Lighting device, lighting fixture, lighting lamp, and lighting system

Abstract

A lighting device (40) comprises multiple LED packages (42) that each generate at least two types of light having different chromaticity values. The patterns of first graphs showing the correlation between the relative total light flux and the relative electrical current of respective multiple LED packages (42) are equal over the range of electrical current that was actually supplied.

Description

Lighting devices, lighting fixtures, lighting lamps and lighting systems

[0001] The present invention relates to a lighting device, a lighting fixture, a lighting lamp, and a lighting system.

[0002] Conventionally, techniques for adjusting the chromaticity of output light from a lighting device have been proposed (see, for example, Patent Document 1).

[0003] Special Publication No. 2012-507139

[0004] However, with conventional technologies, when dimming is performed, the relative total luminous flux and relative current characteristics assumed during dimming differ from the actual relative total luminous flux and actual relative current characteristics, and these characteristics also differ among the LED (Light Emitting Diode) packages mounted on the lighting device, resulting in a problem of varying chromaticity during dimming.

[0005] Therefore, the present disclosure provides a lighting device and the like that can suppress chromaticity differences during dimming.

[0006] An illumination device according to one aspect of the present disclosure is an illumination device including a plurality of LED packages that emit two or more types of light with different chromaticity values, and each first graph shape showing the relationship between the relative total luminous flux and the relative current of each of the plurality of LED packages is equivalent within the range of current actually supplied.

[0007] An illumination device according to one aspect of the present disclosure is an illumination device including a plurality of LED packages that emit four or more types of light with different chromaticity values, wherein in a polygon on a chromaticity diagram formed by connecting the chromaticity values ​​of the four or more types of light emitted by the plurality of LED packages, the shapes of the second graphs showing the relationship between the relative total luminous flux and the relative current of each LED package located on the diagonal of the polygon are equivalent.

[0008] Furthermore, a lighting fixture according to one aspect of the present disclosure includes a lighting device and a power supply device that supplies power to each of the plurality of LED packages.

[0009] An illumination lamp according to an aspect of the present disclosure includes an illumination device.

[0010] Also, a lighting system according to one aspect of the present disclosure includes a lighting device, a power supply device that supplies power to the lighting device, a control device that controls the lighting device, and a communication device that performs communication related to the control of the lighting device.

[0011] According to the present disclosure, a lighting device and the like that can suppress chromaticity difference during dimming is provided.

[0012] FIG. 1A is a block diagram showing a lighting system according to an embodiment. FIG. 1B is a diagram showing an LED package. FIG. 2 is a diagram showing x,y chromaticity coordinates defined in JIS Z 8110-1995. FIG. 3 is a diagram showing characteristics of ideal light emitted by a conventional LED package and characteristics of light actually emitted by the conventional LED package. FIG. 4 is a diagram showing a case where a first graph shape is linear. FIG. 5 is a diagram showing a case where a first graph shape is substantially linear. FIG. 6 is a diagram showing a case where a first graph shape is curved. FIG. 7 is a diagram showing x,y chromaticity coordinates. FIG. 8 is another diagram showing x,y chromaticity coordinates. FIG. 9 is a diagram showing the spectrum of light emitted by each of six LED packages.

[0013] Hereinafter, the embodiments will be described in detail with reference to the drawings. Note that the embodiments described below are all comprehensive or specific examples. The numerical values, shapes, materials, components, component placement and connection forms, steps, and step order shown in the following embodiments are merely examples and are not intended to limit the present disclosure. Furthermore, among the components in the following embodiments, components not recited in independent claims will be described as optional components.

[0014] It should be noted that the drawings are schematic diagrams and are not necessarily strict illustrations. In addition, in the drawings, substantially the same components are denoted by the same reference numerals, and overlapping descriptions may be omitted or simplified.

[0015] (Embodiment) [Configuration] First, a lighting device 40, a lighting fixture 5, an illumination lamp, and a lighting system 1 according to an embodiment will be described with reference to FIGS. 1A and 1B.

[0016] Fig. 1A is a block diagram showing a lighting system 1 according to an embodiment, and Fig. 1B is a diagram showing an LED package.

[0017] The lighting system 1 is a system that can make the lighting device 40 emit light at a chromaticity desired by a user by independently adjusting the dimming of two or more types of LED packages 42 with different chromaticity values ​​provided in the lighting device 40. The lighting system 1 is a system that supports the chromaticity adjustment function of the lighting device 40.

[0018] The lighting system 1 includes an input device 20, a communication device 10, a control device 30, a lighting device 40, and a power supply device 50. Note that the lighting system 1 may include a plurality of lighting devices 40 for one control device 30. The communication device 10, the control device 30, the lighting device 40, and the power supply device 50 may constitute a lighting fixture 5.

[0019] Input device 20 receives input from a user regarding the control of lighting device 40. The input regarding the control of lighting device 40 is an input for specifying the chromaticity of light emitted by lighting device 40. Input device 20 transmits the received input regarding the control of lighting device 40 to communication device 10 of lighting fixture 5 as a control signal.

[0020] The input device 20 is, for example, a portable information terminal such as a smartphone or a tablet terminal, but may also be a stationary information terminal that is fixedly installed on a wall, etc. The input device 20 may be realized by installing an application program corresponding to the lighting system 1 in a general-purpose device, or may be a device dedicated to the lighting system 1.

[0021] The communication device 10 receives a control signal via wireless communication from an input device external to the lighting device 40. More specifically, the communication device 10 receives a control signal from the input device (remote controller) via an antenna. The communication device 10 may have a built-in antenna. The frequency band of the wireless communication performed by the communication device 10 is the UHF (Ultra High Frequency) band or the SHF (Super High Frequency) band, but the frequency band of the wireless communication performed by the communication device 10 may be another frequency band.

