacAdam ellipse 3step determined with respect to the target chromaticity, and the combined color of the emission colors of the LEDs is substantially the same as the target chromaticity It is characterized by comprising an LED module on which a plurality of LEDs are mounted.

  According to the present invention, a light source having a preferable illumination color can be obtained for an LED module composed of two or more LEDs.

FIG. 3 is a perspective view of the light-emitting device 100 according to Embodiment 1. The perspective view in the X direction arrow of FIG. FIG. 5 shows assembly of the light-emitting device 100 according to Embodiment 1. FIG. 3 is a simplified diagram of a chromaticity diagram in the first embodiment. 4A and 4B illustrate L / D of the light-emitting device 100 in Embodiment 1. FIG.

Embodiment 1 FIG.
The light-emitting device 100 of Embodiment 1 is demonstrated with reference to FIGS. In the following description, a chromaticity diagram means a CIE1931 chromaticity diagram. The light emitting device 100 is characterized in that each of a plurality of light emitting diodes (hereinafter referred to as LEDs) serving as a light emitting source is located in a chromaticity range outside the range of the Macadam ellipse 3step determined with respect to the target color temperature targeted by the light emitting device 100. It has the color temperature to do.

(External appearance (structure) of light-emitting device 100)
FIG. 1 is a diagram illustrating the structure of the light emitting device 100.
FIG. 2 is a perspective view seen from the X direction of FIG. 1, in which the light source unit of the light emitting device 100 can be seen.
FIG. 3 is a diagram illustrating an assembly relationship among the reflector 113, the LED mounting substrate 111, and the umbrella 115.
FIG. 4 is a simplified diagram of the CIE 1931 chromaticity diagram.

(Structure of the light emitting device 100)
As shown in FIGS. 1 to 3, the light emitting device 100 includes a plurality of LEDs 112 serving as a light source, an LED mounting substrate 111 on which the LEDs 112 are mounted, a reflector 113 having an emission port for each pitch of the LEDs 112, and an instrument And an umbrella 115 covering the outside of the head. The LED mounting substrate 111 on which the LEDs 112 are mounted is referred to as an LED module 110.

(Umbrella 115)
The inside 114 (FIG. 2) of the umbrella 115 is white with high light diffusibility. A hanging cord 118 protrudes from the umbrella 115, and a duct plug 119 is attached to the end thereof. Although not shown, a power source for lighting the LED 112 is housed on the back side (the hanging cord 118 side) of the umbrella 115.

(LED112)
The LED 112 is a white LED, and in the first embodiment, an SMD type LED is assumed. However, a general bullet type LED may be used. The white LED takes the configuration of a general white LED. That is, the white LED is provided with a blue LED and a phosphor-containing resin layer having high transparency so as to cover it, and is surrounded by a package made of a resin such as ceramics. The blue LED is electrically connected by a gold wire, and emits light by electric power supplied from the electrode. The phosphor mixed in the phosphor-containing resin layer is, for example, a YAG (yttrium aluminum garnet) phosphor, which is excited by light emitted from a blue LED, has a spectrum between 480 and 780 nm, and has a main wavelength around 560 nm. Emits light to Since the combined light of these two wavelengths has a complementary color relationship, it becomes pseudo white.

  The material of the phosphor-containing resin layer is an epoxy resin or a silicone resin. Since the light flux of the LED element is reduced by heat, it is preferable to use a silicone resin that is excellent in heat resistance, chemical resistance, self-lubricating property, and friction resistance and is extremely stable as compared with an epoxy resin.

(LED chromaticity)
As shown in FIG. 4, the light emitting device 100 using a plurality of white LEDs as light sources sets a preferable color temperature coordinate point 120 as the illumination color “on the black body locus in the chromaticity diagram of CIE 1931” as the target chromaticity. In order to satisfy this target chromaticity, as shown in FIG. 4, four lights of chromaticity points 130 outside the 3 step area of the MacAdam ellipse determined with respect to the target chromaticity (color temperature coordinate point 120) on the black body locus. A light source (LED module 110) from which the color temperature coordinate point 120 is obtained is configured using (four LEDs 112). As described above, the LED module 110 of the light emitting device 100 is a plurality of LEDs having chromaticity located in the chromaticity range outside the range of the MacAdam ellipse 3step determined with respect to the target chromaticity indicating the color temperature coordinate point 120. A plurality of LEDs in which the combined color of the emission colors of the LEDs has substantially the same chromaticity as the target chromaticity is mounted.

