JP2022178695A - Illumination system, and illumination method - Google Patents

Abstract

To provide an illumination system capable of adjusting the chromaticity of output light and capable of achieving output light that has a high general color rendering index Ra, and an illumination method.SOLUTION: A control unit included in the illumination system achieves output light that has the chromaticity values in the first region of a triangle whose vertices are the three closest points to the blackbody locus among the four points by emitting from 3 out of the 4 light sources corresponding to the 3 vertices of the first region and achieves output light that has chromaticity values in the second triangular area excluding the first area from the rectangular area by emitting 3 of the 4 light sources corresponding to the 3 vertices of the second region.SELECTED DRAWING: Figure 2

Description

The present invention relates to lighting systems and lighting methods.

2. Description of the Related Art Conventionally, various techniques have been proposed for adjusting the color of output light from lighting devices (see, for example, Patent Document 1).

JP 2009-123429 A

The present invention provides an illumination system and illumination method capable of adjusting the chromaticity of output light that can achieve output light with a high general color rendering index Ra.

An illumination system according to an aspect of the present invention includes a control unit that controls four light sources that emit light with different chromaticity values, and corresponds to the chromaticity values of the light emitted by the four light sources on chromaticity coordinates. A quadrangular region with the four points as vertices includes at least a part of the chromaticity range of the light source color defined in JISZ9112, and the control unit determines that the distance to the blackbody locus among the four points is By emitting output light having chromaticity values within a triangular first region with the three closest points as vertices, by emitting three light sources among the four light sources corresponding to the three vertices of the first region. output light having a chromaticity value within a second triangular region obtained by excluding the first region from the quadrangular region is emitted from three of the four light sources corresponding to the three vertices of the second region. It is realized by emitting light from the light source.

An illumination method according to an aspect of the present invention includes a control step of controlling four light sources that emit light with different chromaticity values, and corresponds to the chromaticity values of the light emitted by the four light sources on chromaticity coordinates. The quadrangular area with the four points as vertices includes at least part of the chromaticity range of the light source color defined in JISZ9112, and in the control step, the distance to the black body locus among the four points emitting output light having chromaticity values within a triangular first region whose vertices are the upper three points closest to and output light having chromaticity values within a second triangular region obtained by excluding the first region from the quadrangular region is output from the four light sources corresponding to the three vertices of the second region. This is achieved by emitting light from two light sources.

A program according to an aspect of the present invention is a program for causing a computer to execute the lighting method.

ADVANTAGE OF THE INVENTION According to this invention, the illumination system and illumination method which can adjust the chromaticity of output light which can implement|achieve output light with high general color rendering index Ra are provided.

FIG. 1 is a block diagram showing a functional configuration of a lighting system according to Embodiment 1. FIG. FIG. 2 is a diagram showing chromaticity coordinates in which chromaticity values of four light sources provided in the lighting system according to Embodiment 1 are plotted. FIG. 3 is a diagram showing the general color rendering index Ra of output light obtained by the chromaticity control method (control example 1) in the lighting system according to the first embodiment. FIG. 4 is a diagram showing chromaticity coordinates in which points related to Control Example 2 of the lighting system according to Embodiment 1 are plotted. FIG. 5 is a diagram showing a simulation result of the luminous flux of output light and the general color rendering index Ra realized by Control Example 2 of Embodiment 1. In FIG. FIG. 6 is a block diagram showing a functional configuration of a lighting system according to Embodiment 2. FIG. FIG. 7 is a diagram showing chromaticity coordinates in which chromaticity values of four light sources provided in the illumination system according to Embodiment 2 are plotted. FIG. 8 is a diagram showing the general color rendering index Ra of output light obtained by the chromaticity control method (control example 1) in the lighting system according to the second embodiment. FIG. 9 is a diagram showing chromaticity coordinates in which points related to Control Example 2 of the lighting system according to Embodiment 2 are plotted.

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. Further, among the constituent elements in the following embodiments, constituent elements not described in independent claims will be described as optional constituent elements.

Each figure is a schematic diagram and is not necessarily strictly illustrated. Moreover, in each figure, the same code|symbol is attached|subjected with respect to substantially the same structure, and the overlapping description may be abbreviate|omitted or simplified.

(Embodiment 1)
[Constitution]
First, the configuration of the lighting system according to Embodiment 1 will be described. FIG. 1 is a block diagram showing a functional configuration of a lighting system according to Embodiment 1. FIG.

The lighting system 10 independently controls the blue light source 42b, the green light source 42g, the red light source 42r, and the blue-green light source 42bg included in the light source unit 42 included in the lighting device 40, so that the lighting device 40 can be used by the user. is a system that can emit light with a desired chromaticity of In other words, the lighting system 10 is a system that supports the chromaticity adjustment function of the lighting device 40 . The lighting system 10 includes an input device 20 , a control device 30 and a lighting device 40 . Note that the lighting system 10 may include a plurality of lighting devices 40 for one control device 30 .

The input device 20 receives input from the user for specifying chromaticity. The input device 20 is, for example, a portable information terminal such as a smart phone or a tablet terminal, but may be a stationary information terminal fixedly installed on a wall or the like. The input device 20 may be realized by installing an application program corresponding to the lighting system 10 in a general-purpose device, or may be a dedicated device for the lighting system 10 .

The control device 30 controls the lighting device 40 to emit light with the chromaticity input to the input device 20 . The control device 30 includes a control section 31 and a storage section 32 . Note that the input device 20 and the control device 30 may be realized as one integrated device.

The control unit 31 controls light emission of the lighting device 40 . Specifically, the control unit 31 can adjust the chromaticity of the light emitted by the lighting device 40 by transmitting a control signal to the lighting device 40 . For example, the control unit 31 transmits the control signal to the lighting device 40 through wireless communication, but may transmit the control signal to the lighting device 40 through wired communication. The control unit 31 is implemented by, for example, a microcomputer, but may be implemented by a processor. The functions of the control unit 31 are realized by executing a computer program stored in the storage unit 32 by a microcomputer or processor that constitutes the control unit 31 .

The storage unit 32 is a storage device that stores computer programs executed by the control unit 31 and various information necessary for controlling the lighting device 40 . The storage unit 32 is specifically implemented by a semiconductor memory or the like.

The lighting device 40 is installed, for example, indoors to illuminate the indoor space. The illumination device 40 is, for example, a ceiling light, but may be another illumination device such as a spotlight or a downlight. The illumination device 40 includes a dimming circuit 41 and a light source section 42 . The light source unit 42 includes a red light source 42r, a green light source 42g, a blue light source 42b, and a blue-green light source 42bg.

