JP2007250350A - Continuously variable color temperature lighting system and continuously variable color temperature lighting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a continuously variable color temperature lighting system and a continuously variable color temperature lighting method, capable of continuously changing color temperature of mixing color mixed with changing luminance rates of LEDs of different light-emitting colors. <P>SOLUTION: The continuously variable color temperature lighting system includes three driving parts 21, 22, 23 driving/irradiating LEDs 31, 32, 33 of each light-emitting color, a control part 12 for controlling each driving part above to emit light with a specified illuminance ratio, and a color temperature adjustment input part 11 for outputting specified signals in accordance with the specified color temperature to the control part. The control part calculates the illuminance ratio of each light-emitting color corresponding to the specified color temperature, referring table data 12a of the illuminance ratio of each light-emitting color registered beforehand, and based on the above specified signals, then each driving part is controlled based on the calculated result. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a continuously variable color temperature illumination device and a continuously variable color temperature illumination method using LEDs as light sources.

Conventionally, when white light is obtained by an LED, a blue or blue-violet LED and a phosphor that converts the wavelength of light from the LED are combined, and the emission color of the LED and the emission color of the phosphor are in a complementary color relationship. Thus, a white LED is known in which a white color is obtained by mixing these lights.
However, in any of the white LEDs having such a configuration, since the user cannot adjust the amount of the phosphor, it is impossible to change the correlated color temperature, for example.
Therefore, when it is desired to change the color temperature, it has been necessary to replace it with an illumination lamp such as an LED having a different color temperature.

On the other hand, in addition to the three primary colors such as red, green and blue LEDs, other colors such as orange, yellow and turquoise LEDs are used to adjust the light flux ratio and mix the colors. An LED having a high average color rendering evaluation coefficient Ra and a desired correlated color temperature is also known.
However, in this case, it is possible to achieve a high average color evaluation number by adjusting the luminous flux ratio of the six types of light from each LED, but LEDs that emit six types of light are necessary. The control circuit for adjusting the luminous flux ratio of the LED becomes complicated, and in order to obtain good color mixing, the arrangement and color mixing method of the LEDs become difficult, which is not practical.

A white LED is also known in which white light is obtained by combining a blue LED, a phosphor filter that converts the blue light of the blue LED into green and a red LED.
In the white LED having such a configuration, the correlated color temperature can be adjusted by adjusting the luminous flux ratio between the blue-green light by the blue LED and the phosphor filter and the red light of the red LED.
However, since the locus of chromaticity of the light source color is a straight line, it is difficult to obtain chromaticity according to the color temperature locus of the complete radiator or the daylight locus in the CIE.

On the other hand, according to Patent Document 1, a color temperature variable LED light source including a white LED, a green LED, and a red LED and a diffusion unit that mixes white light, green light, and red light from each of these LEDs. A module is disclosed.
According to the color temperature variable LED light source module having such a configuration, the color temperature of the mixed color light can be made variable by appropriately adjusting the luminous flux ratio of the light from each LED and mixing the colors by the diffusion unit.
JP 2002-270899 A

  However, in the color temperature variable LED light source module according to Patent Document 1, it is possible to change the color temperature, but the obtained mixed color is limited to daylight color, day white, white, warm white, and light bulb color. Thus, the user cannot freely and easily change the color temperature continuously.

  In view of the above, the present invention provides a continuously variable color temperature illumination device and a color temperature that can continuously change the color temperature of mixed color light by changing the luminance ratio of LEDs having different emission colors. It aims to provide a continuously variable illumination method.

According to the first configuration of the present invention, at least one of the first LED, the second LED, the third LED, and the LEDs of the respective emission colors, which are different from each other in emission color, are driven. A first drive unit that emits light, a second drive unit, and a third drive unit, a control unit that controls each of the drive units to emit light at a specified luminance ratio, and an input operation by an operator A color temperature adjustment input unit that outputs a designated color temperature or a designation signal corresponding to the color to the control unit, and the control unit determines the luminance ratio of each light emission color registered in advance. Referring to the data table, the luminance ratio of each emission color corresponding to the specified color temperature or color is calculated based on the specified signal, and each drive unit is calculated based on the calculated luminance ratio of each emission color. Characterized by controlling,
Furthermore, in the color temperature continuously variable illumination device, the data table is a data table of luminance ratios of light emission colors for realizing a plurality of color temperatures or colors, and the control unit receives the designation signal. Based on the data table, when the color temperature or color between the points is designated, linear interpolation is performed between these points to determine the emission color corresponding to the designated color temperature or color. The luminance ratio is calculated.

