JP7296579B2 - lighting equipment - Google Patents

Description

The present invention relates to lighting devices.

2. Description of the Related Art A lighting device is known that has a function of changing the correlated color temperature of illumination light according to the purpose of use, the usage situation, or the like. A lighting device having a function capable of changing the correlated color temperature is provided with, for example, two or more light-emitting units with different light colors, and by changing the ratio of the light amounts of the respective light-emitting units, the amount of emitted white light can be changed. Vary the correlated color temperature. Patent Literature 1 discloses an illumination device provided with three light sources of different light colors in order to change the chromaticity coordinates of emitted white light along the blackbody locus, which is an arc-shaped curve in the chromaticity coordinates. . The illumination device of Patent Document 1 includes two light sources having chromaticity coordinates near the blackbody locus and having different correlated color temperatures, and a light source having chromaticity coordinates within the yellow region.

JP 2009-123429 A

In a lighting device that can change the correlated color temperature, depending on the application, it is white light that has the chromaticity coordinates of the black body locus and at the same time, white light that can faithfully express the color of an object existing in the lighting space. , white light with high color rendering properties.

For example, conventionally, in situations where light bulbs based on the principle of black body radiation were used as the light source, the brightness of studio lighting, etc., changes due to dimming, and the black body radiation locus (hereafter referred to as the black body radiation locus) The correlated color temperature also varies along the body (radial) locus or blackbody locus (sometimes abbreviated as blackbody locus). Even if an attempt is made to simulate such a scene by using two LED (Light Emitting Diode) light sources with different correlated color temperatures and changing the light mixing ratio, the chromaticity of the mixed light is the same as that of a black body. It does not follow a radial trajectory, and only changes linearly between the set chromaticity coordinates of two colors (for example, xy chromaticity coordinates).

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide an illumination device capable of changing the correlated color temperature of white light emitted along the chromaticity coordinates of the black body locus and simultaneously improving the color rendering properties of the emitted white light. and

To achieve the above object, a lighting device according to an aspect of the present invention includes a first light emitting unit that emits first light; and a second light emission that emits second light having a correlated color temperature lower than that of the first light. and a straight line connecting the chromaticity coordinates of the first light and the chromaticity coordinates of the second light in the CIE xy chromaticity diagram. a third light emitting unit; and a control unit that adjusts the light intensity of each of the first light emitting unit, the second light emitting unit, and the third light emitting unit, wherein the third light is the first light and the third light emitting unit. It has an emission spectrum corresponding to the color gamut area ratio of each of the two lights.

According to the illumination device of the present invention, it is possible to change the correlated color temperature of the white light emitted along the chromaticity coordinates of the black body locus and at the same time improve the color rendering of the emitted white light.

FIG. 1 is a diagram showing a schematic configuration of a lighting device according to an embodiment. FIG. 2 is a schematic diagram showing cross sections of a first light emitting unit, a second light emitting unit, and a third light emitting unit of the lighting device according to the embodiment. FIG. 3 is a CIE xy chromaticity diagram showing an example of chromaticity coordinates of the first light, the second light, and the third light of the lighting device according to the embodiment. 4A is a diagram showing an emission spectrum of the first light of the lighting device in Example 1. FIG. 4B is a diagram showing an emission spectrum of the second light of the lighting device in Example 1. FIG. 4C is a diagram showing an emission spectrum of the third light of the lighting device in Example 1. FIG. 4D is a diagram showing color deviation Duv of light emitted by the lighting device in Example 1. FIG. 4E is a diagram showing a color rendering index of light emitted by the lighting device in Example 1. FIG. 5A is a diagram showing an emission spectrum of the first light of the lighting device in Example 2. FIG. 5B is a diagram showing an emission spectrum of the second light of the lighting device in Example 2. FIG. 5C is a diagram showing an emission spectrum of the third light of the lighting device in Example 2. FIG. FIG. 5D is a diagram showing color deviation Duv of light emitted by the lighting device in Example 2; 6A is a diagram showing an emission spectrum of the first light of the lighting device in Example 3. FIG. 6B is a diagram showing the emission spectrum of the second light of the lighting device in Example 3. FIG. 6C is a diagram showing an emission spectrum of the third light of the lighting device in Example 3. FIG. 6D is a diagram showing color deviation Duv of light emitted by the lighting device in Example 3. FIG. 7A is a diagram showing an emission spectrum of the first light of the lighting device in Example 4. FIG. 7B is a diagram showing an emission spectrum of the second light of the lighting device in Example 4. FIG. 7C is a diagram showing an emission spectrum of the third light of the lighting device in Example 4. FIG. FIG. 7D is a diagram showing color deviation Duv of light emitted by the lighting device in Example 4; 8A is a diagram showing the emission spectrum of the first light of the lighting device in Example 5. FIG. 8B is a diagram showing the emission spectrum of the second light of the lighting device in Example 5. FIG. 8C is a diagram showing an emission spectrum of the third light of the lighting device in Example 5. FIG. 8D is a diagram showing color deviation Duv of light emitted by the lighting device in Example 5. FIG.

(Embodiment)
Hereinafter, embodiments will be specifically described with reference to the drawings. It should be noted that the embodiments described below are all comprehensive or specific examples. Numerical values, shapes, materials, components, arrangement positions and connection forms of components, steps, order of steps, and the like shown in the following embodiments are examples and are not intended to limit the present invention. In addition, they are schematic diagrams that have been appropriately emphasized, omitted, or adjusted in proportion to show the present invention, and are not necessarily strictly illustrated, and may differ from the actual shape, positional relationship, and proportion. .

Further, in this specification, the numerical value of the color deviation Duv is the numerical value of Duv, which is the notation of the color deviation from the black body (radiation) locus defined by JIS Z8725, that is, 1000 times the numerical value of duv. In other words, in this specification, unless otherwise specified, the numerical value of the color deviation Duv is 1000 times the numerical value of duv according to JIS Z8725.

[composition]
First, the illumination device according to this embodiment will be described.

FIG. 1 is a diagram showing a schematic configuration of a lighting device 100 according to this embodiment. As shown in FIG. 1 , lighting device 100 includes first light emitting unit 10 , second light emitting unit 20 , third light emitting unit 30 and control unit 40 . The lighting device 100 is, for example, a ceiling light as shown in FIG. 1, and may be a base light, a downlight, a fixture shape such as a floodlight, or a lamp shape lighting device such as a light bulb.

The first light emitting unit 10, the second light emitting unit 20, and the third light emitting unit 30 are light emitting units that emit light of different chromaticities. The first light emitting unit 10 emits first light, and the second light emitting unit 20 emits second light having a lower correlated color temperature than the first light. In the CIE xy chromaticity diagram, the third light emitting unit 30 emits the third light having chromaticity coordinates at a position where the blackbody locus is sandwiched by a straight line connecting the chromaticity coordinates of the first light and the chromaticity coordinates of the second light. emit. That is, in the CIE xy chromaticity diagram, the chromaticity coordinates of the third light are defined by at least a part of a straight line connecting the chromaticity coordinates of the third light, the chromaticity coordinates of the first light, and the chromaticity coordinates of the second light. , are the chromaticity coordinates that can span the blackbody locus. Further, in the CIE xy chromaticity diagram, at least part of a straight line connecting the chromaticity coordinates of the first light and the chromaticity coordinates of the second light exists in a region where the color deviation Duv is smaller than 0, and the color of the third light The degree coordinates may be chromaticity coordinates located in a region where the color deviation Duv is greater than zero.