The dimming circuit 41 is a circuit that supplies power to the light source unit 42 according to a control signal transmitted from the control device 30 (control unit 31). The dimming circuit 41 includes, for example, a chopper control circuit. The control unit 31 changes the current supplied to the light source unit 42 by switching the switching element included in the dimming circuit 41 (chopper control circuit) according to the control signal. The light control circuit 41 can independently supply power (current) to each of the blue light source 42b, the green light source 42g, the red light source 42r, and the blue-green light source 42bg of the light source section 42. That is, the dimming circuit 41 can independently dim the red light source 42r, the green light source 42g, the blue light source 42b, and the blue-green light source 42bg included in the light source section 42. FIG.

The blue light source 42b is a light source that emits blue light. The blue light source 42b emits, for example, blue light with an emission peak wavelength of 380 nm or more and 480 nm or less (more specifically, includes blue and violet light). The blue light source 42b is specifically a light-emitting module using a blue LED, but the specific aspect of the blue light source 42b is not particularly limited.

The green light source 42g is a light source that emits green light. The green light source 42g emits, for example, green light with an emission peak wavelength of 480 nm or more and 580 nm or less (more specifically, green-blue, blue-green, green, and yellowish-green light is included). The green light source 42g is specifically a light-emitting module using a green LED, but the specific aspect of the green light source 42g is not particularly limited.

The red light source 42r is a light source that emits red light. The red light source 42r emits red light with an emission peak wavelength of 600 nm or more and 680 nm or less, for example. The red light source 42r is specifically a light-emitting module using a red LED, but the specific aspect of the red light source 42r is not particularly limited.

The blue-green light source 42bg is a light source that emits blue-green light (blue-green is sometimes expressed as royal blue, etc.), and is an example of another light source or another blue light source. The blue-green light source 42bg emits blue-green light (blue light with a longer wavelength than the blue light source 42b) with an emission peak wavelength of 465 nm or more and 490 nm or less, for example. The bluish-green light source 42bg is specifically a light-emitting module using an LED that emits bluish-green, but the specific aspect of the bluish-green light source 42bg is not particularly limited.

[Chromaticity control example 1]
When controlling the chromaticity of the output light of the lighting device 40, the illumination system 10 selectively causes the blue light source 42b, the green light source 42g, the red light source 42r, and the blue-green light source 42bg to emit light. Color rendering can be improved. The output light is light obtained by synthesizing at least one of the light emitted by the red light source 42r, the light emitted by the green light source 42g, the light emitted by the blue light source 42b, and the light emitted by the blue-green light source 42bg. It means the light finally emitted from 40 . Chromaticity control example 1 of the lighting system 10 will be described below with reference to a chromaticity diagram (chromaticity coordinates). FIG. 2 is a diagram showing chromaticity coordinates in which chromaticity values of the red light source 42r, the green light source 42g, the blue light source 42b, and the blue-green light source 42bg are plotted. The chromaticity coordinates in FIG. 2 indicate the color space defined in CIE1931.

In the chromaticity coordinates of FIG. 2, a point B1 indicating the chromaticity value of the blue light emitted by the blue light source 42b, a point G indicating the chromaticity value of the green light emitted by the green light source 42g, and the color of the red light emitted by the red light source 42r. A point R indicating the chromaticity value and a point B2 indicating the fourth chromaticity value of the blue-green light emitted by the blue-green light source 42bg are shown.

On the chromaticity coordinates, a quadrangular area with points B1, G, R, and B2 as vertices includes at least part of the chromaticity range of the light source color defined in JISZ9112. Here, the light source color means five types of daylight color (D), daylight white (N), white (W), warm white (WW), and light bulb color (L). The degree ranges are the five roughly parallelogram-shaped regions near the blackbody locus in FIG. Specifically, the quadrangular region having points B1, G, R, and B2 as vertices is daylight (D), daylight white (N), white (W), and warm white (WW). It includes the entire chromaticity range and part of the chromaticity range of incandescent light (L). The illumination system 10 is capable of realizing output light having chromaticity values within a rectangular region with points B1, G, R, and B2 as vertices, and the output light that the illumination system 10 can achieve. can be said to have a relatively wide chromaticity range.

The illumination system 10 divides the quadrilateral region into a first triangular region having points G, R, and B2 as vertices, and a second triangular region having points B1, R, and B2 as vertices. The color rendering of the output light can be improved by adjusting the chromaticity by dividing it into regions. When dividing a square region into two triangular regions, there are two ways of dividing. A triangular area whose vertices are the top three points closest to the body trajectory is defined as the first area, and a triangular area obtained by excluding the first area from the quadrilateral area is defined as the second area. Note that the distance from the point B1 to the blackbody locus means, for example, the average value of the distances from the point B1 to each of a plurality of points when the blackbody locus is regarded as a set of a plurality of points. The same applies to the distance from point G, point R, and point B2 to the black body locus.

For example, when the point indicating the chromaticity value desired by the user input to the input device 20 is located within the first region, the control unit 31 of the control device 30 does not cause the blue light source 42b to emit light, and the green light source 42g, Output light having a chromaticity value desired by the user is realized by causing the three light sources of the red light source 42r and the blue-green light source 42bg to emit light and independently adjusting the light. Similarly, when the point indicating the chromaticity value desired by the user input to the input device 20 is located within the second region, the control unit 31 of the control device 30 does not cause the green light source 42g to emit light, and the blue light source 42b , a red light source 42r, and a bluish-green light source 42bg are caused to emit light and are independently dimmed, thereby realizing output light having a chromaticity value desired by the user.

Hereinafter, the general color rendering index Ra of the output light obtained by such a chromaticity control method will be described while comparing it with the general color rendering index Ra of the output light obtained by the chromaticity control method according to the comparative example. FIG. 3 is a diagram showing the general color rendering index Ra of the output light obtained by the chromaticity control method (hereinafter also simply referred to as control example 1) in the illumination system 10. As shown in FIG.

FIG. 3 also shows the general color rendering index Ra of the output light obtained by the chromaticity control method according to the comparative example. In the chromaticity control method according to the comparative example, the blue light source 42b, the green light source 42g, and the blue light source 42b, the green light source 42g, and the output light having the chromaticity values positioned within the point B1, the point G, and the point R are emitted without emitting the blue-green light source 42bg. And, it is a control method realized by making the three light sources of the red light source 42r emit light and adjusting the light independently. In other words, the comparative example differs from the control example 1 in the method of dividing a quadrangle into two triangular regions. In FIG. 3, the output light is white light with Duv=0. In FIG. 3, the horizontal axis indicates the color temperature (Tc) of the output light, and the vertical axis indicates the general color rendering index Ra of the output light.

