JP2011113793A - Led lighting device and lighting system - Google Patents

Abstract

Provided is an LED lighting device capable of dimming a light emitting diode by PWM control and capable of being formed at low cost, and capable of suppressing a change in luminance at the time of dimming transition of the light emitting diode from being a rough digital change.
An LED lighting device 1 receives a light source 2 configured by combining groups A1 and A2 of light emitting diodes 6 and a PWM signal, and adjusts the light emitting diodes 6 for each group A1 and A2 according to the PWM signal. When a PWM signal for changing the dimming level of the light emitting diodes 6 and the plurality of drive circuits 3 formed so as to be lit is output, the PWM signal after the change and an on-state between the on-duty before and after the change The PWM control circuit 4 is configured to allocate and output a PWM signal having a duty or a PWM signal before the change to the drive circuit 3.
[Selection] Figure 1

Description

The present invention relates to an LED lighting device and a lighting device for dimming and lighting a light emitting diode.

Lighting devices that use light-emitting diodes as light sources are used, for example, for lighting for stage and studio productions, and PWM (pulse width modulation) control is used to perform dimming control without changing the color temperature characteristics. (See, for example, Patent Document 1).

However, the dimming control by the PWM control is the control of the lighting time and light-off time of the light-emitting diode, so that the luminance change of the light-emitting diode becomes crisp and digital and may appear to flicker. This phenomenon is particularly noticeable in a low gradation state with low luminance. In addition, this phenomenon can be solved by reducing the PWM duty. In this case, however, a highly functional microcomputer (CPU) is required, so that the lighting device is expensive.

In view of this, there has been proposed a light control device that aims to light-up the light emitting diode without causing flickering and to reduce the cost (see Patent Document 2). The dimming device of this Patent Document 2 includes a dimmer that generates a dimming signal of a light emitting diode, a control signal generator that generates a PWM control signal and an analog control signal based on the dimming signal, a PWM control signal, LED control unit that controls the current that flows in the light emitting diode based on the analog control signal, and the discontinuity of the current that flows in the light emitting diode between the gradually changing duty can be complemented by the analog current In other words, the control capable of expanding the dimming range without causing flickering can be performed at low cost.

Also, a backlight device has been proposed that can prevent the occurrence of uneven brightness and flicker even when the drive control of the light emitting diode is performed using PWM dimming (Patent Document 3). In the backlight device of Patent Document 3, two adjacent LED light emitting control units are arranged in a predetermined arrangement direction, and the two adjacent light emitting diodes are shifted in the on / off phase of PWM dimming. By turning on the light emitting diodes, the user can visually recognize that all the light emitting diodes are always on in front of the light emitting surface.

JP 2006-40872 A (page 7, FIG. 1) JP 2008-210536 A (pages 5 to 7, FIGS. 1, 4, and 5) JP 2008-198430 A (6th page, FIGS. 1 to 3)

Since the light control device of Patent Document 2 performs analog control between the duty ratios of PWM signals, it is necessary to provide an analog control circuit such as an analog control unit or an analog signal generation unit so as to supply an analog current to the light emitting diode. As a result, the circuit configuration is complicated and expensive.

In addition, the backlight device of Patent Document 3 requires a control to output a PWM signal at the timing of the phase difference by measuring the delay time for shifting the on / off phase of PWM dimming with a timer, and so on. These parts have the disadvantages of high functionality, complicated circuit configuration, and high cost.

The present invention provides an LED lighting device and an illumination device that can dimming a light emitting diode by PWM control, can be formed at low cost, and can suppress a change in luminance at the time of dimming transition of the light emitting diode from being a rough digital change. The purpose is to do.

The invention of the LED lighting device according to claim 1 is a light source configured by combining groups of light-emitting diodes; and is associated with each group of light-emitting diodes, receives a PWM signal, and according to the PWM signal A plurality of drive circuits formed so that the light emitting diodes are dimmed for each group; each drive of a PWM signal having an on-duty corresponding to the dimming level of the light source in accordance with a dimming signal input from the outside; When outputting a PWM signal for changing the dimming level of the light source separately to the circuit, the PWM signal after the change and the PWM that is an intermediate on-duty between the on-duty before and after the change A PWM control circuit configured to allocate and output a signal or a PWM signal before the change to each drive circuit. And wherein the door.

