JPH0696871A - Variable color lighting device - Google Patents

Abstract

(57) [Abstract] [Purpose] To reduce the deviation of the color temperature of illumination light from the setting without increasing the number of light intensity data stored in advance. [Structure] The dimming characteristic converters 8R, 8G, 8B are provided between the dimming signal converter 5 and the dimmers 4R, 4G, 4B. The dimming ratio change width determined by the dimming amount data of each light source stored in advance is input as a dimming signal to the dimming characteristic conversion unit 8B, converted and input to the dimmer 4B.
The dimming characteristic conversion unit 8B reduces the dimming ratio change width when the light source 2B has a low dimming level, and increases the dimming ratio change width when the dimming level is high. This makes it possible to finely set the light amount when the light amount of each of the light sources 2R, 2G, and 2B is small, and it is possible to obtain illumination light with less deviation from the setting without increasing the number of bits of the light amount data.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a variable color lighting device capable of varying a color temperature of illumination light by mixing a plurality of emitted colors.

[0002]

2. Description of the Related Art FIG. 10 is a block diagram of a conventional variable color lighting device of this type.
The light source 2R, 2G, 2B of three colors of green and blue is provided in one fixture body to configure the lighting fixture 1, and each light source 2R, 2G, 2B
Is controlled by the dimmers 4R, 4G and 4B.

The control unit 3 is inserted between the respective light sources 2R, 2G, 2B and the power source AC and dimmed to the dimmers 4R, 4G, 4B for controlling the dimming level of the respective light sources 2R, 2G, 2B. A dimming signal generator 5 that outputs a signal is provided. The dimming level of each light source 2R, 2G, 2B is set by the dimming signal input from the dimming signal generator 5 to each of the dimmers 4R, 4G, 4B.

Further, the dimming signal is obtained by the color temperature of the illumination light obtained by the lighting fixture 1 as a color mixture and the respective light sources 2R, 2G, 2
The light quantity data is output based on the light quantity data in which the correspondence with the light control level of B is set, and the light quantity data is stored in the light quantity data storage unit 6. The plurality of sets of light amount data stored in the light amount data storage unit 6 are selected by operating the illumination light setting unit 7, and each light source 2R, 2G, 2B is selected.
The dimming level of is determined.

The light quantity data storage unit 6 is composed of a memory such as a RAM or a ROM, and each light source 2R, 2G,
The light amount data for 2B is stored as a set of three. That is, the address corresponds to the color temperature, and by designating the address corresponding to the desired color temperature, the light quantity data corresponding to the color temperature is output.

Therefore, the illumination light setting unit 7 stores the light quantity data.
It should be constructed so that the address of the memory 6 can be designated.
For up / down counters and switches
It is composed of Here, the light amount data storage unit 6 stores
The light amount data that is set is set as follows.
The light color of each light source 2R, 2G, 2B is represented by chromaticity coordinates.
(X_R, Y_R), (X_G, Y_G), (X_B, Y_B)
And the light amount of each light source 2R, 2G, 2B is Y
_R, Y_G, Y_BIs the light of the illumination light that is a mixed color
Color (x ₀, Y₀) And the amount of light Y₀Is expressed as
It

X ₀ = {(x _R Y _R / y _R ) + (x _G Y _G / y _G ) + (x _B Y _B / y _B )} / (Y _R / y _R ) + (Y _G / y _G ) + (Y _B / y _B ) y ₀ = (Y _R + Y _G + Y _B ) / {(Y _R / y _R ) + (Y _G / y _G ) + (Y _B / y _B )} Y ₀ = Y _R + Y _G + Y _B By changing the ratio of the light amount of each light source 2R, 2G, 2B, the light color of the illumination light obtained as a color mixture can be changed, and the light amount of each light source 2R, 2G, 2B can be changed. If the light amount is changed while maintaining the ratio, the light amount of the illumination light can be changed. Therefore, the light amount data is created according to the light color of the illumination light, the variable range of the light amount, the specifications of the light source, and the like.

Now, the chromaticity coordinates of the light colors of the respective light sources 2R, 2G and 2B are 2R (0.5537, 0.3300) and 2G.
(0.2946, 0.5503), 2B (0.169
4, 0.1052). Also, the color temperature is 3000K.
It shall be variable in the range of up to 30,000K. Light source 2
One R, 2G, 2B shall be used for each light source 2
If the ratio of the maximum luminous flux of R, 2G, 2B and the set luminous flux Y of the mixed illumination light is 62: 100: 25: Y, the dimming ratio of each light source 2R, 2G, 2B at an arbitrary color temperature is shown in FIG.
It becomes like 1.