As shown in FIG. 3, according to Control Example 1, output light having a higher general color rendering index Ra than the comparative example can be realized.

As described above, in the illumination system 10, the control unit 31 outputs light having chromaticity values within the first region with points G, R, and B2 as vertices, , and three light sources corresponding to points B2, and output light having chromaticity values within a second area of a triangle with points B1, R, and B2 as vertices It is realized by emitting light from three light sources corresponding to B1, point R, and point B2. Specifically, the first region is a triangular region whose vertices are the three points closest to the black body locus among points B1, G, R, and B2. is a triangular area obtained by excluding the first area from a quadrangular area having points B1, G, R, and B2 as vertices. This allows the illumination system 10 to achieve output light with a high general color rendering index Ra. The lighting system 10 can improve the general color rendering index Ra of output light having, for example, a light source color (one of five types) defined in JISZ9112, and reduce color unevenness on the light irradiation surface.

[Control example 2]
Chromaticity control example 2 of the illumination system 10 will be described with reference to a chromaticity diagram (chromaticity coordinates). FIG. 4 is a diagram showing chromaticity coordinates in which points related to control example 2 are plotted. The chromaticity coordinates in FIG. 4 indicate the color space defined in CIE1931. The chromaticity coordinates of FIG. 4 are basically the same as those of FIG. The difference is that P5 is shown.

The first point P1 is located on a line segment connecting a point B2 indicating the chromaticity value of the blue-green light source 42bg and a point G indicating the chromaticity value (an example of the first chromaticity value) of the green light source 42g. It is a point to do. A first point P1 is a point indicating a chromaticity value when each of the blue-green light source 42bg and the green light source 42g is caused to emit light with maximum brightness.

The second point P2 is located on a line segment connecting a point B2 indicating the chromaticity value of the blue-green light source 42bg and a point R indicating the chromaticity value (an example of the second chromaticity value) of the red light source 42r. It is a point to do. The second point P2 is a point indicating the chromaticity value when each of the blue-green light source 42bg and the red light source 42r is caused to emit light with maximum brightness.

The third point P3 is a point located within the first region. The third point P3 is the color when each of the three light sources (the green light source 42g, the red light source 42r, and the blue-green light source 42bg) corresponding to the three vertices of the first region emits light with maximum brightness. It is a point indicating a degree value.

A fourth point P4 is located on a line segment connecting a point B2 indicating the chromaticity value of the blue-green light source 42bg and a point B1 indicating the chromaticity value (an example of the third chromaticity value) of the blue light source 42b. It is a point to do. A fourth point P4 indicates a chromaticity value when each of the blue-green light source 42bg and the blue light source 42b is caused to emit light with maximum brightness.

A fifth point P5 is a point located within the second region. The fifth point P5 is the color when each of the three light sources (the blue light source 42b, the red light source 42r, and the blue-green light source 42bg) corresponding to the three vertices of the second region emits light with maximum brightness. It is a point indicating a degree value.

In the control example 1 described above, the chromaticity values in the first area of the triangle with the points G, R, and B2 as vertices cause the green light source 42g, the red light source 42r, and the blue-green light source 42bg to emit light. realized by Here, for the chromaticity values in the first target area (the hatched area in FIG. 4) in the first area, all of the blue light source 42b, the green light source 42g, the red light source 42r, and the blue-green light source 42bg are This can be realized by emitting light, and by doing so, it is possible to achieve both an improvement in the general color rendering index Ra of the output light and an increase in the amount of the output light.

Therefore, in Control Example 2, the control unit 31 causes all of the blue light source 42b, the green light source 42g, the red light source 42r, and the blue-green light source 42bg to emit light, and independently This is achieved by adjusting the Note that the first target area includes a rectangular area surrounded by a point B2 indicating the chromaticity value of the blue-green light source 42bg, a first point P1, a second point P2, and a third point P3, and a point G (first A point indicating a chromaticity value of 1), a point R (a point indicating a second chromaticity value), and a point B1 (an area overlapping a triangular area surrounded by points indicating a third chromaticity value). be.

For example, the control unit 31 realizes output light having a certain chromaticity value within the first target area as follows. The control unit 31 controls the chromaticity values in the first target area by causing the green light source 42g, the red light source 42r, and the blue-green light source 42bg to emit light without causing the blue light source 42b to emit light. to calculate the first dimming value. In addition, the second tone of each light source when realizing the above chromaticity value in the first target region by causing the blue light source 42b, the green light source 42g, and the red light source 42r to emit light without causing the blue-green light source 42bg to emit light. Calculate the light value. The control unit 31 sets the total light control value of the first light control value and the second light control value as the final light control value. FIG. 5 is a diagram showing simulation results of the luminous flux of output light and the general color rendering index Ra realized by Control Example 2. In FIG.

Control the output light having chromaticity values of x=0.263 and y=0.284 in the first target area, as shown in "Control Example 1" in the "First Target Area" column of FIG. When realized by Example 1, the total luminous flux is 125 and the general color rendering index Ra is 91. Note that realizing the output light according to Control Example 1 corresponds to causing the green light source 42g, the red light source 42r, and the blue-green light source 42bg to emit light at the first dimming value in the above description.

The "additional portion" in the "first target area" column in FIG. 5 indicates that the blue light source 42b, the green light source 42g, and the red light source 42r are caused to emit light at the second dimming value in the above description to realize the output light. It means the hypothetical case. In this case, the total luminous flux is 72 and the general color rendering index Ra is 84.

Control the output light having chromaticity values of x=0.263 and y=0.284 in the first target area, as shown in "Control Example 2" in the "First Target Area" column of FIG. When implemented in Example 2, the total luminous flux is 197 and the general color rendering index Ra is 93. In addition, realizing the output light by the control example 2 means that the final light control value obtained by summing the first light control value and the second light control value in the above description is the blue light source 42b, the green light source 42g, the red light source 42r, and the light source 42r. And it corresponds to making the blue-green light source 42bg emit light.

In this way, according to Control Example 2, it is possible to achieve both an improvement in the general color rendering index Ra and an increase in the light amount of the output light having the chromaticity value within the first target region. In Control Example 2, when output light having the above chromaticity value within the first target area is emitted from the illumination device 40, the blue-green light source 42bg emits light with maximum output (maximum brightness).