In the present invention and each of the following inventions, each configuration is as follows unless otherwise specified.

The dimming signal input to the PWM control circuit from the outside may be a digitized signal such as a DMX signal or an analog signal such as a voltage value signal. Further, it may be a PWM signal. When the dimming signal other than the PWM signal is input, the PWM control circuit generates an on-duty PWM signal corresponding to the dimming degree of the dimming signal and outputs it to the drive circuit. Here, the dimming degree of the dimming signal corresponds to the dimming level of the light emitting diode.

The on-duty of the PWM signal indicates a ratio of the on period to the total period of the on period and the off period (one period of the PWM signal).

The drive circuit is configured to receive a PWM signal having an on-duty intermediate between the on-duty before and after the change of the dimming level, or the PWM signal before the change of the dimming level. Divided into groups to enter. Further, the latter group may be divided into a plurality of groups each receiving PWM signals having different on-duties.

Further, the drive circuit may be formed so that the light source is turned on during the off-duty period by means of providing an inversion circuit or the like.

The PWM control circuit outputs synchronized PWM signals to a plurality of drive circuits.

According to the present invention, when the PWM control circuit changes the dimming level of the light-emitting diode according to the external dimming signal, the PWM signal after the change of the dimming level and before and after the change of the dimming level are changed. Since a PWM signal having an on-duty in the middle of each on-duty or a PWM signal before the change of the dimming level is assigned to a plurality of drive circuits and output, the light emitting diode is changed after the change of the dimming level. The light is divided into a group that is lit at a dimming level and a group that is lit at an intermediate dimming level before and after the change or a dimming level before the change. Thereby, the luminance change at the time of transition of the light control level of the light emitting diode is not a rough digital change but a smooth change.

The invention of the LED lighting device according to claim 2 is a light source configured by combining groups of light emitting diodes; and is associated with each group of light emitting diodes, and receives a PWM signal, and according to the PWM signal A plurality of drive circuits formed so that the light emitting diodes are dimmed for each group; each drive of a PWM signal having an on-duty corresponding to the dimming level of the light source in accordance with a dimming signal input from the outside; When outputting a PWM signal that is individually output to the circuit and changes the dimming level of the light source, the PWM signal after the change and the rise of the on-duty of the PWM signal after the change are set to 1 of the PWM signal. The change output from the off-duty period so that the falling of the on-duty coincides with the end of the one cycle that is the beginning of the cycle Characterized in that it comprises a; and PWM control circuit and the PWM signal is formed so as to output distributed to each driver circuit having the same on-duty and the PWM signal.

The rise of the on-duty of the PWM signal means the start time of the on-duty period, and the fall means the end time of the on-duty period.

The drive circuit is divided into two groups. When the dimming level of the light emitting diode is changed, one of the PWM signals starts from the on-duty period within one cycle period, and the other is off-duty within one cycle period. A PWM signal starting from the period is input.

According to the present invention, when the dimming level of the light emitting diode is changed in accordance with an external dimming signal, the PWM control circuit has an on-duty of the PWM signal after the change of the dimming level. Since the PWM signal starting from the on-duty within the period and the PWM signal starting from the off-duty are distributed to the plurality of drive circuits and output, the group that lights up with the former PWM signal in one period of the PWM signal The period during which one of the light emitting diodes of the latter group and the light emitting diodes of the group that is turned on by the latter PWM signal is lit up becomes longer. In particular, in the dimming region where the dimming level is low, the on-duty period within one period of the PWM signal is doubled, and the lighting period during which one of the light emitting diode groups is lit is doubled. This makes it difficult to understand the luminance change when the light control level of the light emitting diode is shifted.

According to a third aspect of the present invention, there is provided a dimming device that transmits a dimming signal; a PWM control circuit that outputs a PWM signal having an on-duty in accordance with the dimming degree of the dimming signal transmitted from the dimming device; The LED lighting device according to claim 1 or 2 generated by the method described above; and an LED lighting device having a device main body in which a light source of the LED lighting device is disposed.

The LED lighting device may be disposed in the instrument main body, and the remainder other than the light source may be separately provided from the instrument main body.