The control unit 40 receives control information from the outside and adjusts the ratio of the light amounts of the first light emitting unit 10 , the second light emitting unit 20 and the third light emitting unit 30 . Thereby, the white light generated by mixing the first light, the second light, and the third light is toned. In this specification, white light refers to the range of daylight color (symbol D), neutral white (symbol N), white (symbol W), warm white (symbol WW), and light bulb color (symbol L), or Means the light color for illumination along the black body radiation locus or synthetic daylight locus having a correlated color temperature above or below, and intends the narrowly defined range of white (symbol W) in the chromaticity division of light color not a thing

For example, the control unit 40 supplies power to the first light emitting unit 10, the second light emitting unit 20, and the third light emitting unit 30 independently from a power supply circuit, and individually changes the amount of current to control the first light, The light amount of each of the second light and the third light is adjusted (that is, dimming). Also, the control of the control unit 40 includes lighting and extinguishing. Specifically, the control unit 40 includes a dimming switch, a power supply circuit, a current control circuit, a dimming circuit, and the like. The control unit 40 may further include a processor, microcomputer, or the like. The control unit 40 may also include a communication module or the like for remote control.

Next, the first light emitting section 10, the second light emitting section 20 and the third light emitting section 30 will be described in detail. FIG. 2 is a schematic diagram showing cross sections of the first light emitting unit 10, the second light emitting unit 20, and the third light emitting unit 30 of the lighting device 100 according to the present embodiment.

As shown in FIG. 2 , the first light emitting unit 10 includes a first light emitting element 11 , a first fluorescent member 12 that converts the wavelength of at least part of the light emitted by the first light emitting element 11 , and a sealing member 50 . The first light emitting unit 10 is a COB (Chip On Board) type light emitting module. is stopped. Although not shown, the first light emitting element 11 is provided with metal wiring or the like for supplying electric power.

The second light emitting unit 20 includes a second light emitting element 21 , a second fluorescent member 22 that converts the wavelength of at least part of the light emitted by the second light emitting element 21 , and a sealing member 50 . The third light emitting unit 30 also includes a third light emitting element 31 , a third fluorescent member 32 that converts the wavelength of at least part of the light emitted by the third light emitting element 31 , and a sealing member 50 . Since the second light emitting section 20 and the third light emitting section 30 have the same structure as the first light emitting section 10, detailed description thereof will be omitted. Power is supplied to the second light emitting unit 20 and the third light emitting unit 30 by a circuit separate from that of the first light emitting unit 10 .

Also, the first light emitting unit 10, the second light emitting unit 20, and the third light emitting unit 30 may be SMD (Surface Mount Device) type light emitting modules. Further, the first light emitting unit 10, the second light emitting unit 20 and the third light emitting unit 30 may be light emitting modules such as CSP (Chip Scale Package) type or remote phosphor type. Further, when the first light emitting unit 10, the second light emitting unit 20, and the third light emitting unit 30 are remote phosphor type light emitting modules, the vacuum sealing LED package structure is not sealed by the sealing member 50. It is possible to make changes such as The numbers of the first light emitting units 10, the second light emitting units 20, and the third light emitting units 30 may be appropriately adjusted according to the purpose of use.

The first light emitting unit 10 mixes the light emitted by the first light emitting element 11 and the light wavelength-converted by the first fluorescent member 12 to emit the first light. The second light emitting unit 20 mixes the light emitted by the second light emitting element 21 and the light wavelength-converted by the second fluorescent member 22 to emit the second light. The third light emitting unit 30 mixes the light emitted by the third light emitting element 31 and the light wavelength-converted by the third fluorescent member 32 to emit the third light.

The first light emitting element 11, the second light emitting element 21, and the third light emitting element 31 are, for example, LEDs that emit blue light with an emission peak wavelength of 420 nm or more and 470 nm or less. The first light emitting element 11, the second light emitting element 21, and the third light emitting element 31 may be LEDs having the same peak emission wavelength, or may be LEDs having different peak emission wavelengths. From the viewpoint of making the current-voltage characteristics the same and facilitating the power supply circuit design, for example, the first light emitting element 11, the second light emitting element 21, and the third light emitting element 31 are LEDs of a type having the same emission peak wavelength. . Note that the first light emitting element 11, the second light emitting element 21 and the third light emitting element 31 may be collectively referred to simply as "light emitting elements". The light-emitting element may be an LED that emits light with an emission peak wavelength of near-ultraviolet or ultraviolet wavelengths.

The first fluorescent member 12 is excited by at least part of the light from the first light emitting element 11 and emits light with a longer wavelength than the light from the first light emitting element 11 . Similarly, the second fluorescent member 22 is excited by at least part of the light from the second light emitting element 21 and emits light with a longer wavelength than the light from the second light emitting element 21 . The third fluorescent member is excited by at least part of the light from the third light emitting element 31 and emits light with a longer wavelength than the light from the third light emitting element 31 . Note that the first fluorescent member 12, the second fluorescent member 22 and the third fluorescent member 32 may be collectively referred to simply as "fluorescent members".

Each of the first fluorescent member 12, the second fluorescent member 22, and the third fluorescent member 32 includes, for example, a phosphor having an emission peak in a light wavelength range from bluish green to red.

Phosphors having an emission peak in the wavelength range of light from blue-green to green include, for example, garnet phosphors (LuAG phosphor, etc.), silicate phosphors (BOSE phosphor, etc.), and nitride phosphors (BaSiON phosphor, βSiAlON phosphor, etc.). In this specification, the wavelength range of light from bluish green to green is 470 nm or more and 540 nm or less.

Examples of phosphors having an emission peak in the wavelength range of yellow light include garnet phosphors (YAG phosphor, LuAG phosphor, etc.), silicate phosphors (BOSE phosphor, etc.), and nitride phosphors ( αSiAlON phosphor, SLA phosphor, LSN phosphor, etc.) and the like. In this specification, the wavelength range of yellow light is 540 nm or more and 600 nm or less. Since yellow light emits light with a wide spectral width, even if the main emission intensity is in the above wavelength range of 540 nm or more and 600 nm or less, the emission peak position may be located at 500 nm or more and 540 nm or less. be. Therefore, in this specification, light whose emission peak position is located in the wavelength range of 500 nm or more and 540 nm or less and whose main emission intensity is in the wavelength range of 540 nm or more and 600 nm or less is also classified as yellow. LuAG phosphors and LSN phosphors are examples of yellow-emitting phosphors that emit light whose emission peak position is in the wavelength range of 500 nm or more and 540 nm or less and whose main emission intensity is in the wavelength range of 540 nm or more and 600 nm or less. be done.

Phosphors having an emission peak in the wavelength range of red light include, for example, nitride-based phosphors (αSiAlON phosphors, CASN phosphors, SCASN phosphors, SLA phosphors, SALON phosphors, etc.). Further, the phosphor having an emission peak in the wavelength range of red light is not limited to the nitride-based phosphor, and may be a fluoride phosphor (KFS phosphor, MFG phosphor, etc.) exhibiting narrow-band emission. . In this specification, the wavelength range of red light is 600 nm or more and 700 nm or less.

The number of types of phosphor contained in each of the first fluorescent member 12, the second fluorescent member 22, and the third fluorescent member 32 may be one, or two or more. From the viewpoint of enhancing the color rendering properties of the first light and the second light, for example, the first fluorescent member 12 and the second fluorescent member 22 are provided with fluorescent light having emission peaks in the wavelength ranges of light from bluish green to green, yellow and red. It is preferable that two or more kinds of phosphors are included in the substance.

