JP2009274657A - Illuminating device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an illuminating device which can accurately compensate for illuminance variation with time in a semi-conductor light emitting element. <P>SOLUTION: The illuminating device is configured to supply power for lighting from power conversion means 15a to 15c independently to each of a plurality of semi-conductor light emitting elements 11a to 11c of different light emitting colors. A target value creating means 13 carries out illuminance compensation based on accumulated real lighting time which is accumulation of product of lighting time and light modulation rate for each respective semi-conductor light emitting element 11a to 11c and creates a power target value for lighting for supplying to each respective semi-conductor element 11a to 11c at compensated illuminance so that mixed color light which is set by a color setting means 12 may be obtained. A control means 14 controls power conversion means 15a to 15c so that power for lighting which is supplied to each respective semi-conductor light emitting element 11a to 11c may reach the power target value for lighting which is created by the target value creating means 13. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an illumination device that has a plurality of light-emitting semiconductor light-emitting elements and performs spatial illumination with a desired light-emitting color by mixing the light colors of these semiconductor light-emitting elements.

  The demand for variable color control of illumination light by an illuminating device has been increasing from the improvement of stage performance in stores and theaters. In addition, interest in comfortable space illumination is increasing due to the relationship between illumination light and physiological phenomena.

  On the other hand, with the recent increase in efficiency of semiconductor light emitting elements, the three primary colors of light can be emitted with high efficiency by the semiconductor light emitting elements, and an illumination device using three semiconductor light emitting elements of the three primary colors has been adopted. It has become so. In this case, each of the three semiconductor light emitting elements of the three primary colors is lit in a dimming state, and variable color control is performed to a desired color.

  Here, the illuminance is detected for each colored light emitted by a single light emitting diode for a plurality of light emitting diodes (LEDs), and the power to each light emitting diode is corrected so that the detected illuminance matches the reference value. Even when a different secular change occurs for each colored light, there is one in which the illuminance change and the color change of the mixed color light are easily and quickly reduced (see, for example, Patent Document 1).

That is, in Patent Document 1, when the illuminance of a plurality of light emitting diodes is detected by an optical sensor, the illuminance characteristics with respect to the emission time from the initial stage to the end of the life are stored in advance, and the detected illuminance is different from the reference value Sets a power correction value for each predetermined emission time until the end of life based on the detected value and illuminance characteristics, and supplies the light emitting diode with the correction value every time the predetermined emission time elapses The power to be corrected is corrected.
JP 2007-80540 A

  However, in Patent Document 1, based on the emission time of the light emitting diode and the illuminance characteristics with respect to the emission time from the initial stage to the end of life, the power supplied to the light emitting diode is corrected to correct the illuminance due to the secular change of the light emitting diode. Therefore, since the dimming rate of the light emitting diode is not taken into consideration, accurate correction cannot be obtained. This is because the light emitting diode has a characteristic that the lifetime increases as the integrated value of the flowing current is suppressed, so that the secular change of the light emitting diode is greatly related not only to the emission time but also to the dimming rate.

  Thus, in what calculates | requires the secular change of a light emitting diode only by the cumulative lighting time (emission time) from the time of starting energization for the first time, since the cumulative electric power input by the light control rate of a light emitting diode differs, As a result, the degree of deterioration for each light color also varies. For this reason, only a correction amount different from the actual correction amount can be obtained.

  The objective of this invention is providing the illuminating device which can correct | amend the temporal change of the illumination intensity of a semiconductor light-emitting element accurately.

  The lighting device according to claim 1 is a power conversion means for supplying lighting power independently to each of a plurality of semiconductor light emitting elements having different emission colors; and a mixed color of the plurality of semiconductor light emitting elements is set. Color setting means for performing illuminance correction based on an illuminance correction curve represented by a function of accumulated substantial lighting time obtained by accumulating the product of the lighting time and the dimming rate of each semiconductor light emitting element, and setting by the color setting means Target value creating means for creating a target power value for lighting to be supplied to each semiconductor light emitting element with the illuminance corrected so as to obtain a mixed light color; and the lighting power to be supplied to each semiconductor light emitting element is the target value And a control means for controlling the power conversion means so as to become the lighting power target value created by the creation means.

