Lighting control device and lighting device

Abstract

The objective of this disclosure is to suppress changes in light output caused by variations in the output characteristics of LEDs. [Solution] The lighting control device A1 comprises a current output unit 10 that outputs current to one or more LEDs 40, a storage unit 20, and a control unit 21. The storage unit 20 stores characteristic data and current correction data related to the output characteristics of the LEDs 40. The control unit 21 sets a target value for the current based on a control command input from an external source and controls the current output unit 10 to make the current match the target value. The control unit 21 refers to the characteristic data and correction data and corrects the target value for the control command.

Description

Technical Field

[0001] The present disclosure relates to a lighting control device and a lighting device, and more particularly to a lighting control device for dimming a light source and a lighting device including the lighting control device.

Background Art

[0002] As a conventional example, an LED lighting device (lighting device) described in Patent Document 1 is exemplified. The LED lighting device described in Patent Document 1 (hereinafter referred to as a conventional example) includes an LED light source unit including a plurality of light emitting diodes, a power source for supplying power for lighting the light emitting diodes of the LED light source unit, and a power input from the power source. And a dimming control circuit that dims and lights the light emitting diodes so that the light output of the light emitting diodes of the LED light source unit approximates the light output of an incandescent bulb based on a dimming signal.

[0003] With the above configuration, the conventional example can obtain the same light output change as that of an incandescent bulb when the light emitting diodes as the light source are dimmed and controlled based on a dimming signal for an incandescent bulb.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] By the way, LEDs generally tend to have variations in output characteristics (relationship between input current and light output). That is, when the same magnitude of input current is applied to a plurality of LEDs, a significant difference may occur in the light output of each of the plurality of LEDs.

[0006] However, since the above conventional example does not consider variations in the output characteristics of each of the plurality of LEDs in the LED light source unit, there is a possibility that variations may occur in the light output of the LED light source unit with respect to a dimming signal.

[0007] The purpose of this disclosure is to provide a lighting control device and a lighting device that can suppress changes in light output caused by variations in the output characteristics of LEDs. [Means for solving the problem]

[0008] A lighting control device according to one aspect of the present disclosure comprises a current output unit that outputs current to one or more LEDs, a storage unit, and a control unit. The storage unit stores characteristic data relating to the output characteristics of the LEDs and correction data for the current. The control unit sets a target value for the current based on a control command input from an external source and controls the current output unit to make the current match the target value. The control unit corrects the target value for the control command by referring to the characteristic data and the correction data.

[0009] A lighting device according to one aspect of this disclosure comprises a light source including one or more LEDs and the lighting control device.

[0010] A lighting device according to one aspect of the present disclosure comprises a light source including a plurality of LEDs of different colors, and a lighting control device. The lighting control device includes a plurality of current output units that correspond one-to-one with the plurality of LEDs of different colors and output the current to the corresponding LEDs. The storage unit stores characteristic data and correction data for each of the plurality of LEDs. The control unit sets the target value for each of the plurality of LEDs based on the control command, and corrects the target value for the control command by referring to the characteristic data and correction data for each of the plurality of LEDs. [Effects of the Invention]

[0011] The lighting control device and lighting device disclosed herein have the effect of suppressing changes in light output caused by variations in the output characteristics of LEDs. [Brief explanation of the drawing]

[0012] [Figure 1]Figure 1 is a block diagram of a lighting control device according to an embodiment of the present disclosure. [Figure 2] Figure 2 shows the current-luminous flux characteristics of the LED in the same lighting control device. [Figure 3] Figure 3 is a perspective view of a lighting device according to an embodiment of this disclosure. [Figure 4] Figure 4 is a circuit block diagram of the same lighting control device. [Figure 5] Figure 5 is a chromaticity diagram obtained by blotting the chromaticity coordinates of the LEDs in the same lighting device. [Figure 6] Figure 6 shows the relationship between the total dimming value and the correction value in the same lighting control device. [Modes for carrying out the invention]

[0013] Hereinafter, the lighting control device A1 and lighting device B1 according to embodiments of this disclosure will be described in detail with reference to the drawings. However, the figures described in the following embodiments are schematic diagrams, and the ratios of the size and thickness of each component do not necessarily reflect the actual dimensional ratios. Furthermore, 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.

