Lighting systems, lighting methods, and programs

Abstract

An object of the present disclosure is to reduce the discomfort when changing the light color. 【Solution means】When the adjustment unit 3 transitions the chromaticity coordinates of the illumination light from the first chromaticity coordinates to the second chromaticity coordinates, it calculates the luminous flux φ that satisfies the following formula 1, and calculates the luminous flux of each of the five types of LEDs based on the calculated luminous flux φ, and controls the power supply unit 2. The first chromaticity coordinates exist within a range where the x coordinate in the chromaticity diagram is 0.5 or more and the y coordinate is 0.4 or more. The second chromaticity coordinates exist within a range where the x coordinate is 0.2 or less and the y coordinate is 0.1 or less. When the color difference is represented by Δxy and the luminous flux of the illumination light is represented by φ, formula 1 is Δxy=a×(log 10 φ+p) 4 +b×(log 10 φ+p) 3 +c×(log 10 φ+p) 2 +d×(log 10 φ+p)+e …(Formula 1) (However, the coefficients a, b, c, d, e, p are a = -0.0923, b = 0.0417, c = -0.04416, d = -0.3339, e = 0.5748, p ≤ 0.4, respectively.)

Description

[Technical Field]

[0001] This disclosure relates to lighting systems, lighting methods, and programs, and more particularly to lighting systems for color-tuning lighting light, lighting methods in said lighting systems, and programs for performing said lighting methods. [Background technology]

[0002] Stage lighting and other types of performance lighting often involve adjusting (color tuning) the color of the light source. One method for color tuning lighting is to combine a light source that emits monochromatic light (for example, a halogen lamp) with a color filter (see, for example, Patent Document 1).

[0003] Furthermore, in recent years, lighting systems that use LEDs as the light source instead of halogen lamps have become popular in the field of stage lighting. In LED lighting systems, multiple types of LEDs with different light colors, for example, three LEDs of red, green, and blue, are used, and by mixing these three colors of light in any ratio, it is possible to achieve light colors equivalent to those achieved by a combination of halogen lamps and color filters. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2013-077491 [Overview of the project] [Problems that the invention aims to solve]

[0005] Incidentally, the lighting systems described above sometimes gradually transition from one light color to another. In such cases, a lighting system using multiple types of LEDs with different light colors may produce a more unnatural change in light color during the transition compared to a lighting system that combines halogen lamps and color filters.

[0006] The purpose of this disclosure is to provide a lighting system, lighting method, and program that can reduce the sense of unnaturalness when transitioning between light colors. [Means for solving the problem]

[0007] A lighting system according to one aspect of the present disclosure comprises a light source unit that outputs illumination light, a power supply unit that supplies power to the light source unit, and an adjustment unit that controls the power supply unit and adjusts the power supplied to the light source unit. The light source unit has a plurality of types of light-emitting elements with different light colors. The power supply unit is configured to supply power separately to each of the plurality of types of light-emitting elements of the same type. The adjustment unit adjusts the ratio of the amount of power supplied to the plurality of types of light-emitting elements so that the chromaticity coordinates of the illumination light output from the light source unit match a target value. When the adjustment unit transitions the chromaticity coordinates of the illumination light from a first chromaticity coordinate in the range where the x-coordinate is 0.5 or more and the y-coordinate is 0.4 or more in the chromaticity diagram to a second chromaticity coordinate in the range where the x-coordinate is 0.2 or less and the y-coordinate is 0.1 or less, the color difference between the first chromaticity coordinate and the chromaticity coordinate during the transition is expressed as Δxy, and the luminous flux of the illumination light is expressed as φ, then the following equation 1 Δxy = a × (log 10 φ+p) 4 +b × (log 10 φ+p) 3 +c × (log 10 φ+p) 2 +d × (vector) 10 φ+p)+e …(Formula 1) (However, the coefficients a, b, c, d, e, and p are a=-0.0923, b=0.0417, c=-0.04416, d=-0.3339, e=0.5748, and p≦0.4, respectively.) The system calculates the luminous flux required to achieve the condition, and based on the calculated luminous flux, it calculates the luminous flux for each of the multiple types of light-emitting elements and controls the power supply unit.

[0008] A lighting system according to one aspect of the present disclosure includes a light source unit that outputs illumination light, a power supply unit that supplies power to the light source unit, and an adjustment unit that controls the power supply unit to adjust the power supplied to the light source unit. The light source unit has a plurality of types of light-emitting elements having different light colors from each other. The power supply unit is configured to be able to supply power separately to the same type of the plurality of types of light-emitting elements. The adjustment unit adjusts the ratio of the power supply amounts to the plurality of types of light-emitting elements so that the chromaticity coordinates of the illumination light output from the light source unit match a target value. When the adjustment unit transitions the chromaticity coordinates of the illumination light from a second chromaticity coordinate existing within a range where the x coordinate is 0.2 or less and the y coordinate is 0.1 or less in a chromaticity diagram to a first chromaticity coordinate existing within a range where the x coordinate is 0.5 or more and the y coordinate is 0.4 or more, the color difference between the second chromaticity coordinate and the chromaticity coordinate during the transition is represented as Δxy, and when the luminous flux of the illumination light is represented as φ, the following formula 2 Δxy=a×(log 10 φ+p) 4 +b×(log 10 φ+p) 3 +c×(log 10 φ+p) 2 +d×(log 10 φ+p) …(Formula 2) (However, the coefficients a, b, c, d, and p are a = -0.0923, b = -0.0417, c = 0.04331, d = 0.3288, and -0.6 ≤ p, respectively.) calculates the luminous flux that satisfies the formula, calculates the luminous flux of each of the plurality of types of light-emitting elements based on the calculated luminous flux, and controls the power supply unit.

[0009] An illumination method according to one aspect of the present disclosure adjusts the ratio of power supplied to the multiple types of light-emitting elements so that the chromaticity coordinates of the illumination light output from a light source having multiple types of light-emitting elements with different light colors match a target value. When the illumination method transitions the chromaticity coordinates of the illumination light from a first chromaticity coordinate in the range where the x-coordinate is 0.5 or more and the y-coordinate is 0.4 or more in the chromaticity diagram to a second chromaticity coordinate in the range where the x-coordinate is 0.2 or less and the y-coordinate is 0.1 or less, the color difference between the first chromaticity coordinate and the chromaticity coordinate during the transition is expressed as Δxy, and the luminous flux of the illumination light is expressed as φ, then the following equation 1 Δxy = a × (log 10 φ+p) 4 +b × (log 10 φ+p) 3 +c × (log 10 φ+p) 2 +d × (vector) 10 φ+p)+e …(Formula 1) (However, the coefficients a, b, c, d, e, and p are a=-0.0923, b=0.0417, c=-0.04416, d=-0.3339, e=0.5748, and p≦0.4, respectively.) The luminous flux required to achieve the condition is calculated, and based on the calculated luminous flux, the luminous flux of each of the multiple types of light-emitting elements is calculated to change the luminous flux output from the multiple types of light-emitting elements.

[0010] An illumination method according to one aspect of the present disclosure adjusts the ratio of power supplied to the multiple types of light-emitting elements so that the chromaticity coordinates of the illumination light output from a light source having multiple types of light-emitting elements with different light colors match a target value. When the illumination method transitions the chromaticity coordinates of the illumination light from a second chromaticity coordinate in the range where the x-coordinate is 0.2 or less and the y-coordinate is 0.1 or less in the chromaticity diagram to a first chromaticity coordinate in the range where the x-coordinate is 0.5 or more and the y-coordinate is 0.4 or more, the color difference between the second chromaticity coordinate and the chromaticity coordinate during the transition is expressed as Δxy, and the luminous flux of the illumination light is expressed as φ, then the following equation 2 Δxy = a × (log 10 φ+p) 4 +b × (log 10 φ+p)3 +c × (log 10 φ+p) 2 +d × (vector) 10 φ+p) …(Formula 2) (However, the coefficients a, b, c, d, and p are a=-0.0923, b=-0.0417, c=0.04331, d=0.3288, and -0.6≦p, respectively.) The luminous flux required to achieve the condition is calculated, and based on the calculated luminous flux, the luminous flux of each of the multiple types of light-emitting elements is calculated to change the luminous flux output from the multiple types of light-emitting elements.

[0011] A program relating to one aspect of this disclosure causes a computer system to execute the illumination method. [Effects of the Invention]

[0012] The lighting system, lighting method, and program disclosed herein have the effect of reducing the sense of unnaturalness when transitioning between light colors. [Brief explanation of the drawing]

[0013] [Figure 1] Figure 1 is a block diagram of a lighting system according to an embodiment of the present disclosure. [Figure 2] Figure 2 is a detailed system configuration diagram of the lighting system described above. [Figure 3] Figure 3 is a perspective view of the lighting device in the same lighting system. [Figure 4] Figure 4 is a chromaticity diagram used to explain the operation of the lighting system described above. [Figure 5] Figure 5 is a characteristic diagram illustrating the operation of the lighting system described above. [Figure 6] Figure 6 shows the relationship between color difference and luminous flux during the transition in the same lighting system. [Figure 7] Figure 7 shows the relationship between color difference and luminous flux during the transition in the same lighting system. [Figure 8] Figure 8 is a table showing the relationship between color difference and luminous flux during the transition in the same lighting system. [Figure 9] Figure 9 shows the relationship between color difference and luminous flux during the transition in the same lighting system. [Figure 10] Figure 10 shows the relationship between color difference and luminous flux during the transition in the same lighting system. [Figure 11] Figure 11 shows the relationship between color difference and luminous flux during the transition in the same lighting system. [Modes for carrying out the invention]

[0014] Hereinafter, the lighting system, lighting method, and program according to embodiments of this disclosure will be described in detail with reference to the drawings. However, the configurations described in the following embodiments are merely examples of this disclosure. This disclosure is not limited to the following embodiments, and various modifications are possible depending on the design, etc., as long as the effects of this disclosure can be achieved.

