Lighting control device and lighting fixture

Abstract

To provide a lighting control device and a lighting fixture which can change a light emission quantity and a color temperature of a light source part while suppressing discomfort of a user.SOLUTION: A lighting control device includes a lighting circuit for lighting a light source including a first light source, a second light source having a different color temperature from that of the first light source, and a control circuit for controlling the lighting circuit, and controlling a first light emission quantity of the first light source and a second light emission quantity of the second light source, wherein the control circuit changes the light emission quantity and the color temperature of the light source part during a fading time while changing a first change rate of the first light emission quantity and a second change rate of the second light emission quantity, the first change rate of a second unit time immediately after a first unit time during the fading time is obtained by adding a prescribed first fixed value to the first change rate of the first unit time, and the second change rate of the second unit time is obtained by subtracting a prescribed second fixed value from the second change rate of the first unit time.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present disclosure relates to a lighting control device and a lighting fixture. [Background technology]

[0002] Patent Document 1 discloses a lighting control device including multiple lighting circuits and a control unit. The multiple lighting circuits are electrically connected to multiple light sources, respectively, and are configured to adjust the output power supplied to each of the light sources. The control unit is configured to control the multiple lighting circuits to adjust the output power. The control unit is further configured to gradually change the light color of the illumination light between a first light color having a relatively high color temperature and a second light color having a relatively low color temperature, changing the light color at a first time rate in a range close to the first light color. The control unit is further configured to change the light color at a second time rate smaller than the first time rate in a range close to the second light color. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2017-21952 Summary of the Invention [Problem to be solved by the invention]

[0004] Patent Document 1 does not describe performing color adjustment control and dimming control simultaneously. If the light emission amount and color temperature of the light source unit are changed simultaneously, the user may feel uncomfortable.

[0005] The present disclosure has been made to solve the above-mentioned problems, and aims to provide a lighting control device and lighting fixture that can change the light emission amount and color temperature of the light source unit while suppressing discomfort to the user. [Means for solving the problem]

[0006] A lighting control device according to the present disclosure includes: a lighting circuit that turns on a light source unit including a first light source and a second light source having a color temperature different from that of the first light source; and a control circuit that controls the lighting circuit to control a first light emission amount of the first light source and a second light emission amount of the second light source, wherein the control circuit changes the light emission amount and color temperature of the light source unit during a fade time while changing a first rate of change of the first light emission amount and a second rate of change of the second light emission amount, and the first rate of change for a second unit time immediately after a first unit time of the fade time is obtained by adding a predetermined first fixed value to the first rate of change for the first unit time, and the second rate of change for the second unit time is obtained by subtracting a predetermined second fixed value from the second rate of change for the first unit time. The first fixed value and the second fixed value are different. do. [Effects of the Invention]

[0007] In the lighting control device according to the present disclosure, the control circuit changes the light emission intensity and color temperature of the light source unit during the fade time while changing the rate of change of the light emission intensity of the first light source and the rate of change of the light emission intensity of the second light source, thereby making it possible to change the light emission intensity and color temperature of the light source unit while minimizing discomfort felt by the user. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a block diagram showing a lighting fixture according to a first embodiment. [Figure 2] FIG. 10 is a block diagram showing a lighting fixture according to a modified example of the first embodiment. [Figure 3] FIG. 4 is a diagram illustrating fade control according to a first comparative example of the first embodiment. [Figure 4] FIG. 10 is a diagram illustrating fade control according to a second comparative example of the first embodiment. [Figure 5] FIG. 10 is a diagram illustrating fade control according to a third comparative example of the first embodiment. [Figure 6] FIG. 2 is a diagram illustrating fade control according to the first embodiment. [Figure 7]5 is a diagram illustrating the rate of change in the amount of light emitted by a first light source and the rate of change in the amount of light emitted by a second light source according to the first embodiment. FIG. [Figure 8] FIG. 10 is a diagram illustrating fade control according to the second embodiment. [Figure 9] 10 is a diagram illustrating the rate of change in the amount of light emitted by a first light source and the rate of change in the amount of light emitted by a second light source according to the second embodiment. FIG. [Figure 10] FIG. 10 is a diagram illustrating fade control according to the third embodiment. [Figure 11] 10 is a diagram illustrating the rate of change in the amount of light emitted by a first light source and the rate of change in the amount of light emitted by a second light source according to the third embodiment. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0009] A lighting control device and a lighting fixture according to each embodiment will be described with reference to the drawings. The same or corresponding components are designated by the same reference numerals, and repeated description may be omitted.

