JP7143358B2 - lighting equipment - Google Patents

Description

The present invention primarily relates to a dimmable LED lighting device.

With the spread of LED lighting using small-sized LEDs, it has become possible to easily realize a dimming and toning lighting device that freely changes colors by mixing two or three colors of LEDs. Dimmable color lighting equipment mimics the changes in the colors of the natural world, such as the bluish white light of the blue sky during the day and the red light of the setting sun in the evening. It is thought that it can contribute to improving the efficiency of the body, relaxing, and improving the quality of sleep, which in turn contributes to improving human health.

As a method of toning, it is common to use two white light sources with a high color temperature and a low color temperature and change the ratio of their brightness, but there is also an example of using three light sources. FIG. 7 discloses a dimming toning lighting device for toning within a chromaticity coordinate surrounded by LEDs of three colors (BSY1, BSY2, R, where BSY stands for blue, shifted yellow, and yellow).

Dimming methods for adjusting the brightness of LED lighting include an analog control method that changes the current value supplied to the LED, and a PWM (Pulse Width Modulation) control method that controls the pulse width supplied to the LED. Widely used. In Patent Document 2, in order to provide an LED lighting fixture that is dimmed in proportion to a dimming signal that is generally used for incandescent lamps, etc., the value of the dimming level (a) is determined by the VI characteristics of the LED element. In areas brighter than the dimming level (a), dimming is performed by changing the set current of the constant current circuit (DC dimming mode), and in areas darker than the dimming level (a), the constant current circuit is fixed, the transistor is turned ON/OFF, and the DUTY is changed to perform dimming (DUTY dimming mode). More specifically, the dimming level (a) is defined as ΔV/ΔI at the rated current of the LED element as A, and as the current flowing through the LED element is lowered, ΔV/ΔI (=B) is If the value of B becomes 3 to 5 times the value of A, the LED element will become unstable and the variation will increase. , the dimming level (a) is set.

In Patent Document 3, a first LED load and a second DC/DC voltage conversion circuit are connected to the output side of the first DC/DC voltage conversion circuit, and the output side of the second DC/DC voltage conversion circuit An LED drive circuit that connects a second LED load, with respect to the reference voltage Vref corresponding to the current command value, analog control is performed when the voltage level is between Va (maximum value) and Vb, and below Vb, Duty is controlled by variable pulse width. Since the LED current IL itself is an analog value, a second DC/DC voltage conversion circuit can be connected to the LED load side of the first DC/DC voltage conversion circuit.

In Patent Document 4, when the current supplied to the LED lighting device is a pulse containing a ripple synchronized with the oscillation frequency of the switching power supply or the PWM frequency for dimming, the LED lighting device having two LED arrays For the illuminated barcode, the blinking timings of the optical outputs O1 and O2 of the two LED arrays are shifted by a wavelength of λ/2 in order to avoid barcode reading failure.

U.S. Pat. No. 8,598,809 JP 2009-123681 JP 2007-189004 JP 2014-38826

In light control of LEDs, in the case of a method of controlling the current value applied to the LED (analog control method), there is a problem that the accuracy of control deteriorates as the output decreases.

On the other hand, in the case of the PWM method in which LED dimming is controlled by the pulse width, there is a problem that it is difficult to read two-dimensional barcodes such as barcodes and QR codes (registered trademark) under lighting conditions. When these codes are read by illumination using pulsed light controlled by PWM, the effects of flashing at a speed invisible to the human eye make it difficult for barcode readers and cameras to recognize them, resulting in barcodes and two-dimensional barcodes. It is thought that this is because it becomes difficult to read the

In the midst of such problems, it is also necessary to examine how to specifically control the analog control method and the pulse control method. Furthermore, when a plurality of LEDs are used for dimming and color adjustment, the relationship between the pulses of the plurality of LEDs has not been studied from the viewpoint of barcode reading.

An object of the present invention is to improve the accuracy of dimming and color adjustment control and to prevent reading failures of barcodes and two-dimensional barcodes in an LED lighting device using a plurality of light sources of different colors. That is.

