Lighting device and luminaire

Abstract

To provide a lighting device capable of faithfully reproducing a color of an irradiated object.SOLUTION: The lighting system A1 is provided with two kinds of LED10, 20 and a lighting device 2. The two types of LED10 20, 20 include a first 1LED10 and a second 1LED10 that emits light having a higher color gamut area ratio than the first 2LED20. The lighting device 2 individually dims the 1LED10 and the 2LED20 so that the ratio of the light flux of the 1LED10 to the total light flux becomes large when the total light flux of the 1LED10 and the 2LED20 is larger than the thresholds. The lighting device 2 individually dims the first 2LED20 and the second 1LED10 so as to increase the ratio of the light flux of the first 2LED20 to the total light flux. The lighting device 2 individually dims the 1LED10 and the 2LED20 so that the ratio of the light flux of the 1LED10 and the ratio of the light flux of the 2LED20 are the same.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates generally to lighting devices and lighting fixtures, and more particularly to lighting devices including at least two types of LEDs and lighting fixtures including lighting devices. [Background technology]

[0002] The illumination device (lighting fixture) described in Patent Document 1 is exemplified. The illumination device described in Patent Document 1 includes a device main body, a light source device, and a lighting device. The light source device has a light source. The light source includes a plurality of white LEDs that emit white light and a plurality of RGB chips that emit white light.

[0003] The lighting device described in Patent Document 1 controls the color gamut area of ​​the illumination light by appropriately setting the luminous flux of a plurality of white LEDs and the luminous flux of a plurality of RGB chips. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-204659 Summary of the Invention [Problem to be solved by the invention]

[0005] In the lighting device described in Patent Document 1, the color gamut area of ​​the illumination light is controlled, thereby making it possible to make the color of an object (illuminated object) illuminated by the illumination light appear vivid.

[0006] However, with the lighting device described in Patent Document 1, for example, the color of the illuminated object may differ from the color of an object illuminated by natural light, making it difficult to faithfully reproduce the color of the illuminated object.

[0007] An object of the present disclosure is to provide a lighting device and a lighting fixture that can faithfully reproduce the color of an illuminated object. [Means for solving the problem]

[0008] An illumination device according to one aspect of the present disclosure includes at least two types of LEDs and a lighting device. The lighting device individually lights up the at least two types of LEDs. The at least two types of LEDs include a first LED and a second LED. The second LED emits light with a color gamut area ratio higher than that of the first LED. The lighting device is configured to individually dim the first LED and the second LED according to a total luminous flux of light that is a combination of light emitted from the first LED and light emitted from the second LED. When the total luminous flux is greater than a threshold, the lighting device individually dims the first LED and the second LED so that a proportion of the luminous flux of the first LED in the total luminous flux increases. When the total luminous flux is smaller than the threshold, the lighting device individually dims the first LED and the second LED so that a proportion of the luminous flux of the second LED in the total luminous flux increases. When the total luminous flux is equal to the threshold value, the lighting device individually dims the first LED and the second LED so that the proportion of the luminous flux of the first LED and the proportion of the luminous flux of the second LED are equal.

[0009] Another lighting device according to one aspect of the present disclosure includes at least two types of LEDs and a lighting device. The lighting device individually lights up the at least two types of LEDs. The at least two types of LEDs include a first LED and a second LED. The second LED emits light with a color gamut area ratio higher than that of the first LED. The lighting device is configured to individually dim the first LED and the second LED according to a total luminous flux of light that is a combination of light emitted from the first LED and the light emitted from the second LED. The lighting device individually dims the first LED and the second LED so that the proportion of the luminous flux of the first LED in the total luminous flux increases as the total luminous flux increases.

[0010] A lighting fixture according to one aspect of the present disclosure includes the lighting device and a fixture body that houses the lighting device. [Effects of the Invention]

[0011] According to one aspect of the present disclosure, it is possible to faithfully reproduce the color of an illuminated object. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a system configuration diagram of a lighting device according to an embodiment. [Figure 2] FIG. 2 is an explanatory diagram illustrating dimming of the first LED and the second LED in the lighting device. [Figure 3] FIG. 3 is another explanatory diagram illustrating dimming of the first LED and the second LED in the lighting device. [Figure 4] FIG. 4 is yet another explanatory diagram illustrating dimming of the first LED and the second LED in the lighting device. [Figure 5] FIG. 5 is another explanatory diagram illustrating dimming of the first LED and the second LED in the lighting device. [Figure 6] FIG. 6 is yet another explanatory diagram illustrating dimming of the first LED and the second LED in the lighting device. [Figure 7] FIG. 7 is a graph showing the CIE1964 uniform color space of the above lighting device. [Figure 8] FIG. 8 is a graph showing the CIE1964 uniform color space of the lighting device of Comparative Example 1. [Figure 9] FIG. 9 is a graph showing the CIE1964 uniform color space of the lighting device of Comparative Example 2. [Figure 10] FIG. 10 is a graph illustrating the conditional expressions of the above lighting device. [Figure 11] FIG. 11 is a perspective view of a lighting fixture including the lighting device. DETAILED DESCRIPTION OF THE INVENTION

[0013] A lighting fixture including a lighting device according to an embodiment will be described below with reference to the drawings. The figures described in the following embodiments are schematic diagrams, and the ratios of the sizes and thicknesses of the components do not necessarily reflect the actual dimensional ratios. Furthermore, the configurations described in the following embodiments are merely examples of the present disclosure. The present disclosure is not limited to the following embodiments, and various modifications are possible depending on the design, etc., as long as the effects of the present disclosure can be achieved.

[0014] (Embodiment) An illumination device A1 according to an embodiment will be described below with reference to FIGS.

[0015] (1) Lighting equipment 1 is an illumination device that illuminates, for example, an artwork in an art gallery or museum. The illumination device A1 includes, for example, a plurality of first LEDs 10, a plurality of second LEDs 20, and a lighting device 2. In other words, the illumination device A1 includes two types of LEDs 10 and 20, and a lighting device 2. It is assumed that the artwork is, for example, an artwork that is easily deteriorated by light.

[0016] The plurality of first LEDs 10 are connected in series to each other, for example. Each of the plurality of first LEDs 10 emits, for example, white light. Each of the plurality of first LEDs 10 is, for example, a white LED that combines a blue LED that emits blue light with a red phosphor and a green phosphor. Note that each of the plurality of first LEDs 10 emits white light, but is not limited to white light.

[0017] The second LEDs 20 are connected in series, for example. Each of the second LEDs 20 emits white light having a higher color gamut area ratio than the first LED 10. Each of the second LEDs 20 is a white LED including a red LED that emits red light, a green LED that emits green light, and a blue LED. Each of the second LEDs 20 emits white light, but is not limited to white light. As described in the JIS standard (JIS Z 8726), the "color gamut area ratio" is an index for evaluating the vividness of the color appearance of an object (illuminated object) illuminated by illumination light. Light with a high color gamut area ratio makes the color appearance of the illuminated object more vivid than light with a low color gamut area ratio.

[0018] The peak emission wavelength of a red LED is, for example, in the range of 600 nm to 640 nm, the peak emission wavelength of a green LED is, for example, in the range of 500 nm to 540 nm, and the peak emission wavelength of a blue LED is, for example, in the range of 430 nm to 470 nm.