[0014] (1) Overview The lighting control device A1 according to this embodiment includes a current output unit 10 that outputs current to one or more LEDs 40, a storage unit 20, and a control unit 21 (see Figure 1).

[0015] The current output section 10 includes a DC / DC converter, such as a buck converter (step-down chopper circuit). The DC / DC converter in the current output section 10 allows for adjustment (increase or decrease) of the output current.

[0016] The control unit 21 sets a target value for the output current of the current output unit 10 based on control commands input from an external source. The control unit 21 also controls the current output unit 10 to match the target value for the output current.

[0017] The memory unit 20 stores characteristic data regarding the output characteristics of the LED 40 and correction data for the current (the output current of the current output unit 10).

[0018] The current-light flux characteristic of the LED 40 is preferably directly proportional (see the dashed line X1 in FIG. 2). However, in reality, the proportionality coefficient is not constant (directly proportional). For example, the proportionality coefficient may change while the current value increases from zero to the rated value (see the solid line X2 in FIG. 2). That is, the characteristic data is the correction coefficient α for making the relationship between the current flowing through the LED 40 and the light flux emitted from the LED 40 approach direct proportionality.

[0019] Also, the correction data for the current is a correction coefficient for making the relationship between the dimming level indicated by the control command and the output current of the current output unit 10 approach direct proportionality.

[0020] The control unit 21 refers to the characteristic data and the correction data and corrects the target value of the output current for the control command.

[0021] Thus, since the lighting control device A1 according to the embodiment includes the control unit 21 that refers to the characteristic data and the correction data and corrects the target value for the control command, by making the change in the current (the output current of the current output unit 10) for the control command approach direct proportionality, the change in the light output (light flux) caused by the variation in the output characteristics of the LED 40 can be suppressed.

[0022] Also, the lighting device B1 according to the embodiment includes a light source (light source unit 4) including one or more LEDs 40 and the lighting control device A1 according to the embodiment (see FIG. 3).

[0023] Since the lighting device B1 according to the embodiment includes the lighting control device A1 according to the embodiment, the change in the light output (light flux) caused by the variation in the output characteristics of the LED 40 can be suppressed.

[0024] (2) Details Next, the lighting control device A1 (hereinafter abbreviated as lighting control device A1) and the lighting device B1 (hereinafter abbreviated as lighting device B1) according to the embodiment will be described in more detail with reference to the drawings.

[0025] (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). However, lighting device B1 may be a lighting device other than a lower cyclorama light, such as an upper cyclorama light, border light, or floodlight.

[0026] The lighting device B1 comprises a light source unit 4 and a lighting control device A1. The lighting device B1 also comprises a pair of support parts and a pair of connecting parts 5 that support the light source unit 4 relative to the lighting control device A1.

[0027] The light source unit 4 includes multiple LED modules, multiple lens blocks, a panel 42, and a second housing 41 (see Figure 3).

[0028] Each of the multiple LED modules is constructed by mounting six different types of LEDs 40, each with a different light color, onto a rectangular circuit board. The six types of LEDs 40 have light colors of red, green, blue, amber, sky blue, and emerald green. In the following description, when distinguishing between the LEDs 40 of each color, the red LED 40 may be referred to as the 1st LED 40R, the green LED 40 as the 2nd LED 40G, the blue LED 40 as the 3rd LED 40B, the amber LED 40 as the 4th LED 40A, the sky blue LED 40 as the 5th LED 40SB, and the emerald green LED 40 as the 6th LED 40EG. Multiple units of each of the six types of LEDs 40 are mounted on the surface of the circuit board. However, the types (light colors) and numbers of LEDs 40 are merely examples.

[0029] Among the multiple LEDs 40, LEDs 40 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 10 (first current output unit 11 to sixth current output unit 16) of the lighting control device A1 via multiple connectors mounted on the circuit board, as will be described later (see Figure 4).

[0030] Each of the multiple lens blocks has multiple lens sections. The multiple lens sections control the light distribution of the light emitted from the multiple LEDs 40. The multiple lens sections are integrally formed from a translucent synthetic resin material such as polycarbonate resin or acrylic resin.

[0031] Panel 42 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 42 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, each panel 42 may be configured to diffuse transmitted light by applying a textured or uneven surface to its front or back surface.