  In the present invention and the following inventions, definitions and technical meanings of terms are as follows. The different emission colors are, for example, the three primary colors of light, red (R), green (G), and blue (B). The plurality of semiconductor light emitting elements in this case are a red (R) semiconductor light emitting element, a green (G) semiconductor light emitting element, and a blue (B) semiconductor light emitting element. The semiconductor light emitting element includes, for example, a light emitting diode and organic EL (organic electroluminescence). The lighting power is direct current power converted by the power conversion means for lighting the semiconductor light emitting element, and a direct current is supplied to the semiconductor light emitting element. “Independently supplying lighting power” means that lighting power is supplied from individual power conversion means for each semiconductor light emitting element.

  The color setting means sets a light emission color obtained by mixing light emission colors of a plurality of semiconductor light emitting elements. The mixed color of a plurality of semiconductor light emitting elements is, for example, when the plurality of semiconductor light emitting elements are a red (R) semiconductor light emitting element, a green (G) semiconductor light emitting element, and a blue (B) semiconductor light emitting element. Means an emission color obtained by mixing these three primary colors.

  The lighting time is a time during which the semiconductor light emitting element is lit in either a dimming state or an all-light state. The cumulative substantial lighting time is a cumulative lighting time obtained by accumulating the product of the lighting time of the semiconductor light emitting element and the dimming rate during lighting for each semiconductor light emitting element.

  Illuminance correction means correcting the illuminance of each semiconductor light emitting element to the illuminance for lighting control, and the illuminance correction curve represents the actual illuminance of the semiconductor light emitting element from the initial stage to the end of life for each semiconductor light emitting element. In order to keep it constant, it is shown as a function of the cumulative real lighting time. The lighting power target value is a target value of lighting power for lighting each semiconductor light emitting element so as to have a corrected illuminance.

  A lighting device according to a second aspect of the present invention is the lighting device according to the first aspect, wherein the semiconductor light emitting element is a light emitting diode, and the control means detects the illuminance of the light emitting diode during light emission. The power conversion means is controlled so that the lighting time is turned on with a phase difference and a rest period, and the illuminance of the light emitting diode that is emitting light by the light emitting diode in the rest period is detected, and the target value creating means is detected The illuminance correction curve is modified so that the illuminance thus obtained becomes a reference value.

  The rest period is a section in which the light emitting diodes are not lit. When the lighting time of each light emitting diode is turned on with the rest period, the rest period is generated when lighting control of each light emitting diode is performed. It means to light up intermittently.

  In addition, when the lighting time of each light emitting diode is turned on with a phase difference and a pause period, each of the light emitting diodes for illuminance detection is in a pause period in the section in which the light emitting diode to be detected is illuminated. The light emitting diode is turned on with a phase difference.

  Detecting the illuminance of a light emitting diode that is emitting light with a light emitting diode in a rest period means that the light emitting diode that is not lit is used as an illuminance sensor and the illuminance of the light emitting diode that is the illuminance detection target that is lit is detected. Say.

  According to the first aspect of the present invention, the product of the lighting time and the dimming rate is calculated for each of the semiconductor light emitting elements of different emission colors to obtain the accumulated substantial lighting time, and based on the accumulated actual lighting time, Since the correction with respect to the change in illuminance with time is performed, the illuminance of the semiconductor light emitting element can be corrected with high accuracy.

  According to the invention of claim 2, the light emitting diode which is a semiconductor light emitting element is intermittently turned on and the light emitting diode which is in a non-lighting state is used as an illuminance sensor, and the illuminance of the light emitting diode in the lighting state is detected, Since the illuminance correction curve is corrected so that the detected illuminance becomes the reference value, the illuminance correction of the light emitting diode can be corrected with the actually measured illuminance. Therefore, the illuminance of the light emitting diode can be corrected with higher accuracy.

  FIG. 1 is a configuration diagram of Example 1 of the lighting apparatus according to the embodiment of the present invention. In the following description, a case where the semiconductor light emitting element of the light source unit of the lighting device is a light emitting diode will be described. The light source unit of the illuminating device includes a red light emitting diode 11a, a green light emitting diode 11b, and a blue light emitting diode 11c that emit light of the three primary colors of light, and these three primary colors are red (R) and green (G). , Blue (B) is mixed to output a desired color.

  The color setting unit 12 sets a mixed light color in which red, green, and blue are mixed, and sets a desired color by setting the ratio of illuminance of red, green, and blue. For example, when red (0%), green (0%), and blue (100%) are used, a blue emission color is obtained. The color setting set by the color setting means 12 is input to the target value creating means 13.

