Lighting device and lighting apparatus

Abstract

To provide a lighting device and an illuminating device that can control fading at changing a dimming rate more appropriately.SOLUTION: A lighting device comprises: a lightning circuit for turning on a light source; and a controller that controls the lightning circuit in response to a signal inputted from the exterior. The lighting device is configured to select one of a fading inclination fixed mode where a fading inclination, which is a rate of change in dimming rate of the light source to a fading time, is constant independently of a difference between dimming rates before and after the change, and a fading inclination variable mode where the fading inclination can be changed so that the fading time is constant independently of the difference between the dimming rates before and after the change.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a lighting device and an illumination device.

Background Art

[0002] For example, Patent Document 1 discloses a dimming control device that uses a fade function to change the dimming rate of a dimmable lighting fixture. According to the fade function, the dimming rate is changed to a desired dimming rate over a certain period of time.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] As methods for realizing the fade function, the following two methods can be considered. The first method is to make the fade slope, which is the rate of change of the dimming rate of the light source with respect to the fade time, constant regardless of the difference in the dimming rate before and after the change. Here, it is referred to as "fixed fade slope". The second method is to make the fade slope variable so that the fade time is constant regardless of the difference in the dimming rate before and after the change. Here, it is referred to as "variable fade slope". Conventional lighting devices are configured to be able to use only one of these two methods.

[0005] As exemplified below, fade slope fixing and fade slope variability each have advantages and disadvantages. For example, in the case of a long fade time setting, fade slope variability has a disadvantage in that the accuracy of dimming rate adjustment is lower than that of fade slope fixing. Therefore, when a plurality of luminaires are batch-controlled by a dimmer and the fade time is set long, if fade slope variability is used, there is a risk of variations in dimming rate control due to errors between the luminaires. On the other hand, for example, when fade slope fixing is used for a luminaire with a dimming and color temperature adjustment function that combines two types of light sources with different color temperatures, there is a risk that the color temperature and the ratio of the dimming rate will collapse during the change of the dimming rate, as compared with the case where fade slope variability is used.

[0006] The present disclosure has been made to solve the above-described problems, and an object thereof is to obtain a lighting device and a lighting apparatus capable of more appropriately controlling the fade when changing the dimming rate.

Means for Solving the Problems

[0007] The Lighting device according to the present disclosure It includes a light source and a lighting device. The light source includes a first light source and a second light source. The lighting device includes a lighting circuit that lights a light source, and a control unit that controls the lighting circuit in response to a signal input from the outside including and has a fade slope variable mode in which the fade slope, which is the change rate of the dimming rate of the light source with respect to the fade time, is made variable so that the fade time becomes constant regardless of the difference in the dimming rate before and after the change. In the fade slope variable mode, the control unit controls the dimming rate of each of the first light source and the second light source so as to reach the target dimming rate at the elapse of the fade time setting value, and when the target dimming rate is updated, controls the dimming rate of each of the first light source and the second light source so as to reach the updated target dimming rate at the elapse of a new fade time setting value starting from the update time of the target dimming rate.

Effects of the Invention

[0008] In the lighting device according to the present disclosure, either a fade slope fixed mode or a fade slope variable mode can be selected. Therefore, it becomes possible to more appropriately control the fade when changing the dimming rate.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Mode for Carrying Out the Invention

[0010] The lighting device and the illumination device according to the present embodiment will be described with reference to the drawings. The same or corresponding components may be denoted by the same reference numerals, and the repeated description may be omitted.

[0011] Embodiment 1. FIG. 1 is a diagram showing the configuration of an illumination device 100 according to Embodiment 1. The illumination device 100 includes a lighting device 2, two light sources 10 and 11, and a dimmer 9. Note that the light sources 10 and 11 respectively correspond to examples of the "first light source" and the "second light source" according to the present disclosure.

