摘要:
A light emitting device includes a set of light source units including multiple types of solid state light emitting elements having different light colors, each of the light source units comprising the same type of the solid state light emitting elements connected in series and; and an information storage unit which stores information about electrical characteristic of the set of light source units. The information stored in the information storage unit represents a relationship between a light output and a drive current in the set of light source units.
摘要:
An illumination apparatus is provided for outputting a light of mixed colors in a desired color temperature by controlling light outputs from light sources. The illumination apparatus includes a light output setting unit for outputting a set signal presenting a set value for adjusting an output of the light of mixed colors, and a first filter for smoothing the set signal from the light output setting unit. The illumination apparatus further includes a light output adjustment unit for adjusting the light outputs from the respective light sources based on the set signal smoothed by the first filter, and a plurality of second filters smoothing signals outputted from the light output adjustment unit to the light sources, respectively. Each of time constants of the second filters is lower than that of the first filter.
摘要:
A lighting device includes: a lighting unit for supplying a lighting power to a light source unit; and a controller, for controlling the lighting unit. The lighting unit has an inductor and a switching element, and a diode for flowing a flyback current of the inductor to the light source unit during an OFF period of the switching element, and the controller has a unit for intermittently driving an ON/OFF operation of the switching element by a PWM signal and a unit for driving the switching element by a frequency higher than that of the PWM signal during an ON period of the PWM signal, and when the PWM signal falls, the controller reduces a peak value of a load current flowing through the light source unit during a certain period.
摘要:
An illumination system includes a lighting apparatus having a solid-state light emitting element as a light source; and a dimmer including a bidirectional switching element having a self-sustaining function and connected to a serial circuit of the lighting apparatus and an external power source. The dimmer varies a conduction angle of the bidirectional switching element by controlling a phase of an AC voltage of the external power source, wherein the lighting apparatus performs dimming of the light source based on the conduction angle of the bidirectional switching element, and the dimmer continues to apply driving current to the bidirectional switching element during a first period, which is a part of a second period, the bidirectional switching element being allowed to conduct throughout the second period.
摘要:
A lighting device includes lighting control units respectively provided for controlling lighting of solid state light emitting element groups irradiating light of different chromaticities and a color ratio setting unit for setting a target output ratio of the solid state light emitting element groups. In an xy chromaticity diagram of an XYZ color system, a straight line connecting chromaticity coordinates of lights irradiated by a first and a second solid state light emitting element group intersects a black body locus. Further, the lighting control units include a first and a second lighting control unit for controlling lighting of the first and the second solid state light emitting element group, and the first and the second control unit perform a feedback control such that an output ratio of the second to the first solid state light emitting element group becomes equal to the target output ratio thereof.
摘要:
An illumination system includes a lighting apparatus having a solid-state light emitting element as a light source; and a dimmer including a bidirectional switching element having a self-sustaining function and connected to a serial circuit of the lighting apparatus and an external power source. The dimmer varies a conduction angle of the bidirectional switching element by controlling a phase of an AC voltage of the external power source, wherein the lighting apparatus performs dimming of the light source based on the conduction angle of the bidirectional switching element, and the dimmer continues to apply driving current to the bidirectional switching element during a first period, which is a part of a second period, the bidirectional switching element being allowed to conduct throughout the second period.
摘要:
A discharge lamp lighting device includes a rectifier, a first diode connected at the anode in forward direction to a positive polarity output terminal of the rectifier, a smoothing capacitor connected between the cathode of the first diode and a negative polarity output terminal of the rectifier, a second diode connected at the anode in forward direction to the cathod of the first diode, a pair of switching elements connected in series between the cathode of the second diode and the negative polarity output terminal of the rectifier, a first capacitor connected in parallel to one of the first diode and the rectifier, a second capacitor connected in parallel to the second diode, and a control circuit for controlling ON/OFF operation of these switching elements, and a transformer having a primary winding n11 connected between a junction point of the pair of switching elements and one of output terminals of the rectifier and a secondary winding connected to a load circuit including a discharge lamp, and their arrangement can reduce peak factor of currents flowing to the load circuit and any loss occurring at the switching elements.
摘要:
A power supply apparatus in which a full-wave rectifier is connected to an A.C. power source, a load circuit as a parallel circuit of a smoothing capacitor connected in parallel to a load is connected to outputs of the full-wave rectifier through a switching element and a capacitor, and a control means for adjusting a voltage across the capacitor is provided in parallel to the capacitor to cause a sum of voltages across the capacitor and smoothing capacitor to be proportional to an input voltage and to cause a voltage corresponding to a difference between the input and output voltages to appear across the capacitor to apply a desired constant voltage to the load, whereby an envelope line of an input current becomes proportional to the input voltage under control of switching elements. Thereby power conversion can be realized with use of a small number of switching elements, the arrangement of a control circuit can be simplified, and a peak current at the time of adjusting the voltage across the capacitor can be made small.
摘要:
A burst dimming signal to determine a ratio between an ON period and an OFF period is inputted. In the OFF period of the burst dimming signal, a lamp current Ila is stopped from flowing to a discharge lamp FL, while a lamp voltage Vla is applied to both ends of the discharge lamp FL, and preheating currents If1 and If2 are supplied to hot cathodes of the discharge lamp FL. In the ON period of the burst dimming signal, the discharge lamp FL is electrically broken down and is supplied with the lamp current Ila.
摘要:
A series circuit comprising a diode and a resistance is connected in parallel to a filament, and a series circuit comprising a diode and a resistance is connected in parallel to a filament. The filaments are preheated by a preheating current supplied from secondary windings of a preheating transformer, via preheating capacitors. Detection circuits detect DC voltage components of the preheating capacitors. Comparators compare the DC voltage components of the preheating capacitors with a reference voltage. The comparators cause a control circuit to protect the inverter circuit if an abnormality of the filaments is detected.