JP6481246B2 - Light emitting device control circuit and light emitting device - Google Patents

Description

  BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light emitting device control circuit and a light emitting device using the same, and more specifically, a light emitting device control circuit capable of adjusting a light output and a light emission color according to an input from a pulse modulation output power source. It relates to the light emitting device used.

  In recent years, semiconductor light emitting devices such as light emitting diodes (LEDs), organic EL, and inorganic EL have been developed, and since they have high luminous efficiency and long life, they are widely used in applications such as lighting and display devices.

  On the other hand, there is a need to change the emission color depending on the application, such as lighting and display devices. For example, in lighting, the emission color of lighting can be changed according to the time zone and the scene of morning and night, and in display devices. Is required to display necessary information on an indicator or a display by switching emission colors such as red, blue, and green or multicolor emission.

  Since semiconductor light emitting elements generally exhibit a substantially constant emission color with respect to input power, for example, when adjusting the emission color in a light emitting device using LEDs, it is usually necessary to individually drive and control LEDs that emit different emission colors. is there. The same applies to other semiconductor light emitting elements.

  In order to individually drive and control LEDs that emit different emission colors, the amount of current to each LED is set by a control signal from the outside that is different from the power input, and the amount of current is controlled by a circuit in the light emitting device. However, it is generally known that the wiring becomes complicated, and the cost becomes high because the system becomes complicated including a system for inputting an external signal for designating emission color and brightness and a circuit configuration for processing the external signal. There is a drawback.

  In order to solve such a problem, for example, as shown in Patent Document 1, it has an element for detecting the average magnitude of the input current, and a shunt control circuit using a transistor, a high-speed switch, or the like, A light emitting device has also been proposed in which an input current is shunted to two LED groups having different emission colors connected in parallel, and the emission color of the light emitting device is changed as a function of the magnitude of the input current. According to such a proposal, an emission color change can be realized only by an input from the power input terminal without the need for an external signal. For example, similarly to the emission color change of an incandescent bulb or a halogen lamp during dimming, It is possible to provide an LED light-emitting device having a behavior in which the color temperature of white light emitted in response to a decrease in input power is lowered and yellowishness and redness are further increased.

  In addition, a light emitting device in which the emission color changes depending on the magnitude of the input current from the variable constant current power supply has been already proposed without having an input current detection element or a complicated circuit for shunting. For example, in the light emitting device disclosed in Patent Document 2, a resistor is connected in series to one of two LED groups having different emission colors connected in parallel, and the balance of the current flowing through each LED group according to the magnitude of the input current. The emission color can be adjusted only by the input from the power input terminal without requiring an external signal.

Japanese Patent No. 5762555 Japanese Patent No. 5807195

  However, in the light emitting device according to the prior art, since the light output and the light emitting color of the light emitting device are determined according to the magnitude of the input current, the brightness can be arbitrarily set by setting different light emitting colors with the same brightness or with different light emitting colors. It cannot be set.

  In addition, since the light emitting device according to the prior art is controlled by the magnitude of the input current, for example, for pulse dimming by a constant voltage input, the input power is detected by converting the current to the magnitude of the current. It is not possible to change the color.

  On the other hand, the method of individually driving and controlling the LEDs emitting different light emission colors for arbitrarily adjusting the light output and the light emission color requires not only a complicated device but also increases the cost. External signal lines other than the input are required, which is troublesome for the installer who installs the light emitting device.

  The present invention has been made in view of the above-mentioned problems, and the object of the present invention is to adjust the light output and light emission color of the light emitting device only by pulse power input, and corresponds to constant voltage power input. It is an object of the present invention to provide a control circuit that is simple and can be reduced in size, and a light-emitting device using the control circuit.

  In order to achieve the above object, a control circuit of the present invention includes a signal generation circuit that is electrically connected to a pulse power source serving as a power supply source for a plurality of light source circuits having a light emitting unit, at least one light source circuit, and an electric circuit. The signal generation circuit includes a first resistor and a capacitor in series, the capacitor includes a bypass circuit including a second resistor, the switching circuit includes a switching element, and the signal generation circuit includes: The control signal is an on signal or an off signal of the switching circuit according to the waveform of the pulse power source.

  The on signal of the control signal is a signal that turns on the switching circuit, and the off signal of the control signal is a signal that turns off the switching circuit. When the switching circuit is turned on or off by a control signal from the signal generation circuit, current flows or is cut off in the light source circuit connected to the switching circuit, and the light output and light emission color of the entire light emitting device can be adjusted. Become.

  Note that the control signal is, for example, a potential at a certain point in the signal generation circuit, and fluctuates with a time change in a charging state of a capacitor provided in the signal generation circuit by pulse power input from the pulse power source.

  In one embodiment of the control circuit of the present invention, there are a plurality of switching circuits that are electrically connected to the light source circuit, and pulse power that provides a combination of control signals that turns on only one switching circuit and turns off the other switching circuit. A source waveform is present for each switching circuit.

  By performing on / off control of each switching circuit, energization to each light source circuit connected to the switching circuit can be controlled. Further, since only one switching circuit can be turned on, the light emitting device can selectively emit light from a specific light source circuit.

  In one aspect of the control circuit of the present invention, the signal generation circuit includes an auxiliary switching element in parallel with the capacitor, the auxiliary switching element includes at least one of an auxiliary capacitor and an auxiliary resistor in series, and the auxiliary switching element is a pulse power source. ON / OFF according to the waveform of

  In one embodiment of the control circuit of the present invention, the switching circuit includes a storage capacitor, and a current flowing from the light source circuit to the switching circuit is controlled based on a voltage stored in the storage capacitor.

  An illumination device according to the present invention includes a plurality of light source circuits having a light emitting unit, and a light emission color from a light emitting unit on at least one light source circuit is different from a light emission color from a light emitting unit on another light source circuit. The above control circuit is provided.

  The pulse power source used in the light emitting device of the present invention may be a pulse output power supply, or a power pulse conversion module or a power pulse conversion circuit that converts a constant output into a pulse output. It is preferable that power is supplied to a plurality of light source circuits having a light emitting unit and a control circuit by one pulse power source. The power pulsing circuit may be integrated with the control circuit as a module, or may be separately modularized.

  Pulse output is an output method in which output is turned on and off at high speed, and the waveform of pulse output is determined by amplitude, frequency, duty ratio, pulse shape, and the like. The duty ratio is the ratio of the output on period to the on / off period. For light-emitting devices, it is often used for dimming applications. In particular, since the pulse output is generally constant current output or constant voltage output, more accurate control of the output value is possible. In general, the dimming method for controlling the light output can provide an accurate and wide dimming range as compared with the lower limit of the output possible range of about 10% of the rated output current value.

  The pulse output is based on a pulse width modulation (PWM) output system in which the on / off repetition period is constant and the output on period is changed, or a pulse period modulation output system in which the output on period is constant and the on / off repetition period is changed.

  The pulse power source used in the control circuit and the light emitting device of the present invention is preferably a constant voltage output, the light source circuit is supplied with power from the constant voltage source, and the control circuit is also supplied with power from the constant voltage source. Therefore, the control circuit can cope with the increase / decrease in the number of parallel connections of the light source circuits while maintaining its function.