[0010] Embodiment 1 FIG. 1 is a block diagram showing a lighting fixture 1 according to a first embodiment. The lighting fixture 1 includes a lighting control device 10 and a light source unit. The light source unit includes a first light source 100 and a second light source 200 that has a different color temperature from the first light source 100. The lighting control device 10 includes a first lighting circuit 21 and a second lighting circuit 22 as lighting circuits that light the light source unit. A control circuit 31 controls the lighting circuits to control the light emission intensity of the first light source 100 and the light emission intensity of the second light source 200.

[0011] The input side of the lighting control device 10 is connected to a commercial AC power source. The lighting control device 10 may also be connected to a DC power source. When a DC power source is connected to the lighting control device 10, the rectifier circuit 11 and PFC (Power Factor Correction) circuit 12, which will be described later, are not required. The output side of the lighting control device 10 is connected to the first light source 100 and the second light source 200.

[0012] The lighting control device 10 includes an input filter, a rectifier circuit 11, a PFC circuit 12, a first lighting circuit 21, a second lighting circuit 22, and a control circuit 31. The rectifier circuit 11 rectifies AC power supplied from a commercial AC power source and converts it into a pulsating current. The rectifier circuit 11 is, for example, a full-wave rectifier circuit. The rectifier circuit 11 is configured, for example, by a diode bridge. The PFC circuit 12 is connected to the output of the rectifier circuit 11. The PFC circuit 12 converts the pulsating current output from the rectifier circuit 11 into DC power and outputs it. The PFC circuit 12 is, for example, a boost chopper. The PFC circuit 12 is configured, for example, by a coil, a switching element, and a diode, all of which are not shown.

[0013] The input of the first lighting circuit 21 and the input of the second lighting circuit 22 are connected in parallel to the output of the PFC circuit 12. The first lighting circuit 21 is, for example, a switching circuit such as a so-called buck converter circuit that supplies power to the first light source 100. The first lighting circuit 21 includes, for example, a switching element, a diode, a coil, a capacitor, and a resistor. The second lighting circuit 22 is configured similarly to the first lighting circuit 21 and supplies power to the second light source 200.

[0014] The control circuit 31 is, for example, a microcomputer. The number of microcomputers constituting the control circuit 31 may be one or more. The control circuit 31 outputs a PFC control signal to the switching elements so that the output voltage of the PFC circuit 12 becomes a predetermined value. The control circuit 31 also outputs a first lighting control signal and a second lighting control signal to the switching elements of the first lighting circuit 21 and the second lighting circuit 22, respectively, so that the currents flowing through the first light source 100 and the second light source 200 become predetermined values. The control circuit 31 can individually adjust the output amounts of the first lighting circuit 21 and the second lighting circuit 22.

[0015] The control circuit 31 can gradually change, over a predetermined fade time, each of the outputs of the PFC circuit 12, the first lighting circuit 21, and the second lighting circuit 22. The control circuit 31 may also change the outputs of the PFC circuit 12, the first lighting circuit 21, and the second lighting circuit 22 continuously or stepwise over the fade time.

[0016] The first light source 100 and the second light source 200 emit light brighter as the current flowing therethrough increases, and the light emits light dimmer as the current flowing therethrough decreases. The lighting device 1 emits illumination light obtained by mixing the colors of the light emitted by the first light source 100 and the second light source 200. The color temperature of the illumination light varies depending on the ratio of the light emission intensity of the first light source 100 and the second light source 200. Therefore, the color temperature of the illumination light varies with changes in the output of the first lighting control signal and the second lighting control signal. Furthermore, the light emission intensity, which is the overall brightness of the lighting device 1, also varies with changes in the output of the first lighting control signal and the second lighting control signal.

[0017] For example, the color temperature of the first light source 100 is 5000 K, and the color temperature of the second light source 200 is 3000 K. Table 1 shows an example of the output ratio of the first light source 100 and the second light source 200 to the rated value of the light emission amount in this case.