[0019] The light color of the plurality of first LEDs 10 and the light color of the plurality of second LEDs 20 are the same type of light source color. More specifically, the light color of each of the plurality of first LEDs 10 and the light color of each of the plurality of second LEDs 20 are the same type of light source color. To be more specific, the light color of each of the plurality of first LEDs 10 and the light color of each of the plurality of second LEDs 20 are the same type of light source color among the types of light source colors defined in the JIS standard (JIS Z 9112), for example.

[0020] "Light source color" refers to the light source color specified in the JIS standard, and five types of light source colors are assumed: daylight, natural white, white, warm white, and incandescent white. The five types of light source colors are categorized by their correlated color temperature. The correlated color temperature of daylight is 5700K to 7100K. The correlated color temperature of natural white is 4600K to 5500K. The correlated color temperature of white is 3800K to 4500K. The correlated color temperature of warm white is 3250K to 3800K. The correlated color temperature of incandescent white is 2600K to 3250K. The unit of correlated color temperature, "K," is Kelvin.

[0021] Furthermore, the term "same type of light source color" is not limited to the completely same type of light source color, such as when the light color of both the multiple first LEDs 10 and the multiple second LEDs 20 is white. The term "same type of light source color" also includes, for example, a case where the light color of the multiple first LEDs 10 is white and the light color of the multiple second LEDs 20 is warm white, but the correlated color temperature of the multiple first LEDs 10 is 3800 K and the correlated color temperature of the multiple second LEDs 20 is also 3800 K. That is, it also includes a case where the correlated color temperatures of the multiple first LEDs 10 and the multiple second LEDs 20 are close to each other. In other words, it also includes a case where the difference (absolute value of the difference) between the correlated color temperature of the multiple first LEDs 10 and the correlated color temperature of the multiple second LEDs 20 is equal to or less than a predetermined value (e.g., 1000 K).

[0022] The lighting device 2 lights up the plurality of first LEDs 10. The lighting device 2 also lights up the plurality of second LEDs 20. In other words, the lighting device 2 lights up the plurality of first LEDs 10 and the plurality of second LEDs 20 individually.

[0023] The lighting device 2 includes, for example, a first lighting circuit 11, a second lighting circuit 21, a control circuit 30, a power supply circuit 40, and a setting unit 50. The lighting device 2 is electrically connected to, for example, an external power supply 70. The external power supply 70 is, for example, a commercial power supply.

[0024] The first lighting circuit 11 is electrically connected to the plurality of first LEDs 10. The first lighting circuit 11 lights up the plurality of first LEDs 10 in accordance with control from the control circuit 30. The first lighting circuit 11 also dims the plurality of first LEDs 10 in accordance with control from the control circuit 30.

[0025] The second lighting circuit 21 is electrically connected to the plurality of second LEDs 20. The second lighting circuit 21 lights up the plurality of second LEDs 20 in accordance with control from the control circuit 30. The second lighting circuit 21 also dims the plurality of second LEDs 20 in accordance with control from the control circuit 30.

[0026] The control circuit 30 is realized, for example, by a computer system having one or more processors and one or more memories. That is, the functions of the control circuit 30 are realized by the one or more processors executing a program stored in the memory. The program may be pre-stored in the memory, provided via a telecommunications line such as the Internet, or provided by being recorded on a non-transitory recording medium such as a memory card.

[0027] The control circuit 30 is electrically connected to the first lighting circuit 11 and the second lighting circuit 21. The control circuit 30 controls the first lighting circuit 11 and the second lighting circuit 21. The control circuit 30 has, for example, a determination unit 31. Details of the control by the control circuit 30 will be described later. Details of the determination unit 31 will also be described later.

[0028] The power supply circuit 40 is electrically connected to the first lighting circuit 11 and the second lighting circuit 21. The power supply circuit 40 is also electrically connected to the control circuit 30. The power supply circuit 40 is also electrically connected to an external power supply 70. The power supply circuit 40, for example, converts an AC voltage from the external power supply 70 into a first DC voltage. The power supply circuit 40 also converts the first DC voltage into a second DC voltage. The second DC voltage is, for example, smaller than the first DC voltage. The power supply circuit 40, for example, supplies the first DC voltage to the first lighting circuit 11 and the second lighting circuit 21. The power supply circuit 40 also supplies the second DC voltage to the control circuit 30.

[0029] The setting unit 50 is electrically connected to the control circuit 30. The setting unit 50 is configured to be able to change various settings of the lighting device A1. The control circuit 30 controls the first lighting circuit 11 and the second lighting circuit 21 in accordance with the settings made by the setting unit 50, for example.

[0030] The control circuit 30 controls the first lighting circuit 11 so that the first lighting circuit 11 dims the light of the plurality of first LEDs 10. More specifically, the control circuit 30 controls the first lighting circuit 11 so that the first lighting circuit 11 dims the light of the plurality of first LEDs 10 in accordance with the ratio of the luminous flux of white light emitted from the plurality of first LEDs 10.

[0031] For example, when the ratio of the luminous flux of white light emitted from the plurality of first LEDs 10 (hereinafter referred to as "first white light") is equal to or greater than a first reference value, the control circuit 30 controls the first lighting circuit 11 so that the current value of the first DC current output by the first lighting circuit 11 to the plurality of first LEDs 10 becomes equal to a first target value. In other words, when the ratio of the luminous flux of the first white light is equal to or greater than the first reference value, the control circuit 30 controls the first lighting circuit 11 so that the first lighting circuit 11 performs DC dimming of the plurality of first LEDs 10. The first reference value is, for example, a value (ratio) within a range of 5% to 10%. The first target value is a value (current value) corresponding to the ratio of the luminous flux of the first white light.

[0032] On the other hand, when the proportion of the luminous flux of the first white light is less than a first reference value, the control circuit 30 controls the first lighting circuit 11 so that the first lighting circuit 11 intermittently outputs a first DC current to the plurality of first LEDs 10. In other words, when the proportion of the luminous flux of the first white light is less than the first reference value, the control circuit 30 controls the first lighting circuit 11 so that the first lighting circuit 11 performs PWM dimming on the plurality of first LEDs 10. The frequency of the PWM dimming by the first lighting circuit 11 is, for example, within a range of 200 Hz or more and 2 kHz or less.

[0033] Furthermore, the control circuit 30 controls the second lighting circuit 21 so that the second lighting circuit 21 dims the light of the plurality of second LEDs 20. More specifically, the control circuit 30 controls the second lighting circuit 21 so that the second lighting circuit 21 dims the light of the plurality of second LEDs 20 in accordance with the proportion of the luminous flux of white light emitted from the plurality of second LEDs 20.

[0034] For example, when the ratio of the luminous flux of white light emitted from the plurality of second LEDs 20 (hereinafter referred to as "second white light") is equal to or greater than a second reference value, the control circuit 30 controls the second lighting circuit 21 so that the current value of the second DC current output by the second lighting circuit 21 to the plurality of second LEDs 20 becomes equal to a second target value. In other words, when the ratio of the luminous flux of the second white light is equal to or greater than the second reference value, the control circuit 30 controls the second lighting circuit 21 so that the second lighting circuit 21 performs DC dimming of the plurality of second LEDs 20. The second reference value is, for example, a value (ratio) within a range of 5% to 10%. Note that in this embodiment, the first reference value and the second reference value are the same value (e.g., 8%), but the first reference value and the second reference value may be different values. The second target value is a value (current value) corresponding to the ratio of the luminous flux of the second white light.