  The light source circuit according to the present invention has a light emitting unit and emits light by power input. The light emitter in the light emitting section is preferably a semiconductor light emitting element, which can reduce power consumption as compared with a conventional light source, reduce the load on the switching element, and reduce the size of the control circuit. There may be a plurality of light emitting units on the light source circuit, and the light emitting units may be connected in series and parallel in the light source circuit in order to obtain optimum electrical and light emitting characteristics.

  It is preferable that the light emitting portions of the light source circuit connected to different switching circuits emit different emission colors. The different emission colors may be different depending on the primary colors of light such as red, green, and blue, or may be different depending on the color temperature or color rendering of white light. A single light source circuit may include a light emitting unit composed of a plurality of light emission colors.

  The plurality of light source circuits may be provided on the same substrate to form a light source module, and the light emitting units of the plurality of light source circuits may be arranged in a single package.

  The light source circuit preferably has a limiting resistor for controlling the current, and the current is controlled by the number of semiconductor light emitting elements in series, the resistance value of the limiting resistor, and the like. More preferably, the total driving voltage of the semiconductor light emitting elements connected in series is close to the input voltage, so that power loss at the limiting resistor can be suppressed and the light emission efficiency of the light emitting device can be increased. Alternatively, a constant current circuit may be provided on the switching circuit in the control circuit.

  The semiconductor light emitting element generally has diode characteristics, and may be any form of element such as a light emitting diode (LED), an organic EL, and an inorganic EL. As the LED, various types of LED elements that emit a specific emission color, such as a blue LED such as InGaN and a red LED such as GaAlAs, are used. These semiconductor light-emitting elements are generally used after being packaged.

  The LED package emits light from the light emitting surface of the package through a translucent resin, etc., but there are primary color types that emit light without converting the LED element as it is, and types that convert light from the LED element with phosphors, etc. Further, as a package, there are a chip scale package type, a surface mount type, a chip on board (COB) type, and any of these may be used.

  For lighting applications, a white LED package is generally preferred in which part or all of the light from an InGaN-based LED element is converted into white light by a phosphor, so that the light emission colors from the light emitting portions on the respective light source circuits are different. The light emission color of the white LED package is appropriately selected. For display applications, primary color type LED packages that do not use phosphors are generally used.

  Since the semiconductor light emitting device is a light emitting device with excellent time response, it emits pulses in response to input on / off from the power source. However, in order to avoid flickering of light, the on / off frequency of the pulse modulated output power source is usually from 100 Hz. Is set to a high value, and more preferably 1 KHz or more, so that the human eyes do not see the pulsed light emission, and the light output is visually recognized as a time-averaged output.

  According to the present invention, the light output and light emission color of the light emitting device can be adjusted only by pulse power input, and the control circuit corresponding to the constant voltage power input is simple and can be miniaturized, and the control circuit is used. It is possible to provide a light emitting device.

It is a block diagram which shows the structure which concerns on Embodiment 1 of this invention. It is a block diagram which shows the structure which concerns on Embodiment 1 of this invention. 1 is a circuit diagram of a light emitting device and a control circuit according to Embodiment 1 of the present invention. It is a graph showing the fluctuation | variation of the signal potential Vs with respect to time for every duty ratio which concerns on Embodiment 1 of this invention. It is a graph showing the relationship between the duty ratio which concerns on Embodiment 1 of this invention, and the energization time ratio of a 2nd light source circuit. It is a graph showing the fluctuation | variation of the signal potential Vs with respect to time for every duty ratio at the time of the high frequency drive which concerns on Embodiment 1 of this invention. It is a graph showing the relationship between the duty ratio at the time of the high frequency drive which concerns on Embodiment 1 of this invention, and the energization time ratio of a 2nd light source circuit. It is a modification of the control circuit which concerns on Embodiment 1 of this invention. It is a circuit diagram of the light-emitting device and control circuit which concern on Embodiment 2 of this invention. It is a modification of the control circuit which concerns on Embodiment 2 of this invention. It is a graph showing the relationship between the duty ratio which concerns on Embodiment 2 of this invention, and the energization time ratio to a 1st light source circuit. It is a circuit diagram of the light-emitting device and control circuit which concern on Embodiment 3 of this invention. It is a circuit diagram of the light-emitting device and control circuit which concern on Embodiment 4 of this invention. It is a modification of the switching circuit which concerns on Embodiment 4 of this invention. It is a wave form diagram of the pulse power input which concerns on Embodiment 4 of this invention. It is a wiring diagram according to a display device using the light emitting device of the present invention. It is a circuit diagram of the light-emitting device and control circuit which concern on the reference form of this invention. 6 is a graph showing the relationship between the duty ratio and the amount of current flowing through the first light source circuit and the second light source circuit in Example 1. 6 is a graph showing the relationship between the relative luminous flux emitted by the light emitting device in Example 1 and the color temperature of the emitted color. 10 is a graph showing the relationship between the duty ratio and the amount of current flowing through the first light source circuit and the second light source circuit in Example 2. It is a graph showing the relationship between the duty ratio in Example 2, and the color temperature of the luminescent color which a light-emitting device emits. It is a graph showing the relationship between the duty ratio in Example 2, and the relative light beam which a light-emitting device emits. It is a graph showing the relationship between the duty ratio in Example 3, and the electric current amount which flows into each light source circuit.

  Hereinafter, the light emitting device of the present invention will be described with reference to the drawings. In the drawings of the present invention, the same reference numerals represent the same or corresponding parts. Further, in the following description, the same name and reference sign indicate the same or the same members in principle, and the detailed description will be omitted as appropriate. In addition, dimensional relationships such as length, width, thickness, and depth are changed as appropriate for clarity and simplification of the drawings, and do not represent actual dimensional relationships.

(Embodiment 1)
As shown in the block diagram of FIG. 1, the light emitting device 100 according to Embodiment 1 of the present invention is supplied with power from a constant voltage pulse modulation output power supply 10 (hereinafter referred to as pulse output power supply), and the control circuit 101 and the first The second light source circuits 11 and 12 are electrically connected to the pulse output power source 10 respectively. The power supply to the first light source circuit 11 does not necessarily have to go through the control circuit 101. A switching circuit 103 in the control circuit 101 is electrically connected in series between the second light source circuit 12 and the pulse output power supply 10, and on / off of energization is controlled by the switching circuit 103.

  The control circuit 101 includes a signal generation circuit 102 and a switching circuit 103, and the control circuit 101 outputs a control signal to the switching circuit 103 in accordance with a pulse output waveform from the pulse output power supply 10. The pulse output waveform from the pulse output power supply 10 is controlled by the input from the power supply control device 20. The power supply control device 20 controls the pulse output power supply 10 by outputting a signal such as 0-10 V or PWM by a user operation, for example. The signal from the power supply control device 20 to the pulse output power supply 10 may be a wired signal or a wireless signal.

  In response to the control signal from the signal generation circuit 102, the switching circuit 103 controls the current flowing through the second light source circuit 12, and if the switching circuit 103 cuts off the current, the light source device 100 receives the first light source circuit 11 from the light emitting device 100. If the switching circuit 103 passes current, the light emitting device 100 emits light from both the first light source circuit 11 and the second light source circuit 12.