The present invention is a lighting device capable of controlling the light output of a light source of a plurality of colors, wherein control for generating a high-output control signal and a low-output control signal from a color-specific control signal transmitted from the outside for each color. and a drive circuit that generates a drive output based on the high power control signal and the low power control signal, wherein the high power control signal is a PWM signal or a PFM signal that controls an analog value of the drive output. The high-output control signal changes in accordance with a change in the color-specific control signal when the color-specific control signal controls the output side above the boundary output, and the color-specific control signal changes according to the boundary output. When the output below the output is controlled, it does not change according to the change of the color-specific control signal, and the low output control signal is a signal for controlling the pulse shape of the drive output . The control signal does not change in response to a change in the color-specific control signal when the color-specific control signal controls the output side above the boundary output, and the color-specific control signal controls the output below the boundary output. In the lighting device, when controlled, the drive output generated for each color is output to the light source of each color.

In the present invention, it is preferable that the drive output is an analog output on the high output side above the boundary output and a pulse output on the low output side of the boundary output.

In the present invention, the high power control signal is preferably a pulse signal.

In the present invention, the low output control signal is preferably a PWM signal or a PFM signal on the low output side of the boundary output.

In the present invention, it is preferable that the plurality of driving outputs are not synchronized with each other on the lower output side than the boundary output.

The present invention provides a lighting device capable of controlling the light output of a light source of a plurality of colors, comprising: a control circuit for generating an output control signal from a color-specific control signal transmitted from the outside for each of the colors; wherein the output control signal controls the analog value of the drive output on the high output side above the boundary output and the pulse shape of the drive output on the low output side below the boundary output wherein the drive output is an analog output on the high output side of the boundary output or more, and is a pulse output on the low output side of the boundary output, and the plurality of drive outputs are the pulse outputs and wherein the driving outputs generated for each of the colors are respectively output to the light sources of the respective colors.

In the present invention, it is preferable that the illumination device has light sources of three or more colors.

In the present invention, it is preferable that the three or more color light sources include a red LED, a yellowish white LED, and a bluish white LED.

In the present invention, the chromaticity of the emission color of the yellow-white LED package is (0.423, 0.355), (0.34, 0.28), (0.352, 0) in the CIE1931 chromaticity coordinate system. .44), (0.37, 0.63) and the chromaticity in the range enclosed by the chromaticity boundary line.

In the present invention, the chromaticity of the emission color of the blue-white LED package is (0.34, 0.28), (0.352, 0.44), (0.18, 0.18, 0.44) in CIE1931 chromaticity coordinates. 24), preferably within the chromaticity range enclosed by (0.22, 0.16).

In the present invention, the chromaticity of the emission color of the red LED package is (0.66, 0.23), (0.423, 0.355), (0.5, 0.5) in CIE1931 chromaticity coordinates. ) and the chromaticity boundary line.

According to the present invention, in an LED lighting device using a plurality of light sources of different colors, it is possible to improve the accuracy of dimming and color adjustment control and prevent reading failures of barcodes and two-dimensional barcodes. be able to.

FIG. 2 is a configuration diagram of a lighting control/driving circuit according to the first embodiment; Explanatory drawing explaining the relationship between a high output/low output control signal and a drive output. A table for explaining the relationship between high-output/low-output control signals and drive output. 1 is an external perspective view of a lighting device according to Embodiment 1. FIG. FIG. 2 is a cross-sectional view of the fixture main body and the linear light source in the lighting device of Embodiment 1; 4 is a chromaticity diagram of an LED package used in the lighting device of Embodiment 1. FIG. Explanatory drawing which shows the temporal change of the relationship of three drive outputs.

<Embodiment 1>
<Lighting control/drive circuit>
FIG. 1 shows a configuration diagram of a lighting control/driving circuit in the lighting device according to the present embodiment. It has a tablet 100 as a setting terminal and a lighting device 300, and is capable of wirelessly transmitting a dimming signal.