[0035] On the other hand, when the proportion of the luminous flux of the second white light is less than a second reference value, the control circuit 30 controls the second lighting circuit 21 so that the second lighting circuit 21 intermittently outputs a second DC current to the plurality of second LEDs 20. In other words, when the proportion of the luminous flux of the second white light is less than the second reference value, the control circuit 30 controls the second lighting circuit 21 so that the second lighting circuit 21 performs PWM dimming on the plurality of second LEDs 20. The frequency of the PWM dimming by the second lighting circuit 21 is, for example, within a range of 200 Hz to 2 kHz.

[0036] Specifically, as shown in FIG. 2, for example, when the luminous flux ratio of the first white light is 75% and the luminous flux ratio of the second white light is 25% (when the total luminous flux of the lighting device A1, described below, is 100%), the control circuit 30 controls the first lighting circuit 11 and the second lighting circuit 21 so that the first lighting circuit 11 performs DC dimming on the multiple first LEDs 10 and the second lighting circuit 21 performs DC dimming on the multiple second LEDs 20. Note that blue light B1 in FIG. 2 schematically represents the luminous flux ratio of the blue light of the multiple first LEDs 10. Green light G1 in FIG. 2 schematically represents the luminous flux ratio of the green light of the multiple first LEDs 10. Red light R1 in FIG. 2 schematically represents the luminous flux ratio of the red light of the multiple first LEDs 10. Blue light B2 in FIG. 2 schematically represents the luminous flux ratio of the blue light of the multiple second LEDs 20. 2 schematically represents the proportion of the luminous flux of the green light of the plurality of second LEDs 20. The red light R2 in FIG. 2 schematically represents the proportion of the luminous flux of the red light of the plurality of second LEDs 20.

[0037] 3, when the proportion of luminous flux of the first white light is 25% and the proportion of luminous flux of the second white light is 25% (when the total luminous flux of the lighting device A1 is 50%), the control circuit 30 controls the first lighting circuit 11 and the second lighting circuit 21 so that the first lighting circuit 11 performs DC dimming on the plurality of first LEDs 10 and the second lighting circuit 21 performs DC dimming on the plurality of second LEDs 20. Note that blue light B1, green light G1, and red light R1 in FIG. 3, like the blue light B1, green light G1, and red light R1 in FIG. 2, schematically represent the proportions of luminous flux of blue light B1, green light G1, and red light R1. Also, blue light B2, green light G2, and red light R2 in FIG. 3, like the blue light B2, green light G2, and red light R2 in FIG. 2, schematically represent the proportions of luminous flux of blue light B2, green light G2, and red light R2.

[0038] 4, for example, when the luminous flux ratio of the first white light is 8% and the luminous flux ratio of the second white light is 25% (when the total luminous flux of the lighting device A1 is 33%), the control circuit 30 controls the first lighting circuit 11 and the second lighting circuit 21 so that the first lighting circuit 11 performs DC dimming on the multiple first LEDs 10 and the second lighting circuit 21 performs DC dimming on the multiple second LEDs 20. Note that blue light B1, green light G1, and red light R1 in FIG. 4, like the blue light B1, green light G1, and red light R1 in FIG. 2, schematically represent the luminous flux ratios of the blue light B1, green light G1, and red light R1. Also, blue light B2, green light G2, and red light R2 in FIG. 4, like the blue light B2, green light G2, and red light R2 in FIG. 2, schematically represent the luminous flux ratios of the blue light B2, green light G2, and red light R2.

[0039] 5, when the luminous flux ratio of the first white light is 5% and the luminous flux ratio of the second white light is 25% (when the total luminous flux of the lighting device A1 is 30%), the control circuit 30 controls the first lighting circuit 11 and the second lighting circuit 21 so that the first lighting circuit 11 performs PWM dimming on the multiple first LEDs 10 and the second lighting circuit 21 performs DC dimming on the multiple second LEDs 20. Note that blue light B1, green light G1, and red light R1 in FIG. 5, similar to the blue light B1, green light G1, and red light R1 in FIG. 2, schematically represent the luminous flux ratios of the blue light B1, green light G1, and red light R1. Also, blue light B2, green light G2, and red light R2 in FIG. 5, similar to the blue light B2, green light G2, and red light R2 in FIG. 2, schematically represent the luminous flux ratios of the blue light B2, green light G2, and red light R2.

[0040] 6, when the proportion of luminous flux of the first white light is 2% and the proportion of luminous flux of the second white light is 4% (when the total luminous flux of the lighting device A1 is 6%), the control circuit 30 controls the first lighting circuit 11 and the second lighting circuit 21 so that the first lighting circuit 11 performs PWM dimming on the multiple first LEDs 10 and the second lighting circuit 21 performs PWM dimming on the multiple second LEDs 20. Here, in the lighting device A1, when both the first lighting circuit 11 and the second lighting circuit 21 perform PWM dimming as shown in FIG. 6, the frequency of the PWM dimming by the first lighting circuit 11 and the frequency of the PWM dimming by the second lighting circuit 21 are different. Note that the blue light B1, green light G1, and red light R1 in FIG. 6 schematically represent the proportions of luminous flux of the blue light B1, green light G1, and red light R1, similar to the blue light B1, green light G1, and red light R1 in FIG. 2. 2. Similarly to the blue light B2, green light G2, and red light R2 in FIG. 6, the blue light B2, green light G2, and red light R2 schematically represent the proportions of the luminous flux of the blue light B2, green light G2, and red light R2.

[0041] Therefore, the first lighting circuit 11 performs DC dimming on the multiple first LEDs 10 when the ratio of the luminous flux of the first white light is equal to or greater than a first reference value, and performs PWM dimming on the multiple first LEDs 10 when the ratio of the luminous flux of the first white light is less than the first reference value. Furthermore, the second lighting circuit 21 performs DC dimming on the multiple second LEDs 20 when the ratio of the luminous flux of the second white light is equal to or greater than a second reference value, and performs PWM dimming on the multiple second LEDs 20 when the ratio of the luminous flux of the second white light is less than the second reference value. This allows the lighting device A1 to stabilize the output of illumination light, thereby suppressing flickering due to blinking of the illumination light.

[0042] The control circuit 30 controls the first lighting circuit 11 so that the first lighting circuit 11 dims the light of the first LEDs 10 in accordance with the total luminous flux of light obtained by combining the light emitted from the first LEDs 10 and the light emitted from the second LEDs 20 (hereinafter, sometimes referred to as the "total luminous flux of the first LEDs 10 and the second LEDs 20"). The control circuit 30 also controls the second lighting circuit 21 so that the second lighting circuit 21 dims the light of the second LEDs 20 in accordance with the total luminous flux of the first LEDs 10 and the second LEDs 20. In other words, the control circuit 30 controls the first lighting circuit 11 and the second lighting circuit 21 so that the first lighting circuit 11 and the second lighting circuit 21 individually dim the light of the corresponding LEDs (the first LEDs 10 and the second LEDs 20) in accordance with the total luminous flux of the first LEDs 10 and the second LEDs 20. In other words, the lighting device 2 is configured to individually adjust the brightness of the plurality of first LEDs 10 and the plurality of second LEDs 20 according to the total luminous flux of the plurality of first LEDs 10 and the plurality of second LEDs 20.