[0015] (1) Overview The lighting system S1 according to this embodiment includes a light source unit 1 that outputs illumination light, a power supply unit 2 that supplies power to the light source unit 1, and an adjustment unit 3 that controls the power supply unit 2 to adjust the power supplied to the light source unit 1 (see Figure 1).

[0016] The light source unit 1 has multiple types of light-emitting elements with different light colors. For example, the light source unit 1 has light-emitting diodes (red LEDs) that output red light, light-emitting diodes (green LEDs) that output green light, and light-emitting diodes (blue LEDs) that output blue light. In other words, the light source unit 1 can not only output illumination light of each light color individually, but can also output illumination light of a different light color by mixing the illumination light of each light color. In this embodiment, "color tuning" means adjusting the light color of the illumination light by changing the ratio of mixing the illumination light of multiple types. In this embodiment, "dimming" means adjusting the light intensity of each illumination light while maintaining the ratio of mixing the illumination light of multiple types.

[0017] The power supply unit 2 is configured to supply power separately to each of the same type of light-emitting elements among multiple types of light-emitting elements. For example, if the light source unit 1 has three LEDs, a red LED, a green LED, and a blue LED, the power supply unit 2 has a power supply circuit for supplying power to the red LED, a power supply circuit for supplying power to the green LED, and a power supply circuit for supplying power to the blue LED. Each of these power supply circuits has a DC / DC converter, such as a buck converter (step-down chopper circuit). The DC / DC converter in each power supply circuit can adjust (increase or decrease) its output current.

[0018] The adjustment unit 3 adjusts the ratio of power supplied to multiple types of light-emitting elements so that the chromaticity coordinates of the illumination light output from the light source unit 1 match the target value. In this embodiment, the chromaticity coordinates are the chromaticity coordinates (x,y) in the XYZ color system (see Figure 4). For example, consider a case where the light source unit 1 has three LEDs: a red LED, a green LED, and a blue LED, and the power supply unit 2 has a power supply circuit for supplying power to the red LED, a power supply circuit for supplying power to the green LED, and a power supply circuit for supplying power to the blue LED. In this case, the adjustment unit 3 can adjust the color and brightness of the illumination light output from the light source unit 1 by adjusting the output current of the power supply circuit for the red LED, the power supply circuit for the green LED, and the power supply circuit for the blue LED.

[0019] Furthermore, when the chromaticity coordinate of the illumination light transitions from the first chromaticity coordinate M1 to the second chromaticity coordinate M2, the adjustment unit 3 calculates the luminous flux that satisfies the following equation 1, and controls the power supply unit 2 by calculating the luminous flux of each of the multiple types of light-emitting elements based on the calculated luminous flux. The first chromaticity coordinate M1 is within the range where the x-coordinate is 0.5 or greater and the y-coordinate is 0.4 or greater in the chromaticity diagram (see Figure 4). The second chromaticity coordinate M2 is within the range where the x-coordinate is 0.2 or less and the y-coordinate is 0.1 or less (see Figure 4). Equation 1 is expressed as follows when the color difference between the first chromaticity coordinate M1 and the chromaticity coordinate during the transition is expressed as Δxy, and the luminous flux of the illumination light is expressed as φ.

[0020] Δxy = a × (log 10 φ+p) 4 +b × (log 10φ+p) 3 +c × (log 10 φ+p) 2 +d × (vector) 10 φ+p)+e …(Formula 1) The coefficients a, b, c, d, e, and p are a=-0.0923, b=0.0417, c=-0.04416, d=-0.3339, e=0.5748, and p≦0.4, respectively. Note that the color difference Δxy represents the distance between the two chromaticity coordinates on the chromaticity diagram.

[0021] Here, the lighting system S1 according to this embodiment may be used for stage lighting. In stage lighting, the light intensity and color may be gradually changed when transitioning from one lighting state to another. For example, when transitioning from an evening scene to a night scene, the chromaticity coordinates may be changed from those corresponding to the evening scene (first chromaticity coordinate M1) to those corresponding to the night scene (second chromaticity coordinate M2). In this case, the chromaticity coordinates of the illuminating light during the transition (chromaticity coordinates M8 to M10) pass through a white region (a region including the blackbody locus and its surroundings) (see Figure 4). The solid line β1 in Figure 5 represents the change in illuminating light when transitioning from an evening scene to a night scene using a lighting system combining a halogen lamp and a color filter. The horizontal axis in Figure 5 represents the color difference Δxy between the chromaticity coordinate M1 corresponding to the evening scene and the chromaticity coordinate of the illuminating light during the transition. Furthermore, the vertical axis in Figure 5 represents the luminous flux of the illumination light during the transition, as a relative value with the luminous flux of the illumination light at the first chromaticity coordinate M1 corresponding to the evening scene set to 100. In addition, the dashed line α0 in Figure 5 represents the change in illumination light when transitioning from an evening scene to a night scene using an illumination system with multiple types of LEDs.

[0022] As shown by the solid line β1, in a lighting system combining a halogen lamp and a color filter, the luminous flux of the illumination light decreases to 15 or less when the color difference Δxy is around 0.1 to 0.2. In other words, in a lighting system combining a halogen lamp and a color filter, the luminous flux when the chromaticity coordinates M8 to M10 of the illumination light pass through the white region during the transition is relatively very low, making it less likely to cause discomfort to the observer (such as an audience member watching a stage performance).

[0023] On the other hand, as shown by the dashed line α0, in a lighting system using LEDs of multiple light colors, if the luminous flux of the illumination light is linearly reduced in response to a change in color difference Δxy, the luminous flux of the illumination light around a color difference Δxy of 0.1 to 0.2 only decreases to about 70. In other words, in a lighting system using LEDs of multiple light colors, if the luminous flux of the illumination light is linearly reduced in response to a change in color difference Δxy, the luminous flux when the chromaticity coordinates M8 to M10 of the illumination light pass through the white region during the transition is relatively very high, which tends to cause discomfort to the observer.

[0024] In contrast, the illumination system S1 according to this embodiment calculates a luminous flux φ that satisfies the following equation 1 when transitioning the chromaticity coordinate of the illumination light from a first chromaticity coordinate M1 to a second chromaticity coordinate M2, and calculates the respective luminous fluxes φ1, φ2, ... of multiple types of light-emitting elements based on the calculated luminous flux φ, causing the adjustment unit 3 to control the power supply unit 2. The respective luminous fluxes φ1, φ2, ... of multiple types of light-emitting elements are selected by multiplying the total luminous flux φ of the illumination light by the ratio of the illumination light of each light-emitting element corresponding to the chromaticity coordinate during the transition.

[0025] Δxy = a × (log 10 φ+p) 4 +b × (log 10 φ+p) 3 +c × (log 10 φ+p) 2 +d × (vector) 10 φ+p)+e …(Formula 1) However, the coefficients a, b, c, d, e, and p are a=-0.0923, b=0.0417, c=-0.04416, d=-0.3339, e=0.5748, and p≦0.4, respectively.

[0026] However, in the embodiment, when the chromaticity coordinate of the illumination light transitions from the first chromaticity coordinate M1 to the second chromaticity coordinate M2, the lighting system S1 calculates the luminous fluxes φ1, φ2, ... of each of the multiple types of light-emitting elements based on the luminous flux φ that satisfies equation 1, and causes the adjustment unit 3 to control the power supply unit 2. As shown by the dashed line α1 in Figure 6, the luminous flux when the chromaticity coordinate of the illumination light passes through the white region during the transition can be reduced. As a result, the lighting system S1 in the embodiment can reduce the sense of incongruity when transitioning light colors by reducing the luminous flux of the white illumination light that appears during the transition, compared to the case where the luminous flux of the illumination light during the transition is changed linearly.

[0027] Furthermore, when the chromaticity coordinate of the illumination light transitions from the second chromaticity coordinate M2 to the first chromaticity coordinate M1, the adjustment unit 3 calculates the luminous flux that satisfies the following equation 2, and based on the calculated luminous flux, calculates the luminous flux of each of the multiple types of light-emitting elements and controls the power supply unit 2.

[0028] Δxy = a × (log 10 φ+p) 4 +b × (log 10 φ+p) 3 +c × (log 10 φ+p) 2 +d × (vector) 10 φ+p) …(Formula 2) However, the coefficients a, b, c, d, and p are a=-0.0923, b=-0.0417, c=0.04331, d=0.3288, and -0.6≦p, respectively.