The dimming device may transmit the dimming signal either by wire or wirelessly. In the case of wireless, a transmitter is provided in the dimmer and a receiver is provided in the PWM controller.

ADVANTAGE OF THE INVENTION According to this invention, while being able to change the light control level of the light source of a LED lighting fixture from a light control apparatus with a PWM signal, the brightness change at the time of the change of the changed light control level is smooth, and an illuminating device which is hard to understand Provided.

According to the first aspect of the present invention, when the dimming level of the light emitting diode is changed to shift to the dimming level after the change, the light emitting diode constituting the light source is a group that lights at the dimming level after the change. Because the lighting control is divided and controlled according to the middle dimming level before and after the change or the group that lights at the dimming level before the change, it can be formed at a low cost with a simple control configuration, and the dimming level of the light emitting diode The luminance change at the time of the transition can be a smooth digital change, making it difficult for a person to recognize the luminance change.

According to the second aspect of the present invention, when the dimming level of the light emitting diode is changed to shift to the dimming level after the change, the light emitting diode constituting the light source is changed from on-duty within one period of the PWM signal. Since the group that is lit by the PWM signal that starts and the group that is lit by the PWM signal that starts from off-duty are also lit, the period during which one of the light-emitting diodes in the light source is lit becomes long, so it is simple The lighting control configuration can be formed at low cost, and it is possible to make it difficult to understand the luminance change at the time of transition of the light control level of the light emitting diode, thereby making it difficult for a person to recognize the luminance change.

According to the invention of claim 3, by transmitting a dimming signal from the dimming device, the dimming level of the light source of the LED lighting apparatus can be changed by the PWM signal, and the transition of the changed dimming level It is possible to provide an illumination device that can make it difficult for a person to recognize a change in luminance at the time.

The schematic block diagram of the LED lighting device which shows Example 1 of this invention. Similarly, the timing diagram which shows the control of the PWM control circuit in the change of the light control level. The timing diagram which shows the control of the PWM control circuit in the change of the light control level of the LED lighting device which shows Example 2 of this invention. The schematic block diagram of the illuminating device which shows Example 3 of this invention. Similarly, the schematic front view of a light source. Similarly, the schematic front view of LED lighting fixtures. Similarly, the schematic sectional side view of an LED lighting fixture.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

In the present invention, the light source is configured by combining a group of light emitting diodes, and the plurality of driving circuits are associated with each group of the light emitting diodes, and the light emitting diodes are assigned to the respective groups according to the input PWM signal. Turn on the dimmer. The PWM control circuit outputs a PWM signal that changes the dimming lighting level or timing for each group of light emitting diodes to the drive circuit when the dimming level of the light source is shifted to the dimming level after the change. .

1 and 2 show Embodiment 1 of the present invention, FIG. 1 is a schematic block diagram of an LED lighting device, and FIG. 2 is a timing diagram showing control of a PWM control circuit in changing a dimming level.

In FIG. 1, the LED lighting device 1 includes a light source 2, a plurality of drive circuits 3, a PWM control circuit 4, and further includes a DC power supply circuit 5.

The light source 2 is configured by combining the groups A1 and A2 of the light emitting diodes 6. The groups A1 and A2 include LED circuits in which a plurality of light emitting diodes 6 are connected in series and mounted on a substrate (not shown). The light emitting diode 6 is formed to emit visible light, for example, white light.

The drive circuit 3 is provided in association with each of the groups A1 and A2 of the light emitting diodes 6. The drive circuit 3 is formed mainly by the control unit 7 and is connected to the light emitting diodes 6 connected in series with the light source 2. The drive circuit 3 is supplied with power from the DC power supply circuit 5.

The control unit 7 receives the PWM signal output from the PWM control circuit 4 and turns on the output of the drive circuit 3 over an on-duty period of the PWM signal. As a result, the light-emitting diode 6 is dimmed by the current supplied from the drive circuit 3 for each group during the on-duty period of the PWM signal. As the on-duty (on-duty ratio) of the PWM signal increases, the period during which current flows through the light-emitting diode 6 becomes longer, so that the dimming level (dimming rate) of the light-emitting diode 6 increases. That is, the dimming level of the light emitting diode 6 is 0% when the on-duty of the PWM signal is 0%, and 100% when the on-duty of the PWM signal is 100%.