  The target value creating means 13 sets the power target values for lighting of the red light emitting diode 11a, the green light emitting diode 11b, and the blue light emitting diode 11c so as to satisfy the red, green, and blue illuminance ratios set by the color setting means 12. create. The lighting power target values of the respective light emitting diodes 11 a, 11 b, 11 c created by the target value creating means 13 are input to the control means 14.

  The control unit 14 controls the power conversion units 15a, 15b, and 15c so that the lighting power supplied to the respective light emitting diodes 11a, 11b, and 11c becomes the lighting power target value created by the target value creating unit 13. The power converters 15a, 15b, and 15c adjust the power from the power source 16 and supply the lighting power independently to each of the light emitting diodes 11a, 11b, and 11c.

  FIG. 2 is a graph showing an example of the relationship between the corrected illuminance used in the illuminance correction by the target value creating means 13 and the accumulated substantial lighting time. In the illuminance correction curve S, in the initial stage of the light emitting diode 11, a predetermined illuminance (for example, 80% illuminance) in a dimming state is set to all light (100%). Then, as the accumulated substantial lighting time obtained by accumulating the product of the lighting time of the light emitting diodes and the dimming rate becomes longer (larger), the illumination control illumination intensity is made closer to the actual total light (100%). . The illuminance correction curve S is prepared for each light emitting diode 11a, 11b, 11c according to the characteristics of each light emitting diode 11a, 11b, 11c.

  Further, the target value creating means 13 calculates the dimming rate and lighting time of each light emitting diode 11a, 11b, 11c from the lighting time of each mixed color and each illuminance ratio, and for each light emitting diode 11a, 11b, 11c. The product of the dimming rate and the lighting time is calculated, and the accumulated substantial lighting time of each light emitting diode 11a, 11b, 11c is constantly updated and stored.

  For example, when the cumulative effective lighting time t of the light emitting diode 11a is ta, and setting that the illuminance ratio of the light emitting diode 11a is 40% is input from the color setting unit 12, as shown in FIG. Since the corrected illuminance at the cumulative substantial lighting time ta is A from the illuminance correction curve S, the target value creating means 13 calculates a lighting power target value such that the illuminance is 0.4 × A. The control unit 14 controls the power conversion units 15a, 15b, and 15c so that the lighting power supplied to the respective light emitting diodes 11a, 11b, and 11c becomes the lighting power target value created by the target value creating unit 13.

  As described above, according to the first embodiment, the product of the lighting time and the dimming rate is calculated for each of the light emitting diodes 11a, 11b, and 11c having different light emission colors to obtain the cumulative substantial lighting time, and the cumulative substantial lighting time is obtained. Based on this, the illuminance of the light emitting diode can be corrected with high accuracy because the illuminance of the light emitting diode is corrected with time. In the above description, the semiconductor light emitting element of the light source unit is described as a light emitting diode, but may be an organic EL.

  FIG. 3 is a configuration diagram of Example 2 of the lighting apparatus according to the embodiment of the present invention. This Example 2 uses a light emitting diode as a semiconductor light emitting element and adds a function of detecting the illuminance of a light emitting diode that is turned on by a light emitting diode in a non-lighted state to the Example 1 shown in FIG. is there. The same elements as those in FIG. 1 are denoted by the same reference numerals, and redundant description is omitted.

  In general, when a light emitting diode is in a non-lighting state, when light is irradiated, an electromotive force is generated in accordance with the amount of light irradiated, and thus the illuminance can be detected by detecting the voltage. Accordingly, each of the light emitting diodes 11a, 11b, and 11c is used as an illuminance sensor, and the illuminance detected by each of the light emitting diodes 11a, 11b, and 11c is input to the control means 14 as shown in FIG.

  When the control means 14 detects the illuminance of the light emitting diodes during light emission, the power conversion means 15a, 15b, so that the lighting times of the respective light emitting diodes 11a, 11b, 11c are turned on with a phase difference and a rest period. 15c is controlled.

  For example, the red light emitting diode 11a is a light emitting diode for detecting illuminance of the green light emitting diode 11b, the green light emitting diode 11b is a light emitting diode for detecting illuminance of the blue light emitting diode 11c, and the blue light emitting diode 11c is for detecting the illuminance of the red light emitting diode 11a. When the illuminance of the green light-emitting diode 11b is detected by the red light-emitting diode 11a in advance, when the green light-emitting diode 11b is lit, a rest period (non-lighting period) is provided in the red light-emitting diode 11a. Provide.