[0012] The light source 10 is composed of, for example, one or more light-emitting diodes (LEDs). The light source 11 is composed of, for example, one or more LEDs having a color temperature different from that of the light source 10. In an example where each of the light sources 10 and 11 is composed of a plurality of LEDs, the plurality of LEDs constituting each of the light sources 10 and 11 may be connected in series or in parallel, or may be connected in a combination of series and parallel.

[0013] The light source 10 is unified by, for example, an LED having a color temperature of 5000K, and the light source 11 is unified by, for example, an LED having a color temperature of 3000K. That is, the lighting device 100 includes a lighting fixture with a dimming and color adjustment function having two types of light sources 10 and 11 with different color temperatures. According to such a lighting device 100, by adjusting the brightness of the light sources 10 and 11, combined light with a color temperature ranging from 3000K to 5000K can be produced. Note that the lighting device 100 includes one set of the combination of the light sources 10 and 11 and the lighting device 2, but it may include a plurality of such sets.

[0014] The lighting device 2 includes a lighting circuit 3 and a control circuit 8 that controls the lighting circuit 3. Note that the control circuit 8 corresponds to an example of the "control unit" according to the present disclosure.

[0015] The lighting circuit 3 is connected to the commercial power supply 1. The commercial power supply 1 is an AC power supply or a DC power supply such as a storage battery. The lighting circuit 3 converts the AC power or DC power from the commercial power supply 1 and supplies optimal power to the light sources 10 and 11. As a result, one or both of the light sources 10 and 11 can be lit. The lighting circuit 3 is controlled by the control circuit 8. The lighting circuit 3 is constituted by, for example, one or a plurality of power factor correction (PFC) circuits and a step-down circuit (buck converter) circuit, respectively.

[0016] The control circuit 8 is constituted by, for example, one or a plurality of microcomputers (microcontrollers) or DSP (Digital Signal Processor). An example of the control circuit 8 is shown in FIG. 1. In FIG. 1, the control circuit 8 includes a drive unit 4, a processing unit 5, a storage unit 6, and an A / D conversion unit 7 that are connected to each other.

[0017] The drive unit 4 outputs a drive signal for driving the lighting circuit 3. The drive signal is, for example, a PWM (Pulse Width Modulation) signal. The A / D conversion unit 7 is connected to the lighting circuit 3 and converts the current flowing through the light source 10 or the voltage of the light source 10 into a digital value. Similarly, the A / D conversion unit 7 converts the current flowing through the light source 11 or the voltage of the light source 11 into a digital value. These digital values are input to the processing unit 5. The processing unit 5 performs arithmetic processing using these digital values.

[0018] The processing unit 5 receives a signal from outside the lighting device 2 and controls the drive signal output by the drive unit 4 according to the signal from outside. An example of the outside here is the dimmer 9. The dimmer 9 sends a signal to the processing unit 5. The signal from the dimmer 9 is sent wirelessly or wired. As the signal from the dimmer 9, for example, a PWM signal or a UART (Universal Asynchronous Receiver / Transmitter) signal is used.

[0019] More specifically, the dimmer 9 sends a signal specifying the target dimming rate to the processing unit 5. The control circuit 8 having the processing unit 5 controls the lighting circuit 3 so that the dimming rates of the light sources 10 and 11 respectively become the target dimming rate received from the dimmer 9.

[0020] Furthermore, the lighting device 2 has a fade function for gradually changing the dimming rate toward the target dimming rate. More specifically, the fade function includes a fade-in function for gradually increasing the dimming rate toward the target dimming rate and a fade-out function for gradually decreasing the dimming rate toward the target dimming rate.

[0021] Furthermore, the control circuit 8 of the present embodiment can execute each of the following "fade slope fixed mode" and "fade slope variable mode", and is configured to be able to select either one of these modes. Hereinafter, the change rate of the dimming rate of the light source with respect to the fade time is referred to as the "fade slope". The fade time is the time from the start of the change in the dimming rate to the end of the change in the dimming rate. The fade slope fixed mode is a mode in which the fade slope is made constant regardless of the difference in the dimming rate before and after the change. On the other hand, the fade slope variable mode is a mode in which the fade slope is made variable so that the fade time becomes constant regardless of the difference in the dimming rate before and after the change.