In the first aspect, when the user inputs a desired color temperature or color at the color temperature adjustment input unit, a designation signal corresponding to the color temperature or color designated from the color temperature adjustment input unit is transmitted to the control unit. Is output.
Then, the control unit calculates the luminance ratio of each emission color corresponding to the specified color temperature or color based on this designation signal, and calculates the luminance of each emission color as a calculation result. Based on the ratio, the drive unit for each emission color LED is controlled.
As a result, the LEDs of each emission color are driven by the drive unit, and the LEDs of each emission color emit light at a predetermined luminance ratio. Accordingly, the light emitted from the LEDs of the respective emission colors is mixed with each other to obtain mixed color light having a desired color temperature or color.
In addition, when a color temperature or color between a plurality of points is selected, the luminance ratio of each emission color can be calculated approximately by a linear interpolation method.
In addition, since the data table only needs to have the luminance ratio of each emission color in the color temperature or chromaticity coordinates for a plurality of points, the number of data can be reduced, the data table can be easily created, When the data table is stored in the storage device, the occupied memory capacity is small.

  In this case, the color temperature or color of the mixed color light can be continuously changed by an input operation to the color temperature adjustment input unit by the user. Therefore, it is possible to change the color temperature without changing to an illuminating lamp having a different color temperature or to switch the color temperature with a switch as in the past, and to continuously change the color temperature of the mixed color light by the input operation. Thus, the desired color temperature or color mixed light can be easily adjusted.

The color temperature continuously variable illumination device according to the second aspect of the present invention is the color temperature continuously variable illumination device according to the first aspect, wherein the data table is for each emission color for realizing a color on chromaticity coordinates. It is a data table of luminance ratios.
In the second aspect, a color mixture light of a desired color can be obtained by selecting a luminance ratio based on a data table using chromaticity coordinates.

The continuously variable color temperature illumination device according to the third aspect of the present invention is the color temperature continuously variable illumination device according to the first aspect, in which the data table has each light emission for realizing a color temperature on a black body radiation locus. It is a data table of color luminance ratios.
In the third aspect, color mixture light having a desired color temperature can be obtained by selecting a luminance ratio based on a data table using a black body radiation locus.

According to a fourth aspect of the present invention, there is provided the continuously variable color temperature illumination device according to any one of the first to third aspects, wherein the data table is stored in a storage device connected to the control unit. It is stored.
In the fourth aspect, since the data table is created in advance and stored in the storage device, the control unit can easily and quickly refer to the data table stored in the storage device to obtain the luminance ratio. Can be calculated more quickly.

  In the color temperature continuously variable illumination device according to any one of the first to fifth aspects, if the emission color is red, green, and blue, and the data table is an RGB luminance ratio data table, By making the emission colors red, green and blue, which are the three primary colors of light, it is possible to use commonly used red LED, green LED and blue LED, and the component cost can be reduced. Become.

A color temperature continuously variable illumination device according to a fifth aspect of the present invention is the color temperature continuously variable illumination device according to any one of the third and fourth aspects, wherein the color temperature adjustment input unit is configured to provide a logarithm of the color temperature. The linear color temperature signal is output, and the data table gives a luminance ratio of each emission color to the linear color temperature signal or a linear value obtained by performing a predetermined operation on the color temperature signal. It is characterized by that.

In this fifth aspect, the human sense of color temperature is sensitive at low color temperature, but insensitive to high color temperature, and by taking the logarithm of color temperature, the sense of color is taken. It is possible to present a change in color temperature that matches the specific characteristics.
Therefore, the user can set an appropriate color temperature change without a sense of incongruity at the color temperature adjustment input unit.

