JP2007005258A - Lighting system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lighting system using such a solid light-emitting element that a unified light modulation is feasible by using a light modulation signal used for a fluorescent lamp luminaire even when the lighting system is used concurrently with the fluorescent lamp luminaire. <P>SOLUTION: A light modulation signal that is used for light modulation in a fluorescent lamp luminaire and that has an on-duty ratio inversely proportional to a light modulation ratio of a light source is inverted by an inverter circuit 3a provided in a light modulation means 3, and the signal thus inverted is used for a switching operation of a switching element 3b to thereby allow the solid light-emitting element 1 to emit light. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a lighting device using a solid light emitting element as a light source.

  In recent years, organic EL devices have been actively studied as thin solid-state light emitting devices. An organic EL device is a device in which a thin light emitting layer made of an organic compound is sandwiched between electrodes and emits light when a current is supplied between the electrodes. The organic EL element can be configured as a thin and lightweight light-emitting element, and the driving voltage is about several to several tens of volts, which is lower than that of a discharge lamp that is a conventional mainstream light source. Application to thin and lightweight lighting fixtures can be expected.

  By the way, in using an illuminating device, dimming of the illuminating device is generally performed from the viewpoint of power saving and lighting performance, and is described in Patent Document 1 as an illuminating device using a conventional organic EL element. There is something.

As shown in FIG. 4, this conventional example includes a converter means 20 that converts AC power supplied from an AC power source PS into DC power, and an organic EL element by turning on / off the DC current supplied from the converter means 20. Switching means 30 for intermittently supplying a forward current to 10 and control for switching on / off of the switching means 30 at a switching frequency higher than that of the AC input power supply PS and controlling the on-duty ratio of the switching means 30 The on-duty ratio is controlled by the control means 40 so that a desired brightness value is obtained by an external dimming mechanism that can be adjusted to a desired brightness by a dial or the like. The organic EL element 10 is caused to blink by turning on / off the switching means 30 according to the on-duty ratio. It is made to. Here, since the switching means 30 performs switching at a frequency higher than that of the AC power supply PS, the flickering of luminance is prevented and the light emission life is improved. In addition, by controlling the on-duty ratio variably in the control means 40, a desired luminance can be obtained.
JP-A-2005-78828

  By the way, the illumination device as in the above conventional example is used in combination with a dimming type fluorescent lamp lighting fixture, and the lighting device and the fluorescent lamp lighting fixture are simultaneously used by the dimming controller for the fluorescent lamp stabilizer of the fluorescent lamp lighting fixture. The case of dimming is considered. In the combination of this type of dimming controller and fluorescent lamp luminaire, the dimming signal used for dimming is directly proportional to the dimming ratio (brightness with 100% when fully lit) and on-duty ratio. Any one of the dimming signal and the dimming signal in which the dimming ratio and the on-duty ratio are inversely proportional to each other are used. When using dimming signals that are directly proportional, when the dimming ratio is increased by the dimming controller, both the lighting device and the fluorescent lamp illuminator will be bright, but there is no problem, but there is an inversely proportional relationship. When a dimming signal is used, when the dimming ratio is increased by the dimming controller, the illumination is brightened in the fluorescent lamp luminaire, while the illuminator is dimmed and the illumination becomes dark. There was a problem that dimming was not unified.

  The present invention has been made in view of the above problems, and provides an illuminating device in which dimming can be unified by a dimming signal used in a fluorescent lamp illuminator even when used simultaneously with the fluorescent lamp illuminator. With the goal.

  In order to achieve the above object, the first aspect of the present invention controls the dimming of the light source by turning on and off the application of a DC voltage to the solid state light emitting device and the solid state light emitting device based on a dimming signal from the outside. A lighting device using a pulse width modulation signal in which the on-duty ratio and the brightness of the light source are inversely proportional to each other. A DC voltage is supplied to the solid state light emitting device so that the voltage application time per unit time is shortened as the on-duty ratio of the dimming signal increases, and per unit time as the on-duty ratio of the input dimming signal decreases. The direct current voltage is supplied to the solid state light emitting device so that the voltage application time is longer.