The drive circuit 3 is divided into a group B1 for inputting the PWM signal A from the PWM control circuit 4 and a group B2 for inputting the PWM signal B. Each drive circuit 3 in the group B1 is associated with the group A1 of the light emitting diodes 6 and controls the lighting of the light emitting diodes 6 in the group A1. Each drive circuit 3 in group B2 is associated with group A2 of light emitting diodes 6 and controls lighting of light emitting diodes 6 in group A2. That is, the light-emitting diodes 6 of the group A1 are dimmed and lit based on the PWM signal A, and the light-emitting diodes 6 of the group A2 are dimmed and lit based on the PWM signal B.

The DC power supply circuit 5 is connected to each drive circuit 3 and supplies power to each drive circuit 3. The DC power supply circuit 5 is, for example, a rectifying / smoothing circuit obtained by rectifying and smoothing a commercial AC power supply, or a DC power supply circuit obtained by rectifying or rectifying and smoothing a commercial AC power supply and connected to the step-up chopper circuit, the step-down chopper circuit, or the step-up / step-down chopper circuit. It can be. The DC power supply circuit 5 may be a constant voltage source or a constant current source.

The PWM control circuit 4 is connected to a DC power supply circuit 5 and is operated by electric power supplied from the DC power supply circuit 5. The PWM control circuit 4 receives a dimming signal output from an external dimming device (not shown), and has an on-duty (on-duty ratio) corresponding to the dimming degree (0 to 100%) of the dimming signal. The PWM signal is generated based on the PWM generation clock, and is output to the drive devices 3 of the groups B1 and B2 as PWM signals A and B, respectively. Here, the dimming degree of the dimming signal corresponds to the dimming level of the light emitting diode 6. The dimming signal A and the dimming signal B are output in synchronization, and are output, for example, for 32 cycles (one cycle time 0.625 mS) within one cycle time (for example, 20 ms) of the dimming signal.

Then, when the dimming degree of the input dimming signal is changed, the PWM control circuit 4 generates a PWM signal having an on-duty (on-duty ratio) corresponding to the changed dimming degree, and after the change The PWM signal and the PWM signal before the change are distributed to the groups B1 and B2 of the drive circuit 3 and output. For example, the PWM signal after the change is individually output to each drive circuit 3 of the group B1 as the PWM signal A, and the PWM signal before the change is individually output to each drive circuit 3 of the group B2 as the PWM signal B. .

The output control of the PWM signal by the distribution is executed when the dimming level of the light emitting diode 6 is changed. That is, when the PWM control circuit 4 generates a PWM signal for changing the dimming level of the light emitting diode 6 from, for example, dimming level 1 to dimming level 2 in accordance with the input dimming signal, as shown in FIG. The PWM signal corresponding to the dimming level 2 that is the dimming level after the change is output to the driving circuit 3 of the group B1 over one cycle time (for example, 20 ms) of the dimming signal, and is output to the driving circuit 3 of the group B2. The PWM signal corresponding to the dimming level 1 that is the dimming level before the change is output for, for example, 16 cycles over the first half of one cycle time of the dimming signal, and the dimming level 2 that is the dimming level after the change For example, 16 PWM cycles are output over the latter half of one cycle time of the dimming signal.

When a PWM signal for changing the dimming level of the light emitting diode 6 from, for example, the dimming level 2 to the dimming level 3 is generated, the PWM signal corresponding to the dimming level 3 is dimmed to the drive circuit 3 of the group B1. The signal is output for one cycle time (for example, 20 ms), and the PWM signal corresponding to the dimming level 2 is output to the drive circuit 3 of the group B2 for, for example, 16 cycles over the first half of the cycle time of the dimming signal. The PWM signal corresponding to the dimming level 3 is output, for example, for 16 cycles over the latter half of one cycle time of the dimming signal. Here, the dimming level 1 to the dimming level 3 indicate arbitrary levels at which the dimming level of the light emitting diode 6 gradually increases.