The types and compounding ratios of the phosphors contained in the first fluorescent member 12, the second fluorescent member 22, and the third fluorescent member 32, respectively, and the compounding amounts in the sealing member 50 are determined according to the desired first light and second light. and the third light are adjusted to have respective emission spectrum shapes. Specifically, the kind of phosphor contained in each of the first fluorescent member 12 and the second fluorescent member 22, the compounding ratio, and the compounding amount in the sealing member 50 are such that the second light is more intense than the first light. Adjusted to lower the correlated color temperature. In addition, regarding the type of phosphor contained in the third fluorescent member 32, the compounding ratio, and the compounding amount in the sealing member 50, the third light is on the positive side of the black body radiation locus in the CIE xy chromaticity diagram. (chromaticity coordinates where the color deviation Duv is greater than 0), the upper y value is on the high side, and preferably, the black body radiation locus is defined by a straight line connecting the chromaticity coordinates of the first light and the chromaticity coordinates of the second light. It is adjusted so that it becomes the chromaticity coordinates of the sandwiched position. Further, the type and compounding ratio of the phosphor contained in the third fluorescent member 32 and the compounding amount in the sealing member 50 are determined so that the emission spectrum of the third light has a desired shape. It is adjusted according to the color gamut area ratio of light. Details of the emission spectrum of the third light will be described later.

The sealing member 50 is a translucent resin material that individually seals the first light emitting element 11, the second light emitting element 21, and the third light emitting element 31, respectively. The translucent resin material is a material that transmits light emitted by the first light emitting element 11, the second light emitting element 21, the third light emitting element 31, the first fluorescent member 12, the second fluorescent member 22, and the third fluorescent member 32. If so, it is not particularly limited. As the translucent resin material, for example, silicone resin, epoxy resin, or urea resin is used. Note that in FIG. 2, the first light emitting unit 10, the second light emitting unit 20, and the third light emitting unit 30 have the same type of sealing member 50, but the first light emitting unit 10 and the second light emitting unit The section 20 and the third light emitting section 30 may have different types of sealing members.

The substrate 60 is a substrate on which the first light emitting unit 10, the second light emitting unit 20 and the third light emitting unit 30 are mounted. The substrate 60 is, for example, a resin substrate, a metal base substrate, a metal core substrate, or a ceramic substrate.

[motion]
Next, the operation of lighting device 100 according to the present embodiment will be described.

When power is supplied to the lighting device 100 , the first light emitting unit 10 , the second light emitting unit 20 , and the third light emitting unit 30 emit light under the control of the control unit 40 . That is, the illumination device 100 emits white light in which the first light emitted by the first light emitting unit 10, the second light emitted by the second light emitting unit 20, and the third light emitted by the third light emitting unit 30 are mixed. .

The first light is mixed light of light emitted by the first light emitting element 11 and the first fluorescent member 12 . Therefore, the emission spectrum of the first light has peaks derived from the light emissions of the first light emitting element 11 and the first fluorescent member 12 . Similarly, the emission spectrum of the second light has peaks originating from the light emitted from the second light emitting element 21 and the second fluorescent member 22 . The emission spectrum of the third light has peaks derived from the light emitted from the third light emitting element 31 and the third fluorescent member 32 . When the fluorescent member absorbs almost all of the light from the light emitting element, the emission spectrum of the first light, the second light, and the third light cannot be measured and distinguished from the peak of the emission spectrum originating from the light emitting element. may

The control unit 40 individually adjusts the amount of current to the first light emitting unit 10, the second light emitting unit 20, and the third light emitting unit 30, and the first light emitting unit 10, the second light emitting unit 20, and the third light emitting unit 30 By varying the amount of light, the emitted white light is toned. Note that the control unit 40 may have a light emitting unit to which power is not supplied depending on the target light color.

FIG. 3 is a CIE xy chromaticity diagram showing an example of chromaticity coordinates of the first light, the second light, and the third light of the illumination device 100 according to this embodiment. FIG. 3 shows an example in which the first light has chromaticity coordinates L1, the second light has chromaticity coordinates L2, and the third light has chromaticity coordinates L3. As shown in FIG. 3, the first light and the second light have different correlated color temperatures, and the correlated color temperature of the second light is lower than the correlated color temperature of the first light. The chromaticity coordinates L3 of the third light are chromaticity coordinates at a position where the blackbody locus is sandwiched by at least a part of the straight line connecting the chromaticity coordinates L1 of the first light and the chromaticity coordinates L2 of the second light.

Here, regarding the white light emitted by the illumination device 100, light obtained by mixing the first light and the second light is defined as first white light, and light obtained by further mixing the first white light and the third light is defined as second white light. A case will be described. The mixing ratio of the first white light and the second light in the first white light and the mixing ratio of the first white light and the third light in the second white light are adjusted by the controller 40 .

The first white light is adjusted to white light having a correlated color temperature between the correlated color temperature of the first light and the correlated color temperature of the second light according to the mixing ratio of the first light and the second light. be. At this time, the chromaticity coordinates of the first white light are chromaticity coordinates on a straight line connecting the chromaticity coordinates L1 of the first light and the chromaticity coordinates L2 of the second light. Since the blackbody locus is an upwardly convex curve in the CIE xy chromaticity diagram, the chromaticity coordinates of the first white light deviate from the chromaticity coordinates of the blackbody locus when the correlated color temperature is changed. Become.

The chromaticity coordinates of the second white light obtained by mixing the first white light with the third light are the chromaticity coordinates shifted from the chromaticity coordinates of the first white light toward the chromaticity coordinates L3 of the third light. . The chromaticity coordinates L3 of the third light are chromaticity coordinates at a position where the blackbody locus is sandwiched between a straight line connecting the chromaticity coordinates L1 of the first light and the chromaticity coordinates L2 of the second light. Therefore, even if the chromaticity coordinates of the first white light deviate from the blackbody locus, the second white light is mixed with the first white light and the third light, resulting in the blackbody locus. Adjusted to chromaticity coordinates. Therefore, lighting device 100 can change the correlated color temperature of white light emitted along the chromaticity coordinates of the blackbody locus. Note that the chromaticity coordinates of the first light, the second light, and the third light may be changed from the example shown in FIG. 3 depending on the range of correlated color temperatures to be toned.

Also, as shown in FIG. 3, the chromaticity coordinates L3 of the third light are chromaticity coordinates located in a region where the color deviation Duv is greater than zero. As a result, by mixing the third light with the light of the chromaticity coordinates in the region where the color deviation Duv is negative, the color can be adjusted to the chromaticity coordinates of the black body locus. Further, from the viewpoint of facilitating adjustment of the chromaticity coordinates of the second white light, the chromaticity coordinates L3 of the third light may be the chromaticity coordinates of an area where the color deviation Duv is 10 or more. Furthermore, the chromaticity coordinates L3 of the third light may be in a region where the color deviation Duv is 20 or more, which makes it easier to perform color toning using the third light.

Also, for example, the chromaticity coordinates L3 of the third light are (x, y)=(0.28, 0.68), (x, y)=(0.2, 0 . 62), (x, y) = (0.08, 0.54), (x, y) = (0.07, 0.46), (x, y) = (0.14, 0.38) , (x,y)=(0.29,0.38), (x,y)=(0.51,0.48) and (x,y)=(0.28,0.68) points may be chromaticity coordinates located within a region surrounded by . The third light emitting unit 30 that emits the third light having such chromaticity coordinates can be easily obtained by adjusting the type and blending ratio of the phosphor contained in the third fluorescent member 32 and the blending amount in the sealing member 50. can be realized.