  Since the color combination is an additive color mixture, the LED module 110 having a target chromaticity can be obtained by using two or more LEDs having a chromaticity outside the 3 step area of the MacAdam ellipse determined with respect to the color temperature coordinate point 120. (One set of several LEDs mounted on the substrate) can be made. For example, in the case of a six-light luminaire, the LED module 110 may be configured by three sets of LEDs such that a target light color is obtained by mixing two lights, or a target light color is obtained by mixing six lights. The LED module 110 may be configured by one set. It is a plurality of LEDs having a chromaticity outside the 3 step area of the MacAdam ellipse, and their combined color may be equal to or close to the target chromaticity.

(Umbrella 115)
It is assumed that the inner side 114 of the umbrella 115 is white with high diffusibility. The color of the umbrella (outer color) may be various colors according to the design, but in that case, the inner side is white. By doing so, light can be diffused well and better color mixture light (combined light) can be obtained. Specifically, it is as follows. As shown in FIG. 3, the LED module 110 includes four (plural) LEDs 112 and an LED mounting substrate 111. The LED mounting substrate 111 has a mounting surface 111A on which four LEDs are mounted and a back surface 111B on the opposite side of the mounting surface. As shown in FIG. 2, the light emitting device 100 is a tube-shaped umbrella 115 that houses the LED module 110 inside the tube shape, and the tube-shaped axial direction of the LED mounting substrate 111 (mounting surface 111A). A tube-shaped inner surface 114 that substantially coincides with the direction of the normal line and extends in the direction from the back surface 111B to the mounting surface 111A is at least the tube-shaped end portion from the position of the LED mounting substrate 111 (FIG. 1). It is white over the position.

  The reflector 113 is also assumed to be white for the same reason.

(Light source position)
The umbrella 115 is preferably “the light source unit (LED module) is at a deeper position than usual” like the dotted ellipse in FIG. 1. By taking a sufficient distance from the light source to the emission port 115a, it is difficult to look directly at the light source, and a good-looking instrument can be obtained. In addition, when a color is created using mixed color light, the white color of each lamp is slightly different, but a configuration in which it is difficult for a person to visually recognize directly makes it difficult to see a subtle difference in color. As an application example of the light emitting device 100, a pendant light type lighting device is suitable.
“The light source unit (LED module) is deeper than usual” means, for example, as follows. As shown in FIG. 5, when the light emitting device 100 is installed on the ceiling, it means that it is difficult for the light source (LED) to be seen directly when looking upward at an angle of about 45 degrees from the horizontal. In that case, the aspect ratio regarding the outer diameter φD (mm) of the umbrella 115 and the longitudinal distance L (mm) between the light emitting surface 112a of the LED 112 and the exit port 115a (end of the umbrella 115) is defined as L / D. , L / D is about 0.60 to 1.00.

  The light-emitting device 100 according to the first embodiment uses a plurality of LEDs having chromaticities outside the range of the MacAdam ellipse 3step, and a composite color having a target chromaticity. Therefore, it is possible to reduce the number of LEDs remaining in stock and to obtain a lighting device having a target color temperature.

  DESCRIPTION OF SYMBOLS 100 Light-emitting device, 110 LED module, 111 LED mounting board, 112 LED, 112a Light emission surface, 113 Reflector, 114 Inside, 115 Umbrella, 115a Outlet, 118 Hanging cord, 119 Duct plug, 120 Target chromaticity, 130 chromaticity point.

Claims (4)

A light emitting device having a predetermined chromatic temperature on a black body locus of a chromaticity diagram as a target chromaticity,
A plurality of LEDs having a chromaticity located in a chromaticity range outside the range of the MacAdam ellipse 3step determined with respect to the target chromaticity, and the combined color of the emission colors of the LEDs is substantially the same as the target chromaticity A light-emitting device comprising an LED module on which a plurality of LEDs are mounted. The LED module
The plurality of LEDs;
A mounting surface on which the plurality of LEDs are mounted and a substrate having a back surface opposite to the mounting surface;
The light emitting device
A tube-shaped umbrella, wherein the LED module is housed in the tube shape, and the axial direction of the tube shape substantially coincides with the direction of the normal line of the substrate, from the back surface to the mounting surface direction. The light emitting device according to claim 1, wherein the extending tube-shaped inner surface side is white at least from the position of the substrate to the position of the end of the tube shape. The light emitting device
The light-emitting device according to claim 1, wherein the light-emitting device is a pendant type.   A plurality of LEDs having chromaticity located in a chromaticity range outside the range of the MacAdam ellipse 3step determined with respect to the target chromaticity when a predetermined color temperature on the black body locus of the chromaticity diagram is set as the target chromaticity. An LED module comprising a plurality of LEDs each having a combined color of emitted light of each LED and substantially the same chromaticity as the target chromaticity.