Further, in the control example 1 described above, the chromaticity values in the second area of the triangle with the points B1, R, and B2 as vertices are the blue light source 42b, the red light source 42r, and the blue-green light source 42bg. realized by luminescence. Here, for the chromaticity values within the second target region (the hatched region in FIG. 4) within the second region, all of the blue light source 42b, the green light source 42g, the red light source 42r, and the blue-green light source 42bg are This can be realized by emitting light, and by doing so, it is possible to achieve both an improvement in the general color rendering index Ra of the output light and an increase in the amount of the output light.

Therefore, in Control Example 2, the control unit 31 causes all of the blue light source 42b, the green light source 42g, the red light source 42r, and the blue-green light source 42bg to emit light, and independently This is achieved by adjusting the The second target area includes a rectangular area surrounded by a point B2, a second point P2, a fourth point P4, and a fifth point P5 indicating the chromaticity value of the bluish-green light source 42bg, and a point G (the second target area). 1 point), point R (second chromaticity value), and point B1 (third chromaticity value). is.

For example, the control unit 31 realizes output light having a certain chromaticity value within the second target area as follows. The control unit 31 controls the chromaticity values in the second target region by causing the blue light source 42b, the red light source 42r, and the blue-green light source 42bg to emit light without causing the green light source 42g to emit light. to calculate the third dimming value. Further, the fourth tone of each light source when realizing the above chromaticity value in the second target region by causing the blue light source 42b, the green light source 42g, and the red light source 42r to emit light without causing the blue-green light source 42bg to emit light. Calculate the light value. The control unit 31 sets the total light control value of the third light control value and the fourth light control value as the final light control value.

As shown in "Control Example 1" in the "Second Target Area" column of FIG. When realized by control example 1, the total luminous flux is 115 and the general color rendering index Ra is 92. Note that realizing the output light according to Control Example 1 corresponds to causing the blue light source 42b, the red light source 42r, and the blue-green light source 42bg to emit light at the third dimming value in the above description.

The "addition" in the column "second target area" in FIG. 5 indicates that the blue light source 42b, the green light source 42g, and the red light source 42r are caused to emit light at the fourth dimming value in the above description to realize the output light. It means the hypothetical case. In this case, the total luminous flux is 91 and the general color rendering index Ra is 82.

Control the output light having chromaticity values of x=0.254 and y=0.270 in the second target area, as shown in "Control Example 2" in the "Second Target Area" column of FIG. When implemented in Example 2, the total luminous flux is 206 and the general color rendering index Ra is 92. It should be noted that realizing the output light by the control example 2 means that the final light control value obtained by summing the third light control value and the fourth light control value in the above description is the blue light source 42b, the green light source 42g, the red light source 42r, And it corresponds to making the blue-green light source 42bg emit light.

As described above, according to Control Example 2, it is possible to achieve both an improvement in the general color rendering index Ra and an increase in the light amount of the output light having the chromaticity value within the second target region. In Control Example 2, when output light having the above chromaticity value within the second target region is emitted from the illumination device 40, the blue-green light source 42bg emits light with maximum output (maximum brightness).

In addition, in the first target region and the second target region, application of control example 1 or application of control example 2 may be switched. For example, the control unit 31 operates in a color rendering emphasis mode that emphasizes the color rendering of output light having chromaticity values belonging to the first target area and the second target area, and An operation in a light amount emphasizing mode that emphasizes the light amount of output light having a chromaticity value may be selectively executed. In the operation of the color-rendering-emphasized mode, as described in Control Example 1, the control unit 31 causes the three light sources corresponding to the three vertices of the first region to emit light for the chromaticity values belonging to the first target region. and the chromaticity values belonging to the second region of interest are realized by emitting three light sources corresponding to the three vertices of the second region. In the operation of the light amount emphasizing mode, as described in Control Example 2, the control unit 31 controls the chromaticity values belonging to the first target region and the second target region by causing the four light sources included in the lighting system 10 to emit light. come true. The color-rendering-oriented mode is an example of the first mode, and the light-quantity-oriented mode is an example of the second mode. Such switching of operation modes is performed based on user input to the input device 20, for example.

(Embodiment 2)
[Constitution]
First, the configuration of the lighting system according to Embodiment 2 will be described. FIG. 6 is a block diagram showing a functional configuration of a lighting system according to Embodiment 2. FIG.

The illumination system 10a according to Embodiment 2 independently adjusts the blue light source 42b, the green light source 42g, the red light source 42r, and the yellow light source 42y included in the light source unit 42a included in the illumination device 40a. This is a system capable of causing the illumination device 40a to emit light with a user's desired chromaticity. That is, the lighting system 10a is a system that supports the chromaticity adjustment function of the lighting device 40a. The lighting system 10a includes an input device 20, a control device 30, and a lighting device 40a. Note that the lighting system 10 a may include a plurality of lighting devices 40 a for one control device 30 .

Since the input device 20 and the control device 30 have already been described, detailed description thereof will be omitted.

The illumination device 40a has substantially the same configuration as the illumination device 40, but differs in that it includes a yellow light source 42y instead of the blue-green light source 42bg.

The yellow light source 42y is a light source that emits yellow light, and is an example of another light source. The yellow light source 42y emits yellow light with an emission peak wavelength of 550 nm or more and 590 nm or less, for example. The yellow light source 42y is specifically a light-emitting module using an LED that emits yellow light, but the specific aspect of the yellow light source 42y is not particularly limited.

The basic configurations of the blue light source 42b, the green light source 42g, and the red light source 42r included in the illumination device 40a are the same as those of the blue light source 42b, the green light source 42g, and the red light source 42r included in the illumination device 40. However, the chromaticity values are slightly different.

[Chromaticity control example 1]
When controlling the chromaticity of the output light of the lighting device 40a, the illumination system 10a selectively causes the blue light source 42b, the green light source 42g, the red light source 42r, and the yellow light source 42y to emit light, thereby rendering the output light chromaticity. can improve sexuality. The output light is light obtained by synthesizing at least one of the light emitted by the red light source 42r, the light emitted by the green light source 42g, the light emitted by the blue light source 42b, and the light emitted by the yellow light source 42y. means the light finally emitted from the A chromaticity control example 1 of the lighting system 10a will be described below with reference to a chromaticity diagram (chromaticity coordinates). FIG. 7 is a diagram showing chromaticity coordinates in which chromaticity values of the red light source 42r, the green light source 42g, the blue light source 42b, and the yellow light source 42y are plotted. The chromaticity coordinates in FIG. 7 indicate the color space defined in CIE1931.