In another aspect, in the continuously variable color temperature lighting device according to any one of the first to fifth aspects, the data table includes two of the three emission colors for the designated color temperature or color. It is also possible to provide a luminance ratio of two emission colors.
In this aspect, the data table gives only the luminance ratio of the two emission colors, but the remaining emission colors can be easily calculated from the luminance ratio of the other two emission colors.
Therefore, since the number of data in the data table can be reduced, the data table can be easily created, and when the data table is stored in the storage device, the occupied memory capacity can be reduced.

The color temperature continuously variable illumination device according to a sixth aspect of the present invention is the color temperature continuously variable illumination device according to any one of the first to eighth aspects, wherein the data table is replaced with a luminance ratio of each color. Is a data table that gives a numerical value corresponding to the luminance ratio, the control unit controls each drive unit based on the corresponding numerical value,
The numerical value corresponding to the luminance ratio is a calculated value based on an index or coefficient that can adjust the luminance of the LED, such as the luminous flux ratio of each color, the LED driving duty ratio, the LED driving current or driving voltage, and the LED light output. Features.

In the sixth aspect, the control unit controls the driving unit for the LEDs of the respective emission colors based on the numerical values given by the data table instead of the luminance ratios, so that each emission color can be set at the desired luminance ratio. The LED can emit light.
Further, instead of the luminance ratio, the table uses a calculation value based on the index or coefficient, that is, a calculation value during the calculation when the control unit calculates a control signal of each driving unit based on the luminance ratio, or a duty ratio. By providing drive control values such as drive current, drive voltage, and light output, it is possible to drive and control the LEDs of each emission color at a desired luminance ratio.

In addition, according to the second configuration (seventh aspect) of the present invention, the object is to provide a first stage for generating a designation signal corresponding to a designated color temperature or color, and each light emission registered in advance. A second stage for calculating the luminance ratio of each emission color corresponding to the specified color temperature or color based on the specified signal with reference to the color luminance ratio data table, and each calculated emission color A third control unit that controls each drive unit based on the luminance ratio of each of the first and second LEDs and the third LED having different emission colors from each other at a predetermined luminance ratio. And including stages,
The data table is a data table of luminance ratios of light emission colors for realizing color temperatures or colors at a plurality of points, and the data table is referred to based on the designation signal in the second stage. When the color temperature or color between the points is specified, the luminance ratio of each emission color corresponding to the specified color temperature or color is calculated between these points by linear interpolation. This is achieved by the color temperature continuously variable illumination method.

In the seventh aspect, in the first stage, the user designates a desired color temperature or color to generate a designation signal corresponding to the designated color temperature or color, and in the second stage. Based on this designation signal, the luminance ratio of each emission color corresponding to the designated color temperature or color is calculated with reference to the data table, and in the third stage, the calculated emission color of each emission color is calculated. Based on the luminance ratio, the LED of each emission color is driven and controlled.
In this case, the color temperature or color of the mixed color light can continuously change in accordance with the user's color temperature or color designation in the first stage. Therefore, it is possible to change the color temperature without changing to an illuminating lamp having a different color temperature or to switch the color temperature with a switch as in the prior art. The color temperature or the mixed color light of the color can be easily adjusted.
As a result, the LEDs of the respective emission colors emit light at a predetermined luminance ratio, and the light emitted from the LEDs of the respective emission colors is mixed with each other to obtain mixed color light having a desired color temperature or color. become.

  In addition, when a color temperature or color between a plurality of points is selected, the luminance ratio of each emission color can be calculated approximately by a linear interpolation method. Since the data table only needs to have the luminance ratio of each luminescent color in the color temperature or chromaticity coordinates for a plurality of points, the number of data can be reduced, and the data table can be easily created.

  Furthermore, as another aspect, in the color temperature continuously variable illumination method according to the seventh aspect, if the data table is a data table of a luminance ratio of each emission color for realizing a color on chromaticity coordinates, By selecting a luminance ratio based on a data table using chromaticity coordinates, mixed color light of a desired color can be obtained.

  Furthermore, as another aspect, in the color temperature continuously variable illumination method according to the seventh aspect of the present invention, the data table is a data table of the luminance ratio of each luminescent color for realizing the color temperature on the black body radiation locus. Then, based on the data table using the black body radiation locus, the color mixture light having a desired color temperature can be obtained by selecting the luminance ratio.