  As shown in the block diagram of FIG. 2, the pulse circuit 104 is in the light emitting device 100, converts the electric power from the constant voltage constant output power source 30 into the pulse output, and controls the control circuit 101 and the first and second circuits. It may be a power supply source to the light source circuits 11 and 12. Further, the pulsing circuit 104 may be installed as a separate module between the constant output power source 30 and the light emitting device 100 and electrically connected thereto.

  FIG. 3 shows an example of a specific circuit diagram. The control circuit 101 is supplied with pulse power of the input potential Vin through input terminals 151 and 152 connected to a pulse output power source. Outputs to the first light source circuit 11 and the second light source circuit 12 through output terminals 153, 154, 155, and 156. Each of the first light source circuit 11 and the second light source circuit 12 includes one or more LED packages L111 to L11m and L121 to L12n as light emitting units, and the emission color and the second color from the light emitting unit of the first light source circuit. The light emission colors from the light emitting portions of the light source circuit are preferably different from each other. Since power is supplied from the constant voltage power source, the first light source circuit 11 and the second light source circuit 12 have limiting resistors R11 and R12, respectively, and the magnitude of current flowing through each light source circuit without using a regulator component. Is controlled.

  The second light source circuit 12 is connected to the switching circuit 103 including the switching element Q1 through the connection terminal 156, and the switching element Q1 controls on / off of energization to the second light source circuit 12.

  The signal generation circuit 102 for supplying a control signal to the switching circuit 103 is formed between the input terminal potentials from the power source in the control circuit 101, and the first resistor R1 and the capacitor C1 are connected in series. A bypass circuit having a second resistor R2 is connected. By forming a bypass circuit having the second resistor R2 between both ends of the capacitor C1, the capacitor C1 is discharged through the bypass circuit when the power input is turned off. With this configuration of the signal generation circuit 102, the capacitor C1 is repeatedly charged and discharged with respect to the pulse power input from the power source. Note that the signal generation circuit 102 is not necessarily connected between power supply potentials, and a potential adjusted from the power supply potential may be input thereto.

  The signal potential Vs on the high potential side of the resistor R2 is connected to the gate of the switching element Q1, and functions as a control signal for turning on the switching element Q1. The signal potential Vs varies depending on the charged state of the capacitor C1, and is 0 when the capacitor C1 is discharged. When the capacitor C1 is saturated, the signal potential Vs is caused by the first resistor R1 and the second resistor R2 of the input potential Vin. The partial pressure value is Vin × r2 / (r1 + r2). Here, r1 and r2 are resistance values of the resistors R1 and R2, respectively.

  In order for the current to flow to the light source circuit 12, a voltage exceeding the gate threshold voltage needs to be applied between the gate and source of the switching element Q1 of the switching circuit 103. If the signal potential Vs that provides a potential corresponding to the gate threshold voltage is set as the threshold potential, a current flows to the light source circuit 12 if the signal potential Vs becomes higher than the threshold potential by charging the capacitor C1. It becomes like this.

  Therefore, the resistance values of the resistors R1 and R2 are preferably set so that Vin × r2 / (r1 + r2), which is the signal potential Vs when the capacitor C1 is saturated, exceeds the threshold potential. Alternatively, even if the threshold potential of the signal potential Vs is lower than the gate threshold potential of the switching element Q1, the signal potential Vs may be amplified in the control circuit 101 so that the switching element Q1 is turned on.

  Note that the first resistor R1 and the second resistor R2 may be divided into a plurality of resistors, and the signal potential Vs may be obtained from an intermediate point of these resistors. Further, the first resistor R1 may be on either side of the polarity of the capacitor, or a desired signal potential Vs may be obtained by being divided and connected on both sides of the polarity of the capacitor.

  In FIG. 3, the current I that flows through the first resistor R1 by the input potential Vin is the sum of the current i1 that flows through the capacitor C1 and the current i2 that flows through the second resistor R2 on the bypass circuit. It is expressed by Formula 1.

  q is the charge of the capacitor C1, C is the capacitance of the capacitor C1, r1 and r2 are the resistance values of the resistors R1 and R2, and t_on is the on time of the power input. In order to simplify the calculation, the current flowing through the gate of the switching circuit 103 from the signal potential Vs is assumed to be negligibly small compared to the currents i1 and i2. In the present embodiment, the potential across the capacitor C1 is equal to the signal potential Vs.

  Assuming that the capacitor C1 is sufficiently discharged as an initial condition, the current i1 flowing through the capacitor C1, the current i2 flowing through the resistor R2, and the signal potential Vs can be solved from the above formula 1 as the following formula 2. .

  According to the above equation, the currents i1 and i2 and the signal potential Vs change according to the power input ON time t_on, and the signal potential Vs is 0 at the initial t_on = 0, but if the power input continues, the resistance R1 of the input potential Vin , R2 increases to Vin × r2 / (r1 + r2), which is a partial pressure value, as the power input on-time t_on elapses.

  The signal potential Vs rises while the pulse power input is on, but current does not flow through the second light source circuit 12 until the threshold potential for turning on the switching circuit 103 is reached, and the light emitting unit on the second light source circuit 12 Does not emit light. When the signal potential Vs exceeds the threshold potential, the switching circuit 103 is turned on and a current starts to flow through the second light source circuit 12. Thereafter, the signal potential Vs continues to rise until the power input from the pulse power source is turned off. During this time, current continues to flow through the second light source circuit 12, and the light emitting unit on the second light source circuit 12 emits light.

  When the power input from the pulse power source is turned off, no voltage is applied to the signal generation circuit 102, and the charge accumulated in the capacitor C1 is discharged through the resistor R2.

  The signal potential Vs decreases due to the discharge of the capacitor C1, and when the signal potential at the time when the pulse power input is switched from ON to OFF is Vsp, the pulse power input OFF period from that time (t_off = 0) The time change of the signal potential Vs is expressed by the following Equation 3.

  From the above equation, it can be seen that the signal potential Vs decreases with the passage of the power input off time t_off. In addition, in a periodic pulse power input with a finite off period, the signal voltage Vs is not completely zero when the pulse power input is turned on again. In particular, when the pulse power input frequency is high (the ON / OFF repetition period is short) and the duty ratio is large, the pulse power input OFF period is short, or the capacitance of the capacitor C1 and the resistance value of the second resistor R2 are low. In the case of being large, the value of the signal potential Vs at the time when the pulse power input is turned on from off is not much lowered from the signal potential Vsp at the time when the pulse power input is turned off from on.

  In the periodical pulse power input, the rise of the signal potential Vs during the on period of the pulse power input represented by Formula 2 is the same as the fall of the signal potential Vs during the off period of the pulse power input represented by Formula 3. Equilibrium is reached at the point of size. For this reason, the value of the equilibrium state of the signal potential Vs varies depending on the duty ratio and frequency of the pulse power input.

  On the contrary, in order to obtain the fluctuation characteristic of the signal potential Vs along the desired light emission change characteristic, the resistance values of the first resistor R1 and the second resistor R2 of the signal generation circuit and the capacitance of the capacitor C1 are adjusted. You can see that

  FIG. 4 shows the result of simulating the time change of the signal potential Vs due to the input of pulse power having a frequency of 1 KHz (cycle: 1000 μsec) with different duty ratios (30%, 60%, 80%) using Equations 2 and 3. In the simulation, the power supply voltage is 12 V, the resistance values of the resistors R1 and R2 are 10 KΩ and 5 KΩ, the capacitance of the capacitor C1 is 0.1 μF, and the current flowing through the switching circuit 103 is ignored. It can be seen that as the duty ratio increases, the signal potential Vs increases as a whole, including the time point (0, 1000, 2000, 3000 μsec) when the pulse power input is switched from OFF to ON.