[0043] When the total luminous flux of the first LEDs 10 and the second LEDs 20 is greater than a threshold, the lighting device 2 individually dims the first LEDs 10 and the second LEDs 20 so that the proportion of the luminous flux of the first LEDs 10 in the total luminous flux increases. In other words, as shown in FIG. 2, when the total luminous flux of the first LEDs 10 and the second LEDs 20 is greater than the threshold, the lighting device 2 individually dims the first LEDs 10 and the second LEDs 20 so that the proportion of the luminous flux of the first white light in the total luminous flux increases compared to the proportion of the luminous flux of the second white light in the total luminous flux. The threshold is, for example, 50%. The threshold is pre-stored in the memory of the control circuit 30. In this embodiment, the control circuit 30 compares the total luminous flux of the first LEDs 10 and the second LEDs 20 with the threshold to determine, for example, whether the total luminous flux of the first LEDs 10 and the second LEDs 20 is greater than the threshold.

[0044] Furthermore, when the total luminous flux of the plurality of first LEDs 10 and the plurality of second LEDs 20 is smaller than the threshold, the lighting device 2 individually dims the plurality of first LEDs 10 and the plurality of second LEDs 20 so that the proportion of the luminous flux of the plurality of second LEDs 20 in the total luminous flux becomes larger. In other words, as shown in Figures 4 to 6, for example, when the total luminous flux of the plurality of first LEDs 10 and the plurality of second LEDs 20 is smaller than the threshold, the lighting device 2 individually dims the plurality of first LEDs 10 and the plurality of second LEDs 20 so that the proportion of the luminous flux of the second white light in the total luminous flux becomes larger than the proportion of the luminous flux of the first white light in the total luminous flux.

[0045] Furthermore, when the total luminous flux of the plurality of first LEDs 10 and the plurality of second LEDs 20 is equal to the threshold value, the lighting device 2 individually dims the plurality of first LEDs 10 and the plurality of second LEDs 20 so that the proportion of the luminous flux of the plurality of first LEDs 10 in the total luminous flux is equal to the proportion of the luminous flux of the plurality of second LEDs 20 in the total luminous flux. In other words, as shown in Fig. 3, for example, when the total luminous flux of the plurality of first LEDs 10 and the plurality of second LEDs 20 is equal to the threshold value, the lighting device 2 individually dims the plurality of first LEDs 10 and the plurality of second LEDs 20 so that the proportion of the luminous flux of the first white light in the total luminous flux is equal to the proportion of the luminous flux of the second white light in the total luminous flux.

[0046] Note that, for ease of explanation, the dimming of the multiple first LEDs 10 and multiple second LEDs 20 shown in Figures 2 to 6 is a dimming that schematically shows an example in which the threshold value is 50%, and actual dimming does not necessarily result in the dimming of the multiple first LEDs 10 and multiple second LEDs 20 shown in Figures 2 to 6.

[0047] Therefore, in the lighting device A1, when the total luminous flux of the first LEDs 10 and the second LEDs 20 is greater than the threshold, the luminous flux of the first white light is greater than the luminous flux of the second white light. Therefore, in the lighting device A1, for example, when the total luminous flux of the first LEDs 10 and the second LEDs 20 is large (e.g., when the total luminous flux is the same as the luminous flux of the reference light), the color gamut area ratio K1 of the white light emitted from the first LEDs 10 and the second LEDs 20 can be made the same as the color gamut area ratio K0 of the reference light, as shown in FIG. 7. Note that "reference light" refers to natural light. Furthermore, the color gamut area ratio K1 and the color gamut area ratio K0 are each represented by the area of ​​an octagon in FIG. 7.

[0048] Furthermore, in the lighting device A1, when the total luminous flux of the first LEDs 10 and the second LEDs 20 is smaller than the threshold value, the luminous flux of the second white light becomes larger than the luminous flux of the first white light. Therefore, in the lighting device A1, for example, when the total luminous flux of the first LEDs 10 and the second LEDs 20 is small (for example, when the total luminous flux is lower than the luminous flux of the reference light), the color gamut area ratio K1 of the white light emitted from the first LEDs 10 and the second LEDs 20 can be made the same as the color gamut area ratio K0 of the reference light, as shown in FIG.

[0049] On the other hand, in the lighting device of Comparative Example 1 equipped with only one type of LED (e.g., a plurality of first LEDs 10), when the total luminous flux of the plurality of first LEDs 10 is small (e.g., when the total luminous flux of the plurality of first LEDs 10 is lower than the luminous flux of the reference light), the color gamut area ratio K2 of the white light emitted from the plurality of first LEDs 10 becomes smaller than the color gamut area ratio K0 of the reference light, as shown in FIG. 8. As a result, in the lighting device of Comparative Example 1, when the total luminous flux of the plurality of first LEDs 10 is small, the color of the illuminated object (e.g., an artwork) appears dull. That is, in the lighting device of Comparative Example 1, the color of the illuminated object under low illuminance differs from the color of the illuminated object under standard illuminance. Note that the "standard illuminance" is assumed to be, for example, an illuminance of 1000 lux. Furthermore, "low illuminance" is an illuminance lower than the standard illuminance. Furthermore, the lighting device of Comparative Example 1 is assumed to have, for example, a high general color rendering index. Moreover, each of the color gamut area ratios K2 and K0 is represented by the area of ​​an octagon in Fig. 8. The color gamut area ratio K0 in Fig. 8 is the same as the color gamut area ratio K0 in Fig. 7.

[0050] Furthermore, in the illumination device of Comparative Example 2, which includes only one other type of LED (e.g., a plurality of second LEDs 20), when the total luminous flux of the plurality of second LEDs 20 is large (e.g., when the total luminous flux of the plurality of second LEDs 20 is the same as the luminous flux of the reference light), the color gamut area ratio K3 of the white light emitted from the plurality of second LEDs 20 becomes larger than the color gamut area ratio K0 of the reference light, as shown in FIG. 9. As a result, in the illumination device of Comparative Example 2, when the total luminous flux of the plurality of second LEDs 20 is large, the color of the irradiated object appears more vivid than the color of the irradiated object under the reference illumination. In other words, in the illumination device of Comparative Example 2, the color of the irradiated object is reproduced more vividly. For example, compared to a person's memory (so-called memory color), the color of the irradiated object may appear too vivid and somewhat unnatural. Note that the illumination device of Comparative Example 2 is assumed to have a low general color rendering index. Furthermore, the color gamut area ratio K3 and the color gamut area ratio K0 are each represented by the area of ​​an octagon in FIG. 9. The color gamut area ratio K0 in FIG. 9 is the same as the color gamut area ratio K0 in FIG.

[0051] That is, in the lighting devices of Comparative Examples 1 and 2, the color of the illuminated object may appear differently from the color of the illuminated object under the reference illuminance.

[0052] In the lighting device A1 of this embodiment, for example, when the total luminous flux of the plurality of first LEDs 10 and the plurality of second LEDs 20 is large, the plurality of first LEDs 10 emit a large amount of white light, so that the color appearance of the irradiated object is the same as that of the irradiated object under the standard illuminance (see FIG. 7). Furthermore, in the lighting device A1, for example, when the total luminous flux of the plurality of first LEDs 10 and the plurality of second LEDs 20 is small, the plurality of second LEDs 20 emit a large amount of white light (emits a large amount of white light having a higher color gamut area ratio than the plurality of first LEDs 10), so that the color appearance of the irradiated object under low illuminance is the same as that of the irradiated object under the standard illuminance (see FIG. 7). Therefore, the lighting device A1 of this embodiment can faithfully reproduce the color of the irradiated object under the standard illuminance, even under low illuminance. Therefore, the lighting device A1 can faithfully reproduce the color of the irradiated object. Furthermore, since the lighting device A1 can faithfully reproduce the color of the illuminated object even under low illumination, there is no need to increase the illumination intensity in order to faithfully reproduce the color of the illuminated object, which allows the lighting device A1 to achieve low power consumption.