[0018] [Table 1]

[0019] In Table 1, for Nos. 1-1 to 1-5, the light output of the entire fixture is 100%. The color temperature of the entire fixture varies within a range of 5000 to 3000 K depending on the ratio of the light output of the first light source 100 and the second light source 200. Similarly, for Nos. 2-1 to 2-5, the light output of the entire fixture is 30%. The color temperature of the entire fixture also varies within a range of 5000 to 3000 K. In this way, the light output and color temperature of the entire fixture are determined by the ratio and total of the light output of the first light source 100 and the second light source 200.

[0020] 2 is a block diagram showing a lighting fixture 1 according to a variation of the first embodiment. Control circuit 31 may receive control information transmitted from an external control device 2 and perform lighting control based on the control information. The control information may include, for example, information regarding the light emission level of each of first lighting circuit 21 and second lighting circuit 22, the light emission level or color temperature of lighting fixture 1 as a whole, or fade time.

[0021] Next, fade control will be described. First, first to third comparative examples of this embodiment will be described. In the first comparative example, the light emission amount of the entire fixture is changed over time at a constant rate during the fade time. Table 2 shows the changes in light emission amount and color temperature in the first comparative example. FIG. 3 is a diagram illustrating fade control according to the first comparative example of embodiment 1.

[0022] [Table 2]

[0023] In the first comparative example, the fade time is 1 second. The light intensity of both the first light source 100 and the second light source 200 before the fade begins is 0%. In other words, at time T=0 ms, the lighting fixture 1 is off. After the fade is complete at time T=1000 ms, the light intensity of the first light source 100 is 75% and the light intensity of the second light source 200 is 25%. In other words, the light intensity of the entire fixture is 100%, and the color temperature of the entire fixture is 4500K. During the fade time, the light intensity of the first light source 100 and the second light source 200 each changes at a constant rate every 1 ms. The rate of change of the light intensity of the entire fixture is 0.1% / 1 ms.

[0024] When the light output of each light source is changed by a constant percentage, the light output of the entire fixture also changes by a constant percentage, while the color temperature of the entire fixture remains constant regardless of the time elapsed since the fade started.

[0025] Next, in a second comparative example, the color temperature of the entire fixture is changed over time at a constant rate during the fade time. Table 3 shows the changes in light emission amount and color temperature in the second comparative example. Figure 4 is a diagram illustrating fade control according to the second comparative example of embodiment 1.

[0026] [Table 3]

[0027] In the second comparative example, the fade time is 1 second. At time T=0 ms before the fade begins, the color temperature is 4500K. At this time, the light emission level of the first light source 100 is 75%, the light emission level of the second light source 200 is 25%, and the light emission level of the entire fixture is 100%. After the fade is complete at time T=1000 ms, the color temperature of the entire fixture is 3500K. At this time, the light emission level of the first light source 100 is 25%, the light emission level of the second light source 200 is 75%, and the light emission level of the entire fixture is 100%. During the fade time, the light emission levels of the first light source 100 and the second light source 200 change so that the color temperature of the entire fixture changes at a constant rate every 1 ms. The rate of change of the color temperature of the entire fixture is 1K / 1 ms.

[0028] During the fade time, the light output of the entire fixture remains constant, while the color temperature of the entire fixture changes at a constant rate.

[0029] In this way, by changing the light emission amount of the first light source 100 and the second light source 200 at a constant rate, it is possible to change either the light emission amount or the color temperature at a constant rate.

[0030] Next, as a third comparative example, consider a case where the light emission amount of each light source is changed at a constant rate to simultaneously change the light emission amount and color temperature. Table 4 shows the changes in light emission amount and color temperature in the third comparative example. Figure 5 is a diagram illustrating fade control according to the third comparative example of embodiment 1.

[0031] [Table 4]

[0032] In the third comparative example, the fade time is 1 second. At time T=0 ms before the fade starts, the light emission intensity of the first light source 100 is 100% and the light emission intensity of the second light source 200 is 0%. In other words, the light emission intensity of the entire fixture is 100% and the color temperature of the entire fixture is 5000K. After the fade is completed at time T=1000 ms, the light emission intensity of the entire fixture is 0% for the first light source 100 and 30% for the second light source 200. In other words, the light emission intensity of the entire fixture is 30% and the color temperature of the entire fixture is 3000K. During the fade time, the light emission intensity of the first light source 100 and the second light source 200 each change at a fixed rate every 1 ms.