  According to a second aspect of the present invention, in order to achieve the above object, the dimming means inverts a dimming signal composed of binary values of Hi and Lo and outputs the inverted signal to the control terminal of the switching element, and solid state light emission The switching element is connected in series with the element and turned on when the signal input to the control terminal is at the Hi level, supplies a DC voltage to the solid state light emitting element, and turns off when the signal is at the Lo level.

  According to the present invention, a dimming signal in which the dimming ratio and the on-duty ratio are inversely proportional to each other is used by reversing, so that a fluorescent lamp illuminator and a lighting device using a solid light emitting element can be used simultaneously. However, the dimming can be unified by the dimming signal of the dimming controller used for the fluorescent lamp lighting apparatus.

(Embodiment 1)
Hereinafter, a first embodiment of the present invention will be described with reference to FIG. In the present embodiment, application of a DC voltage to the solid state light emitting element 1 is turned on and off based on a dimming signal from the solid state light emitting element 1 serving as a light source and a dimming controller 2 used for dimming the fluorescent lamp luminaire. And a dimming means 3 for dimming the solid state light emitting device 1.

  The solid-state light emitting element 1 emits light when a direct current voltage is applied in a specified direction like an organic EL element, for example, and is driven by a direct current voltage supplied from a direct current power source. The dimming is performed by changing the light emission time per unit time by turning on and off the application of the DC voltage. In addition to the organic EL element, other solid light emitting elements such as a light emitting diode may be used.

  An operation unit 2a and a power switch 2b are provided on the front surface of the dimming controller 2. The operation unit 2a is a lever that changes the resistance value of the variable resistor incorporated in the dimming controller 2 by sliding in the vertical direction in the figure, and performs pulse width modulation according to the dimming ratio corresponding to the resistance value. The adjusted dimming signal is output. With the dimming signal, the dimming ratios of the fluorescent lamp lighting fixture and the lighting device using the solid light emitting element 1 can be adjusted simultaneously. Here, the dimming signal is a pulse width modulation signal composed of binary values of Hi and Lo, and the dimming signal output from the dimming controller 2 has a dimming ratio and an on-duty ratio in an inversely proportional relationship. When the light knob 2a is slid in the upper direction, that is, the direction in which the dimming ratio is increased, the on-duty ratio is decreased, and when the light knob 2a is slid in the lower direction, that is, in the direction in which the dimming ratio is decreased, the on-duty ratio is increased. It has become. The power switch 2b turns on / off AC power supplied from an AC power source that is a power source of the dimming controller 2.

  The dimming means 3 is connected in series to the inverting circuit 3a that inverts the dimming signal consisting of binary values of Hi and Lo and outputs it to the control terminal of the switching element, and is input to the control terminal. The switching element 3b is turned on when the signal is at the Hi level, supplies a DC voltage to the solid state light emitting element 1, and is turned off when the signal is at the Lo level. Since the dimming signal generally has a voltage of 10 V and a frequency of 1 kHz, if the switching element 3b is a MOSFET that can be driven even at a low voltage, it can be directly driven by the dimming signal. When the switching element 3b is not directly driven, a dimming signal may be used as a control signal for the switching element 3b and a buffer circuit may be provided for driving.

  The operation of the present invention will be described below. The solid-state light emitting element 1 is connected in series with a DC power source and the light control means 3, and flashes and emits light by turning on / off the DC voltage by switching on / off the switching element 3 b of the light control means 3. The switching element 3b is driven by a pulse width modulation signal obtained by inverting the dimming signal output from the dimming controller 2 by the inverting circuit 3a, and the switch is turned on when the pulse width modulation signal is Hi so that the solid state light emitting element DC voltage is supplied to 1 and the switch is turned off when Lo.