A tablet 100, which is a setting terminal, includes a touch panel display 101, which is a display unit, and a transmitter 107 therein. The touch panel display 101 can display and set the setting chromaticity input section 102 and the total dimming rate input section 103, and the basic control signal 108 based on the input chromaticity and total dimming rate is output. It is transmitted by radio waves from the transmitter 107 .

The illumination device 300 includes a receiver 109, a control circuit 115, drive circuits 131, 132, and 133, and first, second, and third light source units 151, 152, and 153 that emit light in different colors.

The receiver 109 receives the basic control signal 108 , generates color-specific control signals 111 , 112 , and 113 for controlling the three light source units based on the basic control signal 108 , and sends them to the control circuit 115 . The color-specific control signals 111, 112, and 113 are, for example, PWM signals whose pulse width changes according to the signal value of 0 to 100%, but are not limited to this.

The control circuit 115 generates a high-output control signal 121H and a low-output control signal 121L, which are output control signals from the color-specific control signal 111, and a high-output control signal 122H and a low-output control signal 122L, which are output control signals from the color-specific control signal 112. , a high-output control signal 123H and a low-output control signal 123L, which are output control signals, are generated from the color-specific control signal 113 (details will be described later).

Based on the high output control signal 121H and the low output control signal 121L, the high output control signal 122H and the low output control signal 122L, and the high output control signal 123H and the low output control signal 123L, respectively, the drive circuits 131, 132, and 133 Generating drive outputs 141 , 142 , 143 .

The three-color light source units 151, 152, and 153 include, for example, circuits in which LEDs of the same color are connected in series and/or in parallel, and are driven by drive outputs 141, 142, and 143, respectively (a single LED may be used). ).

<High output/low output control signal and drive output>
The relationship between the high-output control signal 121H/low-output control signal 121L and the drive output 141 will be described with reference to FIG. 2, which is a schematic diagram of signal waveforms.

H in FIG. 2 shows the signal waveform of the high-output control signal 121H (or 122H, 123H), where the vertical axis is the voltage value (or current value) and the horizontal axis is time. L indicates the low output control signal 121L (or 122L, 123L), the vertical axis is the voltage value (or current value), and the horizontal axis is time. D indicates the drive output 141 output by the drive circuit 131 based on the high output control signal 121H and the low output control signal 121L, where the vertical axis is the current value (or voltage value) and the horizontal axis is time. The H pulse interval is, for example, approximately 42 μs (approximately 24 kHz cycle), and the L pulse interval is approximately 4.2 ms (approximately 240 Hz cycle).

The drive output D is expressed by the product of the signal value of the high output control signal H (the value of 0 to 100% transmitted as a signal, not the signal waveform) and the signal value of the low output control signal L, and the state of the drive output D is the value shown in FIG. 3 (table). The numbers here are percentages when the maximum D is taken as 100%, and D-MODE indicates whether the drive output D is an analog output (A) or a PWM output (P ), which is an example of a pulse output. ing. The boundary output, which is the boundary between A and P, was set to 6.25% in this example.

In FIG. 2, when the drive output D is 100%, 80%, 50%, and 6.25%, the current value of D changes as an analog value, and the waveform is constant. This change in output (current value) is realized by a change in the high-output control signal H. FIG. In the range of D from 100% to the boundary output of 6.25%, the L signal remains unchanged at 100%.

Looking at the cases where the driving output D is on the lower output side than the boundary output 6.25%, 5 %, 3.16%, and 1.25%, the analog output of the driving output D is constant and the driving output The pulse shape, which is the waveform of D, changes with the signal of the low power control signal L. FIG. In the range where the drive output D is lower than the boundary output, the H signal waveform is the same and does not change.

In this manner, using the high output control signal H and the low output control signal L, which are output control signals, the current value of the drive output D is controlled by the high output control signal H on the high output side where the drive output D is equal to or higher than the boundary output. On the lower output side than the boundary output, the drive output D can be controlled by controlling the pulse width/interval of the drive output D as a PWM output with the low output control signal L. FIG. Any output control signal may be used as long as the drive output can be analog output controlled on the high output side of the boundary output or higher, and the pulse width/interval control can be performed on the low output side.