[0029] However, in the embodiment, when the chromaticity coordinate of the illumination light transitions from the second chromaticity coordinate M2 to the first chromaticity coordinate M1, the lighting system S1 calculates the luminous fluxes φ1, φ2, ... of each of the multiple types of light-emitting elements based on the luminous flux φ that satisfies equation 2, and causes the adjustment unit 3 to control the power supply unit 2. As a result, the luminous flux when the chromaticity coordinate of the illumination light passes through the white region during the transition can be reduced. Consequently, compared to the case where the luminous flux of the illumination light during the transition is changed linearly, the lighting system S1 in the embodiment can reduce the sense of incongruity when transitioning between light colors by reducing the luminous flux of the white illumination light that appears during the transition.

[0030] (2) Details Next, the lighting system S1 according to the embodiment (hereinafter referred to as lighting system S1) will be described in detail with reference to the drawings.

[0031] The lighting system S1 comprises a light source unit 1, a power supply unit 2, and an adjustment unit 3 (see Figure 1). Furthermore, the lighting system S1 comprises a storage unit 4, a communication unit 5, an input receiving unit 6, and a display unit 7 (see Figure 2). In the lighting system S1, the power supply unit 2, adjustment unit 3, storage unit 4, communication unit 5, input receiving unit 6, and display unit 7 are components of the lighting control device A1. The lighting device B1 in the lighting system S1 comprises the lighting control device A1 and the light source unit 1.

[0032] (2-1) Lighting device Lighting device B1 is a so-called cyclorama light (lower cyclorama light) used to illuminate the background surface (cyclorama surface) of a television studio or a theater stage (stage lighting) (see Figure 3). However, lighting device B1 may be a lighting device other than a lower cyclorama light, such as an upper cyclorama light, border light, spotlight, or floodlight.

[0033] The lighting device B1 includes a pair of support parts that support the light source unit 1 relative to the lighting control device A1, and a pair of connecting parts 81 (see Figure 3).

[0034] (2-2) Light source section The light source unit 1 includes multiple LED modules, multiple lens blocks, a panel 17, and a second housing 16, among other things.

[0035] Each of the multiple LED modules is constructed by mounting five different types of LEDs, each with a different light color, onto a rectangular substrate. The five types of LEDs have light colors of red, green, blue, amber, and emerald green. In the following description, the green LED will be referred to as the 1st LED11, the amber LED as the 2nd LED12, the blue LED as the 3rd LED13, the emerald green LED as the 4th LED14, and the red LED as the 5th LED15. Multiple units of each of the five types of LEDs are mounted on the surface of the substrate. However, the types (light colors) and number of LEDs in this embodiment are merely examples, and the number of light colors may be four or fewer, or six or more.

[0036] Among the various types of LEDs, LEDs of the same type (same light color) are electrically connected to each other by printed wiring formed on the surface of the circuit board. The ends of these printed wirings are electrically connected to multiple current output units (first current output unit 21, second current output unit 22, third current output unit 23, fourth current output unit 24, and fifth current output unit 25) of the power supply unit 2 of the lighting control device A1 via multiple connectors mounted on the circuit board, as will be described later (see Figure 3).

[0037] Each of the multiple lens blocks has multiple lens sections. These multiple lens sections control the light distribution of the light emitted from the multiple LEDs. The multiple lens sections are integrally formed from a translucent synthetic resin material such as polycarbonate resin or acrylic resin.

[0038] Panel 17 is formed in the shape of a rectangular flat plate from a light-transmitting synthetic resin (for example, acrylic resin or polycarbonate resin) (see Figure 3). However, panel 17 is configured to diffuse transmitted light (light whose distribution is controlled by multiple lens blocks) by filling the synthetic resin with fillers such as titanium dioxide, glass beads, or mica. Alternatively, panel 17 may be configured to diffuse transmitted light by applying a textured or uneven surface to its front or back surface.

[0039] The second housing 16 is formed from a metal material such as aluminum or an aluminum alloy and is a long, box-shaped structure with an open front (see Figure 3). Multiple LED modules are housed inside the second housing 16 with the sides on which the LEDs are mounted facing the front of the second housing 16. Multiple lens blocks are also housed inside the second housing 16 so as to cover the front of the multiple LED modules. The opening on the front of the second housing 16 is covered by a panel 17.

[0040] The light source unit 1 is supported by a pair of support parts in the first housing 80 of the lighting control device A1. Each of the support parts is made up of a hinge. In other words, the light source unit 1 is rotatably supported relative to the first housing 80 by the pair of support parts (hinges).

[0041] Furthermore, the light source unit 1 is mechanically connected to the first housing 80 by a pair of connecting parts 81. Each of the pair of connecting parts 81 is formed from an arc-shaped metal plate. The pair of connecting parts 81 are mechanically coupled to the second housing 16 of the light source unit 1 at one end in the circumferential direction and screwed to the first housing 80 at the other end in the circumferential direction. However, each of the pair of connecting parts 81 is provided with a plurality of screw insertion holes 82 arranged in two rows along the circumferential direction.

[0042] Therefore, the light source unit 1 is rotatably supported by a pair of support members, and can be fixed at any rotation angle by being screwed to the first housing 80 with thumb screws 83 inserted through any of the screw insertion holes 82.

[0043] (2-3) Lighting control device The lighting control device A1 comprises a power supply unit 2, an adjustment unit 3, a storage unit 4, a communication unit 5, an input receiving unit 6, and a display unit 7 (see Figure 2).

[0044] The power supply unit 2 includes an AC / DC converter 20 and five current output units that correspond one-to-one with five types of LEDs. The AC / DC converter 20 is configured to convert the AC voltage supplied from an external power supply P1 (for example, an AC power supply with an effective value of 100V) into a DC voltage and supply it to each current output unit. The AC / DC converter 20 includes, for example, a full-wave rectifier (diode bridge) and a boost chopper circuit for power factor correction. The output terminal of the AC / DC converter 20 is electrically connected in parallel with the input terminals of the five current output units.

[0045] The five current output units include a first current output unit 21, a second current output unit 22, a third current output unit 23, a fourth current output unit 24, and a fifth current output unit 25. The first current output unit 21 outputs a DC current to the first LED 11. The second current output unit 22 outputs a DC current to the second LED 12. The third current output unit 23 outputs a DC current to the third LED 13. The fourth current output unit 24 outputs a DC current to the fourth LED 14. The fifth current output unit 25 outputs a DC current to the fifth LED 15. However, the five current output units share a common circuit configuration. Each current output unit has a DC / DC converter such as a buck converter (step-down chopper circuit). The DC / DC converter of each current output unit allows for adjustment (increase or decrease) of the output current.

[0046] The communication unit 5 is configured to communicate with an external lighting console C1 via a communication cable. The communication unit 5 has the function of sending and receiving digital control signals (hereinafter referred to as DMX signals) compliant with a communication standard suitable for lighting control, such as DMX (Digital Multiplex) 512A, to and from the lighting console C1. However, the communication unit 5 may also have the function of sending and receiving control signals compliant with communication standards other than DMX 512A, such as DALI (Digital Addressable Lighting Interface: registered trademark), or wired LAN standards such as 100BASE-T and 1000BASE-T. The communication unit 5 transmits the control data contained in the DMX signals received from the lighting console C1 to the adjustment unit 3 via serial communication, such as UART (Universal Asynchronous Receiver / Transmitter).

[0047] The adjustment unit 3 mainly consists of a microcontroller. The microcontroller of the adjustment unit 3 acquires control data from the communication unit 5 by performing serial communication with the communication unit 5. The adjustment unit 3 executes a lighting control program using the microcontroller, and in response to control commands (DMX signals) received from the dimming console C1 via the communication unit 5, controls each current output unit to perform functions such as blinking, dimming, and color adjustment of the light source unit 1 (multiple LEDs).

[0048] By the way, there are two types of dimming methods in which the adjustment unit 3 adjusts the brightness of multiple LEDs by increasing or decreasing the output current of each current output unit. One is a dimming method that changes the magnitude of the current that flows continuously through the LED, and is usually called the DC dimming method. The other is a dimming method that periodically turns the power supply to the LED on and off and changes the ratio of the power supply period (on duty cycle), and is usually called the burst dimming method.

[0049] In DC dimming systems, the peak value of the current flowing through the switching element of the DC / DC converter is typically increased or decreased, and the switching element is controlled in a current-critical mode. However, in DC dimming systems, there is a limit (lower limit) to the on-period (on-width) of the drive signal applied to the switching element, making deep dimming (illumination at low dimming levels) more difficult compared to burst dimming systems. The dimming level is expressed as a current ratio, with the light output when the rated current is flowing through the LED being 100%.

[0050] Therefore, the adjustment unit 3 controls each current output unit using a burst dimming method when the dimming level is below the threshold, and controls each current output unit using a DC dimming method when the dimming level is above the threshold. The threshold for the dimming level is preferably around 20% to 30%.

[0051] Furthermore, the five different colors of light emitted from the five types of LEDs are mixed during the process of light distribution control by the lens block and transmission through the panel 17. In other words, the color of the light emitted from the light source 1 is determined by the ratio of the dimming levels of the five types of LEDs.