If the dimming level of the light-emitting diode 6 is decreased, for example, the PWM signal corresponding to the decreased dimming level after the change is supplied to the drive circuit 3 of the group B1, as in the description of FIG. The PWM signal corresponding to the dimming level before the change is output to the drive circuit 3 of the group B2 over the first half of the one cycle time of the dimming signal, for example, 16 cycles. The PWM signal corresponding to the dimming level after the change is output for 16 cycles, for example, over the latter half of one cycle time of the dimming signal. Further, the PWM signal before the change may be replaced with a PWM signal having an on-duty intermediate between the on-duty before and after the change.

Next, the operation of the first embodiment of the present invention will be described.

The PWM control circuit 4 of the LED lighting device 1 generates a PWM signal having an on-duty (on-duty ratio) corresponding to the dimming level of the light-emitting diode 6 according to the dimming signal input from the external dimming device. Then, it outputs to each drive circuit 3 of group B1, B2. Thereby, the light emitting diode 6 is dimmed and lit at a dimming level corresponding to the dimming signal. From the light emitting diode 6, visible light (white light) corresponding to the dimming level is emitted.

Then, when a dimming signal for changing the dimming level of the light emitting diode 6 is input, the PWM control circuit 4 generates the changed PWM signal and supplies the changed PWM signal to the drive circuit 3 of the group B1. For example, the signal is output over one cycle period of the dimming signal, and the PWM signal before change is output to the drive circuit 3 of the group B2, for example, over the first half of one cycle period of the dimming signal, and then the PWM signal after change is adjusted. The optical signal is output over the latter half of one cycle period. As a result, the light emitting diodes 6 of the group A1 are lit at the changed dimming level over one cycle period of the dimming signal, and the light emitting diodes 6 of the group A2 are in the first half of the one cycle period of the dimming signal. Lights up at the dimming level, and lights up at the changed dimming level in the second half of one cycle period of the dimming signal.

In the light source 2, since the dimming level of the light-emitting diodes 6 of the group A2 changes step by step when the dimming level shifts, the luminance change of the light-emitting diodes 6 as a whole is smooth and not a rough digital change. It becomes a digital change. Therefore, it is possible to make it difficult for a person to recognize the luminance change of the light source 2 when the dimming level of the light emitting diode 6 is changed.

Further, at the time of transition of the dimming level, the light emitting diode 6 is controlled to be lit separately by the group A1 that is lit at the dimming level after the change and the group A2 that is lit at the dimming level before the change. With the control configuration, the LED lighting device 1 can be formed at low cost.

In the LED lighting device 1, the light source 2 is divided into groups A1 and A2 of the light-emitting diodes 6 and the plurality of driving circuits 3 are divided into groups B1 and B2. The circuits 3 may be divided into three or more groups. Then, the PWM control circuit 4 outputs the PWM signal after the change to the drive circuit 3 of one group, and the PWM signal having an on-duty intermediate between the on-duty before and after the change to the drive circuit 3 of the remaining group or The PWM signal may be assigned to the drive circuit 3 and output so as to be output differently from the PWM signal before the change.

FIG. 3 is a timing chart showing the control of the PWM control circuit in changing the dimming level of the LED lighting device according to the second embodiment of the present invention.

The LED lighting device that performs the control shown in FIG. 3 has the same configuration as the LED lighting device 1 shown in FIG. 1, and only the control of the PWM control circuit 4 is different. When the PWM control circuit 4 outputs a PWM signal for changing the dimming level of the light emitting diode 6 according to the dimming signal from the external dimming device, the PWM control circuit 4 outputs the changed PWM signal and the changed PWM signal. The on-duty (on-duty) that is the same as the PWM signal after the change that is output from the off-duty period so that the on-duty rise coincides with the end of the one cycle, where the on-duty rise is the beginning of one cycle of the PWM signal. The PWM signal having a ratio) is distributed to the drive circuits 3 of the groups B1 and B2 and output. That is, they have the same on-duty (on-duty ratio), and are configured to output a PWM signal starting from the on-duty period and a PWM signal starting from the off-duty period in synchronization.