As a result, on the lower output side than the boundary output, the accuracy of dimming control is improved compared to the case of analog control only, and barcodes and 2D barcodes are displayed in the entire dimming range (0% to 100%). Illumination that does not interfere with reading can be performed.

In this lighting control device, the waveform of the drive output D in FIG. , the amplitude of the light output waveform of the LED can be reduced.

<Lighting device>
A lighting device 300 according to the present embodiment is a fixture main body/linear light source separation type lighting device. As shown in FIG. 4, which is an external perspective view, this has a fixture body 310 directly attached to the ceiling and a linear light source 320 attached to the fixture body 310 . Since the fixture main body 310 and the linear light source 320 are separable, the linear light source 320 can hide screws or hanging bolts for attaching the fixture main body 310 to the ceiling. The width of the illumination device is 2 cm as an example, and the length is 120 cm as an example.

A cross-sectional view of the fixture body 310 and the linear light source 320 is shown in FIG. The device main body 310 has a box shape with an open bottom surface, and includes a spring receiver 311 and a connector 312 .

The linear light source 320 includes a mounting portion 321 , a substrate 322 , an LED package 323 , a diffusion cover 324 , a power source 325 , a control portion 326 , a mounting spring 327 and a connector 328 . The mounting spring 327 is attached to the spring receiver 311 of the instrument body 310 , the connector 328 is connected to the connector 312 of the instrument body 310 , and commercial power is supplied to the power supply 325 . Note that an "LED" may be called an "LED package" to distinguish it from an LED chip, which will be described later.

The power supply 325 converts commercial alternating current power into direct current and has three channels of drive output to operate three types of LED packages, and each drive output can be controlled by an external control signal. In this embodiment, the control signal is wirelessly transmitted and received by the controller 326 , which sends the control signal to the power supply 325 to control the power supply 325 .

The control unit 326 includes the receiver 109, and the power supply 325 includes the control circuit 115 and the drive circuits 131, 132, and 133. For example, the drive circuits 131, 132, and 133 may be provided on the substrate 322 or another substrate. .

The LED packages 323 on the substrate 322 constitute the light sources 151 , 152 and 153 . That is, a three-color LED package is used as the LED package.

<LED chromaticity>
As the LED packages 323 used for the light source units 151, 152, and 153, a bluish white LED "Bw", a red LED "R", and a yellowish white LED "Yw" are used, respectively. FIG. 6 shows chromaticity coordinates for explaining the chromaticity of these LEDs. For reference, a dotted line shows a line connecting the chromaticities of black body radiation at each color temperature.

Bw, which is a blue-white LED, is (0.336, 0.24), (0.352, 0.44), (0.15, 0.2), (0. 2, 0.1), an example of which is (0.23, 0.26).

The red LED R is (0.66, 0.23), (0.423, 0.355), (0.5, 0.5) and the chromaticity boundary line E The light is emitted with a chromaticity in the range enclosed by (0.60.0.38) as an example. Note that it is not the same as the general definition of red.

Yw, which is a yellow-white LED, is (0.423, 0.355), (0.342, 0.312), (0.352, 0.44), (0.37 , 0.63) and chromaticity in the range enclosed by the chromaticity boundary line E, for example (0.44, 0.47).

Within the chromaticity range of Yw, a range in which d _uv is positive from a line connecting the chromaticity of black body radiation at each color temperature is preferable, and a range in which d _uv is plus 0.03 to 0 is particularly preferable.

Among the chromaticity ranges of Bw and R, a range of _+0.03 to -0.03 in duv from the line connecting the chromaticities of blackbody radiation at each color temperature is particularly preferable.

It should be noted that the chromaticity coordinates (x, y) in CIE1931 can also be displayed in chromaticity coordinates (u', v') in CIE1976, and both u'=4x/(-2x+12y+3), v'=9y/ They can be mutually converted by a conversion formula of (-2x+12y+3). It may be displayed in another chromaticity coordinate system.