In the chromaticity coordinates of FIG. 7, a point B indicating the chromaticity value of the blue light emitted by the blue light source 42b, a point G indicating the chromaticity value of the green light emitted by the green light source 42g, and the color of the red light emitted by the red light source 42r. A point R indicating the chromaticity value and a point Y indicating the fourth chromaticity value of the blue-green light emitted by the yellow light source 42y are shown.

On the chromaticity coordinates, a quadrangular area having points B, G, R, and Y as vertices includes the chromaticity range of the light source color defined by JISZ9112. Here, the light source color means five types of daylight color (D), daylight white (N), white (W), warm white (WW), and light bulb color (L). The degree ranges are the five roughly parallelogram regions near the blackbody locus in FIG. The illumination system 10a can realize output light having chromaticity values within a rectangular region with points B, G, R, and Y as vertices. can be said to have a relatively wide chromaticity range.

The illumination system 10a is configured such that the quadrangular region is a first triangular region having points B, R, and Y as vertices, and a second triangular region having points B, G, and Y as vertices. The color rendering of the output light can be improved by adjusting the chromaticity by dividing it into regions. When dividing a quadrangular region into two triangular regions, there are two ways of dividing. A triangular area whose vertices are the top three points closest to the body trajectory is defined as the first area, and a triangular area obtained by excluding the first area from the quadrilateral area is defined as the second area. Note that the distance from the point B to the blackbody locus means, for example, the average value of the distances from the point B to each of a plurality of points when the blackbody locus is regarded as a set of a plurality of points. The same applies to the distances from points G, R, and Y to the black body locus.

For example, when the point indicating the chromaticity value desired by the user input to the input device 20 is located within the first region, the control unit 31 of the control device 30 does not cause the green light source 42g to emit light, and the blue light source 42b, Output light having a chromaticity value desired by the user is realized by causing the three light sources of the red light source 42r and the yellow light source 42y to emit light and adjusting the light independently. Similarly, when the point indicating the chromaticity value desired by the user input to the input device 20 is located within the second region, the control unit 31 of the control device 30 does not cause the red light source 42r to emit light, and causes the blue light source 42b to emit light. , a green light source 42g, and a yellow light source 42y, and by independently dimming the three light sources, output light having a chromaticity value desired by the user is realized.

Hereinafter, the general color rendering index Ra of the output light obtained by such a chromaticity control method will be described while comparing it with the general color rendering index Ra of the output light obtained by the chromaticity control method according to the comparative example. FIG. 8 is a diagram showing the general color rendering index Ra of the output light obtained by the chromaticity control method (hereinafter also simply referred to as control example 1) in the illumination system 10a.

FIG. 8 also shows the general color rendering index Ra of the output light obtained by the chromaticity control method according to the comparative example. In the chromaticity control method according to the comparative example, output light having chromaticity values positioned within points B, G, and R is emitted from the blue light source 42b, the green light source 42g, and the yellow light source 42y without emitting the yellow light source 42y. , and the red light source 42r, and control the light independently. In other words, the comparative example differs from the control example 1 in the method of dividing a quadrangle into two triangular regions. In FIG. 8, the output light is white light with Duv=0. In FIG. 8, the horizontal axis indicates the color temperature (Tc) of the output light, and the vertical axis indicates the general color rendering index Ra of the output light.

As shown in FIG. 8, according to Control Example 1, output light having a higher general color rendering index Ra than the comparative example can be realized.

As described above, in the illumination system 10a, the control unit 31 outputs light having chromaticity values within the first region with points B, R, and Y as vertices, , and three light sources corresponding to points Y, and the output light having chromaticity values within a second region of a triangle having points B, G, and Y as vertices is defined as a point This is realized by emitting light from three light sources corresponding to B, point G, and point Y. FIG. Specifically, the first area is a triangular area whose vertices are the three points closest to the blackbody locus among points B, G, R, and Y. The second area is is a triangular area obtained by excluding the first area from a quadrangular area having points B, G, R, and Y as vertices. Thereby, the illumination system 10a can realize output light having a high general color rendering index Ra. The lighting system 10a can, for example, improve the general color rendering index Ra of output light having a light source color (one of five types) defined in JISZ9112, and reduce color unevenness on the light irradiation surface.

[Control example 2]
Chromaticity control example 2 of the lighting system 10a will be described with reference to a chromaticity diagram (chromaticity coordinates). FIG. 9 is a diagram showing chromaticity coordinates in which points related to Control Example 2 are plotted. The chromaticity coordinates in FIG. 9 indicate the color space defined in CIE1931. The chromaticity coordinates of FIG. 9 are basically the same as those of FIG. The difference is that P5 is shown.

The first point P1 is on a line segment connecting a point Y indicating the chromaticity value of the yellow light source 42y and a point R indicating the chromaticity value (another example of the first chromaticity value) of the red light source 42r. It is the point where it is located. A first point P1 is a point indicating a chromaticity value when each of the yellow light source 42y and the red light source 42r is caused to emit light with maximum brightness.

The second point P2 is on a line segment connecting a point Y indicating the chromaticity value of the yellow light source 42y and a point B indicating the chromaticity value (another example of the second chromaticity value) of the blue light source 42b. It is the point where it is located. A second point P2 is a point indicating the chromaticity value when each of the yellow light source 42y and the blue light source 42b is caused to emit light with maximum brightness.

The third point P3 is a point located within the first region. The third point P3 is the chromaticity when each of the three light sources (blue light source 42b, red light source 42r, and yellow light source 42y) corresponding to the three vertices of the first region emits light with maximum brightness. It is the point that shows the value.

A fourth point P4 is on a line segment connecting a point Y indicating the chromaticity value of the yellow light source 42y and a point G indicating the chromaticity value (another example of the third chromaticity value) of the green light source 42g. It is the point where it is located. A fourth point P4 indicates a chromaticity value when each of the yellow light source 42y and the green light source 42g emits light with maximum brightness.

A fifth point P5 is a point located within the second region. The fifth point P5 is the chromaticity when each of the three light sources (the blue light source 42b, the green light source 42g, and the yellow light source 42y) corresponding to the three vertices of the second region emits light with maximum brightness. It is the point that shows the value.

In the control example 1 described above, the chromaticity values in the first area of the triangle with the points B, R, and Y as vertices are such that the blue light source 42b, the red light source 42r, and the yellow light source 42y emit light. Realized by Here, for the chromaticity values within the first target region (the hatched region in FIG. 9) within the first region, all of the blue light source 42b, green light source 42g, red light source 42r, and yellow light source 42y are emitted. By doing so, it is possible to achieve both an improvement in the general color rendering index Ra of the output light and an increase in the amount of the output light.