[0022] The control device 30 controls the lighting device 40 to emit light at a chromaticity input to the input device 20 (input related to the control of the lighting device 40) indicated by the control signal acquired by the communication device 10. The control device 30 includes a control unit 31 and a storage unit 32. The input device 20 and the control device 30 may be realized as a single integrated device.

[0023] The control unit 31 controls the 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 sending a control signal to the lighting device 40. The control unit 31 is realized by, for example, a microcomputer, but may also be realized by a processor. The functions of the control unit 31 are realized by the microcomputer or processor constituting the control unit 31 executing a computer program stored in the storage unit 32.

[0024] The storage unit 32 is a storage device that stores the computer program executed by the control unit 31 and various information required to control the lighting device 40. Specifically, the storage unit 32 is realized by a semiconductor memory or the like.

[0025] The lighting device 40 is installed, for example, indoors and illuminates the indoor space. The lighting device 40 may be, for example, an LED module.

[0026] As shown in FIG. 1B, the lighting device 40 includes a substrate 44 and a plurality of LED packages 42 mounted on the substrate 44 .

[0027] The substrate 44 is a mounting substrate for mounting the plurality of LED packages 42. The substrate 44 is, for example, a printed wiring board (printed circuit board) on which metal wiring is formed in a predetermined pattern. A resist made of an insulating resin material may be formed on the surface of the substrate 44 to cover the wiring and protect the wiring and ensure a dielectric strength voltage. The substrate 44 may be a single-sided wiring board in which wiring is formed only on the main surface on which the plurality of LED packages 42 are mounted, or a double-sided wiring board in which wiring is formed on both sides. The substrate 44 may also be a rigid substrate or a film-like flexible substrate.

[0028] The LED packages 42 are mounted at predetermined intervals on the main surface of the substrate 44. Note that Fig. 1B shows one LED package 42 as an example.

[0029] Specifically, the plurality of LED packages 42 emit light when a direct current is supplied from the power supply device 50 via an electric wire connecting the power supply device 50 and the substrate 44 .

[0030] Each of the plurality of LED packages 42 is an individually packaged surface mount device (SMD) structure or chip on board (COB) structure.

[0031] Each of the LED packages 42 includes a white resin or ceramic container (package), an LED element 42 a (bare chip) disposed in the container, and a sealing member 42 b that seals the LED element 42 a. The sealing member 42 b contains a phosphor 42 c.

[0032] Furthermore, the lighting device 40 may be a ceiling light having multiple LED packages 42, a spotlight having multiple LED packages 42, a downlight having multiple LED packages 42, or an illumination lamp (light bulb) having multiple LED packages 42.

[0033] The lighting device 40 includes a dimming circuit 41 in addition to a plurality of LED packages 42 .

[0034] The dimming circuit 41 is a circuit that supplies current (power) to the multiple LED packages 42 in response 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 multiple LED packages 42 by switching a switching element included in the dimming circuit 41 (chopper control circuit) using the control signal. The dimming circuit 41 can supply current to each of the multiple LED packages 42 independently. In other words, the dimming circuit 41 can independently dim the multiple LED packages 42.

[0035] The plurality of LED packages 42 are at least two of a purple light source, a blue-violet light source, a blue light source, a blue-green light source, a green light source, a yellow-green light source, a yellow light source, a yellow-red light source, a red light source, and a red-violet light source.

[0036] The purple light source is a light source that emits purple light. The purple light source emits purple light having an emission peak wavelength of, for example, 380 nm or more and 430 nm or less (specifically, including at least purple light and may further include blue light). Specifically, the purple light source is a light-emitting module using a purple LED, but the specific form of the purple light source is not particularly limited.

[0037] The blue-violet light source is a light source that emits blue-violet light. The blue-violet light source emits, for example, blue-violet light having an emission peak wavelength of 400 nm or more and 450 nm or less (more specifically, including blue-violet light, and may further include at least one of blue light and purple light). The blue-violet light source is specifically a light-emitting module that uses a blue-violet LED, but the specific form of the blue-violet light source is not particularly limited.

[0038] The blue light source is a light source that emits blue light. The blue light source emits blue light (specifically, at least blue light and may further include violet light) with an emission peak wavelength of about 380 nm or more and about 480 nm or less. Specifically, the blue light source is a light-emitting module using a blue LED, but the specific form of the blue light source is not particularly limited.

[0039] The blue-green light source is a light source that emits blue-green light (blue-green is sometimes expressed as emerald green, etc.). The blue-green light source emits, for example, blue-green light having an emission peak wavelength of about 465 nm or more and about 490 nm or less (more specifically, it includes blue-green light, and may further include at least one of blue light and green light). The blue-green light source is specifically a light-emitting module that uses a blue-green LED, but the specific form of the blue-green light source is not particularly limited.

[0040] The green light source is a light source that emits green light. The green light source emits, for example, green light having an emission peak wavelength of about 480 nm or more and about 580 nm or less (specifically, it includes at least green light, and may further include at least one of green-blue light, blue-green light, and yellow-green light). The green light source is specifically a light-emitting module using a green LED, but the specific form of the green light source is not particularly limited.

[0041] The yellow-green light source is a light source that emits yellow-green light. The yellow-green light source emits, for example, yellow-green light having an emission peak wavelength of about 560 nm or more and about 580 nm or less (specifically, it includes at least yellow-green light, and may further include at least one of yellow light and green light). The yellow-green light source is specifically a light-emitting module using a yellow-green LED, but the specific form of the yellow-green light source is not particularly limited.

[0042] The yellow light source is a light source that emits yellow light. The yellow light source emits, for example, yellow light having an emission peak wavelength of about 580 nm or more and about 595 nm or less (specifically, it includes at least yellow light, and may further include at least one of yellow-green light and yellow-red light). Specifically, the yellow light source is a light-emitting module using a yellow LED, but the specific form of the yellow light source is not particularly limited.