[0022] FIG. 2 is a diagram showing the operation of the fade slope fixed mode according to Embodiment 1. FIG. 2 shows the relationship between the dimming rate and time. As an example, FIG. 2 shows the operation when the fade time set value, which is the set value of the fade time, is 2 seconds. The fade time is set, for example, by a person operating the dimmer 9.

[0023] When the fade time set value is, for example, 2 seconds, according to the fade slope fixed mode, the fade slope ΔDIM / Δt is specified so that the dimming rate changes from 0% to 100% during the elapsed time of the fade time set value of 2 seconds, that is, 2000 ms. The following formula (1) is the calculation formula for the fade slope ΔDIM / Δt in the fade slope fixed mode. 100% in the numerator of formula (1) is a fixed value. Note that the fade slope ΔDIM / Δt takes a positive value when increasing the dimming rate and a negative value when decreasing the dimming rate.

Equation

[0024] As represented by Equation (1), the fade slope ΔDIM / Δt in the fade slope fixed mode takes a value according to the fade time setting value, which is the time required for the dimming rate to change from 0% to 100%. Therefore, as shown in Figure 2, the fade slope fixed mode has the characteristic that the smaller the difference between the dimming rate before the change and the dimming rate after the change, the faster the dimming rate changes. Specifically, in the example where the fade time setting value is 2 seconds, when changing the dimming rate from 0% to 100%, it takes 2 seconds to reach the target dimming rate, but when changing the dimming rate from 50% to 100%, the fade time required to reach the target value is 1 second.

[0025] Next, Figure 3 is a diagram showing the operation of the fade slope variable mode according to Embodiment 1. Figure 3 shows the relationship between the dimming rate and time. As an example, Figure 3 shows the operation when the fade time setting value is 2 seconds, similar to Figure 2.

[0026] As shown in Figure 3, according to the fade slope variable mode, different from the fade slope fixed mode, regardless of the difference in the dimming rate before and after the change, the dimming rate changes in accordance with the fade time setting value. That is, no matter from which value the dimming rate is changed to 100%, the fade slope ΔDIM / Δt is changed so that the fade time required for the change in the dimming rate is 2 seconds when the fade time setting value is, for example, 2 seconds.

[0027] Specifically, in the example where the fade time setting value is 2 seconds, when changing the dimming rate from 0% to 100%, it takes 2 seconds to reach the target dimming rate, and it also takes 2 seconds when changing the dimming rate from 50% to 100%. The following Equation (2) is the calculation formula for the fade slope ΔDIM / Δt in the fade slope variable mode. Also, the calculation example of the fade slope ΔDIM / Δt when the fade time setting value is 2 seconds and the dimming rate is changed from 50% to 100% is as follows. Note that the amount of change in the dimming rate before and after the change in the dimming rate takes a positive value when increasing the dimming rate and a negative value when decreasing the dimming rate. And the sign of the fade slope ΔDIM / Δt is the same as the sign of the amount of change in the dimming rate.

Equation

[0028] In the storage unit 6 of the control circuit 8 shown in FIG. 1, both the above formulas (1) and (2), which are the calculation formulas of the fade slope ΔDIM / Δt in the fade slope fixed mode and the fade slope variable mode, are stored.

[0029] As described above, the control circuit 8 of the present embodiment is configured to be able to select either one of the "fade slope fixed mode" and the "fade slope variable mode". Specifically, the control circuit 8 of the present embodiment selects either one of the fade slope fixed mode and the fade slope variable mode according to a signal input from the outside. In other words, the control circuit 8 is configured to properly use the two types of fade slope fixed mode and fade slope variable mode according to a signal input from the outside.

