Abstract: A fluorescent lamp driving method drives a fluorescent lamp by using an alternating current driving signal generated by an inverter circuit using direct current power as an input. The driving signal is supplied from the inverter circuit to a load including the fluorescent lamp. The method includes the steps of, by using a sum current detecting circuit, detecting a current change in the signal, by using a control circuit, controlling the driving signal generated by the inverter circuit on the basis of the current change detected by the sum current detecting circuit, and controlling a current of the supplied signal to be constant, by using a temperature detecting circuit, detecting the temperature of the fluorescent lamp, and, by using a correction circuit, on the basis of the temperature of the fluorescent lamp detected by the temperature detecting circuit, correcting the controlling the current of the supplied signal to be constant.

Abstract: Modular lamp system comprises a base unit comprising a power supply, and at least one pair of external electrical contacts arranged on said base unit and electrically connected with said power supply; and at least one light unit comprising at least one first pair of external electrical contacts, arranged on said light unit and arranged to mate with the at least one pair of electrical contacts of the base unit or another substantially identical unit, at least one second pair of external electrical contacts, arranged on said light unit and arranged to mate with the at least one first pair of electrical contacts of another substantially identical unit, and at least one LED lamp arranged on said light unit, said at least one first pair of external electrical contacts and said at least one second pair of external electrical contacts, and said lamp being electrically connected with each other.

Abstract: A LED control circuit and method determine the frequency and duty of a LED driving signal according to a swing control signal and a dimming control signal, respectively. Responsive to the swing control signal, a pulse edge generator generates a clock whose frequency is determined by the swing control signal. Responsive to the clock and the dimming control signal, a duty ratio controller generates the LED driving signal whose frequency is determined by the clock frequency and whose duty is determined by the dimming control signal.

Abstract: One embodiment of a compact fluorescent lamp includes a circuit assembly comprising a rectifier, a plurality of capacitors, a plurality of ICs, a plurality of inductors, a transformer for converting AC to DC, a plurality of diodes, and a PCB; a CFL electrically connected to the circuit assembly; a shade for enclosing the CFL; and a housing for mounting the circuit assembly therein. The circuit assembly is operable when voltage variation is between 2.5 and 21 V. Further, the lamp can operate in one of three different power sources (e.g., DC power supply, electronic transformer, and electrical transformer).

Abstract: A driving method of a light-emitting diode (LED) adapted to a driving apparatus is provided. The driving method includes receiving a dimming signal, detecting whether the driving apparatus performs dimming, and if the driving apparatus performs dimming, determining whether a duty cycle of the dimming signal is smaller than a predetermined value. When the duty cycle of the dimming signal is not smaller than the predetermined value, respective current magnitudes of a plurality of driving currents are regulated according to the dimming signal, and each of the driving currents is output for a full time of a period. Conversely, when the duty cycle of the dimming signal is smaller than the predetermined value, each of the driving currents is output for a partial time of a period. A driving apparatus employing the driving method is also provided.

Abstract: Methods of calibrating a lighting panel including a plurality of segments, each of said segments configured to emit a first color light and a second color light in response to pulse width modulation control signals having respective duty cycles include determining an average segment luminance for the lighting panel, determining a luminance variation of each segment to the average segment luminance, comparing the luminance variation of each segment to a threshold, and adjusting the duty cycle of at least one color of at least one segment to reduce the luminance variation in response to the luminance variation of a segment exceeding the threshold. Calibration systems are also disclosed.

Abstract: This invention relates to a kind of dimmable energy-saving lamp with remote control and buttons dimming feature comprising: a power supply module (1), one end of which being connected to municipal power supply via the button-dimming switch (K), another end of which being connected to different parts of the whole circuit including the SCM control module (2), an SCM control module (2), the output end of which being connected to the dimming control module (3), the signal output end of said dimming control module (3) being connected to the signal input end of the energy-saving lamp tube as well as the energy-saving lamp tube as the illuminating component; the invention further features: a remote-control transmitting module (5) for transmitting wireless signals at least including dimming signals; a remote-control receiving module (6) for receiving wireless signals at least including dimming signals, the output end of said remote-control receiving module (6) being connected to an input end of said SCM control modul

Abstract: A circuit arrangement includes a first light emitting diode and a second light emitting diode emitting light of different colors arranged adjacent to each other for additive color mixing. A first and second controllable current sources are connected to the first and second light emitting diode, respectively, such that the load currents of the light emitting diodes depend on respective control signals received by the current sources. First and second sigma-delta modulators are connected to the first and second light emitting diodes, respectively, and provide bit-streams as control signals to the current sources. The mean value of each bit-stream corresponds to the value of an input signal of the respective sigma-delta modulator.

Abstract: A driving device of a light emitting unit is provided. The driving device includes a driving circuit, a switch, a capacitor, and a compensation circuit. The driving circuit has a control terminal and a driving terminal connected to the light emitting unit. The driving circuit determines a driving current according to the voltage on the control terminal. The switch has a first end for receiving a data voltage, a second end connected to the light emitting unit, and a control end for receiving a scan voltage. The capacitor has a first end connected to the control terminal of the driving circuit and a second end connected to the second end of the switch. The compensation circuit has an output terminal connected to the first end of the capacitor. The compensation circuit supplies a reset voltage to the first end of the capacitor when the switch is turned on.

Abstract: The present invention relates to a protection circuit for an alternating current light emitting diode which mainly comprises light emitting diodes placed in series and parallel with loads in a light emitting diode lamp device. When one of the light emitting diodes has been damaged, the current flows through the load in parallel with the light emitting diode and flows to the next light emitting diode. Only the damaged light emitting diode is off to keep from causing an open circuit in the overall circuitry and to prevent the overall lamp device from turning off and not emitting light. In addition to the device being easier to use, finