JP2006135007A - Light emitting element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light emitting element comprising a plurality of light emitting diodes and their driving IC integrally, and including at least three primary colors of red (R), green (G) and blue (B) wherein not only white light but also arbitrary color light can be emitted and the emission intensity and chromaticity of a large number of light emitting elements can be matched easily with no variation regardless of temperature variation. <P>SOLUTION: The light emitting element 1 integrates a plurality of light emitting diodes 2R, 2G and 2B and their driving IC3. The driving IC3 comprises current supply circuits 11-1 to 11-3 with temperature compensation circuits 20-1 to 20-3 and supplies a temperature compensated driving current to each light emitting diode through the driver 19R, 19G, 19B thereof. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a light emitting device such as a lamp type or a chip type, which is integrally provided with a plurality of light emitting diodes and their driving ICs, and in particular, a plurality of light emitting diodes and their driving ICs are integrally provided, and at least red (R) , Including green (G) and blue (B) primary colors, it can emit not only white light but also any color, and the light emission intensity and chromaticity characteristics of many light-emitting elements are easy regardless of temperature changes. The present invention relates to a light-emitting element that can be matched with no variation.

  Conventionally, Patent Document 1 discloses a light-emitting element that can emit pseudo white light by combining a light-emitting diode and a phosphor that emits light of a color complementary to the light-emitting diode. In this case, generally, a light emitting diode that emits blue light is used, and a phosphor that absorbs blue light and emits yellow light is combined so that the human eye can feel white light in a pseudo manner. Is frequently used. However, since there are few specific color components in such a combination, that is, when there is a mixture of blue and yellow as described above, there are few red components, so that when used as a backlight for an LCD, the color reproduction range is small. There is a problem of being narrow. There is also a problem of lack of color rendering.

  As another method of emitting white light, an example using a mixed color of three primary colors using a light emitting diode that emits R, G, and B light is also known. However, when white light is emitted by mixing three primary colors, for example, as is apparent from the light emission intensity-forward current characteristics of various typical light emitting diodes shown in FIG. 22, the light emitting diodes emit R, G, and B light. Since there is a large difference in the electro-optical characteristics, current adjustment for adjusting the light emission degree of each color becomes very troublesome.

  Further, even in cases other than white light emission, it is also necessary to obtain a desired color and light emission intensity distribution by using a plurality of light emitting diodes of three colors of R, G and B or different colors. It is necessary to adjust the emission intensity of the light, but current adjustment for this is troublesome. In addition, this current adjustment can be adjusted by an external circuit, but in that case, it is necessary to provide an external circuit for each light emitting element, and the circuit configuration becomes complicated and chromaticity, etc. There is a problem that the adjustment becomes complicated.

  Conventionally, a so-called multichip type full color light emitting element in which light emitting diodes of the three primary colors of R, G, and B are integrated has four terminals with an anode or a cathode as a common terminal, or three color light emitting diodes are independent. As terminal light-emitting elements, various shapes (chip-type light-emitting diodes, lamps, image display devices, etc.) have been put into practical use. In this case, by controlling the current supplied to each light emitting diode from the outside, the emission color of R, G, B monochromatic emission or mixed light (R + G, R + B, R + G + B, etc.) is controlled. There is a problem that it is necessary to set a current value determined for each, and the control from the outside is complicated.

  Even when the current supplied from the outside is controlled, characteristics such as R, G, and B emission intensity and chromaticity are likely to vary due to variations in the characteristics of each light emitting element. There is a problem that the obtained light emission intensity and chromaticity (particularly white chromaticity) also vary.

  In addition, white light using a mixed color of three primary colors using light emitting diodes that emit R, G, and B light has emission spectra of R and G as shown in the spectrum distribution characteristic diagram of various light emitting diodes in FIG. Since the interval between is wider than the interval between the emission spectra of G and B, there is a region where the emission spectrum distribution is discontinuous between R and G. Therefore, in order to obtain white light with higher color rendering properties, not only the light emitting diodes of the three primary colors R, G, and B, but also the orange (O) and yellow (Y) light emission spectrum distribution located between R and G At least one of the light-emitting diodes is further used. However, it becomes more difficult to correct variations in chromaticity of light-emitting elements in which these light-emitting diodes are made into a multichip.

  In addition, it is a common practice to form a light-emitting device or an image display device by combining a plurality of light-emitting elements in which a plurality of light-emitting diodes are made into a multi-chip. Since the number of elements is very large, the problem of the above-described correction of chromaticity variation appears more greatly.

  The inventor of the present application eliminates the complexity of color control and circuit configuration in the multi-chip type light emitting element as described above, and enables emission control of multicolor light and white light by a simple driving method. In addition, Japanese Patent Application No. 2004-222467 (hereinafter referred to as “Japanese Patent Application No. 2004-222467”) relates to a light-emitting element having a configuration that can easily and accurately control variation in white chromaticity obtained from each of R, G, and B light-emitting diodes. A patent application has been filed as “prior application”))).

  In order to understand the invention of the present application, first, the light emitting element of the prior invention will be described with reference to FIGS. FIG. 24 is an equivalent circuit diagram showing the internal configuration of the driving IC of the light emitting element 10A of the prior invention in a block diagram, and FIG. 25 is a diagram showing a specific example of the internal circuit of the driving IC of FIG. FIG. 26 is a timing chart for explaining the operation of the driving IC of FIG.

  As shown in FIGS. 24 and 25, the light emitting element 10A of the prior application invention has three primary colors of red (R), green (G), and blue (B) as the plurality of light emitting diodes 2 to emit white light. The three light emitting diodes 2R, 2G, and 2B having the emission colors are used, and the driving IC 3A and the light emitting circuit that is connected to each of the light emitting diodes 2R, 2G, and 2B are connected between the two external terminals 5 and 6 And the light emission intensity of each of the light emitting diodes 2R, 2G, 2B is controlled by a control signal from the external terminals 7CR, 7CG, 7CB.

  The driving IC 3A for the light emitting element 10A of the prior application includes a current supply circuit 11, a correction circuit 17, various signal control circuits 18, and a plurality of bit drivers 19, and the correction circuit 17 is a nonvolatile data memory for correction. It has a sex memory.

  The correction circuit 17 stores 3 bits, that is, eight levels of correction levels by a 3 × 3 bit nonvolatile memory, and outputs various levels corresponding to the selected correction level to various signal control circuits 18. Then, a predetermined corrected current is supplied to each of the light emitting diodes 2R, 2G, and 2B.

The various signal control circuits 18 include three signal control circuits 18R, 18G, and 18B corresponding to the respective light-emitting diodes 2R, 2G, and 2B. Each signal control circuit 18R, 18G, and 18B emits green light, for example. taking as an example the one for the diode 2G driving, two inverting circuit and the waveform shaping circuit 18G ₁ connected in series, the drive signal from the output and the external input terminal 7CG from the correction circuit 17 and outputs three take The AND circuits 18G _{2 to} 18G ₄ are provided, and the waveform shaping circuits and outputs of the AND circuits 18G _{1 to} 18G ₄ are input to the corresponding driver circuits 19G ₁ to 19G ₄ of the driver 19G, and the respective driver circuits 19G _{1 to} 19G. The output of ₄ is connected in parallel and supplied to the corresponding green light emitting diode 2G.

  The signal control circuits 18R and 18B for driving the red light emitting diode 2R and the blue light emitting diode 2B and the drivers 19R and 19B have the same configuration as the signal control circuit 18G and driver 19G for driving the green light emitting diode 2G. However, illustration is omitted.

  The adjustment of the emission color of the light emitting element 10A is performed by the following method. First, an average current value TYP for obtaining white light is obtained from the light emission intensity-forward current characteristics of each of the plurality of light-emitting diodes 2R, 2G, and 2B. In consideration of the current value, for example, every 5%, eight levels of current values of + 20%, + 15%, + 10%, + 5%, TYP, −5%, −10%, and −15% are determined. .

The driver 19G supplies a current value corresponding to −15% as the output current of the driver circuit 19G ₁ driven only by the drive signal from the external input terminal 7CG, and the other three driver circuits 19G _2. ～19G ₄ respectively correspond to the predetermined current interval of the + 5% portion, so as to supply + 10% min and + 20% of the current.

Then, the light emitting diode 2G, the output to the output terminal corresponding to the external input terminal 7CG appears always with the current corresponding to the -15% of the from the driver circuit 19G ₁ is supplied, stored in the correction circuit 17 Since the output currents from the other three driver circuits 19G _{2 to} 19G ₄ are simultaneously supplied according to the output based on the data, the current value supplied to the light emitting diode 2G is −10% with the minimum value being −15%. %, -5%, TYP, + 5%, + 10%, + 15%, + 20%.

  By adopting such a configuration, a predetermined correction is made to the correction circuit 17 so that a predetermined corrected current can be supplied to each of the light emitting diodes 2R, 2G, and 2B during or after the assembly of the light emitting element 10A. If the data is stored, a predetermined corrected current value can be supplied to each of the light emitting diodes 2R, 2G, and 2B.

  The operation of this driving IC 3A is as shown in the timing chart of FIG. That is, when the power supply voltage is supplied and the drive signals CR, CG, and CB as shown in FIG. 26 are supplied to the external input terminals 7CR, 7CG, and 7CB, the light emitting diodes are based on the red light emitting diode drive signal CR. Similarly, an output current (R) is supplied to 2R, and similarly, an output current (G) for light emission is supplied to the light emitting diode 2G based on a green light emitting diode drive signal CG. Based on the signal CB, the light emitting output current (B) is supplied to the light emitting diode 2B.

  Therefore, since the drive circuits of the respective light emitting diodes 2R, 2G, and 2B are independent, when any two signals of the drive signals CR, CG, and CB are input at the same time, the combined light has a predetermined chromaticity. When all of the drive signals CR, CG, and CB are input to the light emitting element 1 at the same time, desired white light in which all the light emitting components are combined can be obtained. As described above, at least W, R, G, B, RG, RB, and GB can be expressed by the on / off control of the drive signals CR, CG, and CB, but the CR, CG, and CB are turned on and off. By changing the off-time and timing, it is possible to represent nearly infinite colors of 7 colors or more.

Note that the SET terminal 7SE in FIGS. 24 and 25 is provided for switching between the normal lighting mode and the correction data storage mode, and once the correction data is stored in the nonvolatile memory of the correction circuit 17. After that, the correction data can be deleted so as not to be changed.
JP 2001-217463 A JP 2002-369506 A Japanese National Patent Publication No. 10-508984

  According to the above-mentioned prior application, it is possible to obtain white light with high chromaticity accuracy by easily correcting the variations in the emission intensity and chromaticity of the R, G, B full-color light emitting elements from the outside. It plays. However, once white light with high chromaticity purity is obtained by correcting the emission intensity and variation of the R, G, B full-color light emitting elements, it is gradually increased based on the temperature rise of the light emitting elements and changes in the ambient temperature during use. It was recognized that variations and changes in emission intensity and chromaticity occurred.

  Such a feature is not noticeable when a full-color light-emitting element is used alone or when there is a color change, but in applications where a plurality of full-color light-emitting elements are continuously arranged, a slight emission intensity Even if there is a variation in chromaticity, the result is very conspicuous, and a satisfactory result cannot always be obtained. In particular, the change in chromaticity accompanying a change in temperature is conspicuous and can be a serious problem.

  For example, in a VGA type image display device, 640 dots × 480 dots = about 300,000 R, G, B full-color light emitting elements are used, but one of these about 300,000 may be used. If there is a variation in the light emission intensity and chromaticity of the R, G, B full-color light emitting elements, especially when displaying white, only the light emitting elements are very conspicuous. Therefore, there is a demand for R, G, B full-color light emitting elements that can easily adjust the variations in light emission intensity and chromaticity of a large number of such R, G, B full color light emitting elements from the outside.

  The inventor of the present application has conducted various experiments in order to solve the problems of the prior application, and as a result, for example, as shown in FIG. There is a difference, and the change in emission intensity due to temperature change of green and blue light emitting diodes is almost the same, but especially the emission intensity of red light emitting diodes decreases greatly with increasing temperature, and as a result, the mixed light rises in temperature As the red color decreases, the emission intensity and chromaticity vary and change. The temperature change that occurs in the light-emitting diode may be due to fluctuations in the ambient temperature, but from the light-emitting diode and the driving IC. It was found that the greatest amount was due to fever.

  Then, the present inventor, in a light-emitting element including a plurality of light-emitting diodes, performs temperature compensation on a light-emitting diode having the largest change in light emission intensity at least with respect to a temperature change, for example, a red light-emitting diode. The inventors have found that variations in light emission intensity and chromaticity due to temperature changes of the light emitting diode can be reduced, and that variations in light emission intensity and chromaticity of the light emitting element can be reduced, and the present invention has been completed.

  That is, the present invention eliminates the complexity of color control and circuit configuration in a multi-chip light emitting element, and can perform emission control of multicolor light and white light with higher accuracy than the conventional example by a simple driving method. In addition, the variation in white chromaticity obtained from the light emitting diodes of the three primary colors R, G, and B can be easily and accurately controlled from the outside, and the temperature rise of the light emitting element can be achieved. Another object of the present invention is to provide a light-emitting element with little change in emission intensity and chromaticity even when the ambient temperature changes.

  Another object of the present invention is that in white light emission by the three primary colors R, G, and B, there is a discontinuous region between the emission spectra of R and G, and the white color is incomplete. An object of the present invention is to provide a light emitting element capable of continuous white light emission from blue to blue.

  The above object of the present invention can be achieved by the following configurations. That is, the invention of the light-emitting element according to claim 1 is a light-emitting element in which a plurality of light-emitting diodes and a driving IC that drives these light-emitting diodes are integrated, and the driving IC changes light output due to temperature change. A temperature compensation circuit for compensating for the above is incorporated.

  According to a second aspect of the present invention, in the light emitting device according to the first aspect, the driving IC has one type of temperature compensation circuit, and the light output changes most with respect to the temperature among the plurality of light emitting diodes. It is characterized in that temperature compensation is performed for the light emitting diode.

  According to a third aspect of the present invention, in the light emitting device according to the second aspect, the light emitting diode that performs the temperature compensation is a red light emitting diode.

  According to a fourth aspect of the present invention, in the light emitting device according to the first aspect, the driving IC has two types of temperature compensation circuits, and a plurality of light emitting diodes having three or more types of light emission wavelengths (light emission colors). Among them, one temperature compensation circuit performs temperature compensation on a light emitting diode having a light emission wavelength (light emission color) having the largest change in light output with respect to temperature, and the other temperature compensation circuit performs all other light emission wavelengths (light emission). The temperature compensation is commonly performed for the light emitting diodes of the color).

  According to a fifth aspect of the present invention, in the light emitting device according to the first aspect, the driving IC includes a temperature compensation circuit for each light emission wavelength (light emission color) of the plurality of light emitting diodes, and for all the light emitting diodes. It is characterized in that temperature compensation is performed.

  The invention according to claim 6 is the light emitting device according to any one of claims 1 to 5, wherein the driving IC has a current value for each of the plurality of light emitting diodes or a current ratio between the plurality of light emitting diodes. It has a function of fine adjustment.

  The invention of claim 7 is characterized in that, in the light emitting device according to any one of claims 1 to 6, the plurality of light emitting diodes have a light emitting color capable of emitting white light by color mixture of the light. To do.

  According to an eighth aspect of the present invention, in the light emitting device according to the seventh aspect, the plurality of light emitting diodes include three primary colors of red, green, and blue.

  The invention according to claim 9 is the light emitting device according to claim 8, wherein the plurality of light emitting diodes further include orange and yellow, and can emit white light with a continuous emission spectrum from blue to red. To do.

  According to a tenth aspect of the present invention, in the light emitting device according to any one of the first to sixth aspects, the driving IC includes at least a current supply circuit, a plurality of bit drivers, a signal control circuit, and a correction memory. Features. In this case, a nonvolatile memory is particularly preferably used as the correction memory.

  An eleventh aspect of the present invention is the light emitting element according to any one of the first to tenth aspects, wherein the plurality of light emitting diodes are provided on a surface of the driving IC.

  According to a twelfth aspect of the present invention, in the light emitting device according to any one of the first to eleventh aspects, the plurality of light emitting diodes and the driving IC are covered with the same resin.

  By providing the above configuration, the present invention has the following excellent effects. That is, according to the first aspect of the present invention, since the driving IC for controlling the plurality of light emitting diodes is integrated with the plurality of light emitting diodes, the current value supplied to each light emitting diode by the driving IC is set. Therefore, it is possible to easily obtain a light-emitting element having uniform chromaticity accuracy and uniform quality without performing complicated current control outside the light-emitting element. In addition, although the temperature of the light emitting element varies depending on the ambient temperature, the light emission color, the nature of the driving signal, and the like, since the driving IC has a configuration for temperature compensation, Chromaticity characteristics are stabilized.

  According to the invention of claim 2, the light emission intensity and chromaticity characteristics of the light emitting element due to temperature change are stabilized only by performing temperature compensation for the light emitting diode having the largest change in light output with respect to temperature among the plurality of light emitting diodes. Can be made.

  According to the invention of claim 3, since the red light emitting diode has the largest change in the light emission intensity due to the temperature change, the light emission intensity of the light emitting element due to the temperature change only by performing temperature compensation on the red light emitting diode. And the chromaticity characteristics can be stabilized.

  According to the invention of claim 4, temperature compensation is performed independently for a plurality of light emitting diodes having the largest change in light emission intensity due to a temperature change, and the temperature is separately set separately for the others. Since compensation is performed, the light emission intensity and chromaticity characteristics of the light emitting element due to temperature change can be further stabilized.

  According to the invention of claim 5, even if a plurality of light emitting diodes have similar emission intensity change characteristics due to temperature changes, the change in emission intensity due to temperature changes is not necessarily linear. In addition, the light emission wavelength (light emission color) of each light emitting diode is different, but in such a case as well, the change characteristic of the light emission intensity due to temperature change is considered for each light emission wavelength (light emission color) of each light emitting diode. Temperature compensation can be performed accurately.

  According to the invention of claim 6, it is possible to correct the variation in electro-optical characteristics between the light emitting diodes of the same color for each light emitting element, and the current flowing in each light emitting diode for obtaining light of a predetermined synthesized color. Since the value can be controlled, it is possible to obtain a light emitting element of uniform quality that can easily and accurately control the variation in light emission intensity and light emission color for each light emitting element.

  According to the invention of claim 7, the white light source is a light source required in a wide technical field such as a backlight of a liquid crystal display panel and illumination light, and can be applied to these wide technical fields. A light emitting element is obtained.

  According to the eighth aspect of the present invention, a light-emitting element that can easily emit white light with good color reproducibility when used for a backlight of a liquid crystal display panel can be obtained.

  According to the ninth aspect of the present invention, the gap between the emission spectrum of the red light emitting diode and the emission spectrum of the green light emitting diode with a wide emission spectrum interval can be supplemented by at least one of the orange light emitting diode and the yellow light emitting diode. Therefore, a light emitting element capable of obtaining white light having a substantially continuous spectral distribution from red to blue is obtained.

  Further, according to the invention of claim 10, since the current value supplied to each light emitting diode can be controlled by a driving IC having a simple configuration, the color can be easily adjusted without performing complicated current control outside the light emitting element. A light emitting element with high accuracy and uniform quality can be obtained. In this case, especially if a non-volatile memory is used as the memory, the stored data will not be lost even if the power is turned off. Therefore, once the correction data is stored in the non-volatile memory, the power is turned off again after the power is turned off. It is not necessary to store the correction data again even when the is input.

  According to the invention of claim 11, the driving IC itself can be used as a substrate for fixing a plurality of light emitting diodes, and wire bonding between the driving IC and the plurality of light emitting diodes is small. Therefore, a small light emitting element can be obtained. Further, since the temperature difference between the driving IC and the plurality of light emitting diodes is reduced, temperature compensation with higher accuracy is possible.

  Furthermore, according to the invention of claim 12, since the plurality of light emitting diodes and the driving IC are covered and integrated with the same resin, a light emitting element with good assembling workability can be obtained.

  Embodiments of the present invention will be described below with reference to the drawings. However, the following embodiments are examples for explaining a light emitting element including light emitting diodes of three primary colors of R, G, and B for embodying the technical idea of the present invention. However, in the present invention, in addition to the three primary colors of R, G, and B, for example, in the case of a light emitting element combined with a light emitting diode capable of emitting at least one of O and Y, or a plurality of other colors capable of emitting other colors. The present invention is equally applicable to a light-emitting element including a light-emitting diode or a light-emitting element having a plurality of sets of light-emitting diodes of the three primary colors R, G, and B.

  The light-emitting element 1 of Example 1 will be described with reference to FIGS. FIG. 1 is an equivalent circuit diagram showing a driving IC for the light emitting device of the first embodiment in a block diagram, FIG. 2 is a modification of the light emitting device of the first embodiment, and FIG. 3 is a light emission of the first embodiment. FIG. 4 is a diagram showing a specific example of the internal circuit of the driving IC for the light emitting element of FIG. 3.

  FIG. 5 is a plan view showing a light emitting element in which a chip-type light emitting diode and a driving IC are mounted on the molding frame of the first embodiment through a mold resin, and FIG. 6 is a driving IC of the first embodiment. FIG. 7 is a plan view showing a light-emitting element mounted on a molding frame with each light-emitting diode mounted on the mold resin, and FIG. 7 is a diagram illustrating the mounting of each light-emitting diode on the driving IC of Example 1. It is the perspective view which represented the light emitting element through the mold resin. 1 to 7, the same reference numerals are given to the same components as those of the prior invention, and a part of the description will be omitted.

  In the light-emitting element 1 according to the first embodiment, a driving IC 3 and a light-emitting circuit including light-emitting diodes 2R, 2G, and 2B connected thereto are connected between two external terminals 5 and 6, and external terminals 7CR, 7CG, and 7CB. The light emission intensity and chromaticity of each of the light emitting diodes 2R, 2G, and 2B are controlled by the control signal from the drive IC 3, and the driving IC 3 includes a current supply circuit 11, a correction circuit 17, various signal control circuits 18, and It is the same as the driving IC 3A for the light emitting element 10A of the prior application in that the multi-bit driver 19 is provided, but for driving the light emitting element 10A of the prior application in that it is further provided with a temperature compensation circuit 20. It is different from IC3A.

  The temperature compensation circuit 20 is a circuit that controls the current supply circuit 11 so as to supply a compensation current corresponding to the operating temperature of each of the light emitting diodes 2R, 2G, and 2B, and is exemplified in Patent Documents 2 to 3, for example. As is well known. In the case of the light-emitting element 1, each of the current supply circuit 11 and the temperature compensation circuit 20 is provided so that a predetermined temperature-compensated current can be supplied to each of the light-emitting diodes 2R, 2G, and 2B. .

  In this case, the change in the light emission intensity due to the temperature change of the light emitting diode, as is clear from the description of FIG. 27, is the largest for the red light emitting diode and changes at a rate of change of about 2.4% / ° C. If the current value supplied at a rate of change of about 2.4% / ° C. with respect to at least the red light emitting diode 2R is changed, the light emission intensity change of the light emitting element 1 is reduced.

  Further, as apparent from the description of FIG. 27, the change in the emission intensity due to the temperature change of the green light emitting diode and the blue light emitting diode is smaller than that of the red light emitting diode, and is about 0.4% / ° C. In addition, since they have similar characteristics, the same temperature compensation can be performed for both the green light emitting diode and the blue light emitting diode. The light-emitting element 1 ′ in this case includes two current supply circuits 11-1 and 11-2 and two temperature compensation circuits 12-1 and 12-2 as shown in FIG. The temperature compensation circuit 11-1 and the temperature compensation circuit 20-1 perform temperature compensation on the red light emitting diode 2R via the driver 19R, and the other current supply circuit 11-2 and temperature compensation circuit 20-2. Thus, the temperature compensation may be performed simultaneously on the green light emitting diode 2G and the blue light emitting diode 2B via the drivers 19G and 19B.

  On the other hand, even if the changes in the emission intensity due to the temperature change of the green light emitting diode and the blue light emitting diode are similar to each other, as is clear from the relative light intensity-forward current curve shown in FIG. The blue light emitting diodes have distinctly different relative light intensity-forward current curves. Therefore, in order to perform accurate temperature compensation for the green light emitting diode and the blue light emitting diode, it is preferable to perform temperature compensation separately for both.

  The driving IC 3 ″ for the light emitting element 1 ″ in this case includes three current supply circuits 11-1 to 11-3 and three temperature compensation circuits 12-1 to 12-3, as shown in FIG. The current supply circuit 11-1 and the temperature compensation circuit 20-1 perform temperature compensation at a rate of about 2.4% / ° C. with respect to the red light emitting diode 2R via the driver 19R. When used at a forward current of about 10 mA with respect to the green light emitting diode 2G via the driver 19G by the temperature compensation circuit 20-2, it is about 0.5% / ° C., which is stronger than about 0.4% / ° C. Temperature compensation is performed, and when the forward current is used at about 40 mA, stronger temperature compensation, for example, about 1% / ° C. is performed. Further, the current supply circuit 11-3 and the temperature compensation circuit 20-3 Blue light emitting diode via driver 19B It may raise, configured to perform temperature compensation stronger about 0.5% with respect to diode 2B.

  A specific circuit configuration of the control IC 3 ″ of the light emitting element 1 ″ is as shown in FIG. That is, the correction circuit 17 stores, for example, 3 bits, that is, 8 levels of correction levels, using, for example, a 3 × 3 bit nonvolatile memory, and outputs various signals corresponding to the selected correction level. A predetermined corrected current is supplied to each of the light emitting diodes 2R, 2G, 2B through the control circuit 18 and sent to the driver 19. Although the correction level for 3 bits is stored here, the correction level for 2 bits or 4 bits or more may be stored depending on the characteristics of the light emitting diode.

  The various signal control circuits 18 include three signal control circuits 18R, 18G, and 18B corresponding to the respective light emitting diodes 2R, 2G, and 2B. The driver 19 includes three drivers 19R, 19G, and 19B corresponding to the light emitting diodes 2R, 2G, and 2B, respectively.

Among these, taking the signal control circuit 18G and a driver 19G green emitting diodes 2G driving example, two waveform shaping circuit 18G ₁ the inversion circuit connected in series, output and the external input terminal of the correction circuit 17 7CG The AND circuits 18G _{2 to} 18G ₄ take AND outputs with the drive signals from the drivers 19G. Each output is input to the corresponding driver circuits 19G _{1 to} 19G ₄ of the driver 19G, and the respective driver circuits 19G _{1 to} 19G. The output of ₄ is connected in parallel and is supplied as a light emission current to the corresponding green light emitting diode 2G.

  The other signal control circuits 18R and 18B have the same configuration as the green signal control circuit 18G, and the other drivers 19R and 19B have the same configuration as the green driver 19G. Omitted.

  Temperature compensation circuits 12-1 to 12-3 are connected to the three current supply circuits 11-1 to 11-3, respectively, and a driver for the light emitting diode 2R whose output from the current supply circuit 11-1 is red. 19R, the output of the current supply circuit 11-2 is connected to the driver 19G for the green light emitting diode 2G, and the output of the current supply circuit 11-3 is connected to the driver 19B for the blue light emitting diode 2B. The temperature-compensated current is supplied to each of the light emitting diodes 2R, 2G, and 2B.

  The light emitting diodes 2R, 2G, and 2B are controlled to emit light by drive signals CR, CG, and CB respectively input from the external input terminals 7CR, 7CG, and 7CB. The adjustment of the light emission color of the light emitting element 1 ″ is performed by the same method as in the case of the above-mentioned prior application, and detailed description thereof will be omitted. The supplied current value is individually temperature-compensated, and the control IC 3 ″ and each of the light emitting diodes 2R, 2G, 2B are integrated as described in detail below. Since the temperature can be detected using the control IC 3 without providing a device, temperature compensation can be performed with high accuracy.

  The drive IC 3 ″ shown in FIG. 4 is configured to perform temperature compensation for each of the light emitting diodes 2R, 2G, and 2B corresponding to FIG. 3, but for driving the light emitting element 1 shown in FIG. In order to obtain IC3, one current supply circuit 11 and one temperature compensation circuit 20 are used to perform the same temperature compensation for all the light emitting diodes, or only the red light emitting diode 2R is compensated for temperature. In order to obtain the driving IC 3 ′ for the light emitting element 1 ′ shown in FIG. 2, two current supply circuits 11-1 and 11-2 and two temperature compensation circuits 12-1 and 12- 2, one current supply circuit 11-1 and the temperature compensation circuit 20-1 perform temperature compensation for the red light emitting diode 2 R, and the other current supply circuit 11-2 and the temperature compensation circuit. 20- It may be configured to perform temperature compensation simultaneously with respect to the green light emitting diode 2G and a blue light emitting diode 2B by the.

  The driving ICs 3, 3 ′, and 3 ″ of the light-emitting elements 1, 1 ′, and 1 ″ of Example 1 are different in configuration for temperature compensation, and other configurations are common, The configuration of the driving IC 3 ″ of the light emitting element 1 ″ of the first embodiment is different from the driving IC 3A of the light emitting element 10A of the prior invention only in the configurations of the current supply circuit 11 and the temperature compensation circuit 20. Other configurations are substantially the same. Therefore, the operations of the driving ICs 3, 3 'and 3 "of the light emitting elements 1, 1' and 1" of the first embodiment are both shown in the timing chart of the driving IC 3A of the prior invention shown in FIG. Thus, although detailed description thereof is omitted, according to the light-emitting elements 1, 1 ′, and 1 ″ of the first embodiment, at least temperature compensation is performed by on / off control of the drive signals CR, CG, and CB. Multi-color representation of W, R, G, B, RG, RB, GB is possible, and more than 7 colors with temperature compensation by changing the on / off time and timing of CR, CG, CB infinitely Close color expression is possible.

  As a mounting form of the light emitting element of Example 1, an example in which a chip type light emitting diode and a driving IC are mounted on a molding frame is shown in FIG. 5 as a light emitting element 1-1, and each light emitting diode is mounted on the driving IC. An example in which the driving IC is mounted on the molding frame is shown as a light emitting element 1-2 in FIG. 6, and an example in which each light emitting diode is mounted on the driving IC is shown in FIG. 7 as a light emitting element 1-3.

  The light-emitting element 1-1 shown in FIG. 5 uses a mold type having a 6-terminal molding frame as the substrate 4, and a plurality of light-emitting elements are formed on a wide molding frame 8 connected to the other external terminal 6. As the diode 2, the cathode electrodes of the three light emitting diodes 2R, 2G, and 2B having the three primary colors of red (R), green (G), and blue (B) are fixedly arranged using a conductive material. The driving IC 3-1 is also mounted to improve the heat dissipation efficiency.

  On the surface of the driving IC 3-1, output terminals 3R, 3G, and 3B for the respective light emitting diodes, driving signal input terminals 3CR, 3CG, and 3CB for the respective light emitting diodes, a power supply voltage input terminal 3V, and a common terminal 3E. , SET terminals 3SE, etc. are arranged, among these, between the output terminals 3R, 3G, 3B for the respective light emitting diodes and the respective light emitting diodes 2R, 2G, 2B, the drive signal input terminal 3CR for each light emitting diode. Between 3CG and 3CB and external terminals 7CR, 7CG and 7CB, between power supply voltage input terminal 3V and one external terminal 5, between common terminal 3E and the other external terminal 6, and SET terminal 3SE and external The terminal 7SE is electrically connected by a gold wire or the like.

  According to the light emitting element 1-1 having such a configuration, the light emitting diodes 2R, 2G, and 2B and the driving IC 3-1 are provided on the wide molded frame 8 connected to the other external terminal 6, Since the heat generated by each of the light emitting diodes 2R, 2G, and 2B and the driving IC 3-1 can be efficiently dissipated through the molding frame 8, a large current can be caused to flow through each of the light emitting diodes 2R, 2G, and 2B. Element 1-1 is obtained.

  The light-emitting element 1-2 shown in FIG. 6 uses a mold type substrate having a 6-terminal molding frame as the substrate 4, and the three primary colors of red (R) and green (G) as the plurality of light-emitting diodes 2. Three light emitting diodes 2R, 2G, 2B having a blue (B) emission color are used, and these light emitting diodes are fixedly disposed on the driving IC 3-2, and the driving IC 3-2 is disposed on the other external side. It is placed on a wide molding frame 8 connected to the terminal 6.

  The light-emitting element 1-2 includes a plurality of light-emitting diodes 2 in a chip state, and each light-emitting diode 2 includes a bare chip that is divided from a wafer, and includes a cathode electrode on the back surface. The driving IC 3-2 includes output terminals 3R, 3G, and 3B corresponding to the light emitting diodes 2R, 2G, and 2B, driving signal input terminals 3CR, 3CG, and 3CB of the light emitting diodes, one power supply terminal 3V, and the other Power source terminal 3E, and between these light emitting diode output terminals 3R, 3G, 3B and the respective light emitting diodes 2R, 2G, 2B, drive signal input terminals 3CR, 3CG, Between 3CB and external terminals 7CR, 7CG, 7CB, between power supply voltage input terminal 3V and one external terminal 5, between common terminal 3E and the other external terminal 6, and between SET terminal 3SE and external terminal 7SE Are electrically connected to each other by a gold wire or the like. The cathode side of each light emitting diode 2R, 2G, 2B is electrically connected to the other power supply terminal 3E on the surface of the driving IC 3-2 or by an internal circuit. Since the driving IC 3-2 is also mounted on a wide molded frame, the light emitting elements 1-2 are also efficiently heated by the light emitting diodes 2 R, 2 G, and 2 B and the driving IC 3-2 through the molded frame 8. Since heat can be dissipated well, a large current can be passed through each of the light emitting diodes 2R, 2G, 2B, and a bright light emitting element 1-2 is obtained.

  Here, the anode side of 2R, 2G, and 2B is connected by a gold wire or the like, but the anode side and the cathode side are electrically connected to the surface of the driving IC 3-2 by using gold bumps, solder bumps (flip chip mounting). )

  7 is integrated with a plurality of light emitting diodes 2 in a chip state on a driving IC 3-3 which also serves as a circuit board for driving these light emitting diodes in order to make a small light emitting element. It is structured. Each light emitting diode 2 is constituted by a bare chip that is divided from the wafer, and has a cathode electrode on the back surface. The driving IC 3-3 includes output terminals 3R, 3G, and 3B corresponding to the respective light emitting diodes 2R, 2G, and 2B, driving signal input terminals 3CR, 3CG, and 3CB for the respective light emitting diodes, and one power supply terminal. The external terminal 5 that functions as the external power source terminal 6 and the external terminal 6 that functions as the other power supply terminal are provided on the lower surface and part of the side surface of the driving IC 3-3 in a state of being electrically insulated. A cathode electrode side of each of the light emitting diodes 2R, 2G, and 2B is fixedly disposed using a conductive material, and a plurality of terminals such as output terminals 3R, 3G, and 3B for the light emitting diodes 2R, 2G, and 2B and the respective light emitting diodes 2R. 2G and 2B are electrically connected by a wire such as a gold wire.

  The plurality of light emitting diodes 2R, 2G, and 2B used here are those having a cathode electrode on the back surface, and are fixed to the external terminal 6 with a conductive material, but the plurality of light emitting diodes 2R, If 2G and 2B have both anode and cathode electrodes on their surfaces, either wire these two electrodes, or conductive connection (flip chip mounting) to the surface of the driving IC 3-3. Also good.

  In the light emitting element 1-3, these light emitting diodes 2R, 2G, and 2B are fixed to the surface of the driving IC 3-3, and after wiring, these surfaces are covered with a light transmissive molding resin 9. However, a very small chip-type light emitting element can be obtained.

  When the light-emitting elements 1, 1 ′, and 1 ″ of the first embodiment supply the driving signals CR, CG, and CB of the light-emitting diodes 2R, 2G, and 2B to the external input terminals 7CR, 7CG, and 7CB, the desired light-emitting intensity and color are obtained. However, as the drive signal CR, CG, CB generation circuit, a circuit using a shift register or a counter can be used.

  Therefore, a light emitting device 1-4 of Example 2 using a device having a shift register in the driving IC 3-4 was manufactured. FIG. 8 shows an equivalent circuit diagram representing the driving IC 3-4 of the light emitting element 1-4 of the second embodiment in a block diagram, and FIG. 9 shows a specific example of the internal circuit of the driving IC 3-4. 8 and 9, the same reference numerals are given to the same components as those of the first embodiment and the prior invention, and a part of the description will be omitted. In the second embodiment, the temperature compensation is individually performed for each of the light emitting diodes 2R, 2G, and 2B. As in the first embodiment, the same temperature compensation is applied to all the light emitting diodes. Alternatively, the temperature compensation can be performed only for the red light emitting diode 2R, or the temperature compensation can be individually performed for the red light emitting diode 2R, and the green light emitting diode 2G and the blue light emitting diode 2B can be provided. However, the same temperature compensation can be performed.

  In order to emit white light, the light-emitting element 1-4 of Example 2 includes three light emitting diodes 2 having three primary colors of red (R), green (G), and blue (B). The light emitting diodes 2R, 2G, and 2B are used, and the driving IC 3-4 and the light emitting circuit composed of the light emitting diodes 2R, 2G, and 2B connected thereto are connected between the two external terminals 5 and 6, The CLOCK signal, the light emission input signal SI, and the LOAD signal are input to the external terminals 7CL, 7SI, and 7LO, respectively, and if necessary, the strobe signal STB is input to the 7ST, and the same light emission output as the light emission input signal SI is input from the external input terminal 7SO. The circuit configuration is such that the signal SO is output.

  The driving IC 3-4 of the second embodiment includes power supply circuits 11-1 to 11-3, temperature compensation circuits 20-1 to 20-3, a 3-bit shift register 12, a strobe (STB) control circuit 16, and 3 bits. A correction circuit 17 including a latch 17L and a non-volatile memory 17M, various signal control circuits 18, and a driver 19 are provided. Of these, the STB control circuit 16 can be omitted.

  The correction memory 17M is a 3 × 3 bit non-volatile memory that stores 3 bits, that is, 8 levels of correction levels, and outputs various signal control circuits corresponding to the selected correction level. 18 is sent to the driver 19 to supply a predetermined corrected current to each of the light emitting diodes 2R, 2G, 2B.

The various signal control circuits 18 include three signal control circuits 18R, 18G, and 18B corresponding to the respective light-emitting diodes 2R, 2G, and 2B. Each signal control circuit 18R, 18G, and 18B emits green light, for example. taking as an example the one for the diode 2G driving, two inverting circuit and the waveform shaping circuit 18G ₁ connected in series, to no output of the output and the 3-bit latch 17L from the correction memory 17M and the output of the STB control circuit 16 The AND circuits 18G _{2 to} 18G ₄ take AND outputs, and the outputs of the respective waveform shaping circuits and AND circuits 18G _{1 to} 18G ₄ are input to corresponding driver circuits 19G ₁ to 19G ₄ of the driver 19G. The outputs of the driver circuits 19G _{1 to} 19G ₄ are connected in parallel and supplied to the corresponding green light emitting diode 2G. ing.

  The signal control circuits 18R and 18B for driving the red light emitting diode 2R and the blue light emitting diode 2B and the drivers 19R and 19B have the same configuration as the various signal control circuits 18G and driver 19G for driving the green light emitting diode 2G. Although not shown, the adjustment of the emission color of the light-emitting element 1-4 is the same as that of the light-emitting element 1 ″ of the first embodiment, and is omitted.

  Therefore, in this driving IC 3-4, signals corresponding to the driving signals CR, CG, CB of the light emitting element 1 ″ of the first embodiment are output as the output of the 3-bit latch 17L of the correction circuit 17 or the output of the STB control circuit 16. The timing chart of the operation of this driving IC 3-4 is as shown in Fig. 10 when the STB control circuit 16 is not used, and is shown in Fig. 11 when the STB control circuit 16 is used. It becomes as follows.

  First, the case where the STB control circuit 16 is not used will be described with reference to FIG. 10. In this example, as the plurality of light emitting diodes 2, three types of light emitting diodes 2R, 2G, Since 2B is used, the light emission input signal SI is equivalent to one period of three consecutive pulses of the CLOCK signal. However, after the shift register 12 separates and holds signals corresponding to R, G, and B, LOAD One pulse is required for the 3-bit latch 17L to read and hold the signal held in the shift register 12 by the signal.

  When the power supply voltage is supplied to the driving IC 3-4, the 3-bit shift register 12 synchronizes with the falling edge of the CLOCK signal applied to the external terminal 7CL from the light emission input signal SI, respectively. A signal for 3 bits corresponding to B is separated and held. The signal held by the 3-bit shift register 12 is read by the 3-bit latch 17L in synchronization with the LOAD signal, and the 3-bit latch 17L holds the read signal for the next period.

  For example, in FIG. 10, the light emission input signal SI in the first cycle is in order of signals corresponding to B, G, and R, and this light emission input signal SI is shifted by 3 bits during the first cycle. The register 12 holds R, G, and B separately and is read into the 3-bit latch 17L in synchronization with the LOAD signal. The signal held in the shift register 12 read by the 3-bit latch 17L is the second cycle. It is held as it is. Therefore, all latch outputs corresponding to R, G, and B of the 3-bit latch 17L are at the H level during the second period.

  The light emitting diodes 2R, 2G, and 2B are driven by the output of the 3-bit latch 17L based on the current supplied from the current supply circuits 11-1 to 11-3 that have been temperature compensated by the driver 19 via the signal processing circuit 18. Therefore, during the second period, all the light emitting diodes 2R, 2G, and 2B emit light, and as a result, temperature-compensated white light (W) is obtained.

  Similarly, for example, in the light emission input signal SI in the second period and the third period, only the signals corresponding to R and G are H level, respectively, so that only the red light emitting diode 2R emits light in the third period. Temperature-compensated red light is obtained, and in the fourth period, only the green light emitting diode 2G emits light to obtain temperature-compensated green light.

  In this way, when the STB control circuit 16 is not used in the light emitting element 1-4 of the second embodiment, based on the combination of R, G, and B components included in one cycle of the light emission input signal SI. Since the combined color can be emitted during the next period, at least seven colors of W, R, G, B, RG, RB and GB can be temperature compensated.

  Next, a case where the STB control circuit 16 is used will be described. The operation of the driving IC 3-4 for the light emitting element 1-4 including the STB control circuit 16 is as shown in the timing chart of FIG. That is, when the power supply voltage is supplied to the driving IC 3-4, the 3-bit shift register 12 synchronizes with the falling edge of the CLOCK signal applied to the external terminal 7CL, respectively, from the light emission input signal SI to R, The 3-bit signals corresponding to G and B are separated and held, and the signal held by the 3-bit shift register 12 is read by the 3-bit latch 17L in synchronization with the LOAD signal, and the 3-bit latch 17L reads this signal. Hold the signal for the next period.

  However, when the STB control circuit 16 is not used, the signal held by the 3-bit latch 17L is supplied to the driver 19 through the signal processing circuit 18 as it is for one period, but the STB control circuit 16 Is used, an AND output of the signal held in the 3-bit latch 17L by the STB control circuit 16 and the strobe signal STB input from the external terminal 7ST is supplied to the driver 19 via the signal processing circuit 18. ing. Therefore, when the STB control circuit 16 is used, a signal supplied to the driver 19 through the signal processing circuit 18 during one cycle can be controlled by the strobe signal STB.

  For example, in FIG. 11, the light emission input signal SI in the first cycle is sequentially H-level corresponding to B, G, and R, and this light emission input signal SI is shifted by 3 bits during the first cycle. The signal held by the register 12 is read into the 3-bit latch 17L in synchronization with the LOAD signal, and the signal held by the shift register 12 read by the 3-bit latch 17L is held as it is for the second period. The 3-bit latch 17L The latch outputs corresponding to each of R, G, and B are all at the H level.

  However, the output of the 3-bit latch 17L is ANDed with the strobe signal STB in the STB control circuit 16 and is subjected to temperature compensation by the driver 19 via the signal processing circuit 18 and current supply circuits 11-1 to 11-3. Since each light emitting diode 2R, 2G, 2B is driven based on the supplied current, each light emitting diode 2R, 2G, 2B emits light in synchronization with the strobe signal STB during the second period, In this case, all the light is emitted in two times corresponding to the strobe signal STB, and as a result, temperature-compensated white light (W) blinking twice during the second period is obtained.

  Similarly, for example, the light emission input signal S1 in the second period and the third period is H level only for the signals corresponding to R and G, respectively, so that the third period corresponds to the strobe signal STB in the third period. Thus, temperature-compensated red light is obtained in which only the red light emitting diode 2R emits light for a time shorter than the period of one cycle. In the fourth cycle, only the green light emitting diode 2G corresponds to the strobe signal STB of the fourth cycle. A temperature-compensated green light that emits light for a time shorter than one period is obtained.

  As described above, when the STB control circuit 16 is used in the light emitting element 1-4, the light emitting time of each of the light emitting diodes 2R, 2G, and 2B in each period can be changed. 2B can change the gradations of the respective emission colors, and apparently multicolored light with temperature compensation can be obtained.

  In the light emitting element 1-4 of Example 2, the same light emission output signal SO as the light emission input signal SI is output from the external input terminal 7SO. Therefore, the light emission output signal SO is used as an external input terminal of another light emitting element. By inputting 7SO, a plurality of N light emitting elements can be connected in cascade to control light emission collectively. In this case, the number of data between the LOAD data may be 3 × N.

  Further, as a mounting form of the light emitting element of Example 2, an example in which a chip type light emitting diode is mounted on a molding frame is shown in FIG. 12 as a light emitting element 1-5, and each light emitting diode is mounted on a driving IC. Is shown as a light-emitting element 1-6 in FIG. FIG. 12 is a plan view showing a light emitting element 1-5 in which a chip-type light emitting diode is mounted on a molding frame through a light-transmitting mold resin. FIG. 13 shows each light emitting diode on a driving IC. 1 is a perspective view showing a light-emitting element 1-6 mounted with a mold resin, and the same components as those of the light-emitting elements 1-1 to 1-3 of Example 1 are denoted by the same reference numerals. is there.