  If the threshold potential for turning on the switching circuit 103 is set at an intermediate point where the signal potential Vs fluctuates, a period in which the signal potential Vs exceeds the threshold potential occurs because the duty ratio becomes larger than a certain value. In order for the current to flow to the second light source circuit 12 through the switching circuit 103, the pulse power input needs to be on and the signal potential Vs exceeds the threshold potential, so the second light source circuit 12 The time during which the current flows is 0 until the duty ratio reaches a certain value, and thereafter, the aspect gradually increases as the duty ratio increases.

  The ratio of the time during which the current flows through the second light source circuit 12 to the ON / OFF period of the pulse power input is set as the energization time ratio, and the simulation result of the signal potential Vs time variation shown in FIG. The ratio of the energization time to the two light source circuits 12 is graphed in FIG. In the simulation, the threshold potential is 2.4V. In the region where the duty ratio is small, current does not flow to the second light source circuit 12, current starts to flow from a certain duty ratio, and then the energization time ratio to the second light source circuit 12 increases as the duty ratio increases. I understand.

  Since a constant current flows through the second light source circuit 12 due to the limiting resistor when energized, the energization time ratio is proportional to the time average current amount to the second light source circuit 12. Therefore, the light output from the light emitting unit on the second light source circuit 12 also shows a change as shown in FIG. 5 with respect to the duty ratio.

  On the other hand, the first light source circuit 11 is electrically connected directly to the pulse output power source, and the light output from the light emitting unit of the first light source circuit 11 is proportionally correlated with the duty ratio. Therefore, the light emission from the light emitting device 100 changes the relative ratio of the light emission intensity from the light source circuit 11 and the light source circuit 12 with the change in the duty ratio of the pulse power input.

  For example, when the color temperature of the light emission color of the light emitting unit on the first light source circuit 11 is 2000K and the color temperature of the light emission color of the light emission unit on the second light source circuit 12 is 3000K, the light emitting device 100 has a duty ratio of Is small, only the light emitting part on the first light source circuit 11 emits light, and the light emission color of the light emitting device 100 is 2000K. If the duty ratio is large, the light from the light emitting part on the second light source circuit 12 is also emitted. By making a contribution, the emission color of the light emitting device 100 can be adjusted in accordance with the duty ratio of the pulse power input such that the emission color of the light emitting device 100 approaches 3000K.

  When the light is dimmed, only the light emitting part of the first light source circuit 11 emits light, and if the duty ratio increases, the light emitting parts of both the first and second light source circuits 11 and 12 emit light, so that the light output changes more greatly. However, it is preferable because dynamic light can be produced.

  Further, when the frequency of the pulse power input is increased, sufficient discharge of the charge accumulated in the capacitor is not in time for the on / off period of the pulse power input. In this embodiment, the signal potential Vs equal to the potential across the capacitor C1 is equal to the time. However, the fluctuation is small and close to a constant value. For example, if the frequency is at least twice the reciprocal of the discharge time constant, which is the product of the capacitance of the capacitor C1 and the resistance value of the second resistor R2, the charge accumulated in the capacitor C1 is 70 Even if it discharges for% time, only the initial 30% or less is discharged. Therefore, if the duty ratio is 30% or more, the fluctuation range of the signal potential Vs is within 30% of the signal potential Vsp when the pulse power input, which is the peak value, is turned off. Further, as the frequency becomes higher (the cycle becomes shorter), the fluctuation range of the signal potential Vs becomes smaller and approaches a constant value.

  In the simulation of the time variation of the signal potential Vs shown in FIG. 4, the result of simulating the time variation of the signal potential Vs for each duty ratio when only the pulse frequency of the power input is 10 times (frequency 10 KHz, period 100 μsec) is shown in FIG. Show.

  If the signal potential Vs is substantially constant as shown in FIG. 6, the signal potential Vs is close to two states of being always above or below the threshold potential with respect to the duty ratio. For this reason, the switching circuit 103 also takes a state of always on or always off depending on the duty ratio, and when the ratio of the energizing time to the second light source circuit 12 is graphed with respect to the duty ratio as in FIG. It can be seen that the energization time ratio to the light source circuit 12 changes abruptly at a certain duty ratio as shown in FIG. Further, in the duty ratio region where the switching circuit 103 is always on, the duty ratio and the ratio of the energization time to the light source circuit 12 are in a proportional relationship.

  The above shows that by changing the frequency of the pulse power input, the light emitting device 100 emits different light output and light emission color even with the same duty ratio, that is, the control circuit 101 of the light emitting device 100 of the present invention. Indicates that the light output and light emission color of the light emitting device 100 can be adjusted by the two parameters of the duty ratio and frequency of the pulse power input.

  Further, regarding the pulse shape of the power input, the light emission output and the light emission color may be adjusted not only by the square wave but also by different pulse shapes such as a triangular wave, a sine wave, and a step wave.

  Further, since the value of the signal potential Vs also changes due to the change of the input potential Vin from the pulse output power supply, the light emission change characteristic with respect to the duty ratio of the light emitting device 100 may be adjusted.

  Changes in the light output and emission color of the light-emitting device obtained by changing the waveform of the pulse power input such as the duty ratio and pulse frequency can also be obtained by changing the capacitance and resistance value of the capacitor. It is preferable to appropriately select the light control and toning characteristics.

  On the other hand, if the control circuit 1011 shown in FIG. 8 is used, it is possible to further stabilize the emission color change due to the duty ratio of the light emitting device with respect to the frequency change of the pulse power input, and the frequency of the pulse power source cannot be fixed. This is useful in practical cases.

  The signal generation circuit 1021 includes an auxiliary switching element Q2 that is on / off controlled by the pulse power waveform detection circuit 105 in parallel with the capacitor C1, and the auxiliary switching element Q2 is connected in series with the auxiliary capacitor C2 and the auxiliary resistor R3, respectively. . Only one of the auxiliary capacitor C2 and the auxiliary resistor R3 may be connected. The auxiliary capacitor C2 and the auxiliary resistor R3 have a function of assisting the signal generation circuit 1021 in generating the control signal when the auxiliary switching element Q2 is on.

  For example, when pulse power is input at a low duty ratio, the signal potential Vs rises due to charging of the capacitor C1 and the switching circuit is turned on. The auxiliary switching element Q2 is turned on, and the auxiliary capacitor C2 functions. The rise of the signal potential Vs is suppressed, and the change in emission color due to the duty ratio of the light emitting device is stabilized.

  Note that the pulse power waveform detection circuit 105 may have the same configuration as the signal generation circuit as shown in FIG. 8, and detects the pulse power input frequency using a microcomputer or the like to control the on / off of the auxiliary switching element Q2. You may do it.

(First light source circuit and second light source circuit)
Since the first light source circuit 11 and the second light source circuit 12 are configured as a single light source module, handling becomes easy. In order to facilitate the optical design of the luminaire, it is preferable that each light emission color is sufficiently mixed in the light source module, and the light emitting parts on each circuit are close to each other on one substrate, Alternatively, it is preferable that they are mounted at equal intervals.

  For example, it is preferable that the first and second light source circuits are formed on the flexible substrate, and the LED package of each light source circuit is mounted so that the light from the light emitting unit is mixed, and it is easy to use as a stripe light source. Become. Alternatively, the light emitting portions of the first and second light source circuits may be formed in a single light emitting region on the COB substrate to constitute a single light source.

  When performing special lighting effects such as changing the direction of light emitted from the lighting device and the place of light emission according to the duty ratio, the light source circuits may be separately arranged at positions where the respective lights are not mixed with each other.

(Control circuit)
The control circuit 101 has power input terminals 151 and 152 from the pulse power source, and has output terminals 153, 154, 155 and 156 to the first light source circuit and the second light source circuit. The terminal to the light source circuit on the side not connected to the switching circuit may be common.

  A plurality of light source circuits may be connected in parallel from each output terminal, and the light output of the entire light emitting device can be adjusted by the number of light source circuits while maintaining the light emission color change characteristics in constant voltage driving. . Therefore, it is also suitable to use a stripe light source in which light source circuits connected in parallel are arranged in a straight line with the control circuit of the present invention and used as a light emitting device capable of adjusting the emission color.

  The control circuit may be configured by a discrete element or may be configured as an IC.

  Apart from the light source circuit, only the control circuit is modularized, so that the light source circuit can be selected in accordance with the light emission characteristics desired by the lighting manufacturer and the user.

  Alternatively, the control circuit 101 may be disposed on the second light source circuit 12, and the first and second light source circuits 11 and 12 may be directly connected in parallel from the pulse power source, and wiring connection is facilitated. Further, the light emitting device 100 may be formed as a light source module including the first and second light source circuits 11 and 12 and the control circuit 101, and the handling becomes easy.

(Capacitor)
The capacitor C1 can be any type of capacitor such as an electrolytic capacitor, a ceramic capacitor, or an electric double layer capacitor.

  The capacitance of the capacitor C1 is preferably 1 pF or more, for example. The time constant for charging, which is the product of the capacitance of the capacitor C1 and the resistance values of the resistors R1 and R2 divided by the sum of the resistors R1 and R2, is preferably 1/100 or more of the cycle. Preferably, by setting the charging time constant to 1/10 or more of the cycle, a region of the duty ratio where the signal potential Vs is lower than the threshold potential is set, and the light emission aspect is changed according to the duty ratio. Becomes easy.

(resistance)
The resistors R1 and R2 are preferably resistor elements or wiring resistors printed on a substrate. Alternatively, an electric component having another resistance such as an inductor, thermistor, or diode may be used, or it may be used in combination with a resistance element.

  Each resistor may be a variable resistor, and the light emission change of the light emitting device with respect to the pulse power input waveform can be controlled by adjusting the resistance value.

(Switching element)
The switching element Q1 uses a field effect transistor, and N-type and P-type are appropriately selected depending on the circuit configuration. Further, a bipolar transistor or the like may be used.

(Embodiment 2)
As shown in FIG. 9, the light emitting device 200 according to the second embodiment of the present invention includes light source circuits 21 and 22 that include light emitting units that emit different emission colors, and a control circuit 201, as in the first embodiment. The light source circuits 21 and 22 and the control circuit 201 are powered by a pulse output power source, and the control circuit 201 includes a signal generation circuit 202 and a switching circuit 203. The switching circuit 203 is electrically connected in series with the light source circuit 21 and the pulse output power source, and the energization to the light source circuit 21 is controlled by the switching circuit 203.

  In the present embodiment, the control signal from the signal generation circuit 202 is the signal potential Vs 2, and the signal potential Vs 2 is connected to the switching circuit 203 that controls energization to the first light source circuit 21. The switching circuit 203 includes a NOT circuit. When the switching element Q21 is turned on by the signal potential Vs2, the switching element Q22 is turned off and the current supply to the first light source circuit 21 is cut off.

  As in the first embodiment, the signal potential Vs2 varies due to charging / discharging of the capacitor C2 by pulse power input, but the signal generation circuit 202 has a desired light emission change characteristic according to the waveform of the pulse power input. The resistance values of the first resistor R21 and the second resistors R22, R23 and the capacitance of the capacitor C21 are preferably set as appropriate. In the present embodiment, the second resistor on the bypass circuit is divided into two resistors R22 and R23, and the signal potential Vs2 is obtained from the middle point.

  Alternatively, as shown in the circuit diagram of the control circuit 2011 in FIG. 10, the switching circuit is switched from on to off by using the fact that the signal potential Vs21 is lowered by charging the capacitor C22 without using the NOT circuit. It may be broken.

  In the present embodiment, a simulation was performed in the same manner as in the first embodiment on the ratio of the energization time to the first light source circuit 21 with respect to the duty ratio. In the simulation, the power supply voltage is 12 V, the resistance values of the resistors R21, R22, and R23 are 10 KΩ, 3.5 KΩ, and 1.5 KΩ, the capacitance of the capacitor C1 is 0.1 μF, and the threshold voltage of the signal potential Vs2 is set. The current flowing through the switching circuit 203 was ignored at 0.7V. FIG. 11 shows the results of a simulation at a frequency of 1 KHz and a frequency of 10 KHz of pulse power input.

  In the region where the duty ratio is small, the energization time ratio to the first light source circuit 21 increases in proportion to the duty ratio until the signal potential Vs2 begins to exceed the threshold potential within the pulse power input ON period. When the signal potential Vs2 starts to exceed the threshold potential, the switching circuit 203 is turned off during the period when the threshold potential is exceeded even during the pulse power input ON period, and the signal potential Vs2 is increased as the duty ratio increases. As a result, the energization time ratio to the first light source circuit 21 gradually decreases. If the duty ratio is further increased and the signal potential Vs2 always exceeds the threshold potential, the switching circuit is always turned off and no current flows to the first light source circuit 21.

  If pulse power is input at a high frequency so that the time variation of the potential at both ends of the capacitor C21 is small, the time variation of the signal potential Vs is also small. As shown in the simulation of FIG. As shown in the simulation result of the frequency of 10 KHz in FIG. 11, the ratio of the energizing time to the light source circuit 21 with respect to the duty ratio is more steep with respect to the duty ratio. Change.

  In the light emitting device 200, when the duty ratio of the pulse power input is small, both the light emitting units of the first and second light source circuits 21 and 22 emit light at an energization time ratio proportional to the duty ratio, and there is a duty ratio. Is larger, the light emission intensity is gradually reduced by decreasing the energization time ratio to the light emitting unit on the light source circuit 21, while the energization time ratio to the light emitting unit on the light source circuit 22 is proportional to the duty ratio. Increasing the emission intensity. When the duty ratio is further increased, no current flows through the light source circuit 21, and only the light emitting unit on the light source circuit 22 emits light. As described above, the light emitting device 200 can realize the change in the emission color by adjusting the duty ratio. Similarly to the first embodiment, the light output and the emission color can be adjusted by the pulse power input waveform such as the frequency.