[0043] The yellow-red light source is a light source that emits yellow-red light. The yellow-red light source emits, for example, yellow-red light having an emission peak wavelength of about 595 nm or more and about 610 nm or less (specifically, it includes at least yellow-red light, and may further include at least one of yellow light and red light). The yellow-red light source is specifically a light-emitting module using a yellow-red LED, but the specific form of the yellow-red light source is not particularly limited.

[0044] The red light source is a light source that emits red light. The red light source emits red light (specifically, at least red light and may further include yellow light) with an emission peak wavelength of about 610 nm or more and about 750 nm or less. Specifically, the red light source is a light-emitting module using a red LED, but the specific form of the red light source is not particularly limited.

[0045] The red-violet light source is a light source that emits red-violet light. The red-violet light source emits red-violet light having an emission peak wavelength of, for example, about 750 nm or more and about 830 nm or less (specifically, at least red-violet light is included, and may further include red light). The red-violet light source is specifically a light-emitting module using a red-violet LED, but the specific form of the red-violet light source is not particularly limited.

[0046] Here, the green light emitted by the green light source, the red light emitted by the red light source, and the yellow light emitted by the yellow light source may be realized by fluorescence emitted by the phosphor 42c. In this case, each of the green light source, the red light source, and the yellow light source includes an excitation light source realized by, for example, a blue LED or the like, and a phosphor-containing resin that seals the excitation light source. The phosphor 42c constituting the green light source is Y ３ (Al, Ga) ５ O １２ : Ce phosphor or other yttrium aluminum garnet (YAG) green phosphors, but Lu ３ Al ５ O １２ The phosphor 42c constituting the red light source may be a green phosphor of the lutetium aluminum garnet (LuAG) system, such as a CaAlSiN phosphor. ３ : Eu phosphor or (Sr,Ca)AlSiN３ The phosphor 42c constituting the yellow light source is a red phosphor such as Eu phosphor. ３ (Al, Ga) ５ O １２ : Ce phosphors and other yttrium aluminum garnet (YAG)-based yellow phosphors, but Lu ３ Al ５ O １２ The phosphor may be a lutetium aluminum garnet (LuAG)-based yellow phosphor, such as a :Ce phosphor.

[0047] Furthermore, the purple light source, blue-violet light source, blue-green light source, yellow-green light source, yellow-red light source, and red-violet light source may be realized by combining these light sources, combining LED elements 42a that emit blue light, green light, and red light, or selectively combining among them.

[0048] The power supply device 50 supplies power (current) to the plurality of LED packages 42 to cause the plurality of LED packages 42 to emit light based on a control signal output from the control device 30. The power supply device 50 converts AC power to DC power, and then converts the converted DC power into DC power suitable for driving the control device 30 and the lighting circuit, and outputs the converted DC power. More specifically, the power supply device 50 is configured, for example, with a lighting circuit, a diode bridge rectifier circuit that converts AC power to DC power, and a DC-DC converter IC. Note that the power supply device 50 may also be realized by a single IC having equivalent functions to the rectifier circuit and the DC-DC converter. The lighting circuit is, specifically, an LED driver IC.

[0049] The power supply device 50 is a component of the lighting fixture 5 and the lighting system 1, but is not a component of the lighting lamp.

[0050] [Chromaticity] First, the chromaticity of the light emitted from each of the plurality of LED packages 42 will be described with reference to FIG.

[0051] 2 is a diagram showing x, y chromaticity coordinates defined in JIS Z 8110-1995. The chromaticity coordinates in FIG. 2 show the color space defined in CIE1931.

[0052] In this lighting system 1, the chromaticity of the light emitted by the lighting device 40 can be adjusted by selectively activating at least two of the purple light source, blue-violet light source, blue light source, blue-green light source, green light source, yellow-green light source, yellow light source, yellow-red light source, red light source, and red-violet light source contained in the multiple LED packages 42.

[0053] The light emitted by lighting device 40 refers to output light that is a combination of at least two of the following: purple light emitted from a purple light source, blue-purple light emitted from a blue-purple light source, blue light emitted from a blue-green light source, blue light emitted from a blue-green light source, green light emitted from a green light source, yellow-green light emitted from a yellow-green light source, yellow light emitted from a yellow light source, yellow-red light emitted from a yellow-red light source, red light emitted from a red light source, and red-purple light emitted from a red-purple light source, and refers to the output light that is finally emitted from lighting device 40.

[0054] The chromaticity values ​​of the light emitted by each of the plurality of LED packages 42 are the coordinate values ​​of at least two of the dotted hatched areas of purple, blue-purple, blue, blue-green, green, yellow-green, yellow, yellow-red, red, and red-purple shown in the x, y chromaticity coordinates defined in JIS Z 8110-1995 shown in FIG. 2 .

[0055] For example, if the colors of light emitted by the six LED packages 42 are blue-violet, blue, blue-green, green, yellow, and red, as shown in the x, y chromaticity coordinates of Fig. 2, the control device 30 individually controls the currents applied to these six LED packages 42. In this case, the total luminous flux output of the six LED packages 42 can be adjusted, thereby reproducing a predetermined chromaticity.

[0056] Next, a case where there are individual differences among the plurality of LED packages will be described.

[0057] If there are individual differences among the multiple LED packages, the total luminous flux and chromaticity of the light emitted by each of the multiple LED packages may differ. For example, there are individual differences between a first lighting device consisting of six LED packages and a second lighting device consisting of another six LED packages.

[0058] For this reason, in this embodiment, the control device 30 separately controls the current applied to the first lighting device, which is an example of the lighting device 40, and the current applied to the second lighting device, which is another example of the lighting device 40.

[0059] For example, in the first lighting device, the control device 30 individually controls the applied current to the blue-violet light source to be 98 mA, the applied current to the blue light source to be 150 mA, the applied current to the blue-green light source to be 197 mA, the applied current to the green light source to be 302 mA, the applied current to the yellow light source to be 210 mA, and the applied current to the red light source to be 165 mA.