<Driving of this lighting device by analog pulse control>
The operation of this illumination device is considered from the viewpoint of achieving good bar code reading under illumination using the above three colors of red (R), yellowish white (Yw), and bluish white (Bw). When only one of R, Yw, and Bw lights up at 100%, it becomes such colored special lighting. In practice, a pleasant lighting can be achieved by mixing the colors. For example, (R, Yw, Bw) = (55%, 55%, 10%) for a color temperature of 2800K, which is the color gamut normally used, and (R, Yw, Bw) = (17%) for a color temperature of 5000K. , 40%, 66%). In this case, if the boundary output is set to 13%, the number of colors for which the pulse operation is performed is at most one, and the illumination brightness of the other colors that are analog-lit becomes dominant. Therefore, there is no adverse effect on bar code reading.

On the other hand, for example, if the overall brightness is 1/5 of the above, all three colors will be pulsed (see the next section for countermeasures when two or all three colors are pulsed). Barcodes are unlikely to be read under subdued lighting, and if barcode reading is desired, the overall illumination may simply be increased.

As described above, the illumination using the light sources of three colors is less susceptible to barcode read failure due to the pulse operation than the illumination using the light sources of one color. Therefore, even if the boundary output is set low in the case of illumination using a light source of one color, in the case of illumination using light sources of three colors, the boundary output may be set to 20% or more, 30% or more, or 50%. You can set it higher.

<Timing of drive output for three colors>
In this embodiment, the low output control signals L (121L, 122L, 123L) for controlling the low output side of the driving outputs D (141, 142, 143) are not synchronized but made independent. Therefore, each drive output on the lower output side than the boundary output also becomes a pulse waveform with independent timing without synchronism.

FIG. 7 shows temporal changes in the relationship between the three drive outputs 141, 142 and 143 (horizontal axis is time). Since the drive outputs are not synchronized, the pulses may always be aligned (S in FIG. 7), but the PWM signal frequency is slightly off, so after a while the pulses of the three colors will not be aligned (Fig. AS of 7). Even if barcode reading is hindered in the state of S in FIG. 7, it will be in the state of AS in FIG. 7 after a while. did.

The drive outputs 141, 142, and 143 can be synchronized in a state in which the pulses do not overlap in terms of time (AS in FIG. 7), and even in that case, barcode reading is less likely to be hindered.

<Variation>
Although the PWM signal or PWM output is exemplified as the pulse signal or pulse output in the embodiments, other pulse shapes such as a PFM (Pulse Frequency Modulation) signal or PFM output may be used.

In the embodiment, an example in which one setting terminal controls one lighting device is shown, but one setting terminal may control a plurality of lighting devices, which is more common.

Although a tablet is used as the setting terminal in the embodiment, a smartphone, a computer, or the like may be used.

In the embodiment, the illumination device is provided with three-color light sources, but the illumination device may be provided with monochromatic or two-color light sources. Further, when three colors are used, in addition to Bw (bluish white), Yw (yellowish white), and R (red) described in the embodiment, for example, B (blue), G (green), and R (red) light sources are used. may be used.

Also, light sources of four or more colors may be used. In addition to Bw (bluish-white), Yw (yellowish-white), and R (red), at least one color of, for example, cyan, magenta, or green may be added, and B (blue) , G (green), and R (red), for example, at least one of white, cyan, magenta, and yellow may be added.

In the embodiment, the setting signal of the lighting device is wirelessly transmitted from the external setting terminal, but the setting signal may be transmitted by wire or by being superimposed on the power supply line. When transmitting, the wireless transmission method is preferably IEEE802.15.1 (Bluetooth (registered trademark)) or IEEE802.15.4 (ZigBee (registered trademark) ). (Digital Addressable Lighting Interface), DXM512, and other transmission formats may be used.

In the embodiments, a linear lighting device is used as the lighting device, but a lighting device with a square or circular light emitting part may be used, and any of various types of lighting devices such as downlights, spotlights, and LED bulbs may be used. There may be.