  The light emitting element 1-5 of the second embodiment is greatly different from the light emitting element 1-1 of the first embodiment in that the driving IC 3-5 has output terminals 3R, 3G, 3B for the respective light emitting diodes. In addition to the power supply voltage input terminal 3V and the common terminal 3E, a CLOCK signal input terminal 3CL, a light emission signal input terminal 3SI, a LOAD signal input terminal 3LO, and a light emission signal output terminal 3SO are provided, and one external terminal 5 is provided as an external terminal. In addition to the other external terminal 6, an external clock input terminal 7CL, an external light emission signal input terminal 7SI, an external LOAD signal input terminal 7LO, and an external light emission signal output terminal 7SO are provided, and each terminal of the driving IC 3-5 And the connection relationship between each of the light emitting diodes 2R, 2G, and 2B and the connection relationship with each external terminal are the same as those described in the first embodiment. Description thereof is omitted. In this case, a strobe terminal STB or a reset terminal SE can be provided as necessary.

  Further, the light-emitting element 1-6, which is an example in which each light-emitting diode is mounted on the driving IC of Example 2, is largely different from the light-emitting element 1-3 of Example 1 shown in FIG. In the light emitting element 1-3 of FIG. 1, the drive signal input terminals are 3CR, 3CG, and 3CB, whereas in the light emitting element 1-6 of the second embodiment, the CLOCK signal input terminal 3CL, the light emission signal input terminal 3SI, and the LOAD signal input terminal are used. 3LO and the drive signal output terminal 3SO, and the other configuration is the same as that of the light-emitting element 1-3 of the first embodiment, and thus detailed description thereof is omitted.

  As the light emitting device 1-7 of Example 3, a device using a counter circuit in the driving IC 3-7 was manufactured. FIG. 14 is an equivalent circuit diagram representing the driving IC 3-7 of the light emitting element 1-7 of the third embodiment in a block diagram, FIG. 15 is a specific example of the internal circuit of the driving IC 3-7, FIG. 16 shows a timing chart for explaining the operation of the driving IC 3-7. 14 and 15, the same reference numerals are given to the same components as those in Embodiments 1 and 2 and the prior invention, and a part of the description will be omitted. In the third embodiment, the temperature compensation is individually performed for each of the light emitting diodes 2R, 2G, and 2B. However, as in the first embodiment, the same temperature compensation is applied to all the light emitting diodes. Alternatively, the temperature compensation may be performed only for the red light emitting diode 2R, or the temperature compensation may be individually performed for the red light emitting diode 2R, and the green light emitting diode 2G and the blue light emitting diode 2B may be provided. However, the same temperature compensation can be performed.

  The driving IC 3-7 for the light emitting element 1-7 of the third embodiment includes power supply circuits 11-1 to 11-3, temperature compensation circuits 20-1 to 20-3, a 3-bit counter 12, and a 3 × 3 bit nonvolatile memory. A correction circuit 17 composed of a volatile memory, various signal control circuits 18 and a driver 19, of which the correction circuit 17 composed of a 3 × 3 bit non-volatile memory corresponds to 3 bits for each bit, that is, eight levels of correction levels. The output of the selected correction level is supplied with a predetermined corrected current to each of the light emitting diodes 2R, 2G, and 2B via various signal control circuits 18 and a driver 19.

The various signal control circuits 18 include three signal control circuits 18R, 18G, and 18B corresponding to the respective light-emitting diodes 2R, 2G, and 2B. Each signal control circuit 18R, 18G, and 18B emits green light, for example. taking as an example the one for the diode 2G driving, two inverting circuit and the waveform shaping circuit 18G ₁ connected in series, the output terminal of the output and the counter circuit 12 from the correction circuit 17 consisting of 3 × 3 bit non-volatile memory 12 The AND circuit 18G _{2 to} 18G ₄ takes an AND output with the output of ₂ and the output of each signal control circuit 18G is input to the corresponding driver circuits 19G _{1 to} 19G ₄ of the driver 19G. The outputs of 19G _{1 to} 19G ₄ are connected in parallel and supplied to the corresponding green light emitting diode 2G.

  The signal control circuits 18R and 18B for driving the red light emitting diode 2R and the blue light emitting diode 2B and the drivers 19R and 19B have the same configuration as the signal control circuit 18G and driver 19G for driving the green light emitting diode 2G. However, the illustration is omitted, and the adjustment of the emission color of the light emitting element 1-4 is the same as in the case of the light emitting element 1 ″ of the first embodiment, and is omitted.

Therefore, in this driving IC 3-7, signals corresponding to the driving signals CR, CG, CB of the light emitting element 1 ″ of the first embodiment are obtained as outputs of the output terminals 12 ₁ , 12 ₂ , 12 ₃ of the counter circuit 12. It is done.

The operation of the driving IC 3-7 of the light-emitting element 1-7 of Example 3 is as shown in the timing chart of FIG. That is, when the power supply voltage is supplied to the driving IC 3-7, when the pulsed control signal CRGB is input to the external terminal 7, the output terminal 12 of the 3-bit counter circuit 12 is synchronized with the rising edge of the pulse. _1-12 output to one terminal of the _three appears, the output of the terminal in synchronization with the falling of the pulse is lost. When the next pulse is input to the external terminal 7, an output appears at the next terminal different from the output terminal selected first. In other words, 3-bit counter circuit 12, each time a pulse is inputted to the external terminal 7 is selected one of the output terminals 12 ₁ to 12 _3, the signal processing circuit by an output of the output terminal 12 ₁ to 12 ₃ 18 Then, one of the light emitting diodes 2R, 2G, and 2B emits light based on the current supplied from the current supply circuits 11-1 to 11-3 that have been temperature compensated by the driver 19, and the output terminals 12 _{1 to} 12 ₃ When neither is selected, all of the light emitting diodes 2R, 2G, and 2B emit light. Therefore, the light-emitting element 1-7 of Example 3 can also emit light with temperature compensation.

  In this case, in the light emitting element 1-7, one cycle is composed of three pulses, and each of the light emitting diodes 2R, 2G, and 2B emits light in order during the one cycle. Therefore, as shown in FIG. 16, when the widths of three consecutive pulses within one cycle are all equal as the control signal CRGB (for example, in the case of the region a), each of the light emitting diodes 2R, 2G, 2B Since the light emission times are equal, if the light emission interval is determined in consideration of the afterimage time of the human eye, the emission color visible to the human eye is white. When the widths of three consecutive pulses are different as the control signal CRGB (for example, in the case of the region b), the light emission times of the light-emitting diodes 2R, 2G, and 2B are the pulse widths of the corresponding control signal CRGB. Therefore, the luminescent color visible to the human eye is a color in which a color having a long luminescent time is emphasized.

  In addition, since each of the light emitting diodes 2R, 2G, and 2B emits light in a predetermined order, for example, when obtaining red light, the pulse width corresponding to the red light emitting diode 2R in the control signal CRGB is maximized in one cycle. The pulse widths corresponding to the green light emitting diode 2G and the blue light emitting diode 2B may be made the smallest within the range in which the 3-bit counter 12 can respond. In the light emitting element 1-7 of the third embodiment, a SET terminal for resetting the 3-bit counter 12 may be provided as necessary.

  As described above, in the light-emitting element 1-7 of Example 3, the width of each of the three consecutive pulses as the control signal CRGB is changed according to the required emission color, thereby substantially changing from red to blue. Stepless temperature-compensated color can be developed, and in the case of white light, red, green, and blue light-emitting components can be obtained and temperature-compensated white light with high chromaticity accuracy can be obtained. .