[0032] The second housing 41 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 41 with the sides on which the LEDs 40 are mounted facing the front of the second housing 41. Multiple lens blocks are also housed inside the second housing 41 so as to cover the front of the multiple LED modules. The opening on the front of the second housing 41 is covered by a panel 42.

[0033] The light source unit 4 is supported by a pair of support parts in the first housing 3 of the lighting control device A1. Each of the support parts is made up of a hinge. In other words, the light source unit 4 is rotatably supported relative to the first housing 3 by the pair of support parts (hinges).

[0034] Furthermore, the light source unit 4 is mechanically connected to the first housing 3 by a pair of connecting parts 5. Each of the pair of connecting parts 5 is formed from an arc-shaped metal plate. The pair of connecting parts 5 are mechanically connected to the second housing 41 of the light source unit 4 at one end in the circumferential direction and are screwed to the first housing 3 at the other end in the circumferential direction. However, the pair of connecting parts 5 are provided so that a plurality of screw insertion holes 50 are arranged in two rows in the circumferential direction.

[0035] Therefore, the light source unit 4 is rotatably supported by a pair of support parts, and can be fixed at any rotation angle by being screwed to the first housing 3 with thumb screws 51 inserted through any of the screw insertion holes 50.

[0036] (2-2) Lighting control device The lighting control device A1 comprises six current output units 10, each corresponding to one of six types of LEDs 40, a storage unit 20, and a control unit 21 (see Figure 4). Furthermore, the lighting control device A1 includes an AC / DC converter 17, a communication unit 22, an input receiving unit 23, and a display unit 24. Note that in Figure 4, only one of each of the six types of LEDs 40 (first LED 40R, second LED 40G, third LED 40B, fourth LED 40A, fifth LED 40SB, and sixth LED 40EG) is shown.

[0037] The six current output units 10 include a first current output unit 11, a second current output unit 12, a third current output unit 13, a fourth current output unit 14, a fifth current output unit 15, and a sixth current output unit 16. The first current output unit 11 outputs current to the first LED 40R. The second current output unit 12 outputs current to the second LED 40G. The third current output unit 13 outputs current to the third LED 40B. The fourth current output unit 14 outputs current to the fourth LED 40A. The fifth current output unit 15 outputs current to the fifth LED 40SB. The sixth current output unit 16 outputs current to the sixth LED 40EG. However, the six current output units 10 have a common circuit configuration. Each current output unit 10 has a DC / DC converter such as a buck converter (step-down chopper circuit). The DC / DC converter of each current output unit 10 can adjust (increase or decrease) the output current.

[0038] The AC / DC converter 17 is configured to convert the AC voltage supplied from an external power source P1 (for example, an AC power source with an effective value of 100V) into a DC voltage and supply it to each current output unit 10. The AC / DC converter 17 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 17 is electrically connected in parallel to the input terminals of the six current output units 10.

[0039] The communication unit 22 is configured to communicate with an external lighting console C1 via a communication cable. The communication unit 22 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 22 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 22 transmits the control data contained in the DMX signals received from the lighting console C1 to the control unit 21, for example, via serial communication such as UART (Universal Asynchronous Receiver / Transmitter).

[0040] The control unit 21 mainly consists of a microcontroller. The microcontroller of the control unit 21 acquires control data from the communication unit 22 by performing serial communication with the communication unit 22. The control unit 21 executes a lighting control program using the microcontroller, and controls each current output unit 10 in accordance with the control commands (DMX signals) received from the dimming console C1 via the communication unit 22, thereby performing functions such as blinking, dimming, and color adjustment of the light source unit 4 (multiple LEDs 40).

[0041] By the way, there are two types of dimming methods in which the control unit 21 dims multiple LEDs 40 by increasing or decreasing the output current of each current output unit 10. One is a dimming method that changes the magnitude of the current that flows continuously through the LEDs 40, and is usually called a DC dimming method. The other is a dimming method that periodically turns the power supply to the LEDs 40 on and off and changes the ratio of the power supply period (on duty cycle), and is usually called a burst dimming method.

[0042] 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 LED40 being 100%.

[0043] Therefore, the control unit 21 controls the current output unit 10 using a burst dimming method when the dimming level is below a threshold, and controls the current output unit 10 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%.