[0053] In addition, in the lighting device A1, each of the second LEDs 20 is a white LED including a red LED, a green LED, and a blue LED. This makes it possible to adjust the color gamut area ratio of the white light emitted from the second LEDs 20, for example, and more faithfully reproduce the color of the illuminated object.

[0054] Furthermore, in the lighting device A1, the light color of the plurality of first LEDs 10 and the light color of the plurality of second LEDs 20 are the same type of light source color. This makes it easier to dim the plurality of first LEDs 10 and the plurality of second LEDs 20 in the lighting device A1 compared to, for example, a case where the light color of the plurality of first LEDs 10 and the light color of the plurality of second LEDs 20 are different types of light source colors.

[0055] The lighting device A1 also illuminates artworks in art galleries or museums. Therefore, the lighting device A1 can faithfully reproduce the color of the illuminated object even under low illuminance, making it possible to faithfully reproduce the color of the artwork, for example, and to prevent the artwork from being deteriorated by the illumination light.

[0056] Here, it is preferable that the lighting device 2 individually dims the plurality of first LEDs 10 and the plurality of second LEDs 20 based on the condition of the following formula 1, where Ga1 is the color gamut area ratio of the plurality of first LEDs 10, Ga2 is the color gamut area ratio of the plurality of second LEDs 20, φ1 is the luminous flux of the plurality of first LEDs 10, φ2 is the luminous flux of the plurality of second LEDs 20, and φ is the total luminous flux of the plurality of first LEDs 10 and the plurality of second LEDs 20. Fig. 10 is a graph illustrating formula 1, in which the color gamut area ratio of the plurality of first LEDs 10 is 100 (Ga1 = 100) and the color gamut area ratio of the plurality of second LEDs 20 is 120 (Ga2 = 120).

[0057]

number

[0058] For example, the control circuit 30 calculates the luminous flux of the plurality of first LEDs 10 and the luminous flux of the plurality of second LEDs 20, which corresponds to the total luminous flux of the plurality of first LEDs 10 and the plurality of second LEDs 20, based on the conditions of Equation 1. Furthermore, the control circuit 30 controls the first lighting circuit 11 and the second lighting circuit 21 based on the calculated luminous flux of the plurality of first LEDs 10 and the calculated luminous flux of the plurality of second LEDs 20, so that the first lighting circuit 11 and the second lighting circuit 21 individually dim the corresponding plurality of LEDs (first LEDs 10 and second LEDs 20). Therefore, in the lighting device A1, the lighting device 2 individually dims the plurality of first LEDs 10 and the plurality of second LEDs 20 based on the conditions of Equation 1, making it possible to more faithfully reproduce the color of the illuminated object.

[0059] Furthermore, it is preferable that the lighting device 2 individually dims the plurality of first LEDs 10 and the plurality of second LEDs 20 based on the condition of the following formula 2, where n is the luminous flux ratio, which is the ratio between the luminous flux of the plurality of first LEDs 10 and the luminous flux of the plurality of second LEDs 20, a is a first constant within the range of 7.5 to 12.5, and b is a second constant within the range of 62.5 to 77.5. Note that the value of n is greater than 0 and less than 1.

[0060]

number

[0061] For example, the control circuit 30 calculates a luminous flux ratio corresponding to the total luminous flux of the plurality of first LEDs 10 and the plurality of second LEDs 20 based on the condition of Equation 2. Furthermore, the control circuit 30 controls the first lighting circuit 11 and the second lighting circuit 21 based on the calculated luminous flux ratio so as to individually dim the corresponding plurality of LEDs (first LEDs 10 and second LEDs 20). Therefore, in the lighting device A1, the lighting device 2 individually dims the plurality of first LEDs 10 and the plurality of second LEDs 20 based on the condition of Equation 2, making it possible to more faithfully reproduce the color of the illuminated object.

[0062] Here, it is more preferable that the relationship between the first constant and the second constant (the relationship between a and b in Equation 2) satisfies the condition of the following Equation 3. This enables the lighting device A1 to reproduce the color of the illuminated object more faithfully.

[0063]

number

[0064] The setting unit 50 may be configured to set a luminous flux ratio between the luminous flux of the plurality of first LEDs 10 and the luminous flux of the plurality of second LEDs 20. More specifically, the setting unit 50 sets the value of n in Equation 2. In this case, the control circuit 30 controls the first lighting circuit 11 and the second lighting circuit 21 according to the luminous flux ratio set by the setting unit 50. That is, the lighting device 2 individually dims the plurality of first LEDs 10 and the plurality of second LEDs 20 based on the luminous flux ratio set by the setting unit 50 and the condition of Equation 2. As a result, in the lighting device A1, for example, the luminous flux ratio calculated by the control circuit 30 can be adjusted by setting the luminous flux ratio in the setting unit 50. Therefore, the lighting device A1 can more faithfully reproduce the color of the illuminated object.

[0065] Furthermore, in the lighting device A1, for example, by adopting the luminous flux ratio set by the setting unit 50, it is not necessary to perform calculation processing of the luminous flux ratio by the control circuit 30, and therefore it is possible to achieve lower power consumption than when the luminous flux ratio calculated by the control circuit 30 is used.

[0066] The setting unit 50 may also be configured to be able to set the degree of color reproducibility of the irradiated object under low illuminance. For example, the setting unit 50 sets one of three levels, "high," "medium," and "low," as the degree of color reproducibility of the irradiated object under low illuminance. In this case, the determination unit 31 of the control circuit 30 determines the first and second constants according to the degree of color reproducibility of the irradiated object under low illuminance set by the setting unit 50. Note that the "degree of color reproducibility of the irradiated object" refers to a ratio indicating how faithfully the color of the irradiated object can be reproduced relative to the color of the actual object.

[0067] For example, when the degree of color reproducibility under low illuminance set by the setting unit 50 is "high," the determination unit 31 sets the first constant to 12.5 and the second constant to 62.5. When the degree of color reproducibility under low illuminance set by the setting unit 50 is "medium," the determination unit 31 sets the first constant to 10.0 and the second constant to 70.0. When the degree of color reproducibility under low illuminance set by the setting unit 50 is "low," the determination unit 31 sets the first constant to 7.5 and the second constant to 77.5.

[0068] The control circuit 30 controls the first lighting circuit 11 and the second lighting circuit 21 according to the first and second constants determined by the determination unit 31. That is, the lighting device 2 individually dims the plurality of first LEDs 10 and the plurality of second LEDs 20 based on the first and second constants determined by the determination unit 31 and the condition of Equation 2. In this way, the lighting device A1 determines the values ​​of the first and second constants in Equation 2, making it possible to more faithfully reproduce the color of the illuminated object.

[0069] In this embodiment, since the lighting device A1 is a lighting device that illuminates artworks in an art gallery or museum, it is desirable that the degree of color reproducibility of the illuminated object under low illuminance, which is set by the setting unit 50, be "high."