[0060] In addition, in the second lighting device, the control device 30 individually controls the applied current to the blue-violet light source to be 92 mA, the applied current to the blue light source to be 172 mA, the applied current to the blue-green light source to be 250 mA, the applied current to the green light source to be 401 mA, the applied current to the yellow light source to be 150 mA, and the applied current to the red light source to be 221 mA.

[0061] As a result, the total luminous flux and chromaticity when the first lighting device emits light are equivalent to the total luminous flux and chromaticity when the second lighting device emits light.

[0062] Next, with reference to FIG. 3, a case where the characteristics of the ideal light emitted by the LED package differ from the characteristics of the light actually emitted by the LED package will be described.

[0063] 3 is a diagram showing the ideal light characteristics of a conventional LED package and the actual light characteristics of the conventional LED package. The ideal light characteristics are assumed for correction during dimming.

[0064] Figure 3(a) shows the relationship between forward current and relative total luminous flux, which indicates the characteristics of light emitted by a conventional LED package. Figure 3(b1) shows the relationship between forward current and relative total luminous flux, which indicates the characteristics of light emitted by a conventional LED package when a current of 500 mA is applied. Figure 3(b2) shows the relationship between forward current and relative total luminous flux, which indicates the characteristics of light emitted by a conventional LED package when a current of 300 mA is applied. Figure 3(c1) shows the relationship between relative forward current and relative total luminous flux, which indicates the characteristics of light emitted by a conventional LED package when a current of 500 mA is applied. Figure 3(c2) shows the relationship between relative forward current and relative total luminous flux, which indicates the characteristics of light emitted by a conventional LED package when a current of 300 mA is applied.

[0065] For example, as shown in (b1) and (b2) of Figure 3, when an LED package has a nonlinear characteristic in the relationship between the relative total luminous flux and the forward current, there is a difference in the relative total luminous flux between the ideal graph shape shown by the dashed line and the first graph shape shown by the solid line in the actual current range, both when a current of 500 mA is applied and when a current of 300 mA is applied. In particular, the difference in relative total luminous flux becomes larger as the applied current increases.

[0066] As an example, assume that the forward current of the first red light source is 500 mA when it is turned on at a dimming rate of 100%, and the forward current of the second red light source is 300 mA when it is turned on at a dimming rate of 100%.

[0067] In this case, even if the chromaticity is the same, the difference in the relative total luminous flux of the light emitted by the first red light source is greater than the difference in the relative total luminous flux of the light emitted by the second red light source, resulting in a difference in the total luminous flux of the light emitted by the first red light source and the second red light source. As a result, the chromaticity differs between the first lighting device having the first red light source and the second lighting device having the second red light source. In particular, when the first lighting device and the second lighting device are arranged closely to each other, or when the first red light source and the second red light source are arranged closely to each other, the difference in chromaticity may cause discomfort to people.

[0068] Therefore, in the present embodiment, in a lighting device 40 including a plurality of LED packages 42 emitting two or more types of light with different chromaticity values, the first graph shapes showing the relationship between the relative total luminous flux and the relative current of each of the plurality of LED packages 42 may be equivalent within the range of the current actually supplied. "Equal" includes cases where the graphs are completely identical or substantially identical, and may have an error of a few percent, e.g., ±5%. In the present embodiment, the relative total luminous flux refers to the total luminous flux of a certain LED package 42 or a relative total luminous flux based on a preset reference total luminous flux.

[0069] In this case, each first graph shape may be linear. Here, "linear" means a straight line, but is not limited to a perfect straight line, and may be recognized as a substantially straight line, and may have an error of about a few percent, for example, ±5%.

[0070] In this embodiment, the light emitted by each of the plurality of LED packages 42 may be realized by a composite light of the light emitted by the LED element 42 a and the fluorescence emitted by the phosphor 42 c. In this case, it is expected that the first graph shapes of the respective LED packages 42 will be equivalent.

[0071] Furthermore, if the semiconductor material configuration of the LED elements 42a constituting each of the plurality of LED packages 42 is the same, it can be expected that the first graph shapes of each of the plurality of LED packages 42 will be equivalent.

[0072] 4 and 5 , a case will be described in which the control device 30 controls the reference current applied to the plurality of LED packages 42 to match the chromaticity of the light emitted by the plurality of LED packages 42 to a predetermined reference chromaticity, thereby matching the chromaticity of the light emitted by each of the plurality of LED packages 42. Matching to a predetermined reference chromaticity means matching each first graph shape to an ideal graph shape and / or matching each first graph shape using one of the first graph shapes as a reference.

[0073] FIG. 4 illustrates a case where the first graph shape is linear. FIG. 5 illustrates a case where the first graph shape is substantially linear. In FIG. 5, the current value in each first graph shape is linear from zero to a predetermined value. If the current value exceeds the predetermined value, the LED package 42 may be used only at a current value below the predetermined value for each first graph shape that has a non-linear characteristic. As long as the LED package 42 is used in a region with a linear characteristic, the chromaticity difference is unlikely to become large. The predetermined value is, for example, when the LED package 42 is fully lit (dimming rate 100%).

[0074] 4 and 5 illustrate four LED packages 42 with different chromaticity values, and illustrate an LED package 42 emitting green light (green light source) and an LED package 42 emitting red light (red light source). (a1) of FIG. 4 and (a1) of FIG. 5 show the relationship between the relative total luminous flux and current (e.g., forward current) for the green light source, while (a2) of FIG. 4 and (a2) of FIG. 5 show the relationship between the relative total luminous flux and current (e.g., relative forward current) for the green light source. The relative current is the current with 500 mA applied to the green light source as a reference current of 1.0. (b1) of FIG. 4 and (b1) of FIG. 5 show the relationship between the relative total luminous flux and current (e.g., forward current) for the red light source, while (b2) of FIG. 4 and (b2) of FIG. 5 show the relationship between the relative total luminous flux and current for the red light source. The relative current is the current with 300 mA applied to the red light source as a reference current of 1.0. The actual current range is from 0 to 1.0 relative current.