[0044] Furthermore, the six different colors of light emitted from the six types of LEDs 40 are mixed during the process of light distribution control by the lens block and transmission through the panel 42. In other words, the color of the light emitted from the light source unit 4 is determined by the ratio of the dimming levels of the six types of LEDs 40.

[0045] Here, the chromaticity coordinates of the six types of LEDs 40 are shown in the chromaticity diagram of Figure 5. Figure 5 is the xy chromaticity diagram of the XYZ color system. In Figure 5, the chromaticity coordinates W1, W2, W3, W4, W5, and W6 represent the chromaticity coordinate W1 of the first LED 40R, W2 of the second LED 40G, W3 of the third LED 40B, W4 of the fourth LED 40A, W5 of the fifth LED 40SB, and W6 of the sixth LED 40EG, respectively. In other words, the control unit 21 can realize any light color with chromaticity coordinates in a hexagonal region with the six chromaticity coordinates W1, W4, W2, W6, W5, and W3 as vertices, according to the ratio of the dimming levels of the six types of LEDs 40.

[0046] Furthermore, the control unit 21 can adjust the dimming level of each type of LED 40 while maintaining the ratio of the dimming levels of the six types of LEDs 40, thereby enabling dimming of light of any desired color.

[0047] The input receiving unit 23 has multiple tact switches (push-button switches) (see Figure 3). The input receiving unit 23 receives operation input from the operator according to the on / off state of these tact switches. The operation input received by the input receiving unit 23 (for example, a voltage signal corresponding to on / off) is taken up by the control unit 21 (microcontroller).

[0048] The display unit 24 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 control unit 21 (microcontroller).

[0049] The control unit 21 sets the dimming level and performs other operations according to the operation input received from the input receiving unit 23. The control unit 21 also displays the dimming level currently being received by the input receiving unit 23 on the display unit 24. In other words, the user can perform the setting work while confirming the dimming level by the numbers and letters displayed on the display unit 24.

[0050] (2-3) Operation of the lighting control device The lighting console C1 transmits control commands via DMX signals to the communication unit 22 of the lighting control device A1 to instruct the flashing (switching between on and off), dimming (adjusting the light intensity), and color adjustment (adjusting the color of the light) of the light emitted from the light source unit 4 of the lighting device B1. The control commands transmitted from the lighting console C1 to the lighting device B1 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.

[0051] These control commands are given for each of the six types of LED40. For example, the color temperature control command specifies the ratio of the dimming levels of the six types of LED40, from the first LED40R to the sixth LED40EG.

[0052] For example, let's consider a case where the dimming levels of the six types of LED40 are adjusted to a ratio of 1:1:1:2:1:1 for the light color. In this case, if the dimming level of the fourth LED40A, which has the highest ratio, is set to 100%, then the dimming levels of the other five types of LED40 will be 50%. Then, if the light intensity is halved without changing the light color, if the dimming level of the fourth LED40A, which has the highest ratio, is set to 50%, then the dimming levels of the other five types of LED40 will be 25%.

[0053] Here, the data indicating the dimming level in the DMX signal and the data indicating the dimming level in the control unit 21 of the lighting control device A1 do not match. For example, let's call the data indicating the dimming level in the DMX signal the dimming signal value L, and the data indicating the dimming level in the control unit 21 the total dimming value La. In this case, the coefficient for converting the dimming signal value L to the total dimming value La is given by Dset as the correction value corresponding to an arbitrary dimming signal value L, and Dmax as the correction value corresponding to the maximum value of the dimming signal value L (the dimming signal value when the dimming level is 100%), then the total dimming value La can be expressed as La = (Dset / Dmax) × L. Note that the maximum value Lmax of the total dimming value La corresponds to a dimming level of 100%. Therefore, the following relationship holds between the target value It of the output current corresponding to the total dimming value La and the maximum value of the target value (the target value corresponding to a dimming level of 100%). Since L / Lmax is known as the dimming level of the DMX signal, Dset / Dmax corresponds to the correction data for the current (target value of the output current).

[0054] It=(La / Lmax)×Imax=(Dset / Dmax)×(L / Lmax)×Imax Furthermore, if we consider α (<1) as the correction factor used to bring the current-luminous flux characteristics of LED40, shown by the solid line X2 in Figure 2, closer to a direct proportional relationship, then the target value of the output current It can be expressed by the following equation 1 using the correction factor α.