[0030] An example of the external here is the dimmer 9. Therefore, the control circuit 8 selects either one of the above two modes according to the signal from the dimmer 9. More specifically, the signal sent from the dimmer 9 to the processing unit 5 of the control circuit 8 includes a signal specifying either one of the fade slope fixed mode and the fade slope variable mode. The signal specifying either one of them may be sent simultaneously with the signal specifying the above-mentioned dimming rate, or may be sent separately from the signal specifying the dimming rate. Note that the information transmitted from the dimmer 9 to the processing unit 5 may include a fade time set value and a target dimming rate.

[0031] When the processing unit 5 of the control circuit 8 receives a signal specifying either one of the above two modes, it calculates the fade slope ΔDIM / Δt according to the formula (1) or (2) corresponding to the signal. Then, the control circuit 8 controls the lighting circuit 3 so that the dimming rates of the light sources 10 and 11 become the target dimming rate at the change rate according to the calculated fade slope ΔDIM / Δt.

[0032] Note that the selection of either one of the above two modes may be made, for example, when the formulas (1) and (2) are stored in the storage unit 6, instead of the above example based on the signal from the dimmer 9.

[0033] As already described, the lighting device 100 of the present embodiment has two types of light sources 10 and 11 with different color temperatures, and a dimming and color adjustment function can be realized by controlling these light sources 10 and 11 with the lighting device 2. Specifically, according to the lighting device 2, by adjusting the brightness of the two types of light sources 10 and 11, the color temperature is controlled within the range from 3000K to 5000K, and the dimming rate is controlled within the range from 0% to 100%.

[0034] When the fade function is used in the lighting device 100, the operations in the fade slope fixed mode and the fade slope variable mode have the following characteristics as exemplified and described with reference to FIGS. 4 to 6. In the examples shown in FIGS. 4 to 6, the fade time setting value is assumed to be 2 seconds as an example. Also, in the examples shown in FIGS. 4 to 6, the color temperature and the dimming rate of the combined light by the two types of light sources 10 and 11 are simultaneously changed so as to change from a state of a color temperature of 4000K and a dimming rate of 50% to a state of a color temperature of 5000K and a dimming rate of 100%. For this change, the dimming rate of the light source 10 with a color temperature of 5000K is changed from 25% to 100%, and the dimming rate of the light source 11 with a color temperature of 3000K is changed from 25% to 0%.

[0035] First, FIG. 4 is a diagram showing the operation in the fade slope fixed mode in the lighting device 100 having two types of light sources 10 and 11. Note that the dimming rate of each of the light sources 10 and 11 alone is from 0% to 100%. Here, the dimming rate of the combined light is in the range of 0% to 100% obtained by adding the lights of the light sources 10 and 11. For example, there is no operation of obtaining combined light with a dimming rate of 120% by adding the light of the light source 10 with a dimming rate of 60% and the light of the light source 11 with a dimming rate of 60%. If the dimming rate of the light source 10 is 60%, the dimming rate of the light source 11 operates within the range from a minimum of 0% to a maximum of 40%. Also, the color temperature of the combined light is determined by the ratio of 5000K of the light source 10 and 3000K of the light source 11. For example, when the dimming rate of the light source 10 is 60% and the dimming rate of the light source 11 is 40%, the color temperature of the combined light is 4200K, which is the sum of the product of 5000K and 0.6 and the product of 3000K and 0.4.

[0036] As shown in FIG. 4, the dimming rates of the light sources 10 and 11 before the change are both 25%, and the color temperature and dimming rate of the combined light are 4000K and 50% respectively. When changing the dimming rate of the light source 10 to 100% and the dimming rate of the light source 11 to 0% from this state, since the fade slope ΔDIM / Δt is fixed, the time required to reach the target dimming rate is different between the light source 10 and the light source 11. Specifically, as shown in FIG. 4, the light source 10 takes 1.5 seconds, and the light source 11 takes 0.5 seconds. Thus, if the time required to reach the target dimming rate is different between the light sources 10 and 11, the ratio of the color temperature and dimming rate of the combined light during the change will collapse. As a result, there may arise a problem that a color tone different from the intended color temperature is seen.