Also, for example, the chromaticity coordinates L3 of the third light are (x, y)=(0.28, 0.68), (x, y)=(0.2, 0 . 62), (x, y) = (0.08, 0.54), (x, y) = (0.07, 0.46), (x, y) = (0.14, 0.38) , (x,y)=(0.29,0.38), (x,y)=(0.41,0.58) and (x,y)=(0.28,0.68) points may be chromaticity coordinates located within a region surrounded by . Since the chromaticity coordinate area in such a case is a chromaticity coordinate in which the light color of yellowish green is limited, the light color of the mixed light of the first light and the second light is The additional adjustment width becomes larger.

The chromaticity coordinate range of the third light can be adjusted during implementation. For example, the chromaticity coordinate range of the third light is determined by the phosphors contained in the third fluorescent member 32, such as a silicate-based phosphor BOSE such as a green-emitting BOSE phosphor, a βSiAlON phosphor, a BaSiON phosphor, and the like. By using a single or a plurality of nitride-based phosphors, using a single or a plurality of nitride-based phosphors such as red-emitting CASN phosphors and SCASN phosphors, and combining these green-emitting phosphors and red-emitting phosphors , is feasible. A phosphor having a narrow band emission peak such as a KFS phosphor and an MFG phosphor may be used as the red light emitting phosphor.

Furthermore, to the combination of the green-emitting phosphor and the red-emitting phosphor, a yellow-emitting YAG phosphor that emits light in a wide wavelength band and has a relatively wider half-value width of the emission peak than the green-emitting phosphor is added for practical use. You can adjust above. The yellow light-emitting phosphor that emits light in a wide wavelength band to be added has a peak position of the emission spectrum of 500 nm or more and 540 nm or less, such as a LuAG phosphor or LSN phosphor, and the main emission intensity is in the wavelength range of 540 nm or more and 600 nm or less. In the case of a yellow-emitting phosphor that emits a certain light, the yellow-emitting phosphor can be used to adjust the chromaticity coordinates of the third light to a region of chromaticity coordinates where the yellowish green light color is restricted. preferred. As the phosphor contained in the third fluorescent member 32, the peak position of the emission spectrum of a LuAG phosphor, LSN phosphor, or the like is located in the range of 500 nm or more and 540 nm or less, and the main emission intensity is in the wavelength range of 540 nm or more and 600 nm or less. A combination of a yellow light-emitting phosphor that emits light and a red light-emitting phosphor such as a nitride-based phosphor such as CASN phosphor or SCASN phosphor may be used.

In addition, the phosphors contained in the third fluorescent member 32 include green-emitting phosphors such as a BOSE phosphor having a narrow half-value width of an emission peak and a βSiAlON phosphor, and a YAG phosphor and a LuAG phosphor having a wide half-value width of an emission peak. yellow-emitting phosphors such as CASN phosphors and SCASN phosphors may be combined with red-emitting phosphors.

Also, as shown in FIG. 3, the first light and the second light have chromaticity coordinates near the blackbody locus. As a result, the deviation of the first white light from the blackbody locus is reduced, and the mixing ratio of the third light for toning the second white light to the chromaticity coordinates of the blackbody locus can be reduced. Improves accuracy. Furthermore, when the first light and the second light have chromaticity coordinates near the blackbody locus, the chromaticity coordinates of the first white light are located in a region where the color deviation Duv is negative in a wide range of correlated color temperatures. do. Therefore, in order to adjust the color of the second white light to the light of the chromaticity coordinates of the blackbody locus, the chromaticity coordinates of the third light should be in a region where the color deviation Duv is greater than zero. In this specification, the chromaticity coordinates in the vicinity of the black body locus are the chromaticity coordinates of the region where the absolute value of the color deviation Duv is 3 or less. Color deviation Duv is calculated by the method described in JIS Z8725.

Also, the third light has an emission spectrum corresponding to the gamut area ratio of each of the first light and the second light. The emission spectrum of the third light may have at least two or more peaks derived from light emitted from the third fluorescent member 32 . The control unit 40 adjusts the ratio of the light amounts of the first light emitting unit 10, the second light emitting unit 20, and the third light emitting unit 30, so that the general color rendering index of the second white light becomes the average of the first white light. more than the color rendering index. The color gamut area ratio and the general color rendering index are calculated by the method described in JIS Z8726. The color gamut area ratio is an index for evaluating the vividness of the color rendering of light. As the color gamut area ratio of light increases, the color of the illuminated object appears more vivid. Also, the general color rendering index is an index representing the fidelity of color reproduction, that is, the color rendering properties. Light with a higher general color rendering index value has higher color rendering properties, and faithfully reproduces the color of an illuminated object.

Specifically, light with a color gamut area ratio value of more than 100 is light with high saturation that makes the color of the illuminated object look more vivid than the reference light. Depending on whether the first light and the second light are light with high saturation, the characteristics of the emission spectrum shapes of the first light and the second light change. Change. Therefore, when the emission spectrum of the third light has peaks corresponding to the characteristics of the emission spectrum shapes of the first light and the second light, the third light is mixed with the first white light. 2 The general color rendering index of white light is enhanced. Therefore, lighting device 100 can change the correlated color temperature of white light emitted along the chromaticity coordinates of the black body locus and at the same time improve the color rendering of the emitted white light.

For example, when the gamut area ratio of at least one of the first light and the second light is 100 or less, the emission spectrum of the third light has a peak at a wavelength of 520 nm or more and 540 nm or less and a peak at a wavelength of 620 nm or more and 650 nm or less. The peak at a wavelength of 520 nm or more and 540 nm or less and the peak at a wavelength of 620 nm or more and 650 nm or less in the emission spectrum of the third light are, for example, peaks derived from the light emission of the third fluorescent member 32 . When the color gamut area ratio of at least one of the first light and the second light is 100 or less, in the first white light, the light component with a wavelength of 520 nm or more and 540 nm or less and the light component with a wavelength of 620 nm or more and 650 nm or less are relatively tend to be less. Therefore, when the third light has such an emission spectrum, the general color rendering index of the second white light becomes equal to or higher than the general color rendering index of the first white light. In addition, the emission spectrum of the third light may have a peak derived from the emission of the third light emitting element 31 .

Also, for example, when the color gamut area ratio of each of the first light and the second light is greater than 100, the emission spectrum of the third light has a peak at wavelengths of 520 nm or more and 540 nm or less. A peak at a wavelength of 520 nm or more and 540 nm or less in the emission spectrum of the third light is, for example, a peak derived from light emission of the third fluorescent member 32 . When the color gamut area ratio of the first light and the second light is greater than 100, light components with wavelengths of 520 nm or more and 540 nm or less tend to be relatively small in the first white light. Therefore, when the third light has such an emission spectrum, the general color rendering index of the second white light becomes equal to or higher than the general color rendering index of the first white light.

As described above, the illumination device 100 according to the present embodiment includes the first light emitting unit 10 that emits the first light, the second light emitting unit 20 that emits the second light, and the third light emitting unit 30 that emits the third light. and a control unit 40 . The control unit 40 adjusts the light intensity of each of the first light emitting unit 10 , the second light emitting unit 20 and the third light emitting unit 30 . The correlated color temperature of the second light is lower than the correlated color temperature of the first light. Therefore, the first white light obtained by mixing the first light and the second light is toned to white light having a correlated color temperature between the correlated color temperature of the first light and the correlated color temperature of the second light. . Also, the chromaticity coordinates of the third light are the chromaticity coordinates of the position where the black body locus is sandwiched by a straight line connecting the chromaticity coordinates of the first light and the chromaticity coordinates of the second light. As a result, even if the chromaticity coordinates of the first white light deviate from the blackbody locus, the second white light obtained by mixing the first white light with the third light is the white light having the chromaticity coordinates on the blackbody locus. toned.