  For example, when compared with the brightness in the case of the dimming signal having an on-duty ratio of 50% shown in FIG. 2B, the inversion circuit in the case of the dimming signal having an on-duty ratio of 25% as shown in FIG. 3a is converted into a pulse width modulation signal having an on-duty ratio of 75%, and the switching element 3b is driven by this signal. Therefore, the voltage application time per unit time is increased, and the brightness of the solid-state light-emitting element 1 has an on-duty ratio. Brighter than 50%. In the case of a dimming signal with an on-duty ratio of 75%, as shown in FIG. 5C, the inverter circuit 3a converts it to a pulse width modulation signal with an on-duty ratio of 25%, and this signal drives the switching element 3b. Therefore, the voltage application time per unit time is shortened, and the brightness of the solid state light emitting device 1 becomes darker than that when the on-duty ratio is 50%. As described above, the dimming of the lighting device and the fluorescent lamp illuminating device is unified by using the dimming signal output from the dimming controller 2 in the lighting device by inverting it.

(Embodiment 2)
Hereinafter, a second embodiment of the present invention will be described with reference to FIG. This embodiment has substantially the same basic configuration and operation as the first embodiment, but a plurality of solid state light emitting devices 1 are connected in series as shown in FIG. Dimming is performed by the dimming means 3 connected to the. In the first embodiment, the DC power source is used as the power source of the solid state light emitting device 1. However, in this embodiment, the AC voltage supplied from the AC power source used in the dimming controller 2 is changed to a full-wave AC voltage. A smooth DC voltage is made through a rectifier circuit 4 comprising a diode bridge circuit 4a and an electrolytic capacitor 4b for rectification, and a plurality of solid state light emitting devices 1 are caused to emit light using this DC voltage. Further, as in the first embodiment, these solid state light emitting elements 1 emit light by inputting a pulse width modulation signal obtained by inverting the dimming signal of the dimming controller 2 by the inverting circuit 3a to the switching element 3b. The lighting state is the same as in FIG.

  Assuming that the smoothing DC voltage obtained by rectifying the AC voltage is Vd, and the rated on-voltage of the solid state light emitting device 1 is Vo, the solid state light emitting device 1 can be connected in principle up to the maximum integer number not exceeding Vd / Vo. It is. However, in actuality, there is a ripple of the cycle of the AC power supply, so that the voltage fluctuates not a little. In consideration of the on-voltage and loss of the switching element 3b, the number used is one less than the theoretical number. Is desirable. Further, by using a step-up chopper circuit or a step-down chopper circuit, the smooth DC voltage can be adjusted, and an arbitrary number of solid state light emitting devices 1 can emit light.

It is a figure which shows the circuit structure of 1st embodiment of this invention. It is a figure which shows the signal waveform of the lighting state of a pulse width modulation signal and a solid light emitting element. It is a figure which shows the circuit structure of 2nd embodiment of this invention. It is a figure which shows the circuit structure of the illuminating device which used the conventional organic EL element as the light source.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Solid light emitting element 2 Dimming controller 2a Dimming knob 2b Power switch 3 Dimming means 3a Inversion circuit 3b Switching element

Claims (2)

  A solid-state light-emitting element serving as a light source; and a light-modulating means for dimming the light source by turning on and off the application of a DC voltage to the solid-state light-emitting element based on a light-control signal from the outside. A lighting device using a pulse width modulation signal in which the ratio and the brightness of the light source are inversely proportional to each other, wherein the dimming means per unit time as the on-duty ratio of the input dimming signal increases. A DC voltage is supplied to the solid state light emitting device so that the voltage application time is shortened, and the direct current voltage is applied to the solid state light emitting device so that the voltage application time per unit time becomes longer as the on-duty ratio of the input dimming signal becomes smaller. A lighting device characterized by supplying The dimming means inverts a dimming signal consisting of binary values of Hi and Lo and outputs the inverted signal to the control terminal of the switching element, and a signal connected to the solid state light emitting element in series and input to the control terminal is Hi. The lighting device according to claim 1, further comprising: a switching element that is turned on when the level is reached, supplies a DC voltage to the solid state light emitting element, and is turned off when the level is the Lo level.

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