As shown in FIG. 11, when the color temperature of the illumination light is high, the dimming level of the light source 2B is higher than that of the light source 2R, and when the color temperature is low, the dimming level of the light source 2R. Is higher than the dimming level of the light source 2B. Thirty
Within the color temperature variable range of 00K to 30000K, the light source 2
G is a dimming level of 50% or more, and the dimming level of 6.76% of the light source 2B at 3000 K is the lowest value.

Now, _assume that the relationship between the dimming signal V _sig input to the dimmers 4R, 4G, and 4B and the dimming ratio is shown in FIG. 12, and the light amount data stored in the light amount data storage unit 6 is shown. 100 steps of dimming (1, 2, 3
··········· 98, 99, 100%). In this case, each light amount data that determines the dimming ratio of each of the light sources 2R, 2G, and 2B may be 7-bit data (0000001 = 1, 1100100 = 1).
00, 1111111 = 128). The relationship between this data and the dimming signal V _sig is shown in FIG.

Although some processing is required for the values below the decimal point of the dimming ratios of the respective light sources 2R, 2G, 2B shown in FIG. 11, here, 0.50 or less is 0.00,
The value of 0.51 or more is set to 1.00. By such processing, the respective light sources 2R, 2G, at the set color temperature shown in FIG.
The dimming ratio of 2B and the illumination light when the colors are actually mixed are as shown in FIG.
As shown in 4. As can be seen from FIG. 14, when the dimming ratio change width of the light amount data is set to 1%, the mixed illumination light color is displaced from the setting.

Further, if the dimming ratio is adjusted in 1% increments with a constant color temperature at the setting of 3000K, the result is as shown in FIG. Here, in calculation, the change width of each dimming ratio of each light source 2R, 2G, 2B is 2R: 0.98%, 2G: 0.68.
%, 2B: 0.07%, but each light source 2R, 2G, 2
The dimming ratio data of B has the values shown in FIG.

Regarding the light source 2B, it should be set to 0.07% in the calculation, whereas it is set to 1% in reality, which means that the setting is considerably rough. In addition, FIG.
From this, it is understood that when light control is performed with the same color temperature, the light color shift increases as the light flux decreases. The reason for this is that, as described above, the dimming ratio change width of the light source 2B is 0.07 in calculation.
This is because, while it must be%, the value is actually 1%. Also, the dimming ratio change width of the light source 2G is not different from that of the light source 2B, but in calculation,
The figure is 0.68%, which is less than 1%. The deviation of the light color is not limited to the setting of 3000K, but appears for all the set color temperatures.

For example, the calculated dimming ratio change width of each of the light sources 2R, 2G, and 2B when the setting is 5000K is 2R: 0.62.
%, 2G: 0.81%, 2B: 0.41%, and 30
When set to 000K, 2R: 0.26%, 2G: 0.5
4% and 2B: 1.00%. From this number,
It can be seen that the largest difference from 1% set as the dimming ratio change width is the dimming ratio change width of the light source 2B at the time of setting 3000K.

[0015]

As a means for solving this problem, there is a method of setting the variation range of the dimming ratio more finely. For example, if the number of dimming steps is increased to 200 and the dimming ratio change width is set to 0.5, the light color shift is smaller than that in the case of 100 steps of dimming. However, in this case, the light quantity data stored in the light quantity data storage unit 6 must be 8-bit data. Further, when the smallest dimming ratio change width of 0.07% is used as a reference in the above description, the number of dimming steps is 1429.
Therefore, 11 bits of light quantity data is required.

Therefore, there is a problem that the smaller the minimum dimming ratio change width, the larger the number of data and the need for a large-capacity storage section. The present invention is provided in view of the above-mentioned point, and by changing the dimming ratio change width of each light source according to the dimming level, it is possible to illuminate without increasing the number of light amount data stored in advance. Provided is a variable color lighting device intended to reduce the deviation of the color temperature of light from the setting.

[0017]

According to the present invention, a light source having a plurality of emission colors, a dimmer for controlling each light source to an arbitrary dimming level, and a dimming amount of each light source are stored as bit data. And a dimming signal conversion unit that converts the bit data from the storage unit into a dimming signal, and a variable color capable of varying the color temperature of the illumination light by mixing the light colors of the light sources. In the lighting device, when the dimming level of each light source is low, the dimming ratio change width is made small, and when the dimming level is high, the dimming ratio change width is processed in an analog manner to obtain a dimming signal. Is provided between the dimming signal converter and the dimmer.