For example, as shown in FIG. 3, when a PWM signal for changing the dimming level of the light emitting diode 6 from, for example, the dimming level 1 to the dimming level 4 is generated, the dimming level 1 is provided to each drive circuit 3 in the group B1. A PWM signal starting from an on-duty period having an on-duty (on-duty ratio) of dimming level 2, dimming level 3 and dimming level 4 is output as PWM signal A, for example, for eight periods, and each group B2 Similarly, a PWM signal starting from the off-duty period is output to the drive circuit 3 as a PWM signal B for 8 cycles.

The light-emitting diodes 6 in group A1 are lit at dimming levels 1 to 4 over the on-duty period in the first half of one cycle period of the PWM signal, and the light-emitting diodes 6 in group A2 are turned on in the second half of one cycle period of the PWM signal. The light is lit at dimming levels 1 to 4 over the duty period, and is lit in steps from dimming level 1 to dimming level 4 over one period of the dimming signal. As a result, the light source 2 as a whole is controlled such that the lighting period of the light emitting diode 6 in one cycle period of the PWM signal is long, the extinguishing period is short, and the dimming level changes stepwise. Therefore, the luminance change of the light emitting diode 6 is not a rough digital change but a smooth digital change. Therefore, when the dimming level of the light emitting diode 6 is changed, it is possible to make it difficult for a person to understand the luminance change of the light source 2.

In particular, in the dimming region where the dimming level is low, the luminance change of the light emitting diode 6 due to the dimming level difference before and after the change of the dimming level appears noticeably visually. Here, in the dimming region where the dimming level is low, the total on-duty period in one period of the PWM signal is doubled, and there is a lighting period in which one of the groups A1 and A2 of the light emitting diodes 6 is lit. Since it becomes twice, it is possible to make the change in luminance more difficult to understand when the light control level of the light emitting diode 6 is shifted. Since the PWM control device 4 has a simple configuration for performing the control operation, the LED lighting device 1 can be formed at low cost.

4 to 7 show a third embodiment of the present invention, FIG. 4 is a schematic block diagram of a lighting device, FIG. 5 is a schematic front view of a light source, FIG. 6 is a schematic front view of an LED lighting apparatus, and FIG. It is a schematic sectional side view of a lighting fixture. Note that the same parts as those in FIG.

As shown in FIG. 4, the lighting device 8 includes a light control device 9, an LED lighting device 1 and an LED lighting device 10 shown in FIG. 1.

The light control device 9 is, for example, a light control table, and transmits a DMX signal, which is a light control signal with 256 gradations, for example. This DMX signal is a digital signal used in a production field or the like standardized by the American Theater Technology Association (USITT), and indicates the DMX 512 used as a standard of a dimming signal for dimming control. The dimmer 4 transmits the DMX signal at a period of, for example, 20 milliseconds (ms).

The LED lighting apparatus 10 includes an apparatus main body 11 in which the light source 2 is disposed. As shown in FIG. 7, the LED lighting fixture 10 is configured, for example, as a spotlight, and the fixture main body 11 includes a light source unit 12 and a lens unit 13. From the light source unit 12, the emitted light of the light emitting diode 6 is emitted. The lens unit 13 includes projection lenses 14a and 14b that collect light and project the light outside. As shown in FIG. 6, the light emitted from the light source unit 12 is transmitted through the light transmitting portion 15 provided in front of the lens unit 13 and projected onto the illumination target. And the instrument main body 11 is attached to the arm 16 attached to constructions, such as a ceiling, so that a projection direction can rotate freely.

In FIG. 7, the light source unit 12 includes a light source 2 that is a planar light source, and heat generated in the light source 2 is radiated to an external space by a radiator (not shown). The light source unit 12 includes a power supply unit 17 that supplies lighting power to the light source 2, a control unit 18 that controls lighting of the light source 2, and a cylindrical optical path 19. The power supply unit 17 is provided with the drive circuit 3 and the DC power supply circuit 5 of the LED lighting device 1 shown in FIG. In the control unit 18, the PWM control circuit 4 is formed by electronic components mounted on the circuit board 20. A transmission line (not shown) is connected to the circuit board 20, and the control unit 18 inputs a dimming signal transmitted from the dimming device 9 through the transmission line. The cylindrical optical path 19 guides light from the light source 2 to the lens unit 13.

As shown in FIG. 5, the light source 2 has a plurality of chip-like light emitting diodes 6 mounted on a flat printed board 21. The light emitting diode 6 that emits white light is used. A light emitting diode 6 that emits red, green, and blue light may be used for complementary colors.