[0055]

number

[0056] Here, the first term on the right-hand side of equation 1 can be expressed as 1 - (1 - La / Lmax) × α, which is 1 when the total dimming value La is equal to the maximum value Lmax, and 1 - α when the total dimming value La is equal to the minimum value (zero). In other words, the correction coefficient α that brings the solid line X2 closer to the dashed line X1 in Figure 2 corresponds to the slope of the straight line X3 (see Figure 6). However, the value of the correction coefficient α will be different for each of the six types of LEDs 40.

[0057] Next, we expand equation 1 by considering it as a quadratic equation for the correction value Dset when the dimming level is 100%. If we set L = Lmax, equation 1 can be transformed into equation 2.

[0058]

number

[0059] By moving the right-hand side of equation 2 to the left-hand side and expanding it, it can be transformed into a quadratic equation with a correction value Dset, as in equation 3.

[0060]

number

[0061] Here, using the quadratic formula, the correction value Dset can be expressed by equations 4 and 5.

[0062]

number

[0063]

number

[0064] In equation 5, It / Imax corresponds to the dimming level. Therefore, using equations 4 and 5, the correction value Dset can be calculated for any dimming level (0% to 100%).

[0065] The memory unit 20 stores characteristic data (correction coefficient α) for each of the six types of LEDs 40, and current correction data (correction value Dset) for each of the six types of LEDs 40. When the control unit 21 receives the dimming level of each of the six types of LEDs 40 (dimming level based on the control command of the dimming console C1) from the communication unit 22, it uses the characteristic data (correction coefficient α) and current correction data (correction value Dset) stored in the memory unit 20 to calculate the target value It for each of the six types of LEDs 40 from equation 2. The control unit 21 then controls the six current output units 10 to match the calculated target value It for each of the six types of LEDs 40. Alternatively, the control unit 21 may pre-calculate the target value It for each of the six types of LEDs 40 corresponding to the dimming level, and store the calculated target value It for each of the six types of LEDs 40 in the memory unit 20 in correspondence with the dimming level.

[0066] However, since the lighting control device A1 includes a control unit 21 that corrects the target value for the control command by referring to characteristic data and correction data as described above, it is possible to bring the change in current (output current of the current output unit 10) to the control command closer to a direct proportion. As a result, the lighting control device A1 can suppress changes in light output (luminous flux) caused by variations in the output characteristics of the LED 40.

[0067] Furthermore, in the lighting control device A1, the control unit 21 sets target values ​​for each of the multiple types (six types in the embodiment) of LEDs 40 based on the control command, and corrects the target values ​​for the control command by referring to the characteristic data and correction data for each of the multiple types of LEDs 40. Therefore, the lighting control device A1 can perform color tuning and brightness tuning of the light obtained by mixing multiple types of LEDs 40, while suppressing changes in light output (luminous flux) (color shift) caused by variations in the output characteristics of the multiple types of LEDs 40.

[0068] Furthermore, in the lighting control device A1, the control unit 21 may correct the target value within at least a portion of the adjustment range of the entire range from the minimum to the maximum value of the output current of the current output unit 10. For example, the human eye has the characteristic that it is more difficult to perceive changes in light intensity when the light intensity is high (when the dimming level is high) compared to when the light intensity is low (when the dimming level is low). Therefore, the control unit 21 in the lighting control device A1 may correct the target value It within a range where the dimming level is relatively low (for example, a range where the dimming level is less than 50%). However, the range in which the control unit 21 corrects the target value It is not limited to a range where the dimming level is less than 50%.

[0069] However, the lighting control device A1 can reduce the processing load on the control unit 21 by having the control unit 21 correct the target value within at least a portion of the adjustment range of the entire range from the minimum value to the maximum value of the output current of the current output unit 10.

[0070] (3) Variant Next, several modifications of the lighting control device A1 according to the embodiment will be described. However, the basic configuration of each modification described below is common to the basic configuration of the embodiment. Therefore, components that are common to or substantially common to the basic configuration of the embodiment will be denoted by the same reference numerals, and their illustration and description will be omitted as appropriate. In the following description, "substantially common configuration" means a configuration that differs slightly in shape, size, etc., but has the same function.

[0071] (3-1) Variation 1 The lighting control device A1 of the modified example 1 is characterized by storing the corrected target value It in a table format in the storage unit 20, and by referring to the storage unit 20 to set the target value based on the control command in the control unit 21.