  Since the light-emitting element of Example 3 requires only one CRGB input voltage, it includes a three-terminal type (one-way type) including an external terminal 5 that functions as one power supply terminal and an external terminal 6 that functions as the other power supply terminal. Including a power supply terminal having two terminals). Examples of mounting the light-emitting element of Example 3 are shown in FIGS.

  FIG. 17 is a plan view of the light-emitting element 1-8 in which each chip-type light-emitting diode 2 and the driving IC are mounted on the molding frame 8 of Example 3 as seen through the mold resin. FIG. FIG. 19 is a perspective view of a light-emitting element 1-9 mounted with a driving IC having a SET terminal used for switching between a lighting mode and a correction data storage mode as seen through a mold resin. FIG. 19 shows each light emission on the driving IC. FIG. 20 is a perspective view showing a light emitting element 1-10 mounted with a diode through a mold resin. FIG. 20 fixes each light emitting diode 2R, 2G, 2B on the driving IC 3-11 and this driving IC 3 21 is a plan view (FIG. 20 (a)) and a side view (FIG. 20 (b)) of the lamp-type light emitting element 1-11 in which −11 is fixed on the terminal 6 as seen through, and FIG. FIG. 21A is a plan view (FIG. 21A) and a side view (see FIG. 21A) of a mold resin of a lamp-type light emitting element 1-12 in which the driving IC 3-12 and the light emitting diodes 2R, 2G, and 2B are respectively fixed on the terminals 6. FIG. 21 (b)).

  Also, in these three-terminal type light emitting elements, reset terminals 7SE to 3SE can be provided in order to store a predetermined correction value for the correction memory of each driving IC. In this case, FIG. It will be at least a 4-terminal type as shown. The specific configuration of each of the mounting examples in FIGS. 17 to 22 is recognized by those skilled in the art from the description of the above-described embodiments, and thus detailed description thereof will be omitted.

FIG. 3 is an equivalent circuit diagram illustrating, in a block diagram, a driving IC for the light emitting element according to the first embodiment. 6 is a modification of the light emitting element of Example 1. . FIG. 6 is still another modification of the light-emitting element of Example 1. FIG. FIG. 4 is a diagram illustrating a specific example of an internal circuit of the driving IC in FIG. 3 according to the first embodiment. 3 is a plan view of a light emitting device in which a chip-type light emitting diode and a driving IC are mounted on the molding frame of Example 1. FIG. FIG. 3 is a plan view of a light emitting element in which each light emitting diode is mounted on the driving IC of Example 1 and mounted on a molding frame. FIG. 3 is a perspective view of an example in which each light emitting diode is mounted on the driving IC according to the first embodiment. FIG. 6 is an equivalent circuit diagram illustrating, in a block diagram, a driving IC for a light-emitting element according to Example 2. 7 is a specific example of an internal circuit of a driving IC according to a second embodiment. 10 is a timing chart for explaining an operation when the STB control circuit of the driving IC according to the second embodiment is not used. 12 is a timing chart for explaining an operation when the STB control circuit of the driving IC according to the second embodiment is used. 6 is a plan view of a light emitting device in which a chip-type light emitting diode is mounted on a molded frame of Example 2. FIG. 6 is a perspective view of a light emitting element in which each light emitting diode is mounted on a driving IC according to Example 2. FIG. FIG. 10 is an equivalent circuit diagram illustrating the driving IC according to the third embodiment in a block diagram. 12 is a specific example of an internal circuit of a driving IC according to a third embodiment. 12 is a timing chart for explaining the operation of the driving IC according to the third embodiment. 6 is a plan view of a light emitting device in which each chip type light emitting diode and a driving IC are mounted on a molding frame of Example 3. FIG. FIG. 6 is a plan view of a light emitting element on which a driving IC having a SET terminal according to Example 3 is mounted. FIG. 6 is a perspective view of a light emitting element in which each light emitting diode is mounted on a driving IC in Example 3. A plan view (FIG. 20 (a)) and a side view (FIG. 20 (b)) of a lamp-type light emitting element in which each light emitting diode is fixed on the driving IC of Example 3 and this driving IC is fixed on a terminal. ). FIG. 21 is a plan view (FIG. 21A) and a side view (FIG. 21B) of a lamp-type light emitting element in which a driving IC and a light emitting diode of Example 3 are fixed on a terminal. It is a figure showing the light emission intensity-forward current characteristic of typical various light emitting diodes. It is a spectrum distribution characteristic view of various light emitting diodes. It is the equivalent circuit diagram which represented the internal structure of drive IC of the light emitting element of prior application invention with the block diagram. It is a figure which shows an example of the internal circuit of drive IC of prior invention. 6 is a timing chart for explaining the operation of the driving IC according to the invention of the prior application. Typically, it is a light emission intensity-ambient temperature characteristic diagram of various light emitting diodes.

Explanation of symbols

1, 1-1 to 1-12, 1A to 1C Light-emitting element 2, 2R, 2G, 2B Light-emitting diode 3, 3-1 to 3-12, 3A to 3C Driving IC
4 Circuit board 5, 6, 7CL, 7SI, 7LO, 7SO, 7ST, 7SE External terminal 7CR, 7CG, 7CB External terminal 8 Molded frame 9 Light transmissive mold resin 11, 11-1 to 11-3 Current supply circuit 12 3-bit shift register 17 correcting circuit 17L 3-bit latch 17M correction memory 18 various signal control circuit 18R, 18G, 18B signal control circuit 19,19R, 19G, 19B driver 19G ₁ ~19G ₄ driver circuit 20,20-1～20 -3 Temperature compensation circuit

Claims (12)

  A light emitting element in which a plurality of light emitting diodes and a driving IC for driving these light emitting diodes are integrated, wherein the driving IC has a built-in temperature compensation circuit that compensates for a change in light output due to a temperature change. A light emitting element.   2. The driving IC according to claim 1, wherein the driving IC has one type of temperature compensation circuit, and temperature compensation is performed on a light emitting diode having the largest change in light output with respect to temperature among a plurality of light emitting diodes. Light emitting element.   3. The light emitting device according to claim 2, wherein the light emitting diode that performs temperature compensation is a red light emitting diode.   The driving IC has two types of temperature compensation circuits, and among the plurality of light emitting diodes having three or more types of light emission wavelengths (light emission colors), the light emission having the largest change in light output with respect to temperature by one temperature compensation circuit. The temperature compensation is performed for the light emitting diode of the wavelength (light emitting color), and the temperature compensation is commonly performed for the light emitting diodes of all other light emitting wavelengths (light emitting color) by the other temperature compensation circuit. The light emitting device according to claim 1.   2. The light emitting device according to claim 1, wherein the driving IC includes a temperature compensation circuit for each light emission wavelength (light emission color) of the plurality of light emitting diodes, and performs temperature compensation for all the light emitting diodes.   The light emitting element according to claim 1, wherein the driving IC has a function of finely adjusting a current value for each of the plurality of light emitting diodes or a current ratio between the plurality of light emitting diodes. .   The light emitting device according to any one of claims 1 to 6, wherein the plurality of light emitting diodes have a light emitting color capable of emitting white light by mixing colors of the light.   The light emitting device according to claim 7, wherein the plurality of light emitting diodes include three primary colors of red, green, and blue.   The light emitting device according to claim 8, wherein the plurality of light emitting diodes further include orange and yellow, and can emit white light having a continuous light emission spectrum from blue to red.   The light emitting device according to claim 1, wherein the driving IC includes at least a current supply circuit, a multi-bit driver, a signal control circuit, and a correction memory.   The light emitting element according to claim 1, wherein the plurality of light emitting diodes are provided on a surface of the driving IC.   The light emitting device according to claim 1, wherein the plurality of light emitting diodes and the driving IC are covered with the same resin.

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