(Embodiment 3)
As shown in FIG. 12, the light emitting device 300 according to Embodiment 3 of the present invention includes light source circuits 31 and 32 that include light emitting units that emit different emission colors as in Embodiment 1, and a control circuit 301. The light source circuits 31 and 32 and the control circuit 301 are supplied with power from a pulse output power source, and the control circuit 301 includes a signal generation circuit 302 and switching circuits 303 and 304. The switching circuit 303 is electrically connected in series with the light source circuit 31 and the pulse output power source, and the switching circuit 304 is electrically connected in series with the light source circuit 32 and the pulse output power source. Energization is controlled.

  In the present embodiment, the control signals from the signal generation circuit 302 are two signal potentials Vs31 and Vs32. The signal potential Vs31 is connected to a switching circuit 303 having a NOT circuit for controlling energization to the first light source circuit 31, and the signal potential Vs32 is connected to a switching circuit 304 for controlling energization to the second light source circuit 32. Note that both switching circuits may be controlled by one signal potential.

  In order for the light emitting device 300 to obtain signal potentials Vs31 and Vs32 having desired light emission change characteristics, the resistance values of the first resistor R31, the second resistors R32, and R33 on the signal generation circuit 302 and the capacitance of the capacitor C31 are appropriately set. It is preferred that In addition, a separate signal generation circuit may be provided for each of the signal potentials Vs31 and Vs32.

  As the first and second light source circuits 31 and 32 are electrically connected to the switching circuits 303 and 304, respectively, the duty ratio and frequency of the pulse power input as shown in the first and second embodiments. Thus, the currents flowing through the respective light source circuits 31 and 32 are controlled.

  For example, if the switching element Q32 of the switching circuit 303 is on and the switching element Q33 of the switching circuit 304 is off in a region where the duty ratio is small, current flows only through the first light source circuit 31 and is proportional to the duty ratio. Thus, the energization time ratio to the first light source circuit 31 changes. When the duty ratio increases and the signal potential Vs31 begins to exceed the threshold potential, the energization time ratio flowing through the first light source circuit gradually decreases, and when the signal potential Vs32 begins to exceed the threshold potential, The energization time ratio to the second light source circuit 32 is increased. If the duty ratio further increases and the signal potentials Vs31 and Vs32 always exceed the threshold potential, the switching element Q32 of the switching circuit 303 is turned off, the switching element Q33 of the switching circuit 304 is turned on, and the second Current flows only through the light source circuit 32.

  As described above, the light emitting device 300 emits only the emission color of the first light source circuit in the region where the duty ratio is small, and emits the mixed color of the first and second light source circuits when the duty ratio increases, and further increases the duty ratio. Then, only the emission color of the second light source circuit is emitted. Since the duty ratio region in which current flows only in the first light source circuit 31 and the duty ratio region in which current flows only in the second light source circuit 32 as described above, the toning range of the light emitting device 300 is widened. ,preferable.

  If pulse power is input at a high frequency so that the time variation of the potential at both ends of the capacitor C31 is small, the on / off of the switching elements Q32 and Q33 on the switching circuit changes more rapidly with respect to the change of the duty ratio. . Therefore, with respect to the change of the duty ratio, the area of the duty ratio where the current flows in both the first and second light source circuits to generate the mixed color is small, and the emission color of the first light source circuit 31 or the second It is also possible to provide a light emitting device that emits light in any one of the light emission colors of the light source circuit 32. For example, only the light emitting part of the first light source circuit 31 emits light when the duty ratio ranges from 0 to 50%, and only the light emitting part of the second light source circuit 32 emits light when the duty ratio ranges from 60 to 100%. Is possible.

  At this time, in the duty ratio region where the first light source circuit 31 emits light, the energization time ratio is proportional to the duty ratio, and even in the duty ratio region where the second light source circuit 32 emits light, the energization time ratio corresponds to an increase in the duty ratio. Therefore, by adjusting the duty ratio in each duty ratio region, it is possible to control the time-average current amount flowing to each light source circuit and independently adjust the brightness in different emission colors.

  Furthermore, it is also possible to emit mixed colors from the light emitting device 300 by changing the duty ratio at high speed and switching between two light emission colors at high speed.

  That is, in Embodiment 3 of the present invention, it means that the emission color and the brightness can be independently adjusted only by the waveform control of the pulse power input. With this method, the dimming control is simple and can be downsized without using a complicated method such as controlling the current flowing in each light source circuit individually by external signal input. A control circuit for the color can be realized.

  In addition, since the adjustment of the light output and the emission color of the light emitting device of the present invention can be realized by controlling only the pulse output power source, it can be simplified as an illumination control system. For example, by giving a pulse output power supply a signal that continuously changes from an off state to a duty ratio of 100% by rotating the knob and a signal that changes the frequency by pushing the knob, the emission color gradually increases with changes in brightness. It is possible to realize a simple user interface that provides a mode that changes the brightness and a mode that adjusts the brightness for each of the two colors using only a knob.

(Embodiment 4)
As shown in FIG. 13, the light emitting device 400 according to Embodiment 4 of the present invention includes light source circuits 41, 42, 43 having a light emitting unit that emits three different emission colors, and a control circuit 401. The light source circuits 41, 42, 43 and the control circuit 401 are supplied with power from a pulse output power source, and the control circuit 401 includes signal generation circuits 402, 403 and switching circuits 404, 405, 406. The switching circuit 404 is electrically connected to the light source circuit 41 and the pulse output power supply in series, the switching circuit 405 is electrically connected to the light source circuit 42 and the pulse output power supply in series, and the switching circuit 406 is connected to the light source circuit 43 and the pulse output power supply. The power supply is electrically connected in series with the power source, and energization is controlled by each switching circuit.

  In the present embodiment, the control signal from the signal generation circuit 402 is two signal potentials Vs41 and Vs42, and the control signal from the signal generation circuit 403 is two signal potentials Vs43 and Vs44.

  The signal potential Vs41 is connected to a switching circuit 404 that controls energization of the first light source circuit 41, and the signal potentials Vs42 and Vs43 are connected to a switching circuit 405 that controls energization to the second light source circuit 42, and the signal potential Vs44. Is connected to a switching circuit 406 that controls energization to the third light source circuit 44. Switching circuits 404 and 405 include NOT circuits, and switching circuit 405 includes switching elements Q43 and Q44 in series.

  In order for the light emitting device 400 to obtain signal potentials Vs41, Vs42, Vs43, and Vs44 having desired light emission change characteristics, the first resistor R41, the second resistors R42 and R43 on the signal generation circuit 402, and the signal generation circuit 403 are obtained. The resistance values of the first resistor R4a, the second resistors R4b, R4c and the capacitances of the capacitors C41, C42 are preferably set as appropriate.

  Note that a signal generation circuit may be provided for each signal potential Vs. Alternatively, all signal potentials Vs may be obtained from a single signal generation circuit.

  The duty ratio at which the signal potentials Vs41 and Vs42 reach the threshold potential for switching on and off of the switching circuits 404 and 405 connected within the pulse power input ON period, respectively, The duty ratio is preferably smaller than the duty ratio that reaches the threshold potential for switching on / off. The duty ratio increases from 0% in order of the first light source circuit 41, the second light source circuit 42, and the third light source circuit 43. The energization can be switched.