[0018]

The dimming ratio change width determined by the dimming amount data of each light source stored in advance is input as a dimming signal to the dimming characteristic conversion unit and converted to the dimming device. Since the input light is input, the variation range of the dimming ratio is small when the dimming level of each light source is low, and the variation range of the dimming ratio is large when the dimming level is high. As a result, it is possible to finely set the light amount when the light amount of each light source is small, and it is possible to obtain illumination light with a small deviation from the setting without increasing the number of bits of the light amount data.

[0019]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an overall block diagram. As can be seen from FIG. 1, the basic configuration is the same as that of the conventional example, and a lighting fixture 1 composed of RGB light sources 2R, 2G, 2B and light sources 2R, 2G, Dimmers 4R, 4G, 4B that perform 2B dimming
It is composed by.

The dimming level of each of the light sources 2R, 2G and 2B is controlled by the controller 3. The control unit 3 includes a dimming signal generation unit 5, a light quantity data storage unit 6, and an illumination light setting unit 7. When the illumination light of a desired color temperature is desired to be obtained, the illumination light setting unit 7 is operated, The light amount data corresponding to the color temperature is read from the light amount data storage unit 6. The light amount data is input to the dimming signal generator 5 and outputs a dimming signal for setting the dimming level of each of the light sources 2R, 2G, 2B.

The difference between this embodiment and the conventional example is that the control unit 3
The R, G, and B dimming signals are input to the dimming characteristic converting units 8R, 8G, and 8B, respectively, and the dimming characteristic converting units 8R and 8B are input.
The output of G, 8B is input to the dimmers 4R, 4G, 4B. Here, the dimming signal output from the dimming signal generator 5 is set to V _sig, and the dimmer 4 for this V _sig
The dimming characteristic of R, 4G, and 4B is the same as that of FIG. 12 of the conventional example, and the conversion characteristic of V _sig with respect to the light amount data is shown in FIG.
Same as.

The dimming signal V _sig output from the dimming signal generating unit 5 is input to the dimming characteristic converting units 8R, 8G and 8B. In the dimming characteristic converting units 8R, 8G and 8B, The described signal processing is performed. FIG. 2 shows the dimming characteristic conversion unit 8B.
The specific circuit diagram of is shown. Incidentally, another dimming characteristic conversion unit 8
Since the configurations of R and 8G are the same, the dimming characteristic conversion unit 8B will be described.

The dimming signal V _sig is input from the terminal a.
The input dimming signal V _sig is _supplied to the operational amplifier OP ₁ ,
A differential amplifier 10a composed of resistors R ₁ , R ₂ , R ₃ and R _4.
And the input from the operational amplifier OP ₂ and the resistors R _{5 to} R ₈ to the differential amplifier 10b. On the other hand, the differential amplifier 10a
Is input to the differential amplifier 10b, and the voltage Vref set by the reference voltage setting unit 9 is input to the differential amplifier 10b. Therefore, the output of each of the differential amplifiers 10a and 10b is determined by the resistance value, but R ₁ = R ₂ = R ₅ = R ₆ =
When R, R ₃ = R ₄ = αR, and R ₇ = R ₈ = βR are set, the respective outputs V _OP1 and V _OP2 of the operational amplifiers OP ₁ and OP ₂ are expressed by the following equations.

V _OP1 = (αR / R) · (V _sig −0) = αV _sig V _OP2 = (βR / R) · (Vref−V _sig ) = β (V
ref-V _sig ) Here, when α <1, β> 1, Vref = V _sigmax , operational amplifiers OP ₁ and OP ₂ for the dimming signal V _sig are set.
The output characteristics of are as shown in FIG. In the figure, α = 1/3 and β = 2, and the output of the operational amplifier OP ₂ is V by the Zener diode ZD ₁ .
_It does not _{exceed sigmax} .

The output of the operational amplifier OP ₂ is further operational amplifier OP _3, the differential amplifier 1 consisting of resistor R ₉ to R _{1 2}
0c, but the dimming signal V _sig is input to the other input of the differential amplifier 10c. Resistors constituting the differential amplifier 10c, since become _{R 9 = R 1 0 = R} 1 1 = R 1 2, the output of the operational amplifier OP ₃ becomes V _OP3 = V _sig -V _OP2.

The output of the operational amplifier OP _{3 and} the output of the operational amplifier OP ₁ are input to the comparator Com, respectively. The output of the comparator Com is the switch element SW.
₂ is input to the switch SW ₁ via the inverter gate G ₁ , and when V _OP1 > V _{OP 3} , the switch element SW ₂ is turned on, the switch SW ₁ is turned off, and V _OP1 ≦ V
_In the case of _OP3 , switch element SW ₁ is turned on, switch S
Turn off W ₂ .