[0033] As shown in Figure 5, the light output of the entire fixture changes at a constant rate during the fade time. However, the color temperature changes nonlinearly. This may cause discomfort to the user. Furthermore, if the color temperature of each light source is changed at a constant rate, changing the light output and color temperature simultaneously, the light output of the entire fixture will change nonlinearly. This may also cause discomfort to the user.

[0034] Next, the fade control of this embodiment will be described. The control circuit 31 of this embodiment changes the light emission intensity and color temperature of the light source units during the fade time while changing the rate of change of the light emission intensity of the first light source 100 and the rate of change of the light emission intensity of the second light source 200. In the following, the color temperature of the entire fixture is referred to as Csum, and the light emission intensity of the entire fixture is referred to as Lsum. The control circuit 31 can preset the fade time Fade, the color temperature Csum_0 and light emission intensity Lsum_0 of the entire fixture at the start of the fade, and the color temperature Csum_T and light emission intensity Lsum_T of the entire fixture after the fade has ended to any value.

[0035] The control circuit 31 controls the light emission amount L1 of the first light source 100 and the light emission amount L2 of the second light source 200, respectively, to maintain constant the rate of change ΔLsum of the light emission amount Lsum of the light source unit over fade time and the rate of change ΔCsum of the color temperature Csum of the light source unit over fade time. Here, the rate of change corresponds to the amount of change per unit time. In this embodiment, L1 and L2 change, for example, like a quadratic function. Below is an example showing the changes in L1 and L2 using a recurrence formula.

[0036] Lsum, Csum, L1, and L2 at T=n+1 and T=n during the fade time are expressed by the following equations 1 to 4, respectively. Lsum_(n+1)=Lsum_n + ΔLsum (Equation 1) Csum_(n+1)=Csum_n + ΔCsum (Equation 2) L1_(n+1)=L1_n + ΔL1_n (Equation 3) L2_(n+1)=L2_n + ΔL2_n (Equation 4)

[0037] Lsum and Csum change by fixed change rates ΔLsum and ΔCsum, respectively. On the other hand, for L1 and L2, change rates ΔL1_n and ΔL2_n change by fixed values ​​α and β to satisfy Equations 1 and 2. The change rates ΔL1_n and ΔL2_n are expressed by the following Equations 5 and 6.

[0038] ΔL1_(n+1)=ΔL1_n + α (Equation 5) ΔL2_(n+1)=ΔL2_n + β (Equation 6)

[0039] Table 5 shows the changes in the amount of light emitted and the color temperature according to embodiment 1. Fig. 6 is a diagram illustrating fade control according to embodiment 1. Fig. 7 is a diagram illustrating the rate of change in the amount of light emitted by the first light source 100 and the rate of change in the amount of light emitted by the second light source 200 according to embodiment 1.

[0040] [Table 5]

[0041] As an example, in Table 5, Figures 6 and 7, Fade = 1000 ms, Csum_0 = 4000 K, Lsum_0 = 10%, Csum_T = 3500 K, and Lsum_T = 100%. In this case, ΔL1 and ΔL2 change per unit time by α = -0.000045% and β = -α = 0.000045% so that ΔLsum = 0.09% and ΔCsum = -0.5 K.

[0042] In this manner, in this embodiment, control circuit 31 changes the light emission amount Lsum and color temperature Csum of the entire device while changing ΔL1 and ΔL2 during the fade time. This makes it possible to change the light emission amount Lsum and color temperature Csum of the entire device while minimizing any discomfort felt by the user.

[0043] In this embodiment, β = -α. That is, the rate of change ΔL1_(n+1) of the second unit time n+1 immediately following the first unit time n in the fade time Fade is obtained by adding a predetermined fixed value α to the rate of change ΔL1_n of the first unit time n. Also, the rate of change ΔL2_(n+1) of the second unit time n+1 is obtained by subtracting the fixed value α from the rate of change ΔL2_n of the first unit time n. This makes it easy to keep ΔLsum and ΔCsum constant during the fade time, reducing any discomfort felt by the user.

[0044] Note that ΔLsum and ΔCsum do not have to be constant during the fade time as long as the discomfort felt by the user can be reduced. In other words, β≠-α is acceptable. This allows for a more flexible dimming curve.