Therefore, in Control Example 2, the control unit 31 causes all of the blue light source 42b, the green light source 42g, the red light source 42r, and the yellow light source 42y to emit light, and independently This is achieved by dimming the Note that the first target area includes a rectangular area surrounded by a point Y indicating the chromaticity value of the yellow light source 42y, a first point P1, a second point P2, and a third point P3, and a point R (first point indicating the chromaticity value), point B (point indicating the second chromaticity value), and point G (point indicating the third chromaticity value). be.

For example, the control unit 31 realizes output light having a certain chromaticity value within the first target area as follows. The control unit 31 controls the chromaticity values in the first target area by causing the blue light source 42b, the red light source 42r, and the yellow light source 42y to emit light without causing the green light source 42g to emit light. A fifth dimming value is calculated. A sixth dimming of each light source when the chromaticity value in the first target area is achieved by causing the blue light source 42b, the green light source 42g, and the red light source 42r to emit light without causing the yellow light source 42y to emit light. Calculate the value. The control unit 31 sets the total light control value of the fifth light control value and the sixth light control value as the final light control value, so that the output light having the above chromaticity value in the first target area, It is possible to achieve both an improvement in the general color rendering index Ra and an increase in the amount of light. In Control Example 2, when output light having the above chromaticity value within the first target region is emitted from the illumination device 40a, the yellow light source 42y emits light with maximum output (maximum brightness).

In the control example 1 described above, the chromaticity values in the second region of the triangle with the points B, G, and Y as vertices are the blue light source 42b, the green light source 42g, and the yellow light source 42y. realized by letting Here, for the chromaticity values within the second target region (the hatched region in FIG. 9) within the second region, all of the blue light source 42b, green light source 42g, red light source 42r, and yellow light source 42y are emitted. By doing so, it is possible to achieve both an improvement in the general color rendering index Ra of the output light and an increase in the amount of the output light.

Therefore, in Control Example 2, the control unit 31 causes all of the blue light source 42b, the green light source 42g, the red light source 42r, and the yellow light source 42y to emit light, and independently This is achieved by dimming the The second target area is a rectangular area surrounded by a point Y indicating the chromaticity value of the yellow light source 42y, a second point P2, a fourth point P4, and a fifth point P5, and a point R (first point indicating the chromaticity value), point B (point indicating the second chromaticity value), and point G (point indicating the third chromaticity value). be.

For example, the control unit 31 realizes output light having a certain chromaticity value within the second target area as follows. The control unit 31 controls the chromaticity values in the second target region by causing the blue light source 42b, the green light source 42g, and the yellow light source 42y to emit light without causing the red light source 42r to emit light. A seventh dimming value is calculated. Further, the eighth dimming of each light source when the above chromaticity value in the second target region is achieved by causing the blue light source 42b, the green light source 42g, and the red light source 42r to emit light without causing the yellow light source 42y to emit light. Calculate the value. The control unit 31 sets the total light control value of the seventh light control value and the eighth light control value as the final light control value, so that the output light having the chromaticity value in the second target area is It is possible to achieve both an improvement in the general color rendering index Ra and an increase in the amount of light. In Control Example 2, when output light having the above chromaticity value within the second target region is emitted from the illumination device 40a, the yellow light source 42y emits light with maximum output (maximum brightness).

In addition, in the first target region and the second target region, application of control example 1 or application of control example 2 may be switched. For example, the control unit 31 operates in a color rendering emphasis mode that emphasizes the color rendering of output light having chromaticity values belonging to the first target area and the second target area, and An operation in a light amount emphasizing mode that emphasizes the light amount of output light having a chromaticity value may be selectively executed. In the operation of the color-rendering-emphasized mode, as described in Control Example 1, the control unit 31 causes the three light sources corresponding to the three vertices of the first region to emit light for the chromaticity values belonging to the first target region. and the chromaticity values belonging to the second region of interest are realized by emitting three light sources corresponding to the three vertices of the second region. In the operation of the light amount emphasizing mode, as described in Control Example 2, the control unit 31 controls the chromaticity values belonging to the first target region and the second target region by causing the four light sources included in the lighting system 10a to emit light. come true. The color-rendering-oriented mode is an example of the first mode, and the light-quantity-oriented mode is an example of the second mode. Such switching of operation modes is performed based on user input to the input device 20, for example.

(Modification)
In the first and second embodiments, the blue light emitted by the blue light source 42b, the green light emitted by the green light source 42g, the red light emitted by the red light source 42r, the blue-green light emitted by the blue-green light source 42bg, and the yellow light source 42y are emitted. Yellow light was realized by the emitted light of the LED. Here, the green light emitted by the green light source 42g, the red light emitted by the red light source 42r, and the yellow light emitted by the yellow light source 42y may be realized by fluorescence emitted by phosphors.

In this case, each of the green light source 42g, the red light source 42r, and the yellow light source 42y includes, for example, an excitation light source realized by a blue LED or the like, and a phosphor-containing resin that seals the excitation light source. The phosphor constituting the green _{light source 42g is an yttrium-aluminum-garnet (YAG)-based green phosphor such as Y3(Al, Ga)5O12 : Ce phosphor ,} but _Lu3Al5O12 : It may also be a lutetium-aluminum-garnet (LuAG)-based green phosphor, such as a Ce phosphor. The phosphor constituting the red light source 42r is a red phosphor such as CaAlSiN ₃ :Eu phosphor or (Sr,Ca)AlSiN ₃ :Eu phosphor. The phosphor constituting _{the yellow light source 42y is an yttrium-aluminum-garnet (YAG)-based yellow phosphor such as a Y3(Al, Ga)5O12 : Ce phosphor ,} but _Lu3Al5O12 : It may also be a lutetium-aluminum-garnet (LuAG)-based yellow phosphor, such as a Ce phosphor.

According to Control Example 1 of Embodiments 1 and 2, each of the green light emitted by the green light source 42g, the red light emitted by the red light source 42r, and the yellow light emitted by the yellow light source 42y is generated by the fluorescence emitted by the phosphor. Even when it is realized, it is possible to improve the general color rendering index Ra of the output light.