Also, the third light has an emission spectrum that is set according to the color gamut area ratios of the first light and the second light. Thereby, the emission spectrum of the third light can be set to an emission spectrum capable of enhancing the color rendering of the second white light according to the characteristics of the emission spectrum shapes of the first light and the second light. Therefore, when the third light has such an emission spectrum, the general color rendering index of the second white light obtained by mixing the third light with the first white light is increased. Therefore, lighting device 100 can change the correlated color temperature of white light emitted along the chromaticity coordinates of the black body locus and at the same time improve the color rendering of the emitted white light.

[Example]
Next, an example of the lighting device according to the present embodiment will be described. In addition, the example shown below is an example, and this invention is not limited only to the following examples. The lighting devices in the following embodiments have the same configuration as the lighting device 100 described above.

(1) Example 1
First, the illumination device 100 in Example 1 will be described. In the illumination device 100 in Example 1, the color gamut area ratio Ga of the first light and the second light are both 100 or less. In Example 1, the first light emitting element 11, the second light emitting element 21, and the third light emitting element 31 are all LEDs having an emission peak wavelength of about 450 nm. The first fluorescent member 12 is composed of a phosphor having an emission peak wavelength of approximately 560 nm and a phosphor having an emission peak wavelength of approximately 600 nm. The second fluorescent member 22 is composed of a phosphor having an emission peak wavelength of approximately 560 nm and a phosphor having an emission peak wavelength of approximately 610 nm. The third fluorescent member 32 is composed of a phosphor having an emission peak wavelength of approximately 520 nm and a phosphor having an emission peak wavelength of approximately 620 nm.

4A is a diagram showing the emission spectrum of the first light of the lighting device 100 in Example 1. FIG. 4B is a diagram showing the emission spectrum of the second light of the lighting device 100 in Example 1. FIG. 4C is a diagram showing the emission spectrum of the third light of the lighting device 100 in Example 1. FIG. Table 1 shows the chromaticity coordinates and the color deviation Duv of each of the first light, the second light, and the third light of the illumination device 100 in Example 1. These chromaticity coordinates, color deviation Duv, and emission spectrum are obtained from the compounding ratio of the phosphors contained in the first fluorescent member 12, the second fluorescent member 22, and the third fluorescent member 32, respectively, and the compounding amount in the sealing member 50. This is achieved by adjusting the The first light has a correlated color temperature of 6500 K, a general color rendering index Ra of 84, and a gamut area ratio Ga of 92. The second light has a correlated color temperature of 2700 K, a general color rendering index Ra of 82, and a gamut area ratio Ga of 94. As shown in FIG. 4C, the emission spectrum of the third light has peaks at wavelengths of 520 nm and 620 nm, which are derived from the emission of the third fluorescent member 32 .

In the illumination device 100 according to the first embodiment, the control unit 40 adjusts the ratio of the light amounts of the first light emitting unit 10, the second light emitting unit 20, and the third light emitting unit 30. FIG. The first white light is adjusted to white light having a correlated color temperature between the correlated color temperature of the first light and the correlated color temperature of the second light according to the mixing ratio of the first light and the second light. be. The second white light is mixed with the first white light and the third light to be adjusted to white light having chromaticity coordinates of the black body locus. When the correlated color temperature of the light emitted by the lighting device 100 in Example 1 is changed by adjusting the ratio of the light amounts of the first light emitting unit 10, the second light emitting unit 20, and the third light emitting unit 30, The results of color rendering index and color deviation Duv are shown in Table 2. Table 2 shows the general color rendering index Ra, the color rendering index R9, and the color deviation Duv for each of the first white light and the second white light. FIG. 4D is a diagram showing the color deviation Duv of light emitted by the illumination device 100 in Example 1. FIG. Specifically, FIG. 4D (a) shows the color deviation Duv when the first white light is toned to each correlated color temperature. (b) of FIG. 4D shows the color deviation Duv when the second white light is toned to each correlated color temperature. FIG. 4E is a diagram showing the color rendering index of light emitted by the illumination device 100 in Example 1. FIG. Specifically, in (a) of FIG. 4E, the color rendering index when the first white light is toned to each correlated color temperature (color rendering index R1 to R15 of each test color and average color rendering index Ra )It is shown. FIG. 4E (b) shows the color rendering index (color rendering index R1 to R15 and average color rendering index Ra of each test color) when the second white light is toned to each correlated color temperature. there is Note that the chromaticity coordinates of the first white light adjusted to the correlated color temperatures of 6500K and 6000K are on the positive side of Duv as in the case of the third light. It cannot be dimmed to white light in the chromaticity coordinates of the locus. In addition, since the chromaticity coordinates of the first white light adjusted to the correlated color temperature of 2700 K are the white light of the chromaticity coordinates of the substantially blackbody locus, there is no need to perform dimming. Therefore, for correlated color temperatures of 6500K, 6000K and 2700K, the result of white light in which the third light is not mixed with the first white light is shown as the result of the second white light.

As shown in Table 2 and FIG. 4D, the first white light has a positive or negative Duv value at any correlated color temperature. That is, the first white light that is toned by only two light emitting units cannot change the correlated color temperature along the chromaticity coordinates of the black body locus. On the other hand, the second white light has a correlated color temperature in the range of 3000K or more and 5000K or less and Duv is 0.0. That is, the second white light obtained by mixing the first white light with the third light can change the correlated color temperature along the chromaticity coordinates of the blackbody locus within the correlated color temperature range of 3000K or more and 5000K or less.

Moreover, as shown in Table 2, Ra and R9 of the second white light obtained by mixing the first white light with the third light are equal to or higher than Ra and R9 of the first white light. Further, as shown in FIG. 4E, in the correlated color temperature range of 3000K to 5000K, the color rendering index of each color including Ra and R9 of the second white light is also higher than the color rendering index of the first white light. and the numerical difference between the color rendering indices of each color has become smaller.

Therefore, the illumination device 100 according to the first embodiment can change the correlated color temperature of the white light emitted along the chromaticity coordinates of the black body locus and at the same time improve the color rendering properties of the emitted white light.

(2) Example 2
Next, the illumination device 100 in Example 2 will be described. In the illumination device 100 according to the second embodiment, the color gamut area ratio Ga of the first light is greater than 100, and the color gamut area ratio Ga of the second light is 100 or less. In Example 2, the first light emitting element 11, the second light emitting element 21, and the third light emitting element 31 are all LEDs having an emission peak wavelength of about 450 nm. The first fluorescent member 12 is composed of a phosphor with an emission peak wavelength of about 520 nm, a phosphor with an emission peak wavelength of about 560 nm, and a phosphor with an emission peak wavelength of about 620 nm. The second fluorescent member 22 is composed of a phosphor having an emission peak wavelength of approximately 560 nm and a phosphor having an emission peak wavelength of approximately 610 nm. The third fluorescent member 32 is composed of a phosphor having an emission peak wavelength of approximately 520 nm and a phosphor having an emission peak wavelength of approximately 620 nm.

FIG. 5A is a diagram showing the emission spectrum of the first light of the lighting device 100 in Example 2. FIG. FIG. 5B is a diagram showing the emission spectrum of the second light of the lighting device 100 in Example 2. FIG. FIG. 5C is a diagram showing the emission spectrum of the third light of the lighting device 100 in Example 2. FIG. Table 3 shows the chromaticity coordinates and the color deviation Duv of each of the first light, the second light, and the third light of the illumination device 100 in Example 2. These chromaticity coordinates, color deviation Duv, and emission spectrum are obtained from the compounding ratio of the phosphors contained in the first fluorescent member 12, the second fluorescent member 22, and the third fluorescent member 32, respectively, and the compounding amount in the sealing member 50. This is achieved by adjusting the The first light has a correlated color temperature of 6500 K, a general color rendering index Ra of 94, and a gamut area ratio Ga of 107. The second light has a correlated color temperature of 2700 K, a general color rendering index Ra of 82, and a gamut area ratio Ga of 94. As shown in FIG. 5C, the emission spectrum of the third light has peaks at wavelengths of 520 nm and 620 nm, which are derived from the emission of the third fluorescent member 32 .