The light source 2 includes a plurality of light emitting diodes 6 connected in series and is grouped into a plurality of LED circuits 22 arranged in a rectangular shape. The plurality of LED circuits 22 are configured such that the light emission area approximates the virtual circle 23 by combining a plurality of LED circuits 22.

The light source 2 is grouped into ten LED circuits 24a to 24j. Each LED circuit 24a-24j has power supply terminals 25a-25j individually, and lighting power is supplied to the power supply terminals 25a-25j from the power supply unit 17 by lighting control of the control unit 18, and each LED circuit The light emitting diodes 6a to 24j are lit.

Each of the LED circuits 24a to 24j is formed by arranging a plurality of light emitting diodes 6 in a rectangular shape, but is classified into three types in which the plurality of light emitting diodes 6 are arranged in a rectangular shape having a different size. Yes. Each of the LED circuits 24a to 24j has the same rectangular short side length, and seven light emitting diodes 6 are connected in series in the short side direction, and the series-connected circuits are parallel in groups. It is connected. The LED circuits 24c and 24h at the center of the light source 2 are the longest group having the longest rectangular side, and the LED circuits 24a, 24e, 24f and 24j at both ends have the shortest long rectangular side. LED circuits 24b, 24d, 24g, and 24i in the middle portion between the longest group and the shortest group are intermediate groups having a rectangular long side having an intermediate length. The LED circuit 24a, 24c, 24e, 24g, 24i forms the group A1 of the light emitting diodes 6 shown in FIG. 1 or FIG. 4, and the LED circuit 24b, 24d, 24f, 24h, 24j forms the group of the light emitting diodes 6 A2 is formed.

Since the illuminating device 8 includes the LED lighting device 1, the illuminating device 8 can be formed at low cost, and the dimming level of the light source 2 of the LED lighting device 10 is set to a PWM signal by the dimming signal transmitted from the dimming device 9. In addition, the luminance change at the time of changing the dimming level can be difficult to understand, and can be difficult for humans to recognize.

INDUSTRIAL APPLICABILITY The present invention can be used for a lighting device for dimming a room or the like in addition to a lighting device for effecting lighting a stage or a studio.

DESCRIPTION OF SYMBOLS 1 ... LED lighting device, 2 ... Light source, 3 ... Drive circuit, 4 ... PWM control circuit, 6 ... Light emitting diode, 8 ... Illuminating device, 9 ... Dimming device, 10 ... LED lighting fixture

Claims (3)

A light source configured by combining groups of light-emitting diodes; formed to be associated with each group of light-emitting diodes, to input a PWM signal, and to dimm the light-emitting diodes for each group according to the PWM signal A plurality of drive circuits; and a PWM signal having an on-duty corresponding to the dimming level of the light source according to a dimming signal input from the outside, individually output to each drive circuit, When outputting a PWM signal that changes the dimming level, each of the drive circuits includes the PWM signal after the change and a PWM signal that is an on-duty intermediate between the on-duty before and after the change or the PWM signal before the change. An LED lighting device comprising: a PWM control circuit configured to be assigned and output. A light source configured by combining groups of light-emitting diodes; formed to be associated with each group of light-emitting diodes, to input a PWM signal, and to dimm the light-emitting diodes for each group according to the PWM signal A plurality of drive circuits; and a PWM signal having an on-duty corresponding to the dimming level of the light source according to a dimming signal input from the outside, individually output to each drive circuit, When outputting a PWM signal for changing the dimming level, the duty cycle of the PWM signal after the change and the on-duty rise of the PWM signal after the change is set to the start of one cycle of the PWM signal. The same on-duty as the PWM signal after the change that is output from the off-duty period so that the falling edges of the And a PWM control circuit configured to distribute and output the PWM signal to each drive circuit. 3. A dimming device for transmitting a dimming signal; and an LED lighting according to claim 1 or 2, wherein a PWM control circuit generates a PWM signal having an on-duty in accordance with the dimming degree of the dimming signal transmitted from the dimming device. And an LED lighting fixture having a fixture main body in which a light source of the LED lighting device is disposed.

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