[0075] As a result, the first graph shape of each of the plurality of LED packages 42 becomes an ideal linear graph shape.

[0076] (c1) and (c2) in Fig. 4 show the results of comparing (a2) in Fig. 4 for a green light source with (b2) in Fig. 4 for a red light source, and (c1) and (c2) in Fig. 5 show the results of comparing (a2) in Fig. 5 for a green light source with (b2) in Fig. 5 for a red light source.

[0077] In (c1) and (c2) of Figure 4 and (c1) and (c2) of Figure 5, the graph shapes of the green light source and the red light source are consistent. In particular, the graph shapes of the relative currents used during actual dimming of the green light source, from 0 to 1.0, are consistent with the graph shapes of the relative currents used during actual dimming of the red light source, from 0 to 1.0. According to (c1) and (c2) of Figure 4 and (c1) and (c2) of Figure 5, the total luminous flux fluctuates at the same rate depending on the dimming ratio (current ratio) of the green light source and the dimming ratio (current ratio) of the red light source. Therefore, even when the green light source and the red light source are dimmed, i.e., when each of the multiple LED packages 42 is dimmed, chromaticity differences are unlikely to occur among the multiple LED packages 42. This reduces chromaticity differences in the light emitted by each of the multiple LED packages 42.

[0078] 4 and 5 have been described with respect to the LED package 42 that emits green light and the LED package 42 that emits red light, the same applies to the LED packages 42 that emit light of other colors. Note that even if multiple LED packages 42 emit light of the same color, individual differences may exist among the LED packages 42. In this case, the reference current may be adjusted to match the chromaticity of the light emitted by the LED packages 42 to a preset reference chromaticity.

[0079] Each first graph shape may be an upwardly convex curve. Here, a curve means a continuously curved line, but may also include a broken line.

[0080] In this embodiment, the light emitted by each of the plurality of LED packages 42 may be realized by a composite light of the light emitted by the LED element 42 a and the fluorescence emitted by the phosphor 42 c. In this case, it is expected that the first graph shapes of the respective LED packages 42 will be equivalent.

[0081] When a plurality of LED packages 42 emitting two or more types of light with different chromaticity values ​​are used, the first graph shapes are different from each other. In this case, it is unlikely that all of the first graph shapes for the plurality of LED packages 42 will be linear.

[0082] Furthermore, if the semiconductor material configurations of the LED elements 42 a constituting each of the multiple LED packages 42 are different, the recombination frequency within each semiconductor material will be different. In this case, it is unlikely that all of the first graph shapes for the multiple LED packages 42 will be linear.

[0083] The LED package 42 having the most different first graph shape among the first graph shapes of the plurality of LED packages 42 may be arranged in the center of the area where the plurality of LED packages 42 are mounted on the substrate of the lighting device 40. The most different first graph shape is the graph shape with the greatest change. The temperature tends to rise easily in the center of the area where the plurality of LED packages 42 are mounted. Therefore, the total luminous flux of the LED package 42 arranged in the center of the area is likely to decrease, and it is expected that the first graph shape will approach linearity.

[0084] To make the first graph shape linear or curved, this may be achieved by selecting LED elements 42a such that the first graph shape of the total luminous flux of the LED package 42 is linear or curved. Alternatively, since the first graph shape is likely to be linear in the low current region where the applied current is lower than a predetermined value, this may be achieved by having the control device 30 control the current applied to the LED package 42.

[0085] Next, referring to Figure 6, we will explain the case where the control device 30 controls the reference current applied to the multiple LED packages 42 to match the chromaticity of the light emitted by the multiple LED packages 42 to a predetermined reference chromaticity, thereby matching the chromaticity of the light emitted by each of the multiple LED packages 42.

[0086] FIG. 6 illustrates four LED packages 42 with different chromaticity values, showing an LED package 42 emitting green light (green light source) and an LED package 42 emitting red light (red light source). (a1) of FIG. 6 shows the relationship between the relative total luminous flux and current (e.g., forward current) for the green light source, and (a2) of FIG. 6 shows the relationship between the relative total luminous flux and relative current (e.g., relative forward current) for the green light source. The relative current is a current where 500 mA applied to the green light source is set as a reference current of 1.0. (b1) of FIG. 6 shows the relationship between the relative total luminous flux and current for the red light source, and (b2) of FIG. 6 shows the relationship between the relative total luminous flux and current for the red light source. The relative current is a current where 300 mA applied to the red light source is set as a reference current of 1.0. The actual current range is a relative current of 0 to 1.0.

[0087] As a result, the first graph shape of each of the plurality of LED packages 42 becomes an ideal linear graph shape.

[0088] (c1) and (c2) of FIG. 6 show the results of comparing (a2) of FIG. 6 using a green light source with (b2) of FIG. 6 using a red light source.

[0089] In (c1) and (c2) of Figure 6, the graph shapes of the green light source and the red light source are substantially identical except for relative currents of 1.5 or greater. In particular, the graph shapes of the green light source from 0 to 1.0, which are used for actual dimming, are identical to the graph shapes of the red light source from 0 to 1.0, which are used for actual dimming. In (c1) and (c2) of Figure 6, the total luminous flux fluctuates at the same rate depending on the dimming ratio (current ratio) of the green light source and the dimming ratio (current ratio) of the red light source. Therefore, even when the green light source and the red light source are dimmed, i.e., when each of the multiple LED packages 42 is dimmed, chromaticity differences are unlikely to occur among the multiple LED packages 42. This reduces chromaticity differences in the light emitted by each of the multiple LED packages 42.

[0090] 6 has been described with respect to the LED package 42 that emits green light and the LED package 42 that emits red light, but the same applies to the LED packages 42 that emit light of other colors. Note that even if multiple LED packages 42 emit light of the same color, individual differences may exist among the LED packages 42. In this case, the reference current may be adjusted to match the chromaticity of the light emitted by the LED packages 42 to a preset reference chromaticity.