[0070] When artworks (e.g., paintings) exhibited in art galleries or museums are illuminated at a standard illuminance, the paints and other elements may be deteriorated by the illumination light. Therefore, when illuminating artworks in art galleries or museums, the lighting device A1 must illuminate the artworks at a low illuminance. Therefore, as described above, the lighting device A1 emits a large amount of white light from the second LEDs 20 when the total luminous flux of the first LEDs 10 and the second LEDs 20 is small. Therefore, it is desirable that the degree of color reproducibility of the illuminated object under low illuminance, as set by the setting unit 50, be "high." This allows the color appearance of the illuminated object under low illuminance to be the same as the color appearance of the illuminated object under standard illuminance, making the lighting device A1 effective for illuminating artworks in art galleries or museums.

[0071] (2) Lighting equipment A lighting fixture E1 equipped with a lighting device A1 according to this embodiment will be described below with reference to FIG.

[0072] The lighting fixture E1 is a lighting fixture installed in, for example, an art gallery or museum. The lighting fixture E1 is, for example, a spotlight. The lighting fixture E1 is configured to be detachable from, for example, a lighting wiring duct (also called a lighting duct) installed on a ceiling or the like. In the following description, unless otherwise specified, the first direction D1, second direction D2, and third direction D3 indicated by arrows in FIG. 11 are defined as the front-to-back direction, left-to-right direction, and up-to-down direction of the lighting fixture E1 of the embodiment. However, the front-to-back direction, left-to-right direction, and up-to-down direction are used for convenience to facilitate understanding of the description of the embodiment and do not define the directions when the lighting fixture E1 of the embodiment is used. Furthermore, the arrows indicating "D1," "D2," and "D3" in FIG. 11 are merely shown for explanatory purposes and do not have any physical substance.

[0073] The lighting fixture E1 includes, for example, a lighting device A1 (see FIG. 1), a fixture body 65, an arm 5, and a plug unit 8. Note that in FIG. 11, the lighting device A1 is arranged inside the fixture body 65, and therefore the lighting device A1 is not visible.

[0074] The fixture body 65 houses the lighting device A1. The fixture body 65 has, for example, a main body portion 60, an end cover 63, and a lens unit 3. The main body portion 60 includes, for example, a first main body portion 61 and a second main body portion 62.

[0075] The first main body portion 61 houses, for example, the lens unit 3. The first main body portion 61 has, for example, a cylindrical shape. The material of the first main body portion 61 is, for example, a metal (for example, an aluminum alloy, etc.).

[0076] The second main body 62 houses, for example, the lighting device A1. More specifically, the second main body 62 houses, for example, a light source unit and a lighting device 2 (see FIG. 1). Note that in FIG. 11, the light source unit and the lighting device 2 are not visible because they are arranged inside the second main body 62.

[0077] The light source unit includes, for example, a plurality of first LEDs 10 (see FIG. 1), a plurality of second LEDs 20 (see FIG. 1), and a substrate. The plurality of first LEDs 10 and the plurality of second LEDs 20 are arranged on one surface of the substrate. The second body portion 62 is, for example, cylindrical. The material of the second body portion 62 is, for example, metal (e.g., aluminum alloy). The diameter of the second body portion 62 is the same as the diameter of the first body portion 61. The length of the second body portion 62 in the axial direction (first direction D1) is longer than the length of the first body portion 61 in the axial direction (first direction D1). The second body portion 62 is connected to the first body portion 61 so that the central axis F2 of the second body portion 62 coincides with the central axis F1 of the first body portion 61. The first body portion 61 and the second body portion 62 are connected so that the central axis F1 of the first body portion 61 and the central axis F2 of the second body portion 62 coincide with the optical axis C1 of the fixture body 65. The optical axis C1 of the fixture body 65 coincides with the optical axis of the lens unit 3 (more specifically, the lens) housed in the first body portion 61 of the fixture body 65.

[0078] The plurality of first LEDs 10 are arranged on the one surface of the substrate so as to surround the optical axis C1 of the fixture body 65. Furthermore, the plurality of second LEDs 20 are arranged on the one surface of the substrate so as to surround the plurality of first LEDs 10 arranged around the optical axis C1 of the fixture body 65. In other words, the plurality of first LEDs 10 are arranged around the optical axis C1 of the fixture body 65. Furthermore, the plurality of second LEDs 20 are arranged around the plurality of first LEDs 10.

[0079] The lighting device 2 is electrically and mechanically connected to the light source unit via, for example, a connection cable.

[0080] The end cover 63 is configured to hold the arm 5 and close the rear end of the second main body portion 62 in the front-rear direction (first direction D1). The end cover 63 is made of, for example, metal (such as aluminum alloy). The second main body portion 62 has a slit 64 through which the arm 5 held by the end cover 63 is inserted. The slit 64 is provided in the peripheral wall of the second main body portion 62. The width of the slit 64 in the left-right direction (second direction D2) is wider than the width of the arm 5 in the left-right direction (second direction D2).

[0081] The lens unit 3 has, for example, a lens, a lens holder, a cover 32, and a rotor 33. Note that in Figure 11, the lens and the lens holder are not visible because they are arranged inside the rotor 33.

[0082] The lens is, for example, a Fresnel lens. The lens is made of, for example, a light-transmitting resin. Examples of the light-transmitting resin include silicone resin, acrylic resin, and polycarbonate resin. Note that the lens is not limited to being made of a light-transmitting resin, and may be made of any light-transmitting material, such as glass.

[0083] The lens holder holds the lens so as to surround the lens, and is, for example, annular in shape and made of, for example, resin.

[0084] The cover 32 is attached to the rotor 33 so as to cover a part (front surface) of the rotor 33. The cover 32 is, for example, disk-shaped. The cover 32 is made of, for example, a translucent resin.

[0085] The rotor 33 includes a cylindrical portion and an operating portion 331. The cylindrical portion houses the lens and the lens unit. The cylindrical portion is made of a material such as resin. The cylindrical portion is connected to the first main body portion 61 so that the central axis of the cylindrical portion coincides with the central axis F1 of the first main body portion 61. In other words, the cylindrical portion is connected to the first main body portion 61 so that the central axis of the cylindrical portion coincides with the optical axis C1 of the device body 65.

[0086] The operating portion 331 is attached to the front end portion of the cylindrical portion in the front-rear direction (first direction D1). The operating portion 331 has an annular shape. The operating portion 331 is made of, for example, resin.

[0087] The arm 5 is, for example, rod-shaped. The material of the arm 5 is, for example, metal (such as aluminum alloy). A first end (lower end) of the arm 5 in the vertical direction (third direction D3) is held by the end cover 63. A second end (upper end) of the arm 5 in the vertical direction is rotatably held by the plug unit 8. Therefore, the fixture body 65 can rotate within a predetermined range within a plane parallel to the ceiling surface around the rotation axis of the arm 5. The rotation axis of the arm 5 is parallel to the vertical direction of the arm 5.

[0088] The plug unit 8 is configured to be mechanically and electrically connectable to, for example, a lighting wiring duct. The plug unit 8 rotatably holds the upper end of the arm 5. In the lighting fixture E1, AC voltage supplied from an external power source 70 (see FIG. 1) is supplied to the power supply circuit 40 of the lighting device A1 housed in the second main body 62 via the lighting wiring duct, the plug unit 8, and the arm 5.

[0089] The lighting fixture E1 includes the lighting device A1 and a fixture body 65. This allows the lighting fixture E1 to faithfully reproduce the color of an illuminated object.