[0045] ΔL1_0, ΔL2_0, α, and β can be uniquely determined based on Fade, Csum_0, Lsum_0, Csum_T, Lsum_T, the color temperature C1 of the first light source 100, and the color temperature C2 of the second light source 200. That is, by presetting the values ​​of at least Fade, L1_0, L2_0, ΔL1_0, ΔL2_0, and α, it is possible to arbitrarily set the fade control of the color temperature and light emission intensity of the entire fixture. In this way, the control circuit 31 changes the light emission intensity Lsum and the color temperature Csum based on the fade time Fade, the fixed value α, the change rates ΔL1_0 and ΔL2_0 in the first unit time of the fade time, and the initial light emission intensity values ​​L1_0 and L2_0.

[0046] Here, the values ​​of ΔL1_0, ΔL2_0, and α can be calculated from Fade, L1_0, L1_T, L2_0, and L2_T. Therefore, the values ​​that are preset in the control circuit 31 described above are not limited to the direct values ​​of ΔL1_0, ΔL2_0, and α, but may be values ​​from which these values ​​can be calculated. For example, Fade, L1_0, L1_T, L2_0, and L2_T may be preset in the control circuit 31. Furthermore, when β≠-α, the value of β or a value from which β can be calculated may be preset in the control circuit 31.

[0047] In this embodiment, the light emission amount is changed every 1 ms. However, this is not limiting and the light emission amount may be changed every arbitrary unit time. For example, if the unit time is 10 ms, ΔLsum = 0.9% and ΔCsum = -5K.

[0048] 6 and 7, L1 and L2 change in the form of a quadratic function. However, this is not limiting, and L1 and L2 may change in the form of any function that suppresses the user's discomfort caused by changes in color temperature and light emission amount.

[0049] In this embodiment, the control circuit 31 calculates L1 and L2 by a calculation using a recurrence formula. However, the present invention is not limited to this. The control circuit 31 may store a table showing the time changes of L1 and L2 in the internal memory 32. The control circuit 31 may also store the rate of change ΔL1 per unit time and the rate of change ΔL2 per unit time in the internal memory 32.

[0050] In this embodiment, the light source section has a first light source 100 and a second light source 200. However, the light source section is not limited to this and may have three or more types of light sources with different color temperatures.

[0051] These modifications can be applied as appropriate to the lighting control devices and lighting fixtures according to the following embodiments. Note that the lighting control devices and lighting fixtures according to the following embodiments have many things in common with embodiment 1, so the following description will focus on the differences from embodiment 1.

[0052] Embodiment 2 In this embodiment, the control circuit 31 receives an arbitrary fade time Fade, a fixed value α, and change rates ΔL1_0 and ΔL2_0 from an external control device 2, etc. In response to this, the control circuit 31 updates each value to achieve fade control.

[0053] Also, similar to the first embodiment, the values ​​that the control circuit 31 receives from the outside are not limited to the direct values ​​of ΔL1_0, ΔL2_0, and α, but may be values ​​from which these values ​​can be calculated. That is, the control circuit 31 may receive from the outside the fixed value α, values ​​from which the change rates ΔL1_0 and ΔL2_0 can be calculated, and the fade time Fade. Furthermore, when β≠-α, the control circuit 31 may receive from the outside the value of β or a value from which β can be calculated. Note that some of the above values ​​may be transmitted from the outside to the control circuit 31 and updated.

[0054] In this embodiment, by transmitting setting values ​​to the control circuit 31 from the outside, it is possible to adjust the light and color with any fade time, any light emission amount, and any color temperature.

[0055] Table 6 shows changes in the amount of light emitted and color temperature according to embodiment 2. Fig. 8 is a diagram illustrating fade control according to embodiment 2. Fig. 9 is a diagram illustrating the rate of change in the amount of light emitted by the first light source 100 and the second light source 200 according to embodiment 2.

[0056] [Table 6]

[0057] Before fade control begins at time T<0, the lighting fixture 1 is lit with Csum=3500K, Lsum=100%, L1=25%, and L2=75%. At time T=0, the lighting fixture 1 receives Fade=500ms, ΔL1_0=0.05984%, ΔL2_0=-0.21984%, and α=-0.00032% transmitted from an external device, and begins fade control. When time T=500=Fade is reached, the control circuit 31 ends fade control. After this, the lighting fixture 1 continues to be lit with Csum=4500K, Lsum=20%, L1=15%, and L2=5%.