It should be noted that the above-described embodiment disclosed this time is an example in all respects and does not serve as a basis for restrictive interpretation. Therefore, the technical scope of the present invention is not to be interpreted only by the above-described embodiments, but is defined based on the claims. In addition, all changes within the meaning and range of equivalents to the scope of claims are included.

100 Tablet 101 Touch panel display 102 Setting chromaticity input unit 103 Total dimming ratio input unit 107 Transmitter 108 Basic control signal 109 Receivers 111, 112, 113 Color-specific control signal 115 Control circuit 121H, 122H, 123H High output control signal 121L , 122L, 123L Low output control signals 131, 132, 133 Drive circuits 141, 142, 143 Drive outputs 151, 152, 153 LED light source section 300 Lighting device 310 Fixture main body 312 Connector 320 Linear light source 321 Mounting section 322 Substrate 323 LED package 324 Diffusion cover 325 Power supply 326 Control unit 327 Mounting spring 328 Connector

Claims (10)

A lighting device capable of controlling the light output of a light source of multiple colors,
a control circuit for generating a high-output control signal and a low-output control signal from an externally transmitted color-specific control signal for each color;
a drive circuit that generates a drive output based on the high output control signal and the low output control signal;
The high-output control signal is a PWM signal or a PFM signal that controls the analog value of the driving output ,
The high-output control signal changes according to a change in the color-specific control signal when the color-specific control signal controls the output side above the boundary output, and the color-specific control signal changes the output below the boundary output. does not change according to the change of the color-specific control signal ,
The low output control signal is a signal that controls the pulse shape of the drive output ,
The low output control signal does not change in accordance with a change in the color-specific control signal when the color-specific control signal controls the output side above the boundary output, and the color-specific control signal is below the boundary output. In the case of controlling the output of, it changes according to the change of the color-specific control signal,
The driving outputs generated for each of the colors are respectively output to the light sources of the respective colors;
lighting device. 2. The lighting device according to claim 1, wherein the drive output is an analog output on the high output side of the boundary output or more, and is a pulse output on the low output side of the boundary output. 3. The lighting device according to claim 1, wherein said low output control signal is a PWM signal or a PFM signal on a lower output side than said boundary output. 4. The lighting device according to claim 3 , wherein said plurality of drive outputs are not synchronized with each other on the output side lower than said boundary output. A lighting device capable of controlling the light output of a light source of multiple colors,
a control circuit for generating an output control signal from the color-specific control signal transmitted from the outside for each color;
A drive circuit that generates a drive output based on the output control signal,
The output control signal is a signal that controls the analog value of the drive output on the high output side above the boundary output and controls the pulse shape of the drive output on the lower output side than the boundary output,
the drive output is an analog output on the high output side of the boundary output or more, and is a pulse output on the low output side of the boundary output;
wherein said plurality of drive outputs are not synchronized with each other in the case of said pulsed outputs;
The lighting device, wherein the drive output generated for each color is output to the light source of each color. 6. A lighting device according to any one of the preceding claims, wherein said lighting device comprises light sources of three or more colors. 7. The lighting device according to claim 6 , wherein said light sources of three or more colors include red LEDs, yellowish white LEDs, and bluish white LEDs. The chromaticity of the emission color of the yellow-white LED package is (0.423, 0.355), (0.34, 0.28), (0.352, 0.44), 8. The illumination device of claim 7 , wherein the chromaticity is in the range enclosed by (0.37, 0.63) and the chromaticity boundary line. The chromaticity of the emission color of the blue-white LED package is (0.34, 0.28), (0.352, 0.44), (0.18, 0.24), ( 8. A lighting device according to claim 7 , within the range of chromaticities bounded by 0.22, 0.16). The chromaticity of the emitted color of the red LED package is (0.66, 0.23), (0.423, 0.355), and (0.5, 0.5) in CIE1931 chromaticity coordinates. 8. The lighting device of claim 7 , wherein the chromaticity is a bounded range.

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