  In the color temperature continuously variable illumination method according to any one of the above aspects, if the emission colors are red, green, and blue and the data table is an RGB luminance ratio data table, the emission color is the three primary colors of light. By using red, green, and blue, it is possible to use commonly used red LED, green LED, and blue LED, and the component cost can be reduced.

  In the color temperature continuously variable illumination method using the luminance ratio data table of each emission color for realizing the color temperature on the black body radiation locus, in the first stage, linear with respect to the logarithm of the color temperature. And the data table gives a luminance ratio of each emission color to the linear designation signal or a linear value obtained by performing a predetermined operation on the designation signal.

In this case, the human sense of color temperature is sensitive at low color temperature, but is insensitive at high color temperature. A change in color temperature suitable for the characteristics can be presented.
Therefore, the user can set an appropriate color temperature change without a sense of incongruity at the color temperature adjustment input unit.

Furthermore, in the color temperature continuously variable illumination method according to any one of the above aspects, the data table is configured to give a luminance ratio of two emission colors among the three emission colors with respect to a specified color temperature or color. It can also be characterized by being.
In this case, the data table gives only the luminance ratio of the two emission colors, but the remaining emission colors can be easily calculated from the luminance ratio of the other two emission colors.
Therefore, since the number of data in the data table can be reduced, the data table can be easily created, and when the data table is stored in the storage device, the occupied memory capacity can be reduced.

  In the color temperature continuously variable illumination method according to the eighth aspect of the present invention, the data table is a data table for giving numerical values corresponding to the luminance ratios instead of the luminance ratios of the respective colors, Then, the LED of each light emitting color is driven and controlled based on the corresponding numerical value, and the numerical value indicates the luminance of the LED such as the luminous flux ratio of each color, the LED driving duty ratio, the LED driving current or driving voltage, and the LED light output. It is characterized by being a calculated value by an index or coefficient that can be adjusted.

In the eighth aspect, the LEDs of the respective emission colors can be caused to emit light at the desired luminance ratio by driving and controlling the LEDs of the respective emission colors based on the numerical value given by the data table instead of the luminance ratio.
Instead of the luminance ratio, the table calculates values based on the above-mentioned index or coefficient, that is, calculated values during the calculation of the control parameters for driving the LEDs of the respective emission colors based on the luminance ratio, and the duty ratio By providing drive control values such as drive current, drive voltage, and light output, it is possible to drive and control the LEDs of each emission color at a desired luminance ratio.

As described above, according to the present invention, the designation signal corresponding to the designated color temperature or color is generated, and the designated color temperature or color is obtained by referring to the data table based on the designation signal. By calculating the luminance ratio of each corresponding emission color, the LED of each emission color is driven and controlled based on the calculated luminance ratio of each emission color.
As a result, the LEDs of the respective emission colors emit light at a predetermined luminance ratio, and the light emitted from the LEDs of the respective emission colors is mixed with each other to obtain mixed color light having a desired color temperature or color. become.
Since the specified color temperature or the luminance ratio corresponding to the color is calculated using the linear interpolation method with reference to the data table, the calculation can be performed easily and quickly.
Therefore, according to the present invention, it is possible to continuously change the color temperature of the mixed color light by changing the luminance ratio of the LEDs having different emission colors, and it is possible to continuously change the color temperature continuously variable illumination device. A color temperature continuously variable illumination method could be provided.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to FIGS.
The embodiments described below are preferable specific examples of the present invention, and thus various technically preferable limitations are given. However, the scope of the present invention particularly limits the present invention in the following description. As long as there is no description of the effect, it is not restricted to these aspects.

FIG. 1 shows a configuration of an embodiment of a continuously variable color temperature illumination device according to the present invention.
In FIG. 1, a color temperature continuous variable illumination device 10 includes a color temperature adjustment input unit 11, a control unit 12, a storage unit 13, and three driving units for each emission color (in this case, red, green, and blue). 21, 22, and 23, and light emitting units 30 including LEDs of respective emission colors, that is, red LEDs, green LEDs, and blue LEDs.

The color temperature adjustment input unit 11 can input a numerical value that can be continuously changed by, for example, a volume.
The color temperature adjustment input unit 11 outputs the designated instruction value as the designation signal x to the control unit 12.
Further, the color temperature adjustment input unit 11 is provided with a scale (not shown) that serves as a guideline for setting the color temperature, adjacent to the volume. The color temperature can be set.
Here, the scale is displayed as a logarithmic scale with respect to the color temperature from the viewpoint of operability, as will be described later.