[0058] Embodiment 3 In the first or second embodiment, dimming and color adjustment were performed by changing the light output and color temperature of the entire fixture at a constant rate throughout the entire fade time. In this embodiment, the fade time is divided into multiple parts. Control similar to that in the first or second embodiment is performed for each of the multiple divided fade times. In the first or second embodiment, lighting fixture 1 is controlled using a linear dimming and color adjustment curve. In this embodiment, control using a dimming and color adjustment curve with a greater degree of freedom can be achieved.

[0059] Table 7 shows the changes in the amount of light emitted and the color temperature according to embodiment 3. Fig. 10 is a diagram illustrating fade control according to embodiment 3. Fig. 11 is a diagram illustrating the rate of change in the amount of light emitted by the first light source 100 and the rate of change in the amount of light emitted by the second light source 200 according to embodiment 3. In Table 7, Figs. 10 and 11, the fade time is divided into three periods F1, F2, and F3.

[0060] [Table 7]

[0061] Of the total fade time T=1000ms, T=0 to 200ms is the first fade time F1, T=201 to 400ms is the second fade time F2, and T=401 to 1000ms is the third fade time F3. The operation during each period is described below.

[0062] (First fade time F1) The light output is changed over 200 ms from a lighting state of Csum=3500K, Lsum=100%, L1=25%, and L2=75% to Csum=4000K, Lsum=50%, L1=25%, and L2=25%. Focusing on L1, the light output before and after the fade is the same at 25%. Meanwhile, the light output during the fade period is a value other than 25%. Even if the light output before and after the fade is the same, the light output during the fade period may change depending on the relationship between Csum, Lsum, and L2. This type of control allows for the dimming and color adjustment curve of the entire fixture to be achieved while minimizing discomfort to the user.

[0063] (Second fade time F2) The lighting state at T=200, the end of the first fade time F1, is the initial state, and the light output is changed over 200 ms so that Csum=4200K, Lsum=25%, L1=15%, and L2=10%. Because ΔCsum and ΔLsum are smaller than those in the first fade time F1, the light output and color temperature change gradually.

[0064] (Third fade time F3) The lighting state at T=400, the end of the second fade time F2, is the initial state, and the light output is changed over 400 ms so that Csum=4500K, Lsum=20%, L1=15%, and L2=5%. The fade time F3 is longer than the first fade time F1 and the second fade time F2. However, because ΔCsum and ΔLsum are small, the light output and color temperature change even more gradually.

[0065] As described above, in this embodiment, the entire fade time is divided into multiple parts, and an example has been shown in which Csum and Lsum change more gradually as the fade time becomes later. However, this is not limiting, and Csum and Lsum may change more rapidly as the fade time becomes later. Alternatively, one of Csum and Lsum may change more slowly and the other may change more rapidly as the fade time becomes later. Furthermore, one of the rates of change of Csum and Lsum may be constant throughout the entire fade time, while the other may vary for each fade time.

[0066] The technical features described in each embodiment may be used in appropriate combination. [Explanation of symbols]

[0067] 1 lighting fixture, 2 control device, 10 lighting control device, 11 rectifier circuit, 12 PFC circuit, 21 first lighting circuit, 22 second lighting circuit, 31 control circuit, 32 memory, 100 first light source, 200 second light source, AC commercial power supply

Claims

1. a lighting circuit that lights up a light source unit including a first light source and a second light source having a color temperature different from that of the first light source; a control circuit that controls the lighting circuit to control a first light emission amount of the first light source and a second light emission amount of the second light source; Equipped with the control circuit changes the light emission amount and the color temperature of the light source unit during a fade time while changing a first rate of change of the first light emission amount and a second rate of change of the second light emission amount; the first rate of change of a second unit time immediately following a first unit time during the fade time is obtained by adding a predetermined first fixed value to the first rate of change of the first unit time, the second rate of change in the second unit time is obtained by subtracting a predetermined second fixed value from the second rate of change in the first unit time, The lighting control device is characterized in that the first fixed value and the second fixed value are different from each other.

2. The lighting control device according to claim 1 , wherein the control circuit has a memory that stores the first rate of change per unit time and the second rate of change per unit time.

3. The lighting control device according to claim 1 or 2; the light source unit; A lighting fixture comprising:

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