As in the first embodiment, the correlated color temperature of the light emitted by the illumination device 100 in the second embodiment is adjusted by adjusting the ratio of the light amounts of the first light emitting unit 10, the second light emitting unit 20, and the third light emitting unit 30. Table 4 shows the results of the color rendering index and the color deviation Duv when . Table 4 shows the general color rendering index Ra, the color rendering index R9, and the color deviation Duv for each of the first white light and the second white light. FIG. 5D is a diagram showing the color deviation Duv of light emitted by the illumination device 100 in Example 2. FIG. Specifically, (a) of FIG. 5D shows the color deviation Duv when the first white light is toned to each correlated color temperature. (b) of FIG. 5D shows the color deviation Duv when the second white light is toned to each correlated color temperature. The chromaticity coordinates of the first white light adjusted to the correlated color temperature of 6500 K are on the positive side of Duv, like the third light. Cannot be dimmed to white light with chromaticity coordinates. In addition, since the chromaticity coordinates of the first white light adjusted to the correlated color temperature of 2700 K are the white light of the chromaticity coordinates of the substantially blackbody locus, there is no need to perform dimming. Therefore, for correlated color temperatures of 6500K and 2700K, the result of white light in which the third light is not mixed with the first white light is shown as the result of the second white light.

As shown in Table 4 and FIG. 5D, the first white light has a positive or negative Duv value at any correlated color temperature. That is, the first white light that is toned by only two light emitting units cannot change the correlated color temperature along the chromaticity coordinates of the blackbody locus. On the other hand, the second white light has a correlated color temperature of 3000K or more and 6000K or less and Duv is 0.0. That is, the second white light obtained by mixing the first white light with the third light can change the correlated color temperature along the chromaticity coordinates of the black body locus within the correlated color temperature range of 3000K or more and 6000K or less.

Further, as shown in Table 4, Ra of the second white light obtained by mixing the first white light with the third light is equal to or higher than Ra of the first white light. R9 of the second white light is greater than or equal to R9 of the first white light except when the correlated color temperature is 6000K.

Therefore, the illumination device 100 according to the second embodiment can change the correlated color temperature of the white light emitted along the chromaticity coordinates of the black body locus and simultaneously improve the color rendering properties of the emitted white light.

(3) Example 3
Next, the illumination device 100 in Example 3 will be described. In the illumination device 100 of Example 3, the color gamut area ratio Ga of the first light is 100 or less, and the color gamut area ratio Ga of the second light is greater than 100. In Example 3, the first light emitting element 11, the second light emitting element 21, and the third light emitting element 31 are all LEDs having an emission peak wavelength of about 450 nm. The first fluorescent member 12 is composed of a phosphor having an emission peak wavelength of approximately 560 nm and a phosphor having an emission peak wavelength of approximately 600 nm. The second fluorescent member 22 is composed of a phosphor having an emission peak wavelength of approximately 520 nm, a phosphor having an emission peak wavelength of approximately 560 nm, and a phosphor having an emission peak wavelength of approximately 625 nm. The third fluorescent member 32 is composed of a phosphor having an emission peak wavelength of approximately 520 nm and a phosphor having an emission peak wavelength of approximately 620 nm.

FIG. 6A is a diagram showing the emission spectrum of the first light of the illumination device 100 in Example 3. FIG. FIG. 6B is a diagram showing the emission spectrum of the second light of the illumination device 100 in Example 3. FIG. FIG. 6C is a diagram showing the emission spectrum of the third light of the illumination device 100 in Example 3. FIG. Table 5 shows the chromaticity coordinates and the color deviation Duv of each of the first light, the second light, and the third light of the illumination device 100 in Example 3. These chromaticity coordinates, color deviation Duv, and emission spectrum are obtained from the compounding ratio of the phosphors contained in the first fluorescent member 12, the second fluorescent member 22, and the third fluorescent member 32, respectively, and the compounding amount in the sealing member 50. This is achieved by adjusting the The first light has a correlated color temperature of 6500 K, a general color rendering index Ra of 84, and a gamut area ratio Ga of 92. The second light has a correlated color temperature of 2700 K, a general color rendering index Ra of 95, and a gamut area ratio Ga of 102. As shown in FIG. 6C, the emission spectrum of the third light has peaks at wavelengths of 520 nm and 620 nm, which are derived from the emission of the third fluorescent member 32 .

As in the first embodiment, the correlated color temperature of the light emitted by the illumination device 100 in the third embodiment is adjusted by adjusting the ratio of the light amounts of the first light emitting unit 10, the second light emitting unit 20, and the third light emitting unit 30. Table 6 shows the results of color rendering index and color deviation Duv when . Table 6 shows the general color rendering index Ra, the color rendering index R9, and the color deviation Duv for each of the first white light and the second white light. FIG. 6D is a diagram showing the color deviation Duv of light emitted by the illumination device 100 in Example 3. FIG. Specifically, (a) of FIG. 6D shows the color deviation Duv when the first white light is toned to each correlated color temperature. (b) of FIG. 6D shows the color deviation Duv when the second white light is toned to each correlated color temperature. Note that the chromaticity coordinates of the first white light adjusted to the correlated color temperatures of 6500K and 6000K are on the positive side of Duv as in the case of the third light. It cannot be dimmed to white light in the chromaticity coordinates of the locus. In addition, since the chromaticity coordinates of the first white light adjusted to the correlated color temperature of 2700 K are the white light of the chromaticity coordinates of the black body locus, there is no need to perform dimming. Therefore, for correlated color temperatures of 6500K, 6000K and 2700K, the result of white light in which the third light is not mixed with the first white light is shown as the result of the second white light.

As shown in Table 6 and FIG. 6D, the first white light has a positive or negative Duv value, except for the correlated color temperature of 2700K. That is, the first white light that is toned by only two light emitting units cannot change the correlated color temperature along the chromaticity coordinates of the black body locus. On the other hand, the second white light has a correlated color temperature in the range of 2700K or more and 5000K or less and Duv is 0.0. That is, the second white light obtained by mixing the first white light with the third light can change the correlated color temperature along the chromaticity coordinates of the black body locus within the correlated color temperature range of 2700K or more and 5000K or less.

Further, as shown in Table 6, Ra of the second white light obtained by mixing the first white light with the third light is equal to or higher than Ra of the first white light. R9 of the second white light is greater than or equal to R9 of the first white light.

Therefore, the illumination device 100 according to the third embodiment can change the correlated color temperature of the white light emitted along the chromaticity coordinates of the black body locus and simultaneously improve the color rendering properties of the emitted white light.

(4) Example 4
Next, the illumination device 100 in Example 4 will be described. In the illumination device 100 of Example 4, the color gamut area ratio Ga of each of the first light and the second light is greater than 100, and the general color rendering index Ra is greater than 90. In other words, the illumination device 100 according to the fourth embodiment includes the first light emitting unit 10 and the second light emitting unit 20 with high color rendering. In Example 4, the first light emitting element 11, the second light emitting element 21, and the third light emitting element 31 are all LEDs having an emission peak wavelength of about 450 nm. The first fluorescent member 12 is composed of a phosphor with an emission peak wavelength of about 520 nm, a phosphor with an emission peak wavelength of about 560 nm, and a phosphor with an emission peak wavelength of about 620 nm. The second fluorescent member 22 is composed of a phosphor having an emission peak wavelength of approximately 520 nm, a phosphor having an emission peak wavelength of approximately 560 nm, and a phosphor having an emission peak wavelength of approximately 625 nm. The third fluorescent member 32 is made of a phosphor having an emission peak wavelength of approximately 520 nm.