[0090] Furthermore, in the lighting device E1, the multiple first LEDs 10 are arranged around the optical axis C1 of the device body 65, and the multiple second LEDs 20 are arranged around the multiple first LEDs 10. Therefore, in the lighting device E1, it is possible to make the color appearance of the peripheral part of the area irradiated with illumination light (illuminated area) the same as the color appearance of the central part of the illuminated area.

[0091] (3) Variations 1 is configured to individually dim the first LEDs 10 and the second LEDs 20 in accordance with a comparison result between the total luminous flux of the first LEDs 10 and the second LEDs 20 and the threshold value, but is not limited to this configuration. For example, the lighting device 2 may be configured to individually dim the first LEDs 10 and the second LEDs 20 in accordance with an increase in the total luminous flux of the first LEDs 10 and the second LEDs 20.

[0092] Specifically, the lighting device 2 individually dims the plurality of first LEDs 10 and the plurality of second LEDs 20 so that the proportion of the luminous flux of the plurality of first LEDs 10 in the total luminous flux increases as the total luminous flux of the plurality of first LEDs 10 and the plurality of second LEDs 20 increases. In short, in the lighting device A1, the luminous flux of the first white light becomes greater than the luminous flux of the second white light as the total luminous flux of the plurality of first LEDs 10 and the plurality of second LEDs 20 increases.

[0093] Each of the plurality of first LEDs 10 is a white LED that combines a blue LED with a red phosphor and a green phosphor, but is not limited to this white LED. Each of the plurality of first LEDs 10 may be a white LED that combines, for example, a red LED with low color purity that combines a blue LED with a red phosphor, a green LED with low color purity that combines a blue LED with a green phosphor, and a blue LED with low color purity that combines a blue LED with a blue phosphor.

[0094] The power supply circuit 40 supplies the second DC voltage to the control circuit 30, but may supply the first DC voltage to the control circuit 30. In this case, the power supply circuit 40 does not have the function of converting the first DC voltage into the second DC voltage.

[0095] The setting unit 50 is electrically connected to the control circuit 30, but may also communicate with the control circuit 30 wirelessly using radio waves as a medium, for example.

[0096] The lighting device A1 includes two types of LEDs (first LED 10 and second LED 20), but may include, for example, three types of LEDs or four types of LEDs. In short, it is sufficient for the lighting device A1 to include at least two types of LEDs 10 and 20.

[0097] Although the lighting device A1 includes a plurality of first LEDs 10, it may include a single first LED 10. Furthermore, although the lighting device A1 includes a plurality of second LEDs 20, it may include a single second LED 20.

[0098] Although the lighting device 2 includes a setting unit 50 in this embodiment, it does not necessarily have to include the setting unit 50. Although the control circuit 30 includes a determination unit 31 in this embodiment, it does not necessarily have to include the determination unit 31.

[0099] The lighting device A1 is a lighting device that illuminates artworks in an art gallery or museum, but may also be a lighting device that illuminates a stage, for example.

[0100] Lighting devices for illuminating a stage such as a play may illuminate performers and backgrounds at low illuminance, and conventional lighting devices with a high general color rendering index (such as the lighting device of Comparative Example 1) may be used. Therefore, with conventional lighting devices, there is a risk that the appearance of the colors of the performers and background under low illuminance may differ from the appearance of the colors of the performers and background under standard illuminance.

[0101] On the other hand, the lighting device A1 emits a large amount of white light from the multiple second LEDs 20 in low illuminance, so the colors of the performers and background appear the same under low illuminance as they do under standard illuminance. Therefore, the lighting device A1 is also effective for lighting a stage.

[0102] The lighting fixture E1 is a lighting fixture installed inside an art gallery or museum, but may also be a lighting fixture that illuminates a stage, for example.

[0103] A conventional lighting fixture for illuminating a stage may be a spotlight. When a conventional lighting fixture illuminates a stage with a large illumination area, the center of the illumination area may have a standard illuminance and the peripheral area of ​​the illumination area may have a low illuminance. Therefore, with a conventional lighting fixture, the color appearance of the peripheral area of ​​the illumination area may differ from the color appearance of the central area of ​​the illumination area.

[0104] On the other hand, in the lighting fixture E1, the first LEDs 10 are arranged around the optical axis C1 of the fixture body 65, and the second LEDs 20 are arranged around the first LEDs 10, so that the color appearance of the peripheral part of the illuminated area is the same as the color appearance of the central part of the illuminated area. Therefore, the lighting fixture E1 is also effective when illuminating a stage.

[0105] Furthermore, the lighting device A1 may be a lighting device for illuminating a stage, or may be a lighting device for use in a home, for example. In this case, it is desirable that the degree of color reproducibility of the illuminated object under low illuminance set by the setting unit 50 be "low."

[0106] Furthermore, the lighting fixture E1 may be a lighting fixture for a home, for example, in addition to a lighting fixture for illuminating a stage.

[0107] The lighting fixture E1 is not limited to a spotlight and may be, for example, a downlight. The material of the first main body 61 is not limited to metal and may be, for example, resin. The material of the second main body 62 is not limited to metal and may be, for example, resin. The material of the end cover 63 is not limited to metal and may be, for example, resin. The material of the arm 5 is not limited to metal and may be, for example, resin.

[0108] The above-described embodiments and modifications are merely a part of the various embodiments and modifications of the present disclosure.

[0109] (Aspect) The present specification discloses the following aspects.

[0110] An illumination device (A1) according to a first aspect includes at least two types of LEDs (10, 20) and a lighting device (2). The lighting device (2) individually lights up the at least two types of LEDs (10, 20). The at least two types of LEDs (10, 20) include a first LED (10) and a second LED (20) that emits light having a color gamut area ratio higher than that of the first LED (10). The lighting device (2) is configured to be able to individually dim the first LED (10) and the second LED (20) in accordance with a total luminous flux of light that is a combination of light emitted from the first LED (10) and light emitted from the second LED (20). When the total luminous flux is greater than a threshold, the lighting device (2) individually dims the first LED (10) and the second LED (20) so that the proportion of the luminous flux of the first LED (10) in the total luminous flux increases. When the total luminous flux is smaller than the threshold value, the lighting device (2) individually dims the first LED (10) and the second LED (20) so that the proportion of the luminous flux of the second LED (20) in the total luminous flux becomes larger.When the total luminous flux is equal to the threshold value, the lighting device (2) individually dims the first LED (10) and the second LED (20) so that the proportion of the luminous flux of the first LED (10) and the proportion of the luminous flux of the second LED (20) become equal.

[0111] According to this aspect, it is possible to faithfully reproduce the color of the illuminated object.

[0112] In the illumination device (A1) according to the second aspect, in the first aspect, the lighting device (2) individually dims the first LED (10) and the second LED (20) based on the condition of the following formula 1, where Ga1 is the color gamut area ratio of the first LED (10), Ga2 is the color gamut area ratio of the second LED (20), φ1 is the luminous flux of the first LED (10), φ2 is the luminous flux of the second LED (20), and φ is the total luminous flux.

[0113]

number

[0114] According to this aspect, it is possible to more faithfully reproduce the color of the illuminated object.

[0115] In the illumination device (A1) according to the third aspect, in the second aspect, the lighting device (2) individually dims the first LED (10) and the second LED (20) based on the condition of the following formula 2, where a luminous flux ratio that is the ratio between the luminous flux of the first LED (10) and the luminous flux of the second LED (20) is (1-n):n, a is a first constant that is within a range of 7.5 to 12.5, and b is a second constant that is within a range of 62.5 to 77.5.