[0091] As another example, in the present embodiment, in a lighting device 40 including a plurality of LED packages 42 that emit four or more types of light with different chromaticity values, a polygon (FIGS. 7 and 8, described later) on the CIE x,y chromaticity coordinate system may be formed by connecting the chromaticity values ​​of the four or more types of light emitted by the plurality of LED packages 42, and the shapes of the second graphs showing the relationship between the relative total luminous flux and the relative current of each of the LED packages 42 located on the diagonal line of the polygon may be equivalent. Here, equivalent includes cases where the graphs are completely identical and cases where they are substantially identical, and may have an error of a few percent, for example, ±5%.

[0092] In this case, each second graph shape may be linear. Here, "linear" means a straight line, but is not limited to a perfect straight line, and may be recognized as a substantially straight line, and may have an error of a few percent, for example, ±5%. When each second graph shape is linear, the same process applies as when each first graph shape is linear, and therefore detailed description thereof will be omitted.

[0093] Furthermore, each second graph shape may be a curved line that is convex upward. Here, a curved line refers to a continuously curved line, but may also include a broken line. When each second graph shape is a curved line, the same applies as when each first graph shape is a curved line, and therefore detailed description thereof will be omitted.

[0094] In this embodiment, the light emitted by each of the plurality of LED packages 42 may be realized by combining the light emitted by the LED element 42 a and the fluorescence emitted by the phosphor 42 c. In this case, it is expected that the second graph shapes of the respective LED packages 42 will be equivalent.

[0095] Here, polygons on the CIE x, y chromaticity coordinate system will be described with reference to FIGS.

[0096] Figure 7 is a diagram showing x,y chromaticity coordinates, and Figure 8 is another diagram showing x,y chromaticity coordinates.

[0097] For example, Fig. 7 shows a polygon on the CIE x,y chromaticity coordinate system formed by connecting the chromaticity values ​​of four types of light emitted by four LED packages 42. Fig. 8 shows a polygon on the CIE x,y chromaticity coordinate system formed by connecting the chromaticity values ​​of six types of light emitted by six LED packages 42.

[0098] 7 , the four types of light emitted by the four LED packages 42 are blue-violet light emitted by the blue-violet light source, green light emitted by the green light source, yellow-red light emitted by the yellow-red light source, and red light emitted by the red light source. The chromaticity coordinates of each color are (0.157, 0.021) for the blue-violet light, (0.168, 0.729) for the green light, (0.568, 0.422) for the yellow-red light, and (0.695, 0.305) for the red light. The polygon formed using these chromaticity coordinates includes a diagonal line connecting the chromaticity coordinates of blue-violet light (0.157, 0.021) and the chromaticity coordinates of yellow-red light (0.568, 0.422), and a diagonal line connecting the chromaticity coordinates of green light (0.168, 0.729) and the chromaticity coordinates of red light (0.695, 0.305).

[0099] In this case, since each second graph shape located on the diagonal line is set to be equal, the second graph shape of the blue-violet light source and the second graph shape of the yellow-red light source are equal, and the second graph shape of the green light source and the second graph shape of the red light source are equal.

[0100] 8 , the six types of light emitted by the six LED packages 42 are blue-violet light emitted by the blue-violet light source, blue light emitted by the blue light source, blue-green light emitted by the blue-green light source, green light emitted by the green light source, yellow-red light emitted by the yellow-red light source, and red light emitted by the red light source. The chromaticity coordinates of each color are (0.157, 0.021) for the blue light, (0.126, 0.078) for the blue light, (0.095, 0.365) for the blue-green light, (0.168, 0.729) for the green light, (0.568, 0.422) for the yellow-red light, and (0.695, 0.305) for the red light.

[0101] The polygon formed using these chromaticity coordinates includes a diagonal line connecting the chromaticity coordinates (0.157, 0.021) of blue-violet light and the chromaticity coordinates (0.095, 0.365) of blue-green light, a diagonal line connecting the chromaticity coordinates (0.157, 0.021) of blue-violet light and the chromaticity coordinates (0.168, 0.729) of green light, a diagonal line connecting the chromaticity coordinates (0.157, 0.021) of blue-violet light and the chromaticity coordinates (0.568, 0.422) of yellow-red light, a diagonal line connecting the chromaticity coordinates (0.126, 0.078) of blue light and the chromaticity coordinates (0.168, 0.729) of green light, and a diagonal line connecting the chromaticity coordinates (0.126, 0.078) of blue light and the chromaticity coordinates (0.126, 0.078) of green light. a diagonal line connecting the chromaticity coordinates (0.78) of blue light and the chromaticity coordinates (0.695, 0.305) of red light; a diagonal line connecting the chromaticity coordinates (0.095, 0.365) of blue-green light and the chromaticity coordinates (0.568, 0.422) of yellow-red light; a diagonal line connecting the chromaticity coordinates (0.095, 0.365) of blue-green light and the chromaticity coordinates (0.695, 0.305) of yellow-red light; a diagonal line connecting the chromaticity coordinates (0.095, 0.365) of blue-green light and the chromaticity coordinates (0.695, 0.305) of red light; and a diagonal line connecting the chromaticity coordinates (0.168, 0.729) of green light and the chromaticity coordinates (0.695, 0.305) of red light.

[0102] In this case, since each second graph shape located on the diagonal line is set to be equal, the second graph shape of the blue-violet light source, the second graph shape of the blue light source, the second graph shape of the blue-green light source, the second graph shape of the green light source, the second graph shape of the yellow-red light source, and the second graph shape of the red light source are equal.

[0103] Although four LED packages 42 and six LED packages 42 are exemplified, five LED packages 42 or seven or more LED packages 42 may also be used.