[0052] Here, the chromaticity coordinates of the five types of LEDs are shown in the chromaticity diagram of Figure 4. Figure 4 is the xy chromaticity diagram of the XYZ color system. In Figure 4, the chromaticity points W1, W2, W3, W4, and W5 represent the chromaticity coordinates of the first LED 11, the second LED 12, the third LED 13, the fourth LED 14, and the fifth LED 15, respectively. In other words, the adjustment unit 3 can realize any light color with arbitrary chromaticity coordinates in a pentagonal region with the five chromaticity points W1, W4, W2, W5, and W3 as vertices, according to the ratio of the dimming levels of the five types of LEDs.

[0053] Furthermore, the adjustment unit 3 can adjust the dimming level of each type of LED while maintaining the ratio of the dimming levels of the five types of LEDs, thereby enabling dimming of light (luminous flux) of any desired color.

[0054] The input receiving unit 6 has multiple tact switches (push-button switches) (see Figure 3). The input receiving unit 6 receives operation input from the operator in response to the pressing of these tact switches. The operation input received by the input receiving unit 6 (for example, a voltage signal corresponding to a press operation) is taken up by the adjustment unit 3 (microcontroller).

[0055] The display unit 7 has four 7-segment displays (see Figure 3). Each 7-segment display can display 10 numbers from "0" to "9" and several letters such as "A", "F", "U", "c", "h", and "n". These four 7-segment displays are controlled by the adjustment unit 3 (microcontroller).

[0056] The adjustment unit 3 sets the dimming level and other settings according to the operation input received from the input reception unit 6. The adjustment unit 3 also displays the dimming level and other settings currently being received by the input reception unit 6 on the display unit 7. In other words, the operator can operate the device while confirming the dimming level and other settings by the numbers and letters displayed on the display unit 7.

[0057] The storage unit 4 includes an electrically rewritable non-volatile semiconductor memory such as flash memory, or a magnetic storage device such as a hard disk drive or a memory card. However, the contents to be stored in the storage unit 4 will be described later.

[0058] (2-4) Operation of the lighting system Next, the operation of the lighting system S1 will be explained. The lighting system S1 controls the blinking (switching between on and off), dimming, and color adjustment of the light source unit 1 based on DMX signals transmitted from the lighting console C1 to the lighting control device A1. Specifically, the communication unit 5 of the lighting control device A1 receives the DMX signal, and based on the control commands contained in the received DMX signal, the adjustment unit 3 of the lighting control device A1 controls the power supply unit 2 to control the blinking, dimming, and color adjustment of the light source unit 1. The control commands given from the lighting console C1 to the lighting control device A1 may be created in real time by the operator's actions, or they may be created in advance by the operator and stored in the memory of the lighting console C1. These control commands are given for each of the five types of LEDs. For example, the color adjustment control command specifies the ratio of the dimming levels of the five types of LEDs from the first LED 11 to the fifth LED 15. For example, let's assume that the light color is adjusted so that the ratio of the dimming levels of the five types of LEDs is 1:1:1:2:1. In this case, if the dimming level of the fourth LED14, which has the highest ratio, is set to 100%, then the dimming levels of the other four types of LEDs will be 50%. Furthermore, if the light intensity is halved without changing the color of light, then if the dimming level of the fourth LED14, which has the highest ratio, is set to 50%, then the dimming levels of the other four types of LEDs will be 25%.

[0059] Here, the lighting system S1 stores multiple types of lighting states (scene information) in the memory unit 4 of the lighting control device A1, associating them with scene numbers. Each scene information consists of a combination of dimming levels for five types of LEDs. For example, in the scene information corresponding to an evening scene (scene information for scene number 1), the ratio of the dimming levels of green (1st LED 11), amber (2nd LED 12), blue (3rd LED 13), emerald green (4th LED 14), and red (5th LED 15) is set to approximately 1:2.58:0:0:0. Similarly, in the scene information corresponding to a night scene (scene information for scene number 2), the ratio of the dimming levels of green (1st LED 11), amber (2nd LED 12), blue (3rd LED 13), emerald green (4th LED 14), and red (5th LED 15) is set to approximately 0:0:24.4:5:1. However, memory unit 4 also stores scene information representing scenes other than evening and night scenes. Of the scene information stored in memory unit 4, lighting conditions (scene information) that match or approximate lighting conditions achieved by a combination of halogen lamps and color filters may be associated with the scene number, or, instead of the scene number, with the number of the color filter combined with the halogen lamp. For example, the light color (Polycolor) often used to create evening scenes is achieved by a combination of color filter No. 40 and a halogen lamp. Similarly, the light color (Polycolor) often used to create night scenes is achieved by a combination of color filter No. 72 and a halogen lamp. The correspondence between Polycolor and color filters is publicly available from the Lighting Division of the Japan Association of Theatre and Performing Arts Technology.

[0060] As explained in the overview, in stage lighting, for example, when transitioning from an evening scene to a night scene, the chromaticity coordinate M1 corresponding to the evening scene is sometimes transitioned to the chromaticity coordinate M2 corresponding to the night scene (see Figure 4). In this case, the chromaticity coordinates M3 to M11 of the illuminating light during the transition pass through the white region (see Figure 4). As shown by the solid line β1 in Figure 5, in a lighting system that combines a halogen lamp and a color filter, the luminous flux of the illuminating light near a color difference Δxy of 0.1 to 0.2 is reduced to 15 or less, making it less likely to cause discomfort to the observer (such as an audience member watching a stage performance).

[0061] On the other hand, as shown by the dashed line α0, in a lighting system using LEDs of multiple light colors, if the luminous flux of the illumination light is linearly reduced in response to a change in color difference Δxy, the luminous flux of the illumination light around a color difference Δxy of 0.1 to 0.2 only decreases to about 70. In other words, in a lighting system using LEDs of multiple light colors, if the luminous flux of the illumination light is linearly reduced in response to a change in color difference Δxy, the luminous flux when the chromaticity coordinate of the illumination light passes through the white region during the transition is relatively very high, which tends to cause discomfort to the observer.

[0062] In contrast, the illumination system S1 according to this embodiment calculates a luminous flux φ that satisfies the following equation 1 when transitioning the chromaticity coordinate of the illumination light from a first chromaticity coordinate M1 to a second chromaticity coordinate M2, and calculates the respective luminous fluxes φ1, φ2, ... of multiple types of light-emitting elements based on the calculated luminous flux φ, causing the adjustment unit 3 to control the power supply unit 2. The respective luminous fluxes φ1, φ2, ... of multiple types of light-emitting elements are selected by multiplying the total luminous flux φ of the illumination light by the ratio of the illumination light of each light-emitting element corresponding to the chromaticity coordinate during the transition.

[0063] Δxy = a × (log 10 φ+p) 4 +b × (log 10 φ+p) 3 +c × (log 10 φ+p) 2 +d × (vector) 10 φ+p)+e …(Formula 1) However, the coefficients a, b, c, d, e, and p are a=-0.0923, b=0.0417, c=-0.04416, d=-0.3339, e=0.5748, and p≦0.4, respectively.

[0064] The inventors experimentally determined Equation 1. Specifically, in a lighting system combining a halogen lamp and a color filter, the inventors measured the luminous flux of multiple chromaticity coordinates M3 to M11 during the transition from a first chromaticity coordinate M1 corresponding to an evening scene to a second chromaticity coordinate M2 corresponding to a night scene. From these measured luminous flux values ​​and the color difference Δxy between the first chromaticity coordinate M1 and each chromaticity coordinate M3 to M11, the inventors derived Equation 1 as a relational expression that coincides with or approximates the solid line β1 in Figure 6. Note that Equation 1 almost coincides with the solid line β1 when the coefficient p is zero, and deviates from the solid line β1 as the absolute value of the coefficient p increases. For example, when the coefficient p is a positive value (p=0.2), it passes through a region lower than the solid line β1, as shown by the dashed line α2, and when the coefficient p is a negative value (p=-0.2), it passes through a region higher than the solid line β1, as shown by the dashed line α3.

[0065] Figure 8 shows the results of calculating the luminous flux ratio of the five types of LEDs for each chromaticity coordinate M1 to M11 using Equation 1 above. For example, at the first chromaticity coordinate M1 (color difference Δxy is 0.000), the luminous flux ratio of the first LED11 to the fifth LED15 is 27.91:72.09:0:0:0. Also, at the second chromaticity coordinate M2 (color difference Δxy is 0.563), the luminous flux ratio of the first LED11 to the fifth LED15 is 0:0:1.22:0.25:0.05. In other words, when transitioning from the first chromaticity coordinate M1 to the second chromaticity coordinate M2, the luminous flux of the first LED11 and the second LED12 decreases, while the luminous flux of the third LED13, fourth LED14, and fifth LED15 increases, and the luminous flux of the illumination light decreases.

[0066] Here, it is desirable that the lighting system S1 stores the results (see Figure 8) of the luminous flux ratios of the five types of LEDs for each chromaticity coordinate M1 to M11, calculated by the adjustment unit 3, in the memory unit 4 of the lighting control device A1. When the adjustment unit 3 of the lighting control device A1 receives a control command from the dimmer console C1 instructing it to transition from the first chromaticity coordinate M1 to the second chromaticity coordinate M2, it refers to the calculation results stored in the memory unit 4 and controls the power supply unit 2 so that the luminous flux of each of the first LED 11 to fifth LED 15 at each chromaticity coordinate M3 to M11 during the transition satisfies the luminous flux ratio in the calculation result. It is also desirable that the adjustment unit 3 can set the transition time when transitioning from the first chromaticity coordinate M1 to the second chromaticity coordinate M2. The transition time may be included in the control command instructing it to transition from the first chromaticity coordinate M1 to the second chromaticity coordinate M2.