Based on a designation signal from the color temperature adjustment input unit 11, the control unit 12 refers to a data table 12a described later and calculates a luminance ratio for each light emission color.
Here, the data table 12a is configured, for example, as shown in FIG. 2, and the color temperature adjustment input unit 11 for each of the sections A to L obtained by logarithmically dividing the color temperature sequentially from the lower one. It is created in advance so as to give the section maximum value x of the designation signal x corresponding to the scale and the linear approximation constants a r, br and ag, b g of the red LED in the section.

Then, the control unit 12 refers to such a data table 12a, and determines the luminance ratio yr of the red LED, the luminance ratio yg of the green LED, and the luminance ratio yb of the blue LED based on the designation signal x as follows. Formula (Equation 1) yr = ar * x + br
yg = ag * x + bg
yb = 1-yr -yg
Is calculated by a so-called linear interpolation method.
Thereafter, the control unit 12 controls the driving units 21, 22, and 23 based on the luminance ratios yr, yg, and yb, and the dimming control of the red LED, the green LED, and the blue LED of the light emitting unit 30. To do.

In this case, assuming that the target luminance of the mixed color light is Y, the target luminances Yr, Yg and Yb of the LEDs of the respective emission colors are respectively expressed by the following equations:
(Equation 2) Yr = Y × yr
Yg = Y × yg
Yb = Y × yb
Is required.
Accordingly, the control unit 12 determines each dimming control amount, for example, a duty ratio in PWM, so that the LEDs of the respective emission colors emit light with these target luminances Yr, Yg and Yb, and the drive unit 21, 22 and 23 are driven and controlled.

  The storage unit 13 is an auxiliary storage device such as a semiconductor memory or a hard disk drive, and is connected to the control unit 12. The data table 12 a described above is stored in a readable / writable manner from the control unit 12.

  The driving units 21, 22, and 23 drive the red LED, the green LED, and the blue LED of the light emitting unit 30, respectively, based on the control signal from the control unit 12, that is, the dimming control amount described above.

The light emitting unit 30 includes a red LED 31, a green LED 32, and a blue LED 33 as LEDs of each emission color, and a lens, a reflector, and a diffusion so as to mix light emitted from the LEDs 31, 32, and 33 with each other. An optical system 34 composed of a plate or the like is provided.
As a result, the light emitted from the LEDs 31, 32, 33 is mixed with each other by the optical system 34, and is emitted as a substantially uniform color, that is, mixed color light having a specified color temperature.
Each LED 31, 32, 33 is used in an arbitrary number of one or more.

Here, a method of creating the data table 12a described above will be described.
First, as shown in FIG. 3, the luminance ratios at various color temperatures are adjusted by adjusting the light emission luminance of each of the LEDs 31, 32, and 33 so that a predetermined color temperature is obtained on the black body radiation locus. Measure by experiment.
In FIG. 3, each point shown on the blackbody radiation locus is a measurement point.

Subsequently, the luminance ratio of each emission color at each measurement point is calculated, and a graph of the luminance ratio of each emission color with respect to the color temperature is obtained as shown in FIG.
Here, the graph of FIG. 4 is shown as a semi-logarithmic graph in which the color temperature is shown on a logarithmic scale.
This is because an appropriate color temperature change without a sense of incongruity is presented in consideration of human perception of color temperature (sensitive at low color temperature, insensitive at high color temperature).

The graph of FIG. 5 is created by taking the logarithm of the color temperature in the graph of FIG. 4 and expressing the color temperature range from 2000K to 80000K by the color temperature adjustment scale (the aforementioned designation signal) x. .
The relationship between the color temperature and the color temperature adjustment scale x is as shown in the graph of FIG. 6, and the color temperature adjustment scale x is linear with respect to the logarithm of the color temperature.

Next, in order to approximate the curve of each luminance ratio in the graph of FIG. 4 with a broken line, the graph is divided into several sections (in the case of illustration, 12 sections A to L), and each plot is plotted for each section A to L. By expressing the interval with a straight line, the graph shown in FIG. 7 is created.
For each section A to L, the a and b values in the approximate line y = a · x + b are tabulated together with the maximum value of x in each section, thereby completing the data table 12a described above.
Here, regarding the blue light, if the luminance ratio of the red light and the green light is known, it is uniquely determined by the above-described formula, and thus is not included in the data table 12a.
The data table 12a obtained in this way is stored in the storage unit 13 described above so as to be readable and writable.

The continuously variable color temperature illumination device 10 according to the embodiment of the present invention is configured as described above and operates as follows.
First, in the flowchart of FIG. 8, in step S <b> 1, the user operates the volume of the color temperature adjustment input unit 11 to adjust the scale corresponding to a desired color temperature.
Thereby, in step S2, the color temperature adjustment input unit 11 outputs the instruction value designated by the volume to the control unit 12 as the designation signal x.

In response, the control unit 12 reads the data table 12a from the storage unit 13 in step S3, and in step S4, based on the designation signal x from the color temperature adjustment input unit 11, the data. With reference to the table 12a, the luminance ratio of each emission color is calculated by the linear interpolation method.
Subsequently, in step S5, the control unit 12 calculates a dimming control amount for each of the drive units 21, 22, and 23, for example, a duty ratio of PWM, from the calculated luminance ratio of each emission color. In step S 6, a control signal is sent to each of the drive units 21, 22, and 23 based on the dimming control amount.

Thereby, in step S7, each drive part 21,22,23 drives red LED31, green LED32, and blue LED33 of the corresponding light emission part 30 based on these control signals, respectively.
Then, in step S8, the LEDs of the respective emission colors, that is, the red LED 31, the green LED 32, and the blue LED 33 emit light at a predetermined luminance ratio and are mixed with each other by the optical system 34, thereby mixing the colors with the specified color temperature. Light is irradiated.
Thus, mixed color light having the designated color temperature is obtained.

  In addition, when the user wants to change the color temperature of the actually emitted mixed color light, the user operates the volume of the color temperature adjustment input unit 11 to set the scale corresponding to the desired color temperature, or actually The volume may be operated until the desired mixed color light is obtained while visually recognizing the color of the mixed color light emitted from the light emitting unit 30.

  In this way, when the user operates the volume of the color temperature adjustment input unit 11, the color temperature of the mixed color light of the light emitted from the LEDs 31, 32, 33 emitted from the light emitting unit 30 is continuously set. Can be changed.

In the embodiment described above, the red LED 31, the green LED 32, and the blue LED 33 are used as LEDs having different emission colors. However, the present invention is not limited to this, and it is obvious that a combination of LEDs of other emission colors may be used. .
In this case, the data table 12a may be created for the luminance ratios corresponding to these emission colors.

Further, in the above-described embodiment, the data table 12a has been described with respect to continuous variation of the color temperature that traces on the black body radiation locus, but not limited to this, the color temperature that traces on the chromaticity coordinates. It is apparent that the present invention can be applied to the case of continuously variable.
In this case, when the data table 12a is created, the data table 12a can be created in the same manner by obtaining a measurement value for the luminance ratio on the chromaticity coordinates.

  Furthermore, in the above-described embodiment, the data table 12a is configured to give the luminance ratio of each emission color to the color temperature. However, the present invention is not limited to this, and the data table 12a has a predetermined luminance ratio. It is obvious that a control signal for driving and controlling the LEDs 31, 32, 33, for example, a dimming control amount such as a PWM duty ratio, a driving voltage, a driving current, an optical output, or a luminous flux ratio may be given.

Thus, according to the present invention, the color temperature continuously variable illumination device capable of continuously changing the color temperature of the mixed color light by changing the luminance ratio of the LEDs having different emission colors, and A color temperature continuously variable illumination method can be provided.
The color temperature continuously variable illumination device and the color temperature continuously variable illumination method according to the present invention can be effectively used as various LED illumination luminances.