FIG. 7A is a diagram showing the emission spectrum of the first light of the lighting device 100 in Example 4. FIG. FIG. 7B is a diagram showing the emission spectrum of the second light of the lighting device 100 in Example 4. FIG. FIG. 7C is a diagram showing the emission spectrum of the third light of the lighting device 100 in Example 4. FIG. Table 7 shows the chromaticity coordinates and the color deviation Duv of each of the first light, the second light, and the third light of the illumination device 100 in Example 4. These chromaticity coordinates, color deviation Duv, and emission spectrum are obtained from the compounding ratio of the phosphors contained in the first fluorescent member 12, the second fluorescent member 22, and the third fluorescent member 32, respectively, and the compounding amount in the sealing member 50. This is achieved by adjusting the The first light has a correlated color temperature of 6500K, a general color rendering index Ra of 93, and a gamut area ratio Ga of 106. The second light has a correlated color temperature of 2700K, a general color rendering index Ra of 96, and a gamut area ratio Ga of 102. As shown in FIG. 7C, the emission spectrum of the third light has a peak derived from the emission of the third fluorescent member 32 at a wavelength of 520 nm.

Note that Table 7 describes the color deviation Duv of the third light having a value larger than the value generally used. Normally, the color deviation Duv is often calculated for the range of light colors used as common white light, which has a value of approximately ±20. Colors can be calculated. In this specification, even if the values of the color deviation Duv are in a wider range than usual, numerical values are described so that comparison can be made in a unified manner.

As in the first embodiment, the correlated color temperature of the light emitted by the illumination device 100 in the fourth embodiment is adjusted by adjusting the ratio of the light amounts of the first light emitting unit 10, the second light emitting unit 20, and the third light emitting unit 30. Table 8 shows the results of color rendering index and color deviation Duv when . Table 8 shows the general color rendering index Ra, the color rendering index R9, and the color deviation Duv for each of the first white light and the second white light. FIG. 7D is a diagram showing the color deviation Duv of light emitted by the illumination device 100 in Example 4. FIG. Specifically, (a) of FIG. 7D shows the color deviation Duv when the first white light is toned to each correlated color temperature. (b) of FIG. 7D shows the color deviation Duv when the second white light is toned to each correlated color temperature. The chromaticity coordinates of the first white light adjusted to the correlated color temperature of 6500 K are on the positive side of Duv, like the third light. Cannot be dimmed to white light with chromaticity coordinates. In addition, since the chromaticity coordinates of the first white light adjusted to the correlated color temperature of 2700 K are the white light of the chromaticity coordinates of the black body locus, there is no need to perform dimming. Therefore, for correlated color temperatures of 6500K and 2700K, the result of white light in which the third light is not mixed with the first white light is shown as the result of the second white light.

As shown in Table 8 and FIG. 7D, the first white light has a positive or negative Duv value, except for the correlated color temperature of 2700K. That is, the first white light that is toned by only two light emitting units cannot change the correlated color temperature along the chromaticity coordinates of the blackbody locus. On the other hand, the second white light has a correlated color temperature in the range of 2700K or more and 6000K or less and Duv is 0.0. That is, the second white light obtained by mixing the first white light with the third light can change the correlated color temperature along the chromaticity coordinates of the black body locus within the correlated color temperature range of 2700K or more and 6000K or less.

Further, as shown in Table 8, Ra of the second white light obtained by mixing the first white light with the third light is equal to or higher than Ra of the first white light. The R9 of the second white light is greater than or equal to the R9 of the first white light except when the correlated color temperature is 3000K and 3500K.

Therefore, the illumination device 100 according to the fourth embodiment can change the correlated color temperature of the white light emitted along the chromaticity coordinates of the black body locus and simultaneously improve the color rendering properties of the emitted white light.

(5) Example 5
Next, the illumination device 100 in Example 5 will be described. In the illumination device 100 of Example 5, the color gamut area ratio Ga of each of the first light and the second light is greater than 100, and the general color rendering index Ra is 90 or less. In other words, the illumination device 100 according to the fifth embodiment includes the first light emitting unit 10 and the second light emitting unit 20 with high saturation. In Example 5, the first light emitting element 11, the second light emitting element 21, and the third light emitting element 31 are all LEDs having an emission peak wavelength of about 450 nm. The first fluorescent member 12 is composed of a phosphor having an emission peak wavelength of approximately 520 nm and a phosphor having an emission peak wavelength of approximately 620 nm. The second fluorescent member 22 is composed of a phosphor having an emission peak wavelength of approximately 520 nm and a phosphor having an emission peak wavelength of approximately 620 nm. The third fluorescent member 32 is made of a phosphor having an emission peak wavelength of approximately 520 nm.

FIG. 8A is a diagram showing the emission spectrum of the first light of the lighting device 100 in Example 5. FIG. FIG. 8B is a diagram showing the emission spectrum of the second light of the lighting device 100 in Example 5. FIG. 8C is a diagram showing the emission spectrum of the third light of the lighting device 100 in Example 5. FIG. Table 9 shows the chromaticity coordinates and color deviation Duv of each of the first light, the second light, and the third light of the illumination device 100 in Example 5. These chromaticity coordinates, color deviation Duv, and emission spectrum are obtained from the compounding ratio of the phosphors contained in the first fluorescent member 12, the second fluorescent member 22, and the third fluorescent member 32, respectively, and the compounding amount in the sealing member 50. This is achieved by adjusting the The first light has a correlated color temperature of 6500 K, a general color rendering index Ra of 84, and a gamut area ratio Ga of 116. The second light has a correlated color temperature of 2700K, a general color rendering index Ra of 84, and a gamut area ratio Ga of 109. As shown in FIG. 8C, the emission spectrum of the third light has a peak derived from the emission of the third fluorescent member 32 at a wavelength of 520 nm.

As in the first embodiment, the correlated color temperature of the light emitted by the illumination device 100 in the fifth embodiment is adjusted by adjusting the ratio of the light amounts of the first light emitting unit 10, the second light emitting unit 20, and the third light emitting unit 30. Table 10 shows the results of color rendering index and color deviation Duv when . Table 10 shows the general color rendering index Ra, the color rendering index R9, and the color deviation Duv for each of the first white light and the second white light. FIG. 8D is a diagram showing the color deviation Duv of light emitted by the illumination device 100 in Example 5. FIG. Specifically, FIG. 8D (a) shows the color deviation Duv when the first white light is toned to each correlated color temperature. (b) of FIG. 8D shows the color deviation Duv when the second white light is toned to each correlated color temperature. The chromaticity coordinates of the first white light adjusted to the correlated color temperatures of 6500K and 2700K are the white light of the chromaticity coordinates of the black body locus, and thus there is no need for dimming. Therefore, for correlated color temperatures of 6500K and 2700K, the result of white light in which the third light is not mixed with the first white light is shown as the result of the second white light.

As shown in Table 10 and FIG. 8D, the first white light has a negative value of Duv except when the correlated color temperature is 2700K and 6500K. That is, the first white light that is toned by only two light emitting units cannot change the correlated color temperature along the chromaticity coordinates of the black body locus. On the other hand, the second white light has a correlated color temperature of 2700K or more and 6500K or less and Duv is 0.0. That is, the second white light obtained by mixing the first white light with the third light can change the correlated color temperature along the chromaticity coordinates of the black body locus within the correlated color temperature range of 2700K or more and 6500K or less. Thus, when the color deviation Duv of the first light and the second light is 0 or less and the color deviation Duv of the third light is greater than 0, the correlated color temperature of the first light and the correlated color of the second light The correlated color temperature can be varied along the chromaticity coordinates of the blackbody locus over the entire range between temperatures.