(effects, etc.)
As described above, the illumination system 10 or the illumination system 10a includes the controller 31 that controls four light sources that emit light with different chromaticity values. On the chromaticity coordinates, a quadrangular area whose vertices are four points corresponding to the chromaticity values of the light emitted by the four light sources includes at least part of the chromaticity range of the light source colors defined in JISZ9112. The control unit 31 outputs light having chromaticity values within a first area of a triangle whose vertices are the top three points of the four points that are closest to the blackbody locus. is realized by emitting light from three light sources corresponding to the three vertices of the four light sources, and output light having chromaticity values within a second triangular region obtained by excluding the first region from the quadrangular region is selected from the four light sources. This is achieved by emitting light from three light sources corresponding to the three vertices of the two regions.

Such an illumination system 10 or illumination system 10a can achieve output light with a high general color rendering index Ra.

Also for example, the four light sources include red light source 42r, green light source 42g, blue light source 42b, and other light sources. Points indicating chromaticity values of other light sources are included in all of the three vertices of the first area and the three vertices of the second area.

Such illumination system 10 or illumination system 10a can realize output light having a high general color rendering index Ra by controlling the red light source 42r, the green light source 42g, the blue light source 42b, and other light sources. can.

Also, in the illumination system 10, the other light source is another blue light source (blue-green light source 42bg). The three vertices of the first region include a point indicating the chromaticity value of the blue-green light source 42bg, a point indicating the chromaticity value of the red light source 42r, and a point indicating the chromaticity value of the green light source 42g. The three vertices of the second area include a point indicating the chromaticity value of the blue-green light source 42bg, a point indicating the chromaticity value of the red light source 42r, and a point indicating the chromaticity value of the blue light source 42b.

Such a lighting system 10 can achieve output light with a high general color rendering index Ra.

Also, in the illumination system 10a, the other light source is the yellow light source 42y. The three vertices of the first region include a point indicating the chromaticity value of the yellow light source 42y, a point indicating the chromaticity value of the blue light source 42b, and a point indicating the chromaticity value of the red light source 42r. The three vertices of the second area include a point indicating the chromaticity value of the yellow light source 42y, a point indicating the chromaticity value of the blue light source 42b, and a point indicating the chromaticity value of the green light source 42g.

Such an illumination system 10a can achieve output light with a high general color rendering index Ra.

Also, for example, the three vertices of the first region include a point indicating the chromaticity value of another light source, a point indicating the first chromaticity value, and a point indicating the second chromaticity value. On the line segment connecting the point indicating the chromaticity value of the other light source and the point indicating the first chromaticity value, the light source corresponding to the point indicating the other light source and the first chromaticity value is shown. A first point P1 is included which indicates the chromaticity value when each is illuminated with maximum brightness. On the line segment connecting the point indicating the chromaticity value of the other light source and the point indicating the second chromaticity value, the light source corresponding to the point indicating the other light source and the second chromaticity value is shown. A second point P2 is included which indicates the chromaticity value when each is illuminated at maximum brightness. The first area includes a third point P3 indicating the chromaticity value when each of the three light sources corresponding to the three vertices of the first area emits light with maximum brightness. The three vertices of the second region include a point indicating the chromaticity value of the other light source, a point indicating the second chromaticity value, and a point indicating the third chromaticity value. On the line segment connecting the point indicating the chromaticity value of the other light source and the point indicating the third chromaticity value, the light source corresponding to the point indicating the other light source and the third chromaticity value A fourth point P4 indicating the chromaticity value when each of the light sources emits light at maximum brightness is included, and the second region contains the three light sources corresponding to the three vertices of the second region, each of which has the maximum brightness. A fifth point P5 is included which indicates the chromaticity value when light is emitted with a brightness of . The control unit 31 causes the four light sources to emit the output light having the chromaticity value located within the first target region and the output light having the chromaticity value located within the second target region. come true. The first target area indicates the first chromaticity value and the area surrounded by the points indicating the chromaticity values of the other light sources, the first point P1, the second point P2, and the third point P3. The area surrounded by the point, the point indicating the second chromaticity value, and the point indicating the third chromaticity value overlaps. The second target area indicates the first chromaticity value and the area surrounded by the points indicating the chromaticity values of the other light sources, the second point P2, the fourth point P4, and the fifth point P5. The area surrounded by the point, the point indicating the second chromaticity value, and the point indicating the third chromaticity value overlaps.

Such an illumination system 10 or illumination system 10a can increase the maximum amount of output light having chromaticity values within the first target area and the second target area.

Further, for example, the control unit 31 realizes output light having a chromaticity value within the first target region by causing three light sources corresponding to the three vertices of the first region to emit light, and A first mode of control realized by emitting output light having chromaticity values within the region by emitting three light sources corresponding to the three vertices of the second region, and within the first target region and the second target A second mode of control is selectively executed in which output light having a chromaticity value within the region is realized by causing four light sources to emit light. The first mode is, for example, the color-rendering-oriented mode of the above-described embodiment, and the second mode is, for example, the light-quantity-oriented mode of the above-described embodiment.

Such an illumination system 10 or illumination system 10a can switch the implementation method (chromaticity control method) of the chromaticity values in the first target region and the second target region.

In addition, the lighting method executed by a computer such as the lighting system 10 or the lighting system 10a includes a control step of controlling four light sources that emit light with different chromaticity values, and the four light sources on the chromaticity coordinates are A quadrangular area whose vertices are four points corresponding to the chromaticity values of the emitted light includes at least part of the chromaticity range of the light source color defined in JISZ9112. In the control step, output light having a chromaticity value within a first region of a triangle whose vertices are the top three points of the four points that are closest to the blackbody locus is converted to the first region of the four light sources. is realized by emitting light from three light sources corresponding to the three vertices of the four light sources, and output light having chromaticity values within a second triangular region obtained by excluding the first region from the quadrangular region is selected from the four light sources. This is achieved by emitting light from three light sources corresponding to the three vertices of the two regions.

Such an illumination method can achieve output light with a high general color rendering index Ra.

(Other embodiments)
Although the embodiments have been described above, the present invention is not limited to the above embodiments.

For example, it is not essential that a blue light source, a green light source, and a red light source are used as the three light sources other than the other light sources. As the three light sources, it is sufficient to use three light sources having chromaticity values that form a triangle that includes at least part of the chromaticity range of the light source color on the chromaticity coordinates. Also, other light sources are not limited to blue-green light sources or yellow light sources.

In the above embodiments, the light emitted by the light source is realized by the emitted light of the LED or the fluorescent light emitted by the phosphor. It may be realized by emitted light, emitted light from an inorganic EL element, or the like.