[0037] Next, FIG. 5 is a diagram showing the ideal operation in the lighting device 100 having the dimming and color adjustment function. As shown in FIG. 5, the ideal operation is an operation in which the color temperature and dimming rate of the combined light are switched from the state of a color temperature of 4000K and a dimming rate of 50% to the state of a color temperature of 5000K and a dimming rate of 100% in a fade time of 1 second. Additionally, as shown in FIG. 5, it is ideal that the light sources 10 and 11 reach the target dimming rate simultaneously. However, in the example of the fade slope fixed mode shown in FIG. 4, such an ideal operation cannot be obtained.

[0038] Next, FIG. 6 is a diagram showing the operation in the fade slope variable mode in the lighting device 100 having two types of light sources 10 and 11. An operation close to the ideal operation shown in FIG. 5 is realized by using the fade slope variable mode. The fade time setting value in the example described with reference to FIG. 6 is the same 2 seconds as in the example shown in FIG. 4.

[0039] Specifically, when the fade slope variable mode is selected, the control circuit 8 controls the dimming rate of each of the light sources 10 and 11 so as to reach the target dimming rate when the fade time setting value elapses. As a result, as shown in FIG. 6, according to the fade slope variable mode, the dimming rate of the light source 10 with a color temperature of 5000K changes from 25% to 100% over 2 seconds, and the dimming rate of the light source 11 with a color temperature of 3000K changes from 25% to 0% over the same 2 seconds. As a result, the synthesized light changes from a state with a color temperature of 4000K and a dimming rate of 50% to a state with a color temperature of 5000K and a dimming rate of 100% over 2 seconds. By selecting the fade slope variable mode in this way, the color temperature and dimming rate of the synthesized light during the change also become as intended.

[0040] Next, with reference to FIG. 7, the operation regarding the fade slope variable mode is supplemented. FIG. 7 is a diagram showing the operation when a new target dimming rate is set during the change of the dimming rate in the fade slope variable mode in the lighting device 100 having two types of light sources 10 and 11. When the target dimming rate is updated while the control circuit 8 is selecting the fade slope variable mode and changing the dimming rate, the control circuit 8 controls the dimming rate of each of the light sources 10 and 11 so as to reach the updated target dimming rate when the new fade time setting value starting from the time of update of the target dimming rate elapses. In an example shown in FIG. 7, the fade time setting value is set to 3 seconds, and a new target dimming rate is set 1 second after the start of the change of the dimming rate. In this case, as shown in FIG. 7, the control circuit 8 controls the dimming rate of each of the light sources 10 and 11 so as to reach the new target dimming rate when the new fade time setting value of 3 seconds starting from the time of update of the target dimming rate according to the new target dimming rate elapses.

[0041] In the case of the lighting device 100 having the dimming and color temperature adjustment function described above, under the conditions described with reference to FIGS. 4 to 6, it can be said that the fade slope variable mode is more suitable than the fade slope fixed mode. That is, according to the fade slope variable mode, when performing dimming and color temperature adjustment, the color temperature and dimming rate of the combined light during the change can also be made as intended. However, the merits of such a fade slope variable mode are not necessarily always obtained. Specifically, for example, when the amount of change in the dimming rate is small or when the fade time set value is long, the accuracy of adjusting the dimming rate decreases.

[0042] On the other hand, the following can be said about the fade slope fixed mode. That is, according to the fade slope fixed mode, as already described, when performing dimming and color temperature adjustment, the changes in the color temperature and dimming rate of the combined light during the change may not be intentional. However, in the case of being used in the most popular single-color lighting fixtures, the dimming rate can be switched quickly by the fade slope fixed mode. Also, the fade slope fixed mode has the merit that the accuracy of adjusting the dimming rate is better than that of the fade slope variable mode when the fade time is set long. Furthermore, when a plurality of lighting fixtures are collectively controlled by a dimmer, the variation in the dimming rate due to the error between the lighting fixtures can be suppressed.