[0072] In other words, the lighting control device A1 of the modified example 1 pre-calculates a target value It corresponding to the dimming signal value L included in the control command, and stores the calculated target value It (corrected target value It) in a data table corresponding to the dimming signal value L in the storage unit 20.

[0073] Then, in the modified example 1, when the control unit 21 receives a dimming signal value L from the communication unit 22, it refers to the data table of the storage unit 20 and sets the corrected target value It.

[0074] However, the lighting control device A1 of the modified example 1 has the advantage of reducing the processing load on the control unit 21 compared to the case where the corrected target value It is calculated each time a control command is received.

[0075] (3-2) Modification 2 The lighting control device A1 of the modified example 2 is characterized in that the control unit 21 corrects the target value It by taking into account the temperature characteristics of the LED 40.

[0076] LED40s typically tend to experience a decrease in luminous efficiency as their temperature rises due to self-heating. In other words, as the temperature of the LED40 increases, the amount of light it emits decreases, so the current needs to be increased to maintain a constant light output.

[0077] Therefore, in the modified example 2, the lighting control device A1 measures the temperature of the light source unit 4 and includes a temperature coefficient corresponding to the measured temperature in the characteristic data. For example, the control unit 21 in the modified example 2 can calculate the target value It using the value obtained by multiplying the correction coefficient α by the temperature coefficient.

[0078] However, in the modified example 2, the lighting control device A1 has a control unit 21 that corrects the target value It considering the temperature characteristics of the LED 40, so changes in light output (luminous flux) caused by variations in the output characteristics of the LED 40 can be further suppressed.

[0079] (4) Summary A lighting control device (A1) according to a first aspect of the present disclosure comprises a current output unit (10) that outputs current to one or more LEDs (40), a storage unit (20), and a control unit (21). The storage unit (20) stores characteristic data (correction coefficient α) and current correction data (Dset) relating to the output characteristics of the LEDs (40). The control unit (21) sets a target value (It) of the current based on a control command input from an external source and controls the current output unit (10) to make the current match the target value (It). The control unit (21) refers to the characteristic data and the correction data and corrects the target value (It) for the control command.

[0080] The lighting control device (A1) according to the first embodiment includes a control unit (21) that corrects the target value (It) for a control command by referring to characteristic data and correction data, so that the change in current for the control command can be brought closer to a direct proportionality. As a result, the lighting control device (A1) according to the first embodiment can suppress changes in light output (luminous flux) caused by variations in the output characteristics of the LED (40).

[0081] A lighting control device (A1) according to a second aspect of this disclosure can be realized in combination with the first aspect. In the lighting control device (A1) according to the second aspect, it is preferable that the control unit (21) corrects the target value (It) within an adjustment range that is at least a portion of the entire range from the minimum to the maximum value of the current.

[0082] The lighting control device (A1) according to the second embodiment can reduce the processing load on the control unit (21).

[0083] A lighting control device (A1) according to a third aspect of this disclosure can be realized in combination with the first or second aspect. In the lighting control device (A1) according to the third aspect, the correction data preferably includes a correction coefficient (α) that is multiplied by the target value (It).

[0084] The lighting control device (A1) according to the third embodiment can reduce the processing load on the control unit (21).

[0085] A lighting control device (A1) according to a fourth aspect of this disclosure can be realized by combination with any of the first to third aspects. In the lighting control device (A1) according to the fourth aspect, the characteristic data preferably represents the relationship between the current flowing through the LED (40) and the light output radiated from the LED (40).

[0086] The lighting control device (A1) according to the fourth embodiment corrects the light output (luminous flux) due to variations in the output characteristics of the LED (40) by characteristic data (correction coefficient α) that represents the relationship between the current flowing through the LED (40) and the light output radiated from the LED (40).

[0087] A lighting control device (A1) according to a fifth aspect of this disclosure can be realized in combination with any of the first to fourth aspects. In the lighting control device (A1) according to the fifth aspect, the storage unit (20) preferably stores the corrected target value (It) in a table format. The control unit (21) preferably sets the target value based on the control command by referring to the storage unit (20).

[0088] The lighting control device (A1) according to the fifth embodiment can reduce the processing burden on the control unit (21) compared to the case where the corrected target value (It) is calculated each time a control command is received.