[0116]

number

[0117] According to this aspect, it is possible to reproduce the color of the illuminated object more faithfully.

[0118] In a lighting device (A1) according to a fourth aspect, the lighting device (2) of the third aspect includes a setting unit (50). The setting unit (50) sets a luminous flux ratio. The lighting device (2) individually dims the first LED (10) and the second LED (20) based on the luminous flux ratio set by the setting unit (50) and the condition of Equation 2.

[0119] According to this aspect, it is possible to reproduce the color of the illuminated object more faithfully.

[0120] The lighting device (A1) according to a fifth aspect is the lighting device (A1) of the third or fourth aspect, wherein the lighting device (2) has a setting unit (50) and a determination unit (31). The setting unit (50) sets a degree of color reproducibility of an illuminated object under low illuminance that is lower than a reference illuminance. The determination unit (31) determines a first constant and a second constant according to the degree set by the setting unit (50). The lighting device (2) individually dims the first LED (10) and the second LED (20) based on the first constant and the second constant determined by the determination unit (31) and the condition of Equation 2.

[0121] According to this aspect, it is possible to reproduce the color of the illuminated object more faithfully.

[0122] The lighting device (A1) according to a sixth aspect is any one of the first to fifth aspects, wherein the second LED (20) is a white LED including a red LED that emits red light, a green LED that emits green light, and a blue LED that emits blue light.

[0123] According to this aspect, it is possible to more faithfully reproduce the color of the illuminated object.

[0124] The illumination device (A1) according to a seventh aspect is any one of the first to sixth aspects, wherein the light color of the first LED (10) and the light color of the second LED (20) are the same type of light source color.

[0125] According to this aspect, it is easier to control, for example, the plurality of first LEDs (10) and the plurality of second LEDs (20) compared to when the light colors of the plurality of first LEDs (10) and the plurality of second LEDs (20) are different types of light source colors.

[0126] The lighting device (A1) according to an eighth aspect is in any one of the first to seventh aspects and illuminates an artwork in an art gallery or museum.

[0127] According to this aspect, for example, it is possible to faithfully reproduce the color of the artwork and to prevent the artwork from being deteriorated by illumination light.

[0128] An illumination device (A1) according to a ninth aspect includes at least two types of LEDs (10, 20) and a lighting device (2). The lighting device (2) individually lights up the at least two types of LEDs (10, 20). The at least two types of LEDs (10, 20) include a first LED (10) and a second LED (20) that emits light having a color gamut area ratio higher than that of the first LED (10). The lighting device (2) is configured to be able to individually dim the first LED (10) and the second LED (20) in accordance with a total luminous flux of light that is a combination of light emitted from the first LED (10) and light emitted from the second LED (20). The lighting device (2) individually dims the first LED (10) and the second LED (20) so that the proportion of the luminous flux of the first LED (10) in the total luminous flux increases as the total luminous flux increases.

[0129] According to this aspect, it is possible to faithfully reproduce the color of the illuminated object.

[0130] A lighting fixture (E1) according to a tenth aspect includes the lighting device (A1) according to the first or ninth aspect and a fixture body (65). The fixture body (65) houses the lighting device (A1).

[0131] According to this aspect, it is possible to faithfully reproduce the color of the illuminated object.

[0132] A lighting fixture (E1) according to an eleventh aspect is the lighting device (A1) of the tenth aspect, wherein the lighting device (A1) includes a plurality of first LEDs (10) and a plurality of second LEDs (20). The plurality of first LEDs (10) are arranged around an optical axis (C1) of the fixture body (65). The plurality of second LEDs (20) are arranged around the plurality of first LEDs (10).

[0133] According to this aspect, it is possible to make the color appearance in the peripheral part of the illuminated area the same as the color appearance in the central part of the illuminated area. [Explanation of symbols]

[0134] 2 Lighting device 10 1st LED (LED) 20 Second LED (LED) 31 Decision Section 50 Setting section 65 Equipment body A1 Lighting Equipment C1 optical axis E1 lighting fixture

Claims

1. At least two types of LEDs; a lighting device that lights up the at least two types of LEDs individually, The at least two types of LEDs are A first LED; a second LED that emits light having a color gamut area ratio higher than that of the first LED; The lighting device is The first LED and the second LED are configured to be individually dimmable according to a total luminous flux of light obtained by combining the light emitted from the first LED and the light emitted from the second LED, If the total luminous flux is greater than a threshold, individually dimming the first LED and the second LED so that a proportion of the luminous flux of the first LED in the total luminous flux is increased; When the total luminous flux is smaller than the threshold, individually dimming the first LED and the second LED so that a proportion of the luminous flux of the second LED in the total luminous flux is increased; If the total luminous flux is equal to the threshold, individually dimming the first LED and the second LED so that the proportion of luminous flux of the first LED and the proportion of luminous flux of the second LED are equal. Lighting equipment.

2. The lighting device individually dims the first LED and the second LED based on the condition of the following formula 1, where Ga1 is a color gamut area ratio of the first LED, Ga2 is a color gamut area ratio of the second LED, φ1 is a luminous flux of the first LED, φ2 is a luminous flux of the second LED, and φ is the total luminous flux: The lighting device according to claim 1 . [Equation 1]

3. The lighting device individually dims the first LED and the second LED based on the condition of the following formula 2, where n is a luminous flux ratio that is a ratio of the luminous flux of the first LED to the luminous flux of the second LED, a is a first constant that is within a range of 7.5 to 12.5, and b is a second constant that is within a range of 62.5 to 77.5:

3. The lighting device according to claim 2. [Equation 2]

4. The lighting device is a setting unit that sets the luminous flux ratio, Dimming the first LED and the second LED individually based on the luminous flux ratio set by the setting unit and the condition of Equation 2.

4. The lighting device according to claim 3.

5. The lighting device is a setting unit that sets a degree of color reproducibility of the illuminated object under low illuminance that is lower than the reference illuminance; a determination unit that determines the first constant and the second constant in accordance with the degree set by the setting unit, Dimming the first LED and the second LED individually based on the first constant and the second constant determined by the determination unit and the condition of Equation 2.

5. The lighting device according to claim 3 or 4.

6. the second LED is a white LED including a red LED emitting red light, a green LED emitting green light, and a blue LED emitting blue light; The lighting device according to claim 1 .

7. The light color of the first LED and the light color of the second LED are the same type of light source color. The lighting device according to claim 1 .

8. Illuminating art works in art galleries or museums, The lighting device according to claim 1 .

9. At least two types of LEDs; a lighting device that lights up the at least two types of LEDs individually, The at least two types of LEDs are A first LED; a second LED that emits light having a color gamut area ratio higher than that of the first LED; The lighting device is The first LED and the second LED are configured to be individually dimmable according to a total luminous flux of light obtained by combining the light emitted from the first LED and the light emitted from the second LED, individually dimming the first LED and the second LED so that a proportion of the luminous flux of the first LED in the total luminous flux increases as the total luminous flux increases; Lighting equipment.

10. The lighting device according to claim 1 or claim 9; and a fixture body that houses the lighting device. Lighting fixtures.

11. The lighting device includes: A plurality of the first LEDs; a plurality of the second LEDs; The plurality of first LEDs are arranged around the optical axis of the fixture body, The plurality of second LEDs are arranged around the plurality of first LEDs.

11. A lighting fixture according to claim 10.

Images