[0043] As described above, each of the fade slope fixed mode and the fade slope variable mode has merits and demerits. Therefore, the lighting device 2 of the present embodiment is configured to be able to select either the fade slope fixed mode or the fade slope variable mode. As a result, it is possible to obtain a lighting device 2 and a lighting device 100 that can provide a fade function while being less affected by the demerits of each of the fade slope fixed and fade slope variable modes, in other words, while effectively utilizing the merits of each of these two types of modes. As a result, it becomes possible to more appropriately control the fade when changing the dimming rate.

[0044] More specifically, according to the present embodiment, the lighting device 2 has calculation formulas for both of the respective fade slopes ΔDIM / Δt in the fixed fade slope mode and the variable fade slope mode. This leads to the ability to optimally control the fade function when changing the dimming rate. In other words, the degree of freedom in controlling the dimming rate using the fade function can be increased. For example, when collectively controlling a plurality of lighting fixtures with a dimmer, by controlling the dimming rate using the fixed fade slope mode, it is possible to suppress variations in the dimming rate due to errors between the lighting fixtures even if the fade time is long. Also, for example, when the lighting fixture includes a lighting device 100 with a dimming and color temperature adjustment function, by using the variable fade slope mode, it becomes possible to control the dimming rate without disturbing the ratio of the color temperature and the dimming rate of the combined light during the change.

[0045] Embodiment 2. FIG. 8 is a diagram showing the configuration of the lighting device 200 according to Embodiment 2. The lighting device 200 is different from Embodiment 1 in the points described below.

[0046] Specifically, the lighting device 200 includes a lighting device 20, a light source 10, and a dimmer 9. That is, the lighting device 200 includes only one light source 10 with respect to the lighting device 20. The lighting device 20 includes a lighting circuit 30 and a control circuit 80. The lighting circuit 30 is configured to supply optimal power to the light source 10. The lighting circuit 30 is controlled by the control circuit 80. Thus, the lighting device 200 includes a single-color lighting fixture having one type of light source 10. And the lighting device 20 included in the lighting device 200 is configured to be able to select either one of the "fixed fade slope mode" and the "variable fade slope mode" in the same manner as in Embodiment 1.

Description of Reference Numerals

[0047] 1 Commercial power supply, 2 Lighting device, 3 Lighting circuit, 4 Driving unit, 5 Processing unit, 6 Memory unit, 7 A / D conversion unit, 8 Control circuit, 9 Dimmer, 10 Light source, 11 Light source, 20 Lighting device, 30 Lighting circuit, 80 Control circuit, 100 Lighting fixture, 200 Lighting fixture

Claims

A lighting device comprising a light source including a first light source and a second light source, a lighting circuit for lighting the light source, and a control unit for controlling the lighting circuit in response to a signal input from the outside, the lighting device having a fade slope variable mode in which a fade slope, which is a rate of change of a dimming rate of the light source with respect to a fade time, is made variable so that the fade time is constant regardless of a difference in dimming rate before and after the change, comprising: In the fade slope variable mode, the control unit controls the dimming rate of each of the first light source and the second light source so as to reach a target dimming rate at the elapse of a fade time setting value, and when the target dimming rate is updated, the control unit controls the dimming rate of each of the first light source and the second light source so as to reach the updated target dimming rate at the elapse of a new fade time setting value starting from the time point of the update of the target dimming rate. An illumination device characterized by the above. According to claim 2, the lighting device is configured to be able to select either one of the fade slope variable mode and a fade slope fixed mode in which the fade slope is made constant regardless of a difference in dimming rate before and after the change. The lighting device according to claim 1, characterized in that. According to claim 3 The control unit is characterized in that, in response to a signal input from the outside, the control unit selects either one of the fade slope fixed mode and the fade slope variable mode. The lighting device according to claim 2, characterized in that. According to claim 4 The outside is a dimmer that sends a signal specifying the dimming rate of the light source to the control unit, The signal sent from the dimmer to the control unit includes a signal specifying either one of the fade slope fixed mode and the fade slope variable mode. The lighting device according to claim 3, characterized in that.

Images