[0089] A lighting control device (A1) according to a sixth aspect of this disclosure can be realized by combination with any of the first to fifth aspects. The lighting control device (A1) according to the sixth aspect preferably includes a plurality of current output units (first current output unit 11, second current output unit 12, third current output unit 13, fourth current output unit 14, fifth current output unit 15, sixth current output unit 16) that correspond one-to-one with a plurality of types of LEDs (40R, 40G, 40B, 40A, 40SB, 40EG) with different light colors and output current to the corresponding LEDs (40R, 40G, 40B, 40A, 40SB, 40EG). The storage unit (20) preferably stores characteristic data and correction data for each of the plurality of types of LEDs (40; first LED 40R, second LED 40G, third LED 40B, fourth LED 40A, fifth LED 40SB, sixth LED 40EG). The control unit (21) preferably sets a target value (It) for each of the multiple types of LEDs (40) based on the control command, and corrects the target value (It) for the control command by referring to characteristic data and correction data for each of the multiple types of LEDs (40).

[0090] The lighting control device (A1) according to the sixth embodiment can adjust the color and brightness of the light obtained by mixing multiple types of LEDs (40) while suppressing changes in light output (luminous flux) (color shift) caused by variations in the output characteristics of multiple types of LEDs (40).

[0091] A lighting device (B1) according to the seventh aspect of this disclosure comprises a light source (light source unit 4) including one or more LEDs (40), and a lighting control device (A1) according to any of the first to fifth aspects.

[0092] The lighting device (B1) according to the seventh embodiment can suppress changes in light output (luminous flux) caused by variations in the output characteristics of the LED (40).

[0093] The lighting device (B1) according to the eighth aspect of this disclosure comprises a light source (light source unit 4) including multiple types of LEDs (40R, 40G, 40B, 40A, 40SB, 40EG) with different light colors, and a lighting control device (A1) according to the sixth aspect.

[0094] The lighting device (B1) according to the eighth embodiment can adjust the color and brightness of the light obtained by mixing multiple types of LEDs (40) while suppressing changes in light output (luminous flux) (color shift) caused by variations in the output characteristics of multiple types of LEDs (40). [Explanation of Symbols]

[0095] A1 Lighting control device B1 lighting equipment 4. Light source unit (light source) 10 Current output section 11. Output section of the first current 12. Second current output section 13. Third current output section 14. Output section of the fourth current 15. Fifth Current Output Section 16. Output section of the sixth current 20 Memory section 21 Control Unit 40 LED 40R 1st LED 40G 2nd LED 40B 3rd LED 40A 4th LED 40SB 5th LED 40EG 6th LED It output current target value α Complementary coefficient (characteristic data) Dset Correction Value (Correction Data)

Claims

1. A current output unit that outputs current to one or more LEDs, A storage unit that stores characteristic data relating to the output characteristics of the LED and correction data for the current, A control unit sets a target value for the current based on a control command input from an external source and controls the current output unit to make the current match the target value, Equipped with, The control unit refers to the characteristic data and the correction data and corrects the target value for the control command. Lighting control device.

2. The control unit corrects the target value within an adjustment range that is at least a portion of the entire range from the minimum value to the maximum value of the current. The lighting control device according to claim 1.

3. The correction data includes a correction coefficient that is multiplied by the target value. The lighting control device according to claim 1 or 2.

4. The aforementioned characteristic data represents the relationship between the current flowing through the LED and the light output emitted from the LED. The lighting control device according to claim 1 or 2.

5. The storage unit stores the corrected target value in a table format. The control unit sets the target value based on the control command by referring to the storage unit. The lighting control device according to claim 1 or 2.

6. The system comprises multiple current output units that correspond one-to-one with multiple types of LEDs that have different light colors and output the current to the corresponding LEDs. The storage unit stores the characteristic data and the correction data for each of the multiple types of LEDs. The control unit sets the target value for each of the multiple types of LEDs based on the control command, refers to the characteristic data and correction data for each of the multiple types of LEDs, and corrects the target value for the control command. The lighting control device according to claim 1 or 2.

7. A light source including one or more LEDs, A lighting control device according to claim 1 or 2, Equipped with, Lighting device.

8. A light source containing multiple types of LEDs with different light colors, The lighting control device according to claim 6, Equipped with, Lighting device.

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