Abstract: An LED-based lighting apparatus is powered by multi-phase AC voltages to reduce flicker. A multi-phase AC-to-AC power generator is used to generate a plurality of AC voltages from an AC power source. The plurality of AC voltages each having a different phase are rectified by a plurality of rectifiers to provide a plurality of rectified AC voltages for a plurality of LED lighting units. Each LED lighting unit has voltage dependent brightness and reaches maximum brightness at different time due to the phase difference in the rectified AC voltage. The peak-to-peak variation in the total brightness is reduced and therefore the LED-based lighting apparatus has low flicker.

Abstract: The present invention utilizes a three-phase or multiphase AC power source, and the electric power of each phase respectively drives its corresponding solid-state light emitting member, and the solid-state light emitting members respectively driven by each phase power are arranged adjacently or arranged with an overlapping means, so that the light of the individual solid-state light emitting members respectively driven by the multiphase power source and arranged adjacently or arranged with an overlapping means can reduce the brightness pulse through synthetic illumination; and through being controlled by a solid-state switch device for controlling AC conductivity phase angle (1000) installed on the power source of each phase, when the illumination brightness of corresponding solid-state light emitting member is lower than that of other solid-state light emitting members arranged adjacently or arranged with an overlapping means, the power source is cut for saving energy.

Abstract: A driver circuit for adapting an LED lamp or an LED lamp array to be used in a lamp fitting for a non-LED type lamp without modification of the lamp fitting. The LED lamp or LED lamp array can be inserted into the lamp fitting as a replacement for a non-LED lamp. The driver circuit has a first stage with a filter circuit and having an input connectable to any of an ac power supply, an electromagnetic ballast or an electronic ballast of the lamp fitting; a second stage with a high frequency switched network and having an input connected to an output of the first stage; and a third stage with an ac/dc converter and having an input connected to an output of the second stage and an output connectable to an LED lamp. The third stage is configured to deliver dc power to a connected LED lamp. The second stage is configured to operate in a low frequency mode and in a high frequency mode.

Abstract: A discharge tube is driven by a multiple-phase drive circuit, and includes a discharge container having an internal discharge space and multiple electrodes that are secured to the discharge container and correspond to each phase of the multiple-phase drive circuit. The tips of the multiple electrodes protrude into the discharge space, and are oriented toward a predetermined single point of union. All of the electrodes located on one side of a virtual plane that includes the predetermined point of union. Furthermore, a discharge lamp having the discharge tube includes three electrodes, and electric discharge can take place between each pair of electrodes. When the discharge lamp is driven at maximum output, voltage is impressed to the three electrode terminals such that at least one of the voltages VeAB, VeBC, VeCA between the three electrode terminals will be in a discharge period.

Abstract: In a phase controller used in a light control of an incandescent lamp, noise reduction, prevention of elements from damage due to short circuit current, downsizing and lower cost are purposed. A CPU circuit of a control circuit sets a gradual increase term during which a load voltage applied to the incandescent lamp is gradually increased by driving a self-quenching type switching device such as an IGBT. After passing the gradual increase term, a main switching device such as a TRIAC is turned on. The phase controller further comprises a current sensor such as a shunt resistor for sensing a value of the load current flowing through the self-quenching type switching device, according to need. The CPU circuit compares the sensed value of the load current with at least one reference value, and selects driving manner of the main switching device and the self-quenching type switching device corresponding to the result of comparison.

Abstract: Disclosed herein is a halogen-lamp illumination/control circuit which includes a switching circuit unit for applying an a.c. power to the halogen lamp each time a firing pulse is received, a zero-crossing detection unit for detecting the timing at the time of zero-crossing of the a.c. power, a firing control unit for outputting a firing pulse each time a zero-crossing detection signal is received, and an illuminating command unit for supplying the firing pulse to the switching circuit unit during a period in which an illuminating command signal is inputted so as to make the same conductive.