Therefore, the signal at the output terminal b is as shown in FIG.
As shown in (b), this signal becomes a dimming characteristic conversion unit 8
The B output signal V _sig 'becomes input to the dimmer 4B. By adding such dimming characteristic conversion units 8R, 8G, and 8B, when the dimming level of each of the light sources 2R, 2G, and 2B is low, the dimming ratio change width is small, and when the dimming level is high. The variation range of the dimming ratio becomes large, and the light quantity data is created based on this dimming characteristic.

Here, the minimum dimming ratio change width needs to be set with reference to the calculated minimum dimming ratio change width of each of the light sources 2R, 2G, and 2B in the conventional example. That is, in the configuration described in the conventional example, the minimum dimming ratio change width is 0.07%, but the minimum dimming ratio change width after the dimming characteristic conversion is 0.0
The value is set to a value close to 7% so that the deviation of the illumination light color temperature cannot be recognized by a person.

As described above, by converting the dimming characteristics and setting the minimum dimming ratio change width, the amount of light amount data remains the same as before, and the light amount setting of each light source 2R, 2G, 2B is performed. Since it can be performed with a value close to the calculated value, it is possible to obtain illumination light with less deviation from the setting. In the description of the present embodiment, 0.07% of the minimum dimming ratio change width of the light source 2B is used as a reference, but this is based on each light source 2 having R, G, B light colors.
This is not limited to a light source having a blue light color, because it depends on the maximum luminous flux ratio of R, 2G, and 2B and the number of rays, and the setting of the variable range of the color temperature also affects.

Although the dimming signal is also described as a DC voltage,
Anything such as a duty signal, a phase control signal, etc., for example,
In the case of a duty signal, DC proportional to the duty ratio
Signal conversion for outputting a voltage may be performed. Further, the light color of the light source is not limited to R, G, B, but yellow (Y), white, or the like may be used. Also, the power consumption of the light sources need not be the same,
A light source with low power consumption may be used.

As described above, the dimming characteristic for the dimming signal V _sig is linear (FIG. 12).
As shown in FIG. 4A, the output signal V _sig ′ of the dimming characteristic conversion unit shown in FIG. 4B is obtained by this embodiment even in the case of the nonlinear characteristic. (Embodiment 2) FIG. 5 shows Embodiment 2, which is different from the previous embodiment in the structure of the dimming characteristic conversion unit. The operation will be described below.

In FIG. 5, the dimming signal V _sig is input from the terminal a. The dimming signal V _sig is a differential amplifier 10a which is composed of an operational amplifier OP ₁ and resistors R _{1 to} R _4.
Entered in. On the other hand, the other input of the differential amplifier 10a receives the voltage V _ref1 set by the reference voltage setting unit 9a.
Has been entered. Here, it is assumed that V _ref1 = V _sigmax .
Output V _OP1 of operational amplifier OP ₁ for dimming signal V _sig
Is as shown in FIG.
It is an input to the adder 11 which is composed of P ₂ and resistors R _{5 to} R ₈ . The other input of the adder unit 11 is connected to the reference voltage setting unit 9
is the reference voltage V _ref2 set in b, where:
This reference voltage V _{ref2 is set} to 1. The output voltage V _OP2 of the operational amplifier OP ₂ is V _OP2 = {(1 / R ₁₆ ) + (1 / R ₁₇ )} · {1+ (R ₁₈ / R ₁₅ )} · {(V _OP1 / R ₁₇ ) + ( Each resistance value is set so that 1 / R ₁₆ )} = V _OP1 +1. The output V _OP2 of the operational amplifier OP ₂ for the dimming signal V _sig is also shown in FIG.
It shows in (a).

The output of the operational amplifier OP ₂ is input to the logarithmic converter 12. The logarithmic converter 12 has the input / output characteristic as shown in FIG. Therefore, the output V of the logarithmic conversion unit 12 with respect to the dimming signal V _{sig
The log} is as shown in FIG. Incidentally, FIG. 6 (b)
(C) is not on a logarithmic scale. Then, the output V _log of the logarithmic conversion unit 12 and the set voltage V of the reference voltage setting unit 9a
_{sigm ax} includes an operational amplifier OP _3, the input of the configured differential amplifier 10b by a resistor R ₉ ~R _{1 2.}

Where R₉= R_Ten= R_{1 1}= R_{1 2}When
Then, the operational amplifier OP₃Output V _OP3Is V_OP3= V_sigmax-V_log And the dimming signal V_sigOutput V for_OP3In Figure 7.
As shown. As described above, the light sources 2R and 2R of the above-described embodiments
It was explained that the dimming characteristics of G and 2B are the same.
The light control characteristics of each light source 2R, 2G, 2B.
It may be set based on the dimming ratio change width of 2R, 2G, 2B.
As shown in Fig. 9, only the dimming characteristics of one light source are converted.
You may go. In the case of FIG. 9, compared to the above embodiments, the light
Although the color shift is large, the light color shift is improved compared to the conventional example.
Have been good.