  Specifically, when the duty ratio is small, the switching elements Q42, Q43, Q44, and Q46 in the switching circuit are on, off, on, and off, and current flows only through the first light source circuit 41. In the pulse power input ON period in which the duty ratio increases and the signal potentials Vs41 and Vs42 exceed the threshold potential, the respective switching elements Q42, Q43, Q44, and Q46 are turned off, on, on, off, and the second light source A current flows only in the circuit 42. In the pulse power input ON period in which the duty ratio is further increased and the signal potentials Vs43 and Vs44 exceed the threshold potential, the respective switching elements Q42, Q43, Q44, and Q46 are turned off, on, off, on, and the third A current flows only in the light source circuit 43.

  If pulse power is input at a high frequency such that the time variation of the potentials at both ends of the capacitors C41 and C42 is small, the time variation of the signal potential is also small, and the first light source circuit has a duty ratio of 0 to 100%. The duty ratio area where only the light emitting part on 41 emits light, the duty ratio area where only the light emitting part on the second light source circuit 42 emits light, and the duty ratio area where only the light emitting part on the third light source circuit 43 emits light. It is possible to set the value of the capacitor and the resistance so that they exist in each other, and it is possible to control the amount of time average current flowing in each light source circuit by further adjusting the duty ratio within the range of the respective duty ratios .

  With the above, it is possible to adjust the light output of the three colors using the three light source circuits having different emission colors. For example, the light emitting part of each light source circuit is formed of a red (R) LED package and a green (G) LED. If a package, a blue (B) LED package, or an RGB LED package connected to each switching circuit is used, a so-called multicolor light emitting device can be realized. Similarly, by increasing the number of switching circuits and light source circuits, it is possible to emit light of four or more colors such as RGBW with white (W) added.

  In addition, by changing the duty ratio of the pulse output power supply at high speed and switching the emission color between red, green and blue in a short time, the light emitting device can emit mixed colors and emit light at any chromaticity point Color output is also possible. In addition, for example, it is possible to provide a multicolor light emitting device in which the light emission color is switched according to time by continuously changing the duty ratio.

  Each switching circuit may have a storage capacitor. As shown in a switching circuit 4061 in FIG. 14 which is a modified example of the switching circuit 406, the transistor Q47 is turned on by the signal potential Vs44. While the holding capacitor C43 is charged, the switching element Q49 is turned on, and the light source circuit 43 emits light through the output terminal 458. If charges are stored in the holding capacitor C43, even if the signal potential Vs44 fluctuates due to a change in the duty ratio of the pulse output power supply, the charge stored in the holding capacitor C43 turns on the switching element Q49. During the ON period, the light source circuit 43 emits light through the switching circuit 4061.

  Since the holding voltage applied to the switching element Q49 according to the ON time of the transistor Q47 is determined by the resistance value of the resistor R4d and the holding capacitor C43, the amount of current flowing through the switching circuit 4061 to the light source circuit 43 is determined by the time when the Vs44 is turned ON. It can also be controlled. In order to prevent discharge of the capacitor C43 when the input is off, it is preferable to connect a diode D1.

  In order to turn off the switching circuit 4061, by applying a voltage in the opposite direction, the transistor Q48 is turned on, and the switching element Q49 is turned off by discharging the charge stored in the holding capacitor C43. Alternatively, a duty ratio section different from the signal generation may be provided to give a signal for turning on the switching element for discharging the holding capacitor. Alternatively, a third input wiring may be provided, and the holding capacitor may be discharged by electrical input from the third input wiring.

  If each switching circuit similarly has a holding capacitor, it is possible to emit light simultaneously from each light source circuit during energization in a duty ratio section different from signal generation and holding capacitor discharge. For example, as shown in FIG. 15, after the pulse power input is input for Tr, Tg, Tb time with a duty ratio that becomes an ON signal to each switching circuit, and the current flowing to each RGB light source circuit is set by charging the holding capacitor If the Ton time energization is performed in another duty ratio section that does not affect each signal potential, the Ton time RGB light source circuit can emit light at a desired emission intensity ratio.

  A small multi-color LED device such as a micro LED in which the control circuit is an element formed by a semiconductor process and the LED element is directly mounted on the control circuit element may be configured. Since no input is required, the number of connection points with the substrate side can be reduced, which is preferable in terms of mounting.

  As shown in FIG. 16, the light emitting device 500 having the control circuit 501 of the present invention and the light source circuit including the RGB LED elements is arranged on the matrix of the power input wirings 561 and 562, so that light emission by pulse power input is performed. It may be used as a color display by color setting and light emission of mixed colors, and the required wiring can be greatly reduced compared to a method of individually controlling RGB.

  For example, only the wirings 561a and 562a are instantaneously reversed in polarity, the holding capacitor of the light emitting device 500aa connected to the wirings 561a and 562a on the circuit is discharged, and the wiring 562a and the wiring 562c are deenergized, and the pulse is transmitted from the wiring 561a. The light emission color of the light emitting device 500aa can be set by power input. By performing this operation with each set of wirings, it is possible to set the light emission color of the light emitting device 500 arranged on the matrix and display it as a color display as a whole.

  Each light source circuit may be provided with a capacitor in parallel with the light emitting element so that light emission can be maintained for a short time even when no power is supplied. It is preferable that a diode is provided in series on the wiring of the light source circuit so that the discharge of the capacitor does not affect the signal generation circuit. Further, when the switching circuit is turned off, the influence of the afterimage can be eliminated by the circuit configuration in which the capacitor of the light source circuit is also discharged.

  As another reference form, the signal generation circuit may be another circuit that detects the waveform of the pulse power input and applies the signal potential Vs. For example, as shown in FIG. A microcomputer 606 may be used, and the emission color and brightness can be changed arbitrarily according to the duty ratio.

  The microcomputer 606 detects the duty ratio and frequency of the pulse power input, the length of the on-time, and the like based on the fluctuation of the potential Vp obtained by the divided voltage of the resistors R9 and R10, so that the light emitting device has the desired light emission characteristics. Signal potentials Vs61 and Vs62 are applied to the switching circuit. For example, the program of the microcomputer 606 can receive various combinations of the signal potentials Vs61 and Vs62 in response to the combination of the duty ratio and frequency of the pulse power input, and more arbitrarily control the emission color and brightness of the light emitting device. Furthermore, the relationship of the emission color change with respect to the duty ratio may be changed by the microcomputer 606 detecting whether the power input is turned on or off.

  Preferably, the pulse power input is a rectangular wave with a constant voltage, a regulator is not required for the power supply to the microcomputer 606, the waveform of the pulse power input can be easily detected only by the voltage threshold, and the light source circuit has only a limiting resistor. The current can be controlled by this, and light can be emitted immediately in the on-time.

  A capacitor C61 is preferably connected in parallel to the power supply potential Vc to the microcomputer 606, and a constant drive voltage is ensured even during the off time of the pulse power input.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope shown in the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments, respectively. Is also included in the technical scope of the present invention.

  In Example 1, a test was performed using a light-emitting device having the same structure as that of Embodiment 1.

  In the control circuit 102, R1 is 15 KΩ, R2 is 5.9 KΩ, the capacitor C1 is 0.1 μF, and a Toshiba field effect transistor 2SK4017 is used as a switching element.

  A 12V constant voltage pulse modulation output power source is used as the pulse output power source, and an LED package showing a light emission color with a color temperature of 2800K is used as the light emitting portion of the first light source circuit directly connected to the pulse output power source, which is connected to the switching circuit. For the light emitting part of the second light source circuit, an LED package showing an emission color with a color temperature of 4000K was used. The current flowing through each light source circuit during energization was adjusted according to the resistance value on each light source circuit.