It is a block diagram which shows the structure of one Embodiment of the color temperature continuous variable illuminating device by this invention. It is a figure which shows an example of the data table used with the color temperature continuous variable illuminating device of FIG. It is a graph which shows the color temperature measurement result on the black body radiation locus for the data table preparation of FIG. It is a graph which shows the relationship between the color temperature by the measurement result of FIG. 3, and the luminance ratio of each luminescent color. It is a graph which shows the relationship between the color temperature in the graph of FIG.3 and FIG.4, and a color temperature adjustment scale. It is a graph which shows the relationship between the color temperature adjustment scale by the measurement result of FIG. 3, and the luminance ratio of each luminescent color. 6 is a graph obtained by approximating the graph of FIG. 5 with a broken line. It is a flowchart which shows operation | movement of the color temperature continuous variable illumination apparatus of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Color temperature continuous variable illumination apparatus 11 Color temperature adjustment input part 12 Control part 12a Data table 13 Memory | storage part 21,22,23 Drive part 30 Light emission part 31,32,33 LED
34 Optical system

Claims (8)

At least one first LED, second LED, and third LED, each having a different emission color, and
A first drive unit, a second drive unit, and a third drive unit for driving and emitting each LED of each emission color; and
A control unit that controls each of the driving units to emit light at a specified luminance ratio;
A color temperature adjustment input unit that outputs a designated color temperature or a designation signal corresponding to a color to the control unit in response to an input operation by the operator;
Contains
The control unit calculates a luminance ratio of each emission color corresponding to the specified color temperature or color based on the designation signal with reference to the data table of the luminance ratio of each emission color registered in advance. Control each drive unit based on the calculated luminance ratio of each emission color,
The data table is a data table of luminance ratios of the respective emission colors for realizing a plurality of color temperatures or colors, and the control unit refers to the data table based on the designation signal, When the color temperature or color between the points is specified, the luminance ratio of each emission color corresponding to the specified color temperature or color is calculated by linear interpolation between these points.
A color temperature continuously variable illumination device characterized by that.   The color temperature continuously variable illumination device according to claim 1, wherein the data table is a data table of a luminance ratio of each emission color for realizing a color on chromaticity coordinates.   The color temperature continuously variable illumination device according to claim 1, wherein the data table is a data table of a luminance ratio of each emission color for realizing a color temperature on a black body radiation locus.   The color temperature continuously variable illumination device according to any one of claims 1 to 3, wherein the data table is stored in a storage device connected to a control unit.   The color temperature adjustment input unit is configured to output a linear color temperature signal with respect to the logarithm of the color temperature, and the data table performs a predetermined operation on the linear color temperature signal or the color temperature signal. 5. The color temperature continuously variable illumination device according to claim 3, wherein a luminance ratio of each emission color with respect to a linear value obtained by performing the above is given. The data table is a data table that gives numerical values corresponding to the luminance ratios instead of the luminance ratios of the respective colors, and the numerical values include the luminous flux ratio, the LED driving duty ratio, the LED driving current or the driving voltage of each color, It is a calculated value by an index or coefficient that can adjust the brightness of the LED such as LED light output,
6. The color temperature continuously variable illumination device according to claim 1, wherein the control unit controls each driving unit based on the corresponding numerical value. A first stage for generating a designated signal corresponding to a designated color temperature or color;
A second step of calculating a luminance ratio of each emission color corresponding to the specified color temperature or color based on the designation signal with reference to a data table of the luminance ratio of each emission color registered in advance;
Based on the calculated luminance ratio of each emission color, each drive unit controls each of the at least one first LED, second LED, and third LED having different emission colors at a predetermined luminance ratio. And a third stage for driving control,
The data table is a data table of luminance ratios of light emission colors for realizing color temperatures or colors at a plurality of points, and the data table is referred to based on the designation signal in the second stage. When the color temperature or color between the points is specified, the luminance ratio of each emission color corresponding to the specified color temperature or color is calculated between these points by linear interpolation. The color temperature continuously variable illumination method. The data table is a data table that gives numerical values corresponding to the luminance ratios instead of the luminance ratios of the respective colors. In the third stage, the LEDs of the respective emission colors are determined based on the corresponding numerical values. Drive control is performed, and the above numerical values are calculated values based on an index or coefficient that can adjust the luminance of the LED, such as the luminous flux ratio of each color, the LED drive duty ratio, the LED drive current or drive voltage, and the LED light output. The color temperature continuously variable illumination method according to claim 7.

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