Further, when the illuminance of the blue light emitting diode 11c is detected by the green light emitting diode 11b, a pause period (non-lighting period) is provided in the green light emitting diode 11b when the blue light emitting diode 11c is lit.

Similarly, when the illuminance of the red light emitting diode 11a is detected by the blue light emitting diode 11c, a pause period (non-lighting period) is provided in the blue light emitting diode 11c when the red light emitting diode 11a is turned on.

  FIG. 4 is a characteristic diagram of lighting control when the illuminance of the light emitting diode is detected by the control means 14. For example, when the illuminance of the green light emitting diode 11b is detected by the red light emitting diode 11a, the control means 14 uses the green light emitting diode 11b in the rest period ΔT3 from the time t5 to t7 of the non-lighting period of the red light emitting diode 11a. During the only lighting period ΔT3 ′, the illuminance of the green light emitting diode 11b is detected by the red light emitting diode 11a. In addition, when the illuminance of the blue light emitting diode 11c is detected by the green light emitting diode 11b, the control unit 14 detects the blue light emitting diode 11c in the rest period ΔT1 from the time t1 to t4 of the non-lighting period of the green light emitting diode 11b. During the only lighting period ΔT1 ′, the green light emitting diode 11b detects the illuminance of the blue light emitting diode 11c. Similarly, when the illuminance of the red light emitting diode 11a is detected by the blue light emitting diode 11c, the control means 14 uses the red light emitting diode during the rest period ΔT2 of the non-lighting period t3 to t6 of the blue light emitting diode 11c. During the lighting period ΔT2 ′ of only 11a, the blue light emitting diode 11c detects the illuminance of the red light emitting diode 11a.

  Then, the control means 14 inputs the detected illuminance of each light emitting diode 11a, 11b, 11c to the target value creating means 13, and the target value creating means 13 detects the illuminance of each detected light emitting diode 11a, 11b, 11c. The illumination correction curve is corrected so that becomes the reference value. That is, the illuminance correction curve S shown in FIG. 2 is corrected.

  In this manner, the output power for lighting to each of the light emitting diodes 11a, 11b, and 11c is intermittently matched to the color mixture, and the illuminance is detected during the pause period. Further, the intermittent frequency is set to a frequency higher than that of flickering when it is lit, so that it appears to be lit continuously.

  According to the second embodiment, it is possible to detect the illuminance of the light emitting diode in the lighting state without providing an illuminance sensor separately. Further, since the illuminance correction curve is corrected so that the detected illuminance becomes the reference value, the illuminance correction of the light emitting diode can be corrected with the actually measured illuminance. Therefore, the illuminance of the light emitting diode can be corrected with higher accuracy.

The block diagram of Example 1 of the illuminating device concerning embodiment of this invention. The graph which shows an example of the relationship between the correction | amendment illumination intensity used in the case of the illumination intensity correction | amendment in the target value preparation means in embodiment of this invention, and accumulated substantial lighting time. The block diagram of Example 2 of the illuminating device concerning embodiment of this invention. The characteristic diagram of lighting control in the case of detecting the illumination intensity of a light emitting diode with the control means in embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 ... Light emitting diode, 12 ... Color setting means, 13 ... Target value preparation means, 14 ... Control means, 15 ... Power conversion means, 16 ... Power supply

Claims (2)

Power conversion means for independently supplying lighting power to each of a plurality of semiconductor light emitting elements of different emission colors;
Color setting means for setting a mixed color of a plurality of semiconductor light emitting elements;
The illuminance correction is performed based on the illuminance correction curve indicated by the function of the cumulative substantial lighting time obtained by accumulating the product of the lighting time and the dimming rate of each semiconductor light emitting element, and the mixed light color set by the color setting means is obtained. Target value creating means for creating a power target value for lighting to be supplied to each semiconductor light emitting element with the corrected illuminance;
Control means for controlling the power conversion means so that the lighting power supplied to each semiconductor light emitting element becomes the lighting power target value created by the target value creating means;
An illumination device comprising:   The semiconductor light emitting element is a light emitting diode, and when the control means detects the illuminance of the light emitting diode that is emitting light, the lighting time of each light emitting diode is turned on with a phase difference and a rest period. The power conversion means is controlled to detect the illuminance of the light emitting diode that is emitting light by the light emitting diode in the pause period, and the target value creating means corrects the illuminance correction curve so that the detected illuminance becomes a reference value. The lighting device according to claim 1.

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