For example, although the lighting system was realized by a plurality of devices in the above embodiments, it may be realized as a single device. For example, the lighting system may be realized as a single device corresponding to the control device according to the above embodiments. When the lighting system is implemented by multiple devices, the components included in the lighting system described in the above embodiments may be distributed to the multiple devices in any way.

Further, in the above-described embodiments, the processing executed by a specific processing unit may be executed by another processing unit. In addition, the order of multiple processes may be changed, and multiple processes may be executed in parallel.

Also, in the above embodiments, each component may be realized by executing a software program suitable for each component. Each component may be realized by reading and executing a software program recorded in a recording medium such as a hard disk or a semiconductor memory by a program execution unit such as a CPU or processor.

Also, each component may be realized by hardware. Each component may be a circuit (or integrated circuit). These circuits may form one circuit as a whole, or may be separate circuits. These circuits may be general-purpose circuits or dedicated circuits.

Also, general or specific aspects of the present invention may be implemented in a system, apparatus, method, integrated circuit, computer program or recording medium such as a computer-readable CD-ROM. Also, any combination of systems, devices, methods, integrated circuits, computer programs and recording media may be implemented.

For example, the present invention may be implemented as a lighting method executed by a computer such as a lighting system, or may be implemented as a program for causing a computer to execute the lighting method, or such a program may be recorded. It may also be implemented as a non-transitory computer-readable recording medium.

In addition, forms obtained by applying various modifications to each embodiment that a person skilled in the art can think of, or realized by arbitrarily combining the constituent elements and functions of each embodiment without departing from the spirit of the present invention. Also included in the present invention.

10, 10a lighting system 20 input device 30 control device 31 control section 32 storage section 40, 40a lighting device 41 dimming circuit 42, 42a light source section 42b blue light source 42bg blue-green light source 42g green light source 42r red light source 42y yellow light source

Claims (8)

A control unit that controls four light sources that emit light with different chromaticity values,
On the chromaticity coordinates, a quadrangular region whose vertices are four points corresponding to the chromaticity values of the light emitted by the four light sources includes at least part of the chromaticity range of the light source color defined in JISZ9112. ,
The control unit
Output light having a chromaticity value within a first region of a triangle having vertices of the top three points closest to the blackbody locus among the four points is selected from three of the four light sources in the first region. Realized by emitting light from three light sources corresponding to three vertices,
Output light having a chromaticity value within a second triangular region obtained by excluding the first region from the quadrangular region is emitted from three light sources among the four light sources corresponding to three vertices of the second region. A lighting system realized by the four light sources include a red light source, a green light source, a blue light source, and other light sources;
The lighting system according to claim 1, wherein the points indicating the chromaticity values of the other light sources are included in all of the three vertices of the first area and the three vertices of the second area. The other light source is another blue light source,
The three vertices of the first region include a point indicating the chromaticity value of the other blue light source, a point indicating the chromaticity value of the red light source, and a point indicating the chromaticity value of the green light source. be,
The three vertices of the second region include a point indicating the chromaticity value of the other blue light source, a point indicating the chromaticity value of the red light source, and a point indicating the chromaticity value of the blue light source. 3. The lighting system of claim 2. the other light source is a yellow light source,
The three vertices of the first region include a point indicating the chromaticity value of the yellow light source, a point indicating the chromaticity value of the blue light source, and a point indicating the chromaticity value of the red light source,
The three vertices of the second region include a point indicating the chromaticity value of the yellow light source, a point indicating the chromaticity value of the blue light source, and a point indicating the chromaticity value of the green light source. 3. The lighting system according to 2. The three vertices of the first region include a point indicating the chromaticity value of the other light source, a point indicating the first chromaticity value, and a point indicating the second chromaticity value,
On a line segment connecting the point indicating the chromaticity value of the other light source and the point indicating the first chromaticity value, the point indicating the other light source and the first chromaticity value including a first point representing a chromaticity value when each of the corresponding light sources is illuminated at maximum brightness;
On a line segment connecting the point indicating the chromaticity value of the other light source and the point indicating the second chromaticity value, the point indicating the other light source and the second chromaticity value including a second point indicating the chromaticity value when each of the corresponding light sources is illuminated at maximum brightness;
The first region includes a third point indicating a chromaticity value when each of the three light sources corresponding to the three vertices of the first region emits light with maximum brightness,
The three vertices of the second region include a point indicating the chromaticity value of the other light source, a point indicating the second chromaticity value, and a point indicating the third chromaticity value,
On a line segment connecting the point indicating the chromaticity value of the other light source and the point indicating the third chromaticity value, the point indicating the other light source and the third chromaticity value including a fourth point indicating the chromaticity value when each of the corresponding light sources is illuminated at maximum brightness;
The second area includes a fifth point indicating the chromaticity value when each of the three light sources corresponding to the three vertices of the second area emits light with maximum brightness,
The control unit causes the four light sources to emit output light having chromaticity values located within a first target region and output light having chromaticity values located within a second target region, respectively. realized with
The first target area includes a point indicating the chromaticity value of the other light source, an area surrounded by the first point, the second point, and the third point, and the first chromaticity. a region where a point indicating a value, a point indicating the second chromaticity value, and a region surrounded by points indicating the third chromaticity value overlap;
The second target area includes a point indicating the chromaticity value of the other light source, an area surrounded by the second point, the fourth point, and the fifth point, and the first chromaticity. 5. The area defined by the point indicating the second chromaticity value, the point indicating the second chromaticity value, and the point indicating the third chromaticity value overlap. The described lighting system. The control unit realizes output light having a chromaticity value within the first target area by emitting light from three light sources corresponding to three vertices of the first target area, and Control of a first mode realized by emitting three light sources corresponding to three vertices of the second region, and output light having a chromaticity value within the first target region and the second 6. The lighting system according to claim 5, wherein a second mode of control is selectively executed, wherein output light having a chromaticity value within a target region is realized by causing the four light sources to emit light. including a control step of controlling four light sources that emit light with different chromaticity values;
On the chromaticity coordinates, a quadrangular region whose vertices are four points corresponding to the chromaticity values of the light emitted by the four light sources includes at least part of the chromaticity range of the light source color defined in JISZ9112. ,
In the control step,
Output light having a chromaticity value within a first region of a triangle having vertices of the top three points closest to the blackbody locus among the four points is selected from three of the four light sources in the first region. Realized by emitting light from three light sources corresponding to three vertices,
Output light having a chromaticity value within a second triangular region obtained by excluding the first region from the quadrangular region is emitted from three light sources among the four light sources corresponding to three vertices of the second region. A lighting method realized by A program for causing a computer to execute the lighting method according to claim 7.

Images