[0104] Furthermore, as another example, in this embodiment, the first graph shape showing the relationship between the relative total luminous flux and the relative current of the first LED package (LED package 42) having the highest relative luminous efficiency corresponding to the peak wavelength in the spectrum of light emitted from the first LED package 42 may be equivalent to the first graph shape showing the relationship between the relative total luminous flux and the relative current of a second LED package (LED package 42) other than the first LED package.

[0105] In other words, among the first graph shapes, the first graph shape of the first LED package having the highest relative luminous efficiency corresponding to the peak wavelength may be used as a reference, and the remaining second LED packages may be adjusted to match the first graph shape using the first graph shapes of the remaining second LED packages as a reference.

[0106] Here, an example of adjusting the LED package 42 will be described with reference to FIG.

[0107] 9 is a diagram showing the spectrum of light emitted by each of the six LED packages 42. In FIG. 9, the relationship between the relative intensity and the wavelength of the light emitted by each of the six LED packages 42 is shown.

[0108] For example, if the colors of light emitted by each of the six LED packages 42 are blue-violet, blue, blue-green, green, yellow, and red, the peak wavelength of green light has the highest relative luminous efficiency (sensitivity at 555 nm), so the first graph shape of the LED module emitting green light can be used as a reference and each of the LED modules emitting light of the other five colors can be adjusted.

[0109] At this time, the control device 30 may control the current applied to the remaining LED packages 42 so that the first graph shape of the remaining LED packages 42 matches the first graph shape of the LED package 42 with the highest relative luminous efficiency corresponding to the peak wavelength.

[0110] As described above, the light emitted by one or more of the multiple LED packages 42 may be realized by combining light emitted by the LED element 42 a and fluorescence emitted by the phosphor 42 c. Alternatively, the LED package 42 may include only the LED element 42 a. That is, the light emitted by the multiple LED packages 42 may be composed of direct light emitted by the LED element 42 a and a combined light of the light emitted by the LED element 42 a and fluorescence emitted by the phosphor 42 c. For example, as shown in FIG. 9 , the blue-violet light emitted by the blue-violet light source, the blue light emitted by the blue-green light source, the green light emitted by the green light source, and the red light emitted by the red light source may be direct light emitted by the LED element 42 a, and the yellow light emitted by the yellow light source may be a combined light of the blue light of the LED element 42 a (e.g., a blue LED element) and fluorescence emitted by the phosphor 42 c.

[0111] In this case, the light emitted from each of the multiple LED packages 42 has a broad emission spectrum. Therefore, even in a region with a steep slope such as the high region described above, fluctuations in the total luminous flux are suppressed, and chromaticity differences can be suppressed during dimming.

[0112] [Effects, etc.] Next, effects, etc. of the lighting device 40, the lighting fixture 5, the lighting lamp, and the lighting system 1 according to the embodiment will be described.

[0113] As described above, the lighting device 40 of Technology 1 according to this embodiment is a lighting device 40 including a plurality of LED packages 42 that emit two or more types of light with different chromaticity values, and each of the first graph shapes showing the relationship between the relative total luminous flux and the relative current of each of the plurality of LED packages 42 is equivalent within the range of current actually supplied.

[0114] According to this, the first graph shapes of the plurality of LED packages 42 can be made equivalent, and therefore the relative total luminous flux of each of the plurality of LED packages 42 can be made equivalent.

[0115] Therefore, according to this lighting device 40, it is possible to suppress the chromaticity difference during dimming.

[0116] Furthermore, the lighting device 40 of Technique 2 according to this embodiment is the lighting device 40 described in Technique 1. In this case, each first graph shape is linear.

[0117] According to this, the total luminous flux fluctuates at the same rate according to the dimming ratio (current ratio) of each of the plurality of LED packages 42, so even if each of the plurality of LED packages 42 is dimmed, chromaticity differences are unlikely to occur among the plurality of LED packages 42. This makes it possible to suppress chromaticity differences in the light emitted by each of the plurality of LED packages 42.

[0118] Furthermore, the lighting device 40 of Technique 3 according to this embodiment is the lighting device 40 described in Technique 1. In this case, each first graph shape is an upwardly convex curve.

[0119] According to this, the total luminous flux fluctuates in the same manner according to the dimming ratio (current ratio) of each of the plurality of LED packages 42, so even if each of the plurality of LED packages 42 is dimmed, chromaticity differences are unlikely to occur among the plurality of LED packages 42. This makes it possible to suppress chromaticity differences in the light emitted by each of the plurality of LED packages 42.

[0120] Furthermore, in the lighting device 40 of Technology 4 relating to this embodiment, the lighting device 40 is provided with a plurality of LED packages 42 that emit four or more types of light with different chromaticity values, and in a polygon on a chromaticity diagram formed by connecting the chromaticity values ​​of the four or more types of light emitted by the plurality of LED packages 42, the shapes of the second graphs showing the relationship between the relative total luminous flux and the relative current of each LED package 42 located on the diagonal of the polygon are equivalent.

[0121] This allows the second graph shapes of the diagonally positioned LED packages 42 to be made equal, and therefore it is expected that the relative total luminous flux of each of the plurality of LED packages 42 can be made equal.

[0122] Therefore, according to this lighting device 40, it is possible to suppress the chromaticity difference during dimming.

[0123] Furthermore, the lighting device 40 of Technique 5 according to the present embodiment is the lighting device 40 described in Technique 4. In this case, each second graph shape is linear.

[0124] According to this, the total luminous flux fluctuates at the same rate according to the dimming ratio (current ratio) of each of the plurality of LED packages 42, so even if each of the plurality of LED packages 42 is dimmed, chromaticity differences are unlikely to occur among the plurality of LED packages 42. This makes it possible to suppress chromaticity differences in the light emitted by each of the plurality of LED packages 42.

[0125] The lighting device 40 according to the sixth aspect of the present embodiment is the lighting device 40 according to the fourth aspect. In this case, each second graph shape is an upwardly convex curve.