  When the output frequency of the pulse output power source was 1 KHz and 10 KHz, the current value to each light source circuit for each duty ratio of the pulse output power source, the emission color of the light emitting device, and the relative luminous flux were confirmed. Since the current is supplied by the pulse output power source, the current value of each light source circuit is a time averaged value. The luminescent color and relative light flux of the light emitting device were measured by the mixed light from the light emitting part of the first light source circuit and the light emitting part of the second light source circuit.

  FIG. 18 shows changes in the magnitude of current flowing through each light source circuit with respect to the duty ratio. The current flowing through the first light source circuit is proportional to the duty ratio of the pulse power supply output, but the current flowing through the second light source circuit was simulated for the energization time ratio of the second light source circuit in FIGS. Shows the same change.

  FIG. 19 is a graph showing changes in the color temperature of the emitted color with respect to the relative luminous flux emitted from the light emitting device. It can be seen that the color temperature of the emission color changes with respect to the change of the relative luminous flux according to the duty ratio of the pulse power input from the pulse output power supply. It can also be seen that the emission color change shows a different aspect depending on the difference in the output frequency of the pulse output power source between 1 KHz and 10 KHz.

  In Example 2, a test was performed using a light-emitting device having a structure similar to that of Embodiment 3.

  R31 of the control circuit 102 is 15 KΩ, R32 is 3.9 KΩ, R33 is 2 KΩ, a capacitor is 0.1 μF, Toshiba field effect transistor 2SK4017 is used as switching elements Q32 and Q33, and switching element Q31 is Toshiba transistor 2SC1815. Was used.

  As in the first embodiment, a 12V constant voltage pulse modulation output power source is used as the pulse output power source, and the light emitting portion of the first light source circuit connected to the switching circuit 303 controlled by the NOT circuit has a light emission color with a color temperature of 2800K. The LED package which shows the luminescent color of the color temperature 4000K was used for the light emission part of the 2nd light source circuit connected with the switching circuit 304. FIG. The current flowing through the light source circuit during energization was adjusted by the resistance value on each light source circuit.

  The output frequency of the pulse output power source was set to 1 KHz and 10 KHz, and changes in the current value to each light source circuit, the color temperature of the emitted color, and the relative luminous flux with respect to the duty ratio of the pulse output power source were confirmed. Since the current is supplied by the pulse output power source, the current value of each light source circuit was measured as a time averaged value.

  FIG. 20 shows changes in the magnitude of the current flowing through each light source circuit with respect to the duty ratio. It can be seen that the ratio of the current value flowing through the first and second light source circuits varies depending on the duty ratio. In particular, when the output frequency of the pulse output power supply is 10 KHz, it can be seen that the light source circuit through which current flows at a duty ratio of 50 to 55% is rapidly switched.

  Therefore, as shown in FIG. 21, as the duty ratio increases, the light emission color emitted from the light emitting device changes from the light emission color 2800K of the first light source circuit to the light emission color 4000K of the second light source circuit. If the pulse output frequency is 10 KHz, the color temperature changes abruptly according to the switching of the current.

  In addition, as shown in FIG. 22, the brightness also changes depending on the duty ratio. Particularly, when the output frequency of the pulse output power source is 10 KHz, in the region where the duty ratios are 50% and 55% or later, the emission colors are different. The brightness could be adjusted according to the duty ratio.

  In Example 3, a test was performed using a light-emitting device having a structure similar to that of Embodiment 4.

  The resistors R41, R42, R43, R4a, R4b, and R4c of the control circuit 401 use 10KΩ, 2KΩ, 1.8KΩ, 9KΩ, 2KΩ, and 800Ω, respectively, the capacitors C41 and C42 use 0.1 μF, and the switching element Q41 , Q42, Q43, Q44, Q45, and Q46 used Toshiba transistor 2SC1815.

  A 12 V constant voltage pulse modulation output power source is used as the pulse output power source. The light source of the first light source circuit 41 is a red LED package, the light source of the second light source circuit 42 is a green LED package, and the third light source circuit 43 The light emitting part used a blue LED package. The current flowing through each light source circuit during energization was adjusted according to the resistance value on each light source circuit.

  FIG. 23 shows a change in the magnitude of the current of each light source circuit with respect to the duty ratio when the output frequency of the pulse output power supply is 10 KHz. When the duty ratio is 0 to 35%, the first light source circuit having the red LED package is mainly energized, and when the duty ratio is 45 to 70%, the second light source circuit having the green LED package is mainly energized. It can be seen that up to ˜100% is energized mainly to the third light source circuit having the blue LED package. It was confirmed that light emission of different colors of red, green, and blue can be obtained depending on the duty ratio, and the current amount to each light source circuit can be individually controlled by adjusting the duty ratio in each light emission color region.

DESCRIPTION OF SYMBOLS 10 Pulse modulation output power supply 20 Power supply control device 30 Constant output power supply 40 Pulse control device 11, 21, 31, 41, 61 1st light source circuit 12, 22, 32, 42, 62 2nd light source circuit 43 3rd Light source circuit 100, 200, 300, 400, 500, 600 Light emitting device 101, 1011, 201, 2011, 301, 401, 501, 601 Control circuit 102, 1021, 202, 2021, 302, 402, 403, 602 Signal generation circuit 103, 203, 2031, 303, 304, 404, 405, 406, 4061, 603, 604 Switching circuit 104 Pulse circuit 105 Pulse power waveform detection circuit 606 Microcomputer 151, 152, 251, 252, 2511, 2521, 351, 352 , 451, 452, 651, 652 Input terminal 153,154,155,156,253,254,255,256,2531,2541,2551,2561,353,354,355,356,453,454,455,456,457,458,653,654 655,656 Output terminal 561,562 Pulse power input wiring

Claims (5)

A signal generation circuit electrically connected to a pulse power source serving as a power supply source to a plurality of light source circuits having a light emitting unit;
A switching circuit electrically connected to at least one of the light source circuits;
The signal generation circuit includes a first resistor and a capacitor in series,
The capacitor includes a bypass circuit including a second resistor;
The switching circuit includes a switching element,
The control circuit of the light emitting device, wherein the control signal from the signal generating circuit is an on signal or an off signal of the switching circuit according to a waveform of the pulse power source. The switching circuit electrically connected to the light source circuit is plural,
The waveform of the pulse power source that provides a combination of the control signals that turns on only one of the switching circuits and turns off the other switching circuit exists for each of the switching circuits. The control circuit of the light-emitting device according to claim 1. The signal generation circuit includes an auxiliary switching element in parallel with the capacitor,
The auxiliary switching element includes at least one of an auxiliary capacitor and an auxiliary resistor in series,
The light emitting device control circuit according to claim 1, wherein the auxiliary switching element is turned on / off according to the waveform of the pulse power source. The switching circuit includes a storage capacitor;
2. The control circuit for a light emitting device according to claim 1, wherein a current flowing from the light source circuit to the switching circuit is controlled based on a voltage held in the holding capacitor. A plurality of the light source circuits having the light emitting section;
The emission color from the light emitting unit on at least one of the light source circuits is different from the emission color from the light emitting unit on the other light source circuit,
A light emitting device comprising the control circuit according to claim 1.

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