[0035]

As described above, the present invention stores a light source having a plurality of emission colors, a dimmer for controlling each light source to an arbitrary dimming level, and a dimming amount of each light source as bit data. And a dimming signal conversion unit that converts the bit data from the storage unit into a dimming signal, and a variable color capable of varying the color temperature of the illumination light by mixing the light colors of the light sources. In the lighting device, when the dimming level of each light source is low, the dimming ratio change width is made small, and when the dimming level is high, the dimming ratio change width is processed in an analog manner to obtain a dimming signal. Since the dimming characteristic conversion unit for outputting is provided between the dimming signal conversion unit and the dimmer, the dimming ratio change width determined by the dimming amount data of each light source stored in advance is As a dimming signal, it is input to the dimming characteristics conversion unit and converted and adjusted. Since the input to the vessel, when the dimming level of each light source is low, the dimming ratio change width is small, the dimming level becomes large dimming ratio change width is higher. As a result, it is possible to finely set the light amount when the light amount of each light source is small, and it is possible to obtain the illumination light with less deviation from the setting without increasing the number of bits of the light amount data.

[Brief description of drawings]

FIG. 1 is an overall block diagram of an embodiment of the present invention.

FIG. 2 is a specific circuit diagram of the dimming characteristic conversion unit of the above.

FIG. 3A is a diagram showing a relationship between a dimming signal and an output of an operational amplifier in the above. (B) is a figure which shows the relationship between the dimming signal and the output of a dimming characteristic conversion part same as the above.

FIG. 4A is a diagram showing a relationship between a dimming signal and a dimming ratio when the dimming characteristic of the same is non-linear. FIG. 6B is a diagram showing the relationship between the dimming signal and the output of the dimming property converter when the dimming property is non-linear.

FIG. 5 is a specific circuit diagram of another embodiment of the dimming characteristic conversion unit of the above.

FIG. 6A is a diagram showing the relationship between the dimming signal and the output of the operational amplifier in the above. (B) is a figure which shows the relationship of the input and output of the logarithmic conversion part same as the above. (C) is a figure which shows the relationship between the dimming signal and the output of a logarithmic conversion part same as the above.

FIG. 7 is a diagram showing the relationship between the dimming signal and the output of the operational amplifier in the above.

FIG. 8 is a diagram showing a relationship between a dimming signal and an output of a dimming characteristic conversion unit of the above.

FIG. 9 is a diagram showing a relationship between a dimming signal and an output of a dimming characteristic conversion unit of the above.

FIG. 10 is a block diagram of a conventional variable color lighting device.

FIG. 11 is a diagram showing a dimming ratio of each light source at an arbitrary color temperature of the same.

FIG. 12 is a diagram showing a relationship between a dimming signal and a dimming ratio in the same as above.

FIG. 13 is a diagram showing a relationship between light intensity data and a dimming signal for determining a dimming ratio of each light source of the same.

FIG. 14 is a diagram showing a dimming ratio of each light source at a predetermined set color temperature and illumination light in the case of actually mixing colors.

FIG. 15 is a diagram showing illumination light when dimming is performed at a dimming ratio of 1% while maintaining a constant color temperature at the same setting of 3000K.

[Explanation of symbols]

 1 Lighting fixture 2R, 2G, 2B Light source 4R, 4G, 4B Dimmer 5 Dimming signal generator 6 Light intensity data storage 8R, 8G, 8B Dimming characteristic converter

Claims (1)

[Claims] 1. A light source having a plurality of emission colors, a dimmer that controls each light source to an arbitrary dimming level, a storage unit that stores the dimming amount of each light source as bit data, and the storage unit. And a dimming signal conversion unit that converts the bit data from the light source into a dimming signal, and by adjusting the color temperature of the illuminating light by mixing the light colors of the light sources, A dimming characteristic conversion unit that outputs a dimming signal by analog processing so that the dimming ratio change width is small when the light level is low, and is large when the dimming level is high. Is provided between a dimming signal conversion unit and a dimmer.