Further, as shown in Table 10, Ra of the second white light obtained by mixing the first white light with the third light is equal to or higher than Ra of the first white light. R9 of the second white light is greater than or equal to R9 of the first white light.

Therefore, the illumination device 100 according to the fifth embodiment can change the correlated color temperature of the white light emitted along the chromaticity coordinates of the black body locus and at the same time improve the color rendering properties of the emitted white light.

As described above, in the lighting device 100 according to the first to third embodiments, the color gamut area ratio Ga of at least one of the first light and the second light is 100 or less. Furthermore, in the illumination device 100 according to the first to third embodiments, the emission spectrum of the third light has a peak at wavelengths of 520 nm to 540 nm and a peak at wavelengths of 620 nm to 650 nm. In addition, in the lighting device 100 in Examples 4 and 5, the color gamut area ratio Ga of each of the first light and the second light is greater than 100, and the emission spectrum of the third light has a peak at a wavelength of 520 nm or more and 540 nm or less. have. As described above, in the lighting device 100 according to the first to fifth embodiments, the third light having the emission spectrum corresponding to the gamut area ratio Ga of the first light and the second light is mixed with the first white light. be. As a result, a lighting device is realized that can change the correlated color temperature of white light emitted along the chromaticity coordinates of the blackbody locus and at the same time improve the color rendering of the emitted white light.

(Other embodiments)
Although the illumination device according to the present invention has been described above based on the embodiments, the present invention is not limited to the above embodiments.

For example, in the above embodiments, the first light emitting element 11, the second light emitting element 21 and the third light emitting element 31 are LEDs that emit blue light, but they are not limited to this. The first light emitting element 11, the second light emitting element 21, and the third light emitting element 31 may include an LED that emits blue light and an LED that emits light of colors other than blue. Also, the first light emitting element 11, the second light emitting element 21, and the third light emitting element 31 may be LEDs that emit ultraviolet light.

Also, for example, in the above-described embodiment, the first light emitting unit 10, the second light emitting unit 20, and the third light emitting unit 30 are mounted on the same substrate 60, but the present invention is not limited to this. The first light emitting unit 10, the second light emitting unit 20, and the third light emitting unit 30 may be mounted on separate substrates. Further, a plurality of lighting devices each individually including the first light emitting unit 10, the second light emitting unit 20, and the third light emitting unit 30 may be combined.

Further, for example, in the above embodiment, the chromaticity coordinates of the third light are the chromaticity coordinates of the region where the color deviation Duv is greater than 0 in the CIE xy chromaticity diagram, but the present invention is not limited to this. When the straight line connecting the chromaticity coordinates of the first light and the chromaticity coordinates of the second light exists in an area where the color deviation Duv is greater than 0, the chromaticity coordinates of the third light are such that the color deviation Duv is negative. , the second white light is toned to the white light with the chromaticity coordinates of the black body locus.

In addition, forms obtained by applying various modifications that a person skilled in the art can come up with to the above-described embodiments, and realized by arbitrarily combining the constituent elements and functions of the embodiments without departing from the scope of the present invention. Also included in the present invention.

10 First Light Emitting Part 11 First Light Emitting Element 12 First Fluorescent Member 20 Second Light Emitting Part 21 Second Light Emitting Element 22 Second Fluorescent Member 30 Third Light Emitting Part 31 Third Light Emitting Element 32 Third Fluorescent Member 40 Control Part 100 Illumination Device

Claims (7)

a first light emitting unit that emits the first light;
a second light emitting unit that emits a second light having a correlated color temperature lower than that of the first light;
A third emission that emits a third light having chromaticity coordinates at a position sandwiching the black body radiation locus by a straight line connecting the chromaticity coordinates of the first light and the chromaticity coordinates of the second light in the CIE xy chromaticity diagram. Department and
A control unit that adjusts the light intensity of each of the first light emitting unit, the second light emitting unit, and the third light emitting unit,
At least one of the first light and the second light has a gamut area ratio of 100 or less,
The emission spectrum of the third light has a peak at a wavelength of 520 nm or more and 540 nm or less and a peak at a wavelength of 620 nm or more and 650 nm or less.
lighting device. a first light emitting unit that emits the first light;
a second light emitting unit that emits a second light having a correlated color temperature lower than that of the first light;
A third emission that emits a third light having chromaticity coordinates at a position sandwiching the black body radiation locus by a straight line connecting the chromaticity coordinates of the first light and the chromaticity coordinates of the second light in the CIE xy chromaticity diagram. Department and
A control unit that adjusts the light intensity of each of the first light emitting unit, the second light emitting unit, and the third light emitting unit,
a color gamut area ratio of each of the first light and the second light is greater than 100;
The emission spectrum of the third light has a peak at a wavelength of 520 nm or more and 540 nm or less.
lighting device. The first light emitting unit has a first light emitting element and a first fluorescent member for wavelength-converting at least part of the light emitted by the first light emitting element, and the light emitted by the first light emitting element and the mixing the wavelength-converted light with the first fluorescent member to emit the first light;
The second light emitting unit has a second light emitting element and a second fluorescent member that converts the wavelength of at least part of the light emitted by the second light emitting element, and the light emitted by the second light emitting element and the mixing the wavelength-converted light with the second fluorescent member to emit the second light;
The third light emitting unit has a third light emitting element and a third fluorescent member that converts the wavelength of at least part of the light emitted by the third light emitting element, and the light emitted by the third light emitting element and the mixing the wavelength-converted light with the third fluorescent member to emit the third light;
In the CIE xy chromaticity diagram, at least part of a straight line connecting the chromaticity coordinates of the first light and the chromaticity coordinates of the second light exists in a region where the color deviation Duv is less than 0;
the chromaticity coordinates of the third light are chromaticity coordinates located in a region where the color deviation Duv is greater than 0 in the CIE xy chromaticity diagram;
The emission spectrum of the third light has at least two or more peaks derived from the light emitted from the third fluorescent member,
3. A lighting device according to claim 1 or 2 . The chromaticity coordinates of the third light are chromaticity coordinates located in a region where the color deviation Duv is greater than 0 in the CIE xy chromaticity diagram.
4. A lighting device according to any one of claims 1 to 3 . The chromaticity coordinates of the third light are chromaticity coordinates located in a region where the color deviation Duv is 10 or more in the CIE xy chromaticity diagram.
5. A lighting device according to any one of claims 1 to 4 . The chromaticity coordinates of the third light are (x, y) = (0.28, 0.68), (x, y) = (0.2, 0.62), ( x, y) = (0.08, 0.54), (x, y) = (0.07, 0.46), (x, y) = (0.14, 0.38), (x, y) = (0.29, 0.38), (x, y) = (0.51, 0.48) and (x, y) = (0.28, 0.68)
is the chromaticity coordinates located within the area bounded by the points of
6. A lighting device according to any one of claims 1 to 5 . The chromaticity coordinates of the third light are (x, y) = (0.28, 0.68), (x, y) = (0.2, 0.62), ( x, y) = (0.08, 0.54), (x, y) = (0.07, 0.46), (x, y) = (0.14, 0.38), (x, y) = (0.29, 0.38), (x, y) = (0.41, 0.58) and (x, y) = (0.28, 0.68)
is the chromaticity coordinates located within the area bounded by the points of
6. A lighting device according to any one of claims 1 to 5 .

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