[0067] However, when the lighting system S1 transitions the chromaticity coordinate of the illumination light from the first chromaticity coordinate M1 to the second chromaticity coordinate M2 as described above, it calculates the luminous flux φ1 to φ5 of each of the five types of LEDs (first LED 11, second LED 12, third LED 13, fourth LED 14, fifth LED 15) based on the luminous flux φ that satisfies equation 1, and causes the adjustment unit 3 to control the power supply unit 2. As a result, the lighting system S1 can reduce the luminous flux when the chromaticity coordinates M3 to M11 of the illumination light pass through the white region during the transition, as shown by the dashed line α1 in Figure 6. Consequently, compared to the case where the luminous flux of the illumination light during the transition is changed linearly, the lighting system S1 can reduce the sense of incongruity when transitioning light colors by reducing the luminous flux of the white illumination light that appears during the transition.

[0068] Here, the elliptical region on the chromaticity diagram where any chromaticity coordinate is perceived as the same color visually is called the MacAdam ellipse. In other words, the chromaticity coordinates M3 to M11 of the illuminating light during the transition do not necessarily have to lie on the dashed line α1; for example, they may lie in the region enclosed by the dashed lines α2 and α3 in Figure 7. Alternatively, the chromaticity coordinates M3 to M11 of the illuminating light during the transition may lie in the region enclosed by the dashed line α3 and the horizontal axis (color difference Δxy) and vertical axis (luminous flux φ), as shown in Figure 9. In other words, if the chromaticity coordinates M3 to M11 of the illuminating light during the transition lie in these regions, they will be perceived as almost the same color visually as when they lie on the dashed line α1.

[0069] Therefore, it is preferable for the lighting system S1 to have the adjustment unit 3 calculate the luminous flux φ that satisfies Equation 1 by setting the coefficient p in Equation 1 to 0.4 or less or 0.2 or less. Alternatively, the lighting system S1 may have the adjustment unit 3 calculate the luminous flux φ that satisfies Equation 1 by setting the coefficient p in Equation 1 to -0.4 or more and 0.4 or less or -0.2 or more and 0.2 or less. By reducing the absolute value of the coefficient p in Equation 1 and having the adjustment unit 3 calculate the luminous flux φ, the lighting system S1 can bring the color of the illumination light output from the light source unit 1 closer to the color of light produced by a combination of a halogen lamp and a color filter.

[0070] However, among the chromaticity coordinates M3 to M11 during the transition, only the range of chromaticity coordinates M9 to M10 overlaps with the white region. The color difference Δxy of chromaticity coordinates M9 and M10 is 0.188 and 0.399, respectively (see Figure 8). Therefore, if the lighting system S1 has the adjustment unit 3 calculate the luminous flux φ that satisfies equation 1 by setting the coefficient p to 0.2 or less when the color difference Δxy is 0.1 or greater, the luminous flux of the white illumination light that appears during the transition can be reduced, thereby reducing the sense of incongruity when the light color is transitioned.

[0071] Incidentally, in stage lighting, there are instances where the chromaticity coordinate of the lighting light is transitioned from a second chromaticity coordinate M2 to a first chromaticity coordinate M1. In this case, in a lighting system combining a halogen lamp and a color filter, the luminous flux φ of the lighting light changes with respect to the color difference Δxy between the second chromaticity coordinate M2 and the chromaticity coordinate during the transition, as shown by the solid line β2 in Figure 10.

[0072] When the lighting system S1 transitions the chromaticity coordinate of the illumination light from the second chromaticity coordinate M2 to the first chromaticity coordinate M1, it calculates the luminous flux φ that satisfies the following equation 2, and based on the calculated luminous flux φ, it calculates the luminous fluxes φ1, φ2, ... of multiple types of light-emitting elements and causes the adjustment unit 3 to control the power supply unit 2.

[0073] Δxy = a × (log 10 φ+p) 4 +b × (log 10 φ+p) 3 +c × (log 10 φ+p) 2 +d × (vector) 10 φ+p) …(Formula 2) However, the coefficients a, b, c, d, and p are a=-0.0923, b=-0.0417, c=0.04331, d=0.3288, and -0.6≦p, respectively.

[0074] The inventors experimentally determined Equation 2, similar to Equation 1. Specifically, in a lighting system combining a halogen lamp and a color filter, the inventors measured the luminous flux of multiple chromaticity coordinates during the transition from the second chromaticity coordinate M2 to the first chromaticity coordinate M1. From these measured luminous flux values ​​and the color difference Δxy between the second chromaticity coordinate M2 and each chromaticity coordinate, the inventors derived Equation 2 as a relational expression that matches or approximates the solid line β2 in Figure 10. The dashed line α4 in Figure 10 shows the change in luminous flux φ when the coefficient p in Equation 2 is zero, and the dashed line α5 in Figure 10 shows the change in luminous flux φ when the coefficient p in Equation 2 is -0.4.

[0075] Here, it is desirable that the lighting system S1 stores in the storage unit 4 of the lighting control device A1 the results calculated by the adjustment unit 3 for the luminous flux ratio of the five types of LEDs for each chromaticity coordinate during the transition from the second chromaticity coordinate M2 to the first chromaticity coordinate M1. When the adjustment unit 3 of the lighting control device A1 receives a control command from the dimmer console C1 instructing it to transition from the second chromaticity coordinate M2 to the first chromaticity coordinate M1, it refers to the calculation results stored in the storage unit 4 and controls the power supply unit 2 so that the luminous flux of each of the first LED 11 to fifth LED 15 at each chromaticity coordinate during the transition satisfies the luminous flux ratio in the calculation results. It is also desirable that the adjustment unit 3 can set the transition time when transitioning from the second chromaticity coordinate M2 to the first chromaticity coordinate M1. The transition time may be included in the control command instructing it to transition from the second chromaticity coordinate M2 to the first chromaticity coordinate M1.

[0076] However, when the lighting system S1 transitions the chromaticity coordinate of the illumination light from the second chromaticity coordinate M2 to the first chromaticity coordinate M1 as described above, it calculates the luminous flux φ1 to φ5 of each of the five types of LEDs (first LED 11, second LED 12, third LED 13, fourth LED 14, fifth LED 15) based on the luminous flux φ that satisfies equation 2, and causes the adjustment unit 3 to control the power supply unit 2. As a result, the lighting system S1 can reduce the luminous flux when the chromaticity coordinate of the illumination light passes through the white region during the transition, as shown by the dashed lines α4 and α5 in Figure 10. Consequently, the lighting system S1 can reduce the sense of incongruity when transitioning light colors by reducing the luminous flux of the white illumination light that appears during the transition, compared to the case where the luminous flux of the illumination light during the transition is changed linearly. However, the lighting system S1 may also allow each chromaticity coordinate during the transition to pass through the region enclosed by the dashed lines α4 and α5 in Figure 10. Alternatively, the chromaticity coordinates of the illuminating light during the transition may lie within the region enclosed by the dashed line α5 and the horizontal axis (color difference Δxy) and vertical axis (luminous flux φ), as shown in Figure 11. In other words, if the chromaticity coordinates of the illuminating light during the transition lie within these regions, they will be perceived as visually almost the same color as when they lie on the solid line β2.

[0077] Therefore, it is preferable for the lighting system S1 to have the adjustment unit 3 calculate the luminous flux φ that satisfies equation 2 by setting the coefficient p in equation 2 to -0.6 or greater or -0.4 or greater. Alternatively, the lighting system S1 may have the adjustment unit 3 calculate the luminous flux φ that satisfies equation 2 by setting the coefficient p in equation 2 to -0.4 or greater and 0.2 or less or -0.4 or greater and 0 or less. By reducing the absolute value of the coefficient p in equation 2 and having the adjustment unit 3 calculate the luminous flux φ, the lighting system S1 can bring the color of the illumination light output from the light source unit 1 closer to the color of light produced by a combination of a halogen lamp and a color filter.

[0078] However, among the chromaticity coordinates during the transition, the area that overlaps with the white region is the range where the color difference Δxy is 0.53 or less, or more specifically, 0.45 or less. Therefore, if the lighting system S1 has the adjustment unit 3 calculate the luminous flux that satisfies equation 2 by setting the coefficient p to -0.4 or more when the color difference Δxy is 0.45 or less or 0.53 or less, the luminous flux of the white illumination light that appears during the transition can be reduced, thereby reducing the sense of incongruity when the light color is transitioned.

[0079] (2-5) Embodiments of lighting methods and programs The illumination method according to the embodiment adjusts the ratio of power supplied to each LED so that the chromaticity coordinate of the illumination light output from the light source unit 1, which has five types of LEDs (first LED 11, second LED 12, third LED 13, fourth LED 14, fifth LED 15), matches the target value. When the chromaticity coordinate of the illumination light transitions from the first chromaticity coordinate M1 to the second chromaticity coordinate M2, the illumination method according to the embodiment calculates the luminous flux φ that satisfies equation 1, and calculates the luminous flux of each of the five types of LEDs based on the calculated luminous flux φ, thereby changing the luminous flux output from the five types of LEDs. However, the first chromaticity coordinate M1 is within the range where the x-coordinate is 0.5 or more and the y-coordinate is 0.4 or more in the chromaticity diagram, and the second chromaticity coordinate M2 is within the range where the x-coordinate is 0.2 or less and the y-coordinate is 0.1 or less. Note that equation 1 is expressed as follows when the color difference is expressed as Δxy and the luminous flux of the illumination light is expressed as φ.