[0126] According to this, the total luminous flux fluctuates in the same manner according to the dimming ratio (current ratio) of each of the plurality of LED packages 42, so even if each of the plurality of LED packages 42 is dimmed, chromaticity differences are unlikely to occur among the plurality of LED packages 42. This makes it possible to suppress chromaticity differences in the light emitted by each of the plurality of LED packages 42.

[0127] Furthermore, the lighting device 40 of Technology 7 according to this embodiment is the lighting device 40 described in any one of Technologies 1 to 6. In this case, the shape of a first graph showing the relationship between the relative total luminous flux and the relative current in a first LED package having the highest relative luminous efficiency corresponding to the peak wavelength in the spectrum of light emitted from the first LED package among the plurality of LED packages 42 is equivalent to the shape of a first graph showing the relationship between the relative total luminous flux and the relative current in a second LED package other than the first LED package.

[0128] According to this, the first graph shape of the LED package 42 having the highest relative luminous efficiency corresponding to the peak wavelength among the respective first graph shapes is used as a reference, and the remaining LED packages 42 can be adjusted to match the first graph shape using the first graph shapes of the remaining LED packages 42 as a reference. This makes it possible to suppress chromaticity differences in the light emitted by each of the plurality of LED packages 42.

[0129] Furthermore, the lighting fixture 5 of Technique 8 according to this embodiment includes the lighting device 40 of any one of Techniques 1 to 7, and a power supply device 50 that supplies power to each of the plurality of LED packages 42.

[0130] This lighting fixture 5 also provides the same effects as those described above.

[0131] The illumination lamp of the ninth aspect of the present embodiment includes the illumination device 40 of any one of the first to seventh aspects.

[0132] This illumination lamp also provides the same effects as those described above.

[0133] Furthermore, the lighting system 1 of technique 10 according to this embodiment includes a lighting device 40 according to any one of techniques 1 to 7, a power supply device 50 that supplies power to the lighting device 40, a control device 30 that controls the lighting device 40, and a communication device 10 that communicates regarding the control of the lighting device 40.

[0134] This lighting system 1 also provides the same effects as those described above.

[0135] (Other Embodiments) Although the embodiments have been described above, the present disclosure is not limited to the above-described embodiments.

[0136] For example, in the above-described embodiments, the lighting system is realized by a plurality of devices, but 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-described embodiments. When the lighting system is realized by a plurality of devices, the components of the lighting system described in the above-described embodiments may be distributed among the plurality of devices in any manner.

[0137] In the above-described embodiment, the processing performed by a specific processing unit may be performed by another processing unit. The order of multiple processing operations may be changed, or multiple processing operations may be performed in parallel.

[0138] In the above-described embodiments, each component may be realized by executing a software program suitable for that component, or by a program execution unit such as a CPU or processor reading and executing a software program recorded on a recording medium such as a hard disk or semiconductor memory.

[0139] Furthermore, each component may be realized by hardware. Each component may be a circuit (or integrated circuit). These circuits may form a single circuit as a whole, or each may be a separate circuit. Furthermore, each of these circuits may be a general-purpose circuit or a dedicated circuit.

[0140] Furthermore, the general or specific aspects of the present disclosure may be realized as a system, an apparatus, a method, an integrated circuit, a computer program, or a computer-readable recording medium such as a CD-ROM, or as any combination of a system, an apparatus, a method, an integrated circuit, a computer program, and a recording medium.

[0141] For example, the present disclosure may be realized as a lighting method executed by a computer such as a lighting system, as a program for causing a computer to execute the lighting method, or as a computer-readable non-transitory recording medium on which such a program is recorded.

[0142] In addition, this disclosure also includes forms obtained by applying various modifications to each embodiment that a person skilled in the art would think of, or forms realized by arbitrarily combining the components and functions of each embodiment within the scope that does not deviate from the intent of this disclosure.

[0143] REFERENCE SIGNS LIST 1 Lighting system 10 Communication device 30 Control device 40 Lighting device 42 LED package (first LED package, second LED package) 50 Power supply device

Claims

1. A lighting device comprising a plurality of LED (Light Emitting Diode) packages that emit two or more types of light with different chromaticity values, wherein each first graph shape showing the relationship between the relative total luminous flux and the relative current of each of the plurality of LED packages is equivalent within the range of current actually supplied.

2. The lighting device according to claim 1, wherein each of the first graph shapes is linear.

3. The lighting device according to claim 1, wherein each of the first graph shapes is an upwardly convex curve.

4. A lighting device equipped with a plurality of LED packages that emit four or more types of light with different chromaticity values, wherein in a polygon on a chromaticity diagram formed by connecting the chromaticity values ​​of the four or more types of light emitted by the plurality of LED packages, the shapes of the second graphs showing the relationship between the relative total luminous flux and the relative current of each of the LED packages located on the diagonal of the polygon are equivalent.

5. The lighting device according to claim 4, wherein each of the second graph shapes is linear.

6. The lighting device according to claim 4, wherein each of the second graph shapes is an upwardly convex curve.

7. A lighting device as claimed in any one of claims 1 to 6, wherein a first graph shape showing the relationship between relative total luminous flux and relative current in a first LED package having the highest relative luminous efficiency corresponding to the peak wavelength in the spectrum of light emitted from the first LED package among the plurality of LED packages is equivalent to a first graph shape showing the relationship between relative total luminous flux and relative current in a second LED package other than the first LED package.

8. A lighting fixture comprising: the lighting device according to any one of claims 1 to 6; and a power supply device that supplies power to each of the plurality of LED packages.

9. An illumination lamp comprising the illumination device according to any one of claims 1 to 6.

10. A lighting system comprising: a lighting device according to any one of claims 1 to 6; a power supply device that supplies power to said lighting device; a control device that controls said lighting device; and a communication device that performs communication related to the control of said lighting device.

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