[0080] Δxy = a × (log 10 φ+p)4 +b × (log 10 φ+p) 3 +c × (log 10 φ+p) 2 +d × (vector) 10 φ+p)+e …(Formula 1) However, the coefficients a, b, c, d, e, and p are a=-0.0923, b=0.0417, c=-0.04416, d=-0.3339, e=0.5748, and p≦0.4, respectively.

[0081] Furthermore, in the illumination method according to the embodiment, when transitioning the chromaticity coordinate of the illumination light from the second chromaticity coordinate M2 to the first chromaticity coordinate M1, the luminous flux φ that satisfies equation 2 is calculated, and based on the calculated luminous flux φ, the luminous flux of each of the five types of LEDs is calculated and the luminous flux output from the five types of LEDs is changed. Note that equation 2 is expressed as follows when the color difference is represented as Δxy and the luminous flux of the illumination light is represented as φ.

[0082] Δxy = a × (log 10 φ+p) 4 +b × (log 10 φ+p) 3 +c × (log 10 φ+p) 2 +d × (vector) 10 φ+p) …(Formula 2) However, the coefficients a, b, c, d, and p are a=-0.0923, b=-0.0417, c=0.04331, d=0.3288, and -0.6≦p, respectively.

[0083] According to the illumination method of this embodiment, compared to the case in which the luminous flux of the illumination light during the transition is changed linearly, the luminous flux of the white illumination light that appears during the transition can be reduced, thereby reducing the sense of unnaturalness when the light color is transitioned.

[0084] The program according to the embodiment is a computer program that causes a computer system (a microcontroller in the adjustment unit 3 of the lighting control device A1) to execute the above-described lighting method.

[0085] According to the program of this embodiment, it is possible to reduce the sense of unnaturalness when transitioning between light colors using a general-purpose computer system.

[0086] (3) Modified example of the lighting system according to the embodiment The modified lighting system S1 is characterized in that the processing performed by the adjustment unit 3 of the lighting control device A1 is performed by the dimmer console C1. In Modified Example 1, the adjustment unit 3 is located in the dimmer console C1, not in the lighting control device A1. The modified lighting system S1 has the advantage that the processing burden of lighting control on the lighting control device A1 can be reduced because the adjustment unit 3 is located in the dimmer console C1.

[0087] (4) Summary A lighting system (S1) according to a first aspect of this disclosure includes a light source unit (1) that outputs illumination light, a power supply unit (2) that supplies power to the light source unit (1), and an adjustment unit (3) that controls the power supply unit (2) to adjust the power supplied to the light source unit (1). The light source unit (1) has multiple types of light-emitting elements (first LED 11, second LED 12, third LED 13, fourth LED 14, fifth LED 15) with different light colors. The power supply unit (2) is configured to supply power separately to each of the multiple types of light-emitting elements of the same type. The adjustment unit (3) adjusts the ratio of the amount of power supplied to the multiple types of light-emitting elements so that the chromaticity coordinate of the illumination light output from the light source unit (1) matches a target value. The adjustment unit (3) calculates a luminous flux (φ) that satisfies the following equation 1 when transitioning the chromaticity coordinate of the illumination light from the first chromaticity coordinate (M1) to the second chromaticity coordinate (M2), and controls the power supply unit (2) by calculating the luminous flux of each of the multiple types of light-emitting elements based on the calculated luminous flux (φ). The first chromaticity coordinate (M1) is within the range where the x-coordinate in the chromaticity diagram is 0.5 or more and the y-coordinate is 0.4 or more. The second chromaticity coordinate (M2) is within the range where the x-coordinate is 0.2 or less and the y-coordinate is 0.1 or less. Equation 1 is expressed when Δxy represents the color difference between the first chromaticity coordinate (M1) and the intermediate chromaticity coordinates (M3~M11), and φ represents the luminous flux of the illumination light. Δxy = a × (log 10 φ+p) 4 +b × (log 10 φ+p)3 +c × (log 10 φ+p) 2 +d × (vector) 10 φ+p)+e …(Formula 1) (However, the coefficients a, b, c, d, e, and p are a=-0.0923, b=0.0417, c=-0.04416, d=-0.3339, e=0.5748, and p≦0.4, respectively.) That is the case.

[0088] The first embodiment of the lighting system (S1) can reduce the luminous flux when the chromaticity coordinate of the illuminating light passes through the white region during the transition from the first chromaticity coordinate (M1) to the second chromaticity coordinate (M2). As a result, the first embodiment of the lighting system (S1) can reduce the sense of incongruity when transitioning between light colors by reducing the luminous flux of the white illuminating light that appears during the transition, compared to the case where the luminous flux of the illuminating light during the transition is changed linearly.

[0089] A lighting system (S1) according to a second aspect of this disclosure can be realized by combining it with the first aspect. In the lighting system (S1) according to the second aspect, it is preferable that the adjustment unit (3) calculates a luminous flux that satisfies equation 1 by setting the coefficient p to 0.2 or less, calculates the luminous flux of each of the multiple types of light-emitting elements based on the calculated luminous flux, and controls the power supply unit (2).

[0090] The lighting system (S1) according to the second embodiment can further reduce the sense of unnaturalness when transitioning between light colors.

[0091] A lighting system (S1) according to a third aspect of this disclosure can be realized by combining it with the second aspect. In the lighting system (S1) according to the third aspect, it is preferable that the adjustment unit (3) calculates a luminous flux that satisfies equation 1 by setting the coefficient p to 0.2 or less when the color difference (Δxy) is 0.1 or more, calculates the luminous flux of each of the multiple types of light-emitting elements based on the calculated luminous flux, and controls the power supply unit (2).

[0092] The lighting system (S1) according to the third embodiment can further reduce the sense of unnaturalness when transitioning between light colors.

[0093] A lighting system (S1) according to a fourth aspect of this disclosure can be realized by combining it with the first aspect. In the lighting system (S1) according to the fourth aspect, it is preferable that the adjustment unit (3) calculates a luminous flux that satisfies equation 1 by setting the coefficient p to -0.4 or more and 0.4 or less, and then calculates the luminous flux of each of the multiple types of light-emitting elements based on the calculated luminous flux and controls the power supply unit (2).

[0094] The lighting system (S1) according to the fourth embodiment can further reduce the sense of unnaturalness when transitioning between light colors.

[0095] A lighting system (S1) according to a fifth aspect of this disclosure can be realized by combining it with a fourth aspect. In the lighting system (S1) according to the fifth aspect, it is preferable that the adjustment unit (3) calculates a luminous flux that satisfies equation 1 by setting the coefficient p to be -0.2 or greater and 0.2 or less, and then calculates the luminous flux of each of the multiple types of light-emitting elements based on the calculated luminous flux and controls the power supply unit (2).

[0096] The fifth aspect of the lighting system (S1) can further reduce the sense of unnaturalness when transitioning between light colors.

[0097] A lighting system (S1) according to a sixth aspect of this disclosure can be realized in combination with any of the first to fifth aspects. Preferably, the lighting system (S1) according to the sixth aspect further comprises a storage unit (4) that stores the luminous flux (φ) calculated by the adjustment unit (3) in correspondence with the color difference (Δxy).

[0098] The lighting system (S1) according to the sixth embodiment can reduce the processing burden on the adjustment unit (3) compared to the case in which the adjustment unit (3) calculates the luminous flux (φ) each time the chromaticity coordinate of the illumination light is transitioned from the first chromaticity coordinate (M1) to the second chromaticity coordinate (M2).

[0099] The lighting system (S1) according to the seventh aspect of the present disclosure can be realized by a combination with any of the first to sixth aspects. In the lighting system (S1) according to the seventh aspect, it is preferable that the adjustment unit (3) can set the transition time when transitioning from the first chromaticity coordinate (M1) to the second chromaticity coordinate (M2).

[0100] The lighting system (S1) according to the seventh aspect can improve usability because the transition time can be changed.

[0101] The lighting system (S1) according to the eighth aspect of the present disclosure includes a light source unit (1) that outputs illumination light, a power supply unit (2) that supplies power to the light source unit (1), and an adjustment unit (3) that controls the power supply unit (2) to adjust the power supplied to the light source unit (1). The light source unit (1) has a plurality of types of light-emitting elements (first LED11, second LED12, third LED13, fourth LED14, fifth LED15) with different light colors from each other. The power supply unit (2) is configured to be able to supply power separately to the same type of light-emitting elements among the plurality of types of light-emitting elements. The adjustment unit (3) adjusts the ratio of the power supply amounts to the plurality of types of light-emitting elements so that the chromaticity coordinate of the illumination light output from the light source unit (1) matches the target value. When transitioning the chromaticity coordinate of the illumination light from the second chromaticity coordinate (M2) to the first chromaticity coordinate (M1), the adjustment unit (3) calculates a luminous flux (φ) that satisfies the following formula 2, and calculates the luminous flux of each of the plurality of types of light-emitting elements based on the calculated luminous flux (φ) to control the power supply unit (2). The second chromaticity coordinate (M2) exists within a range where the x coordinate in the chromaticity diagram is 0.2 or less and the y coordinate is 0.1 or less. The first chromaticity coordinate (M1) exists within a range where the x coordinate is 0.5 or more and the y coordinate is 0.4 or more. In formula 2, when the color difference between the second chromaticity coordinate (M2) and the chromaticity coordinate (M11 to M3) during the transition is represented as Δxy, and the luminous flux of the illumination light is represented as φ Δxy = a×(log 10 φ + p) 4 + b×(log 10 φ + p) 3 + c×(log 10 φ + p) 2 + d×(log 10 φ + p) …(Formula 2) (However, the coefficients a, b, c, d, and p are a=-0.0923, b=-0.0417, c=0.04331, d=0.3288, and -0.6≦p, respectively.) That is the case.

[0102] The lighting system (S1) according to the eighth embodiment can reduce the luminous flux when the chromaticity coordinate of the illumination light passes through the white region during the transition from the second chromaticity coordinate (M2) to the first chromaticity coordinate (M1). As a result, the lighting system (S1) according to the eighth embodiment can reduce the sense of incongruity when transitioning light colors by reducing the luminous flux of the white illumination light that appears during the transition, compared to the case in which the luminous flux of the illumination light during the transition is changed linearly.

[0103] A lighting system (S1) according to the ninth aspect of this disclosure can be realized by combining it with the eighth aspect. In the lighting system (S1) according to the ninth aspect, it is preferable that the adjustment unit (3) calculates a luminous flux that satisfies equation 2 by setting the coefficient p to -0.4 or more, and controls the power supply unit (2) by calculating the luminous flux of each of the multiple types of light-emitting elements based on the calculated luminous flux.

[0104] The lighting system (S1) according to the ninth embodiment can further reduce the sense of incongruity when transitioning between light colors.

[0105] A lighting system (S1) according to a tenth aspect of this disclosure can be realized by combining it with a ninth aspect. In the lighting system (S1) according to the tenth aspect, it is preferable that the adjustment unit (3) calculates a luminous flux that satisfies equation 2 by setting the coefficient p to -0.4 or more when the color difference (Δxy) is 0.53 or less, calculates the luminous flux of each of the multiple types of light-emitting elements based on the calculated luminous flux, and controls the power supply unit (2).

[0106] The lighting system (S1) according to the tenth embodiment can further reduce the sense of unnaturalness when transitioning between light colors.

[0107] An 11th aspect of the present disclosure, the lighting system (S1), can be realized by combining it with the 10th aspect. In the 11th aspect of the lighting system (S1), it is preferable that the adjustment unit (3) calculates a luminous flux that satisfies equation 2 by setting the coefficient p to -0.4 or more when the color difference (Δxy) is 0.45 or less, calculates the luminous flux of each of the multiple types of light-emitting elements based on the calculated luminous flux, and controls the power supply unit (2).

[0108] The lighting system (S1) according to the eleventh embodiment can further reduce the sense of unnaturalness when transitioning between light colors.

[0109] A lighting system (S1) according to a twelfth aspect of this disclosure can be realized by combining it with an eighth aspect. In the lighting system (S1) according to the twelfth aspect, it is preferable that the adjustment unit (3) calculates a luminous flux that satisfies equation 2 by setting the coefficient p to -0.4 or more and 0.2 or less, and then calculates the luminous flux of each of the multiple types of light-emitting elements based on the calculated luminous flux and controls the power supply unit (2).

[0110] The lighting system (S1) according to the twelfth embodiment can further reduce the sense of unnaturalness when transitioning between light colors.

[0111] A lighting system (S1) according to a thirteenth aspect of this disclosure can be realized by combining it with a twelfth aspect. In the lighting system (S1) according to the thirteenth aspect, it is preferable that the adjustment unit (3) calculates a luminous flux that satisfies equation 2 by setting the coefficient p to -0.4 or greater and 0 or less, and then calculates the luminous flux of each of the multiple types of light-emitting elements based on the calculated luminous flux and controls the power supply unit (2).

[0112] The lighting system (S1) according to the 13th embodiment can further reduce the sense of unnaturalness when transitioning between light colors.

[0113] A lighting system (S1) according to a 14th aspect of this disclosure can be realized in combination with any of the 8th to 13th aspects. Preferably, the lighting system (S1) according to the 14th aspect further comprises a storage unit (4) that stores the luminous flux calculated by the adjustment unit (3) in correspondence with the color difference (Δxy).

[0114] The 14th embodiment of the lighting system (S1) can reduce the processing burden on the adjustment unit (3) compared to the case where the adjustment unit (3) calculates the luminous flux (φ) each time the chromaticity coordinate of the illumination light is transitioned from the second chromaticity coordinate (M2) to the first chromaticity coordinate (M1).

[0115] A lighting system (S1) according to the 15th aspect of this disclosure can be realized in combination with any of the 8th to 14th aspects. In the lighting system (S1) according to the 15th aspect, it is preferable that the adjustment unit (3) can set the transition time when transitioning from a second chromaticity coordinate (M2) to a first chromaticity coordinate (M1).

[0116] The lighting system (S1) according to the 15th embodiment can improve usability because the transition time can be changed.

[0117] The illumination method according to the 16th aspect of this disclosure adjusts the ratio of power supplied to multiple types of light-emitting elements so that the chromaticity coordinate of the illumination light output from a light source unit (1) having multiple types of light-emitting elements with different light colors matches a target value. The illumination method according to the 16th aspect calculates the luminous flux that satisfies equation 1 when transitioning the chromaticity coordinate of the illumination light from a first chromaticity coordinate (M1) to a second chromaticity coordinate (M2), and calculates the luminous flux of each of the multiple types of light-emitting elements based on the calculated luminous flux to change the luminous flux output from the multiple types of light-emitting elements. The first chromaticity coordinate (M1) is within the range where the x-coordinate in the chromaticity diagram is 0.5 or more and the y-coordinate is 0.4 or more. The second chromaticity coordinate (M2) is within the range where the x-coordinate is 0.2 or less and the y-coordinate is 0.1 or less. Equation 1 is expressed when the color difference between the first chromaticity coordinate (M1) and the intermediate chromaticity coordinates (M3 to M11) is expressed as Δxy, and the luminous flux of the illumination light is expressed as φ. Δxy = a×(log 10 φ + p) 4 + b×(log 10 φ + p) 3 + c×(log 10 φ + p) 2 + d×(log 10 φ + p) + e …(Equation 1) (However, the coefficients a, b, c, d, e, and p are a = -0.0923, b = 0.0417, c = -0.04416, d = -0.3339, e = 0.5748, and p ≤ 0.4, respectively.) That is.

[0118] When the chromaticity coordinates of the illumination light are transitioned from the first chromaticity coordinates (M1) to the second chromaticity coordinates (M2) in the illumination method according to the 16th aspect, by reducing the luminous flux of the white illumination light that appears during the transition compared to the case where the luminous flux of the illumination light during the transition is linearly changed, it is possible to reduce the sense of incongruity when changing the light color.

[0119] In the illumination method according to the 17th aspect of the present disclosure, the ratio of the power supply amounts to the plurality of types of light emitting elements is adjusted so that the chromaticity coordinates of the illumination light output from the light source unit (1) having a plurality of types of light emitting elements with different light colors match the target value. When transitioning the chromaticity coordinates of the illumination light from the first chromaticity coordinates (M1) to the second chromaticity coordinates (M2) in the illumination method according to the 17th aspect, the luminous flux satisfying Equation 2 is calculated, and based on the calculated luminous flux, the luminous flux of each of the plurality of types of light emitting elements is calculated to change the luminous flux output from the plurality of types of light emitting elements. The first chromaticity coordinates (M1) exist within a range where the x coordinate in the chromaticity diagram is 0.5 or more and the y coordinate is 0.4 or more. The second chromaticity coordinates (M2) exist within a range where the x coordinate is 0.2 or less and the y coordinate is 0.1 or less. Equation 2 represents the color difference between the second chromaticity coordinates (M2) and the chromaticity coordinates (M11 to M3) during the transition as Δxy, and when the luminous flux of the illumination light is represented as φ Δxy = a×(log 10 φ + p) 4 + b×(log 10 φ + p) 3 + c×(log 10 φ + p) 2+d × (vector) 10 φ+p) …(Formula 2) (However, the coefficients a, b, c, d, and p are a=-0.0923, b=-0.0417, c=0.04331, d=0.3288, and -0.6≦p, respectively.) That is the case.

[0120] The illumination method according to the 17th embodiment reduces the sense of incongruity when transitioning between light colors by reducing the luminous flux of white illumination light that appears during the transition, compared to the case where the luminous flux of illumination light is changed linearly during the transition when the chromaticity coordinate of the illumination light is transitioned from the second chromaticity coordinate (M2) to the first chromaticity coordinate (M1).

[0121] A program relating to the 18th aspect of this disclosure causes a computer system to execute an illumination method relating to the 16th or 17th aspect.

[0122] The program according to the 18th embodiment can reduce the sense of unnaturalness when transitioning between light colors using a general-purpose computer system. [Explanation of symbols]

[0123] S1 Lighting System M1 First chromaticity coordinate M2 is the second chromaticity coordinate. Δxy color difference φ Luminous flux 1 Light source section 2 Power supply section 3 Adjustment part 4 Storage section 11. First LED (light-emitting element) 12. Second LED (light-emitting element) 13. Third LED (light-emitting element) 14. 4th LED (light-emitting element) 15. Fifth LED (light-emitting element)

Claims

1. A light source unit that outputs illumination light, A power supply unit that supplies power to the light source unit, An adjustment unit that controls the power supply unit to adjust the power supplied to the light source unit, Equipped with, The light source unit has multiple types of light-emitting elements that have different light colors from each other. The power supply unit is configured to be able to supply power separately to each of the multiple types of light-emitting elements of the same type. The adjustment unit adjusts the ratio of the amount of power supplied to the multiple types of light-emitting elements so that the chromaticity coordinates of the illumination light output from the light source unit match the target value. When the adjustment unit transitions the chromaticity coordinates of the illumination light from a first chromaticity coordinate where the x-coordinate is in the range of 0.5 or more and the y-coordinate is in the range of 0.4 or more in the chromaticity diagram, to a second chromaticity coordinate where the x-coordinate is in the range of 0.2 or less and the y-coordinate is in the range of 0.1 or less, the color difference between the first chromaticity coordinate and the chromaticity coordinate during the transition is expressed as Δxy, and the luminous flux of the illumination light is expressed as φ, then the following equation 1 Δxy = a×(log 10 φ + p) 4 + b×(log 10 φ + p) 3 + c×(log 10 φ + p) 2 + d×(log 10 φ + p) + e … (Equation 1) (However, the coefficients a, b, c, d, e, and p are a=-0.0923, b=0.0417, c=-0.04416, d=-0.3339, e=0.5748, and p≦0.4, respectively.) The system calculates the luminous flux required to achieve the condition, and based on the calculated luminous flux, it calculates the luminous flux for each of the multiple types of light-emitting elements and controls the power supply unit. Lighting system.

2. The adjustment unit calculates the luminous flux that satisfies equation 1 by setting the coefficient p to 0.2 or less, and calculates the luminous flux of each of the multiple types of light-emitting elements based on the calculated luminous flux, and controls the power supply unit. The lighting system according to claim 1.

3. The adjustment unit calculates the luminous flux that satisfies formula 1 by setting the coefficient p to 0.2 or less when the color difference is 0.1 or more, calculates the luminous flux of each of the multiple types of light-emitting elements based on the calculated luminous flux, and controls the power supply unit. The lighting system according to claim 2.

4. The adjustment unit calculates the luminous flux that satisfies equation 1 by setting the coefficient p to -0.4 or greater and 0.4 or less, and calculates the luminous flux of each of the multiple types of light-emitting elements based on the calculated luminous flux and controls the power supply unit. The lighting system according to claim 1.

5. The adjustment unit calculates the luminous flux that satisfies equation 1 by setting the coefficient p to -0.2 or more and 0.2 or less, calculates the luminous flux of each of the multiple types of light-emitting elements based on the calculated luminous flux, and controls the power supply unit. The lighting system according to claim 4.

6. The system further includes a storage unit that stores the luminous flux calculated by the adjustment unit in correspondence with the color difference. The lighting system according to any one of claims 1 to 5.

7. The adjustment unit can set the transition time when transitioning from the first chromaticity coordinate to the second chromaticity coordinate. The lighting system according to any one of claims 1 to 5.

8. A light source unit that outputs illumination light, A power supply unit that supplies power to the light source unit, An adjustment unit that controls the power supply unit to adjust the power supplied to the light source unit, Equipped with, The light source unit has multiple types of light-emitting elements that have different light colors from each other. The power supply unit is configured to be able to supply power separately to each of the multiple types of light-emitting elements of the same type. The adjustment unit adjusts the ratio of the amount of power supplied to the multiple types of light-emitting elements so that the chromaticity coordinates of the illumination light output from the light source unit match the target value. When the adjustment unit transitions the chromaticity coordinates of the illumination light from a second chromaticity coordinate where the x-coordinate is within the range of 0.2 or less and the y-coordinate is within the range of 0.1 or less in the chromaticity diagram, to a first chromaticity coordinate where the x-coordinate is within the range of 0.5 or more and the y-coordinate is within the range of 0.4 or more, the color difference between the second chromaticity coordinate and the chromaticity coordinate during the transition is expressed as Δxy, and the luminous flux of the illumination light is expressed as φ, then the following equation 2 Δxy = a×(log 10 φ + p) 4 + b×(log 10 φ + p) 3 + c×(log 10 φ + p) 2 + d×(log 10 φ + p) … (Equation 2) (However, the coefficients a, b, c, d, and p are a=-0.0923, b=-0.0417, c=0.04331, d=0.3288, and -0.6≦p, respectively.) The system calculates the luminous flux required to achieve the condition, and based on the calculated luminous flux, it calculates the luminous flux for each of the multiple types of light-emitting elements and controls the power supply unit. Lighting system.

9. The adjustment unit calculates the luminous flux that satisfies equation 2 by setting the coefficient p to -0.4 or more, and calculates the luminous flux of each of the multiple types of light-emitting elements based on the calculated luminous flux, and controls the power supply unit. The lighting system according to claim 8.

10. The adjustment unit calculates the luminous flux that satisfies equation 2 by setting the coefficient p to -0.4 or more when the color difference is 0.53 or less, calculates the luminous flux of each of the multiple types of light-emitting elements based on the calculated luminous flux, and controls the power supply unit. The lighting system according to claim 9.

11. The adjustment unit calculates the luminous flux that satisfies equation 2 by setting the coefficient p to -0.4 or more when the color difference is 0.45 or less, calculates the luminous flux of each of the multiple types of light-emitting elements based on the calculated luminous flux, and controls the power supply unit. The lighting system according to claim 10.

12. The adjustment unit calculates the luminous flux that satisfies equation 2 by setting the coefficient p to -0.4 or greater and 0.2 or less, and calculates the luminous flux of each of the multiple types of light-emitting elements based on the calculated luminous flux and controls the power supply unit. The lighting system according to claim 8.

13. The adjustment unit calculates the luminous flux that satisfies equation 2 by setting the coefficient p to -0.4 or greater and 0 or less, and calculates the luminous flux of each of the multiple types of light-emitting elements based on the calculated luminous flux and controls the power supply unit. The lighting system according to claim 12.

14. The system further includes a storage unit that stores the luminous flux calculated by the adjustment unit in correspondence with the color difference. The lighting system according to any one of claims 8-13.

15. The adjustment unit can set the transition time when transitioning from the second chromaticity coordinate to the first chromaticity coordinate. The lighting system according to any one of claims 8-13.

16. When adjusting the ratio of power supplied to multiple types of light-emitting elements so that the chromaticity coordinates of the illumination light output from a light source having multiple types of light-emitting elements with different light colors match a target value, and transitioning the chromaticity coordinates of the illumination light from a first chromaticity coordinate where the x-coordinate is in the range of 0.5 or more and the y-coordinate is in the range of 0.4 or more in the chromaticity diagram to a second chromaticity coordinate where the x-coordinate is in the range of 0.2 or less and the y-coordinate is in the range of 0.1 or less, the color difference between the first chromaticity coordinate and the chromaticity coordinate during the transition is expressed as Δxy, and the luminous flux of the illumination light is expressed as φ, then the following equation 1 Δxy = a×(log 10 φ + p) 4 + b×(log 10 φ + p) 3 + c×(log 10 φ + p) 2 + d×(log 10 φ + p)+ e … (Equation 1) (However, the coefficients a, b, c, d, e, and p are a=-0.0923, b=0.0417, c=-0.04416, d=-0.3339, e=0.5748, and p≦0.4, respectively.) The luminous flux that satisfies the condition is calculated, and based on the calculated luminous flux, the luminous flux of each of the multiple types of light-emitting elements is calculated and the luminous flux output from the multiple types of light-emitting elements is changed. lighting method.

17. When adjusting the ratio of power supplied to multiple types of light-emitting elements so that the chromaticity coordinates of the illumination light output from a light source having multiple types of light-emitting elements with different light colors match a target value, and transitioning the chromaticity coordinates of the illumination light from a second chromaticity coordinate where the x-coordinate is within the range of 0.2 or less and the y-coordinate is within the range of 0.1 or less in the chromaticity diagram to a first chromaticity coordinate where the x-coordinate is within the range of 0.5 or more and the y-coordinate is within the range of 0.4 or more, the color difference between the second chromaticity coordinate and the chromaticity coordinate during the transition is expressed as Δxy, and the luminous flux of the illumination light is expressed as φ, then the following equation 2 Δxy = a×(log 10 φ + p) 4 + b×(log 10 φ + p) 3 + c×(log 10 φ + p) 2 + d×(log 10 φ + p) … (Equation 2) (However, the coefficients a, b, c, d, and p are a=-0.0923, b=-0.0417, c=0.04331, d=0.3288, and -0.6≦p, respectively.) The luminous flux that satisfies the condition is calculated, and based on the calculated luminous flux, the luminous flux of each of the multiple types of light-emitting elements is calculated and the luminous flux output from the multiple types of light-emitting elements is changed. lighting method.

18. The computer system is made to perform the lighting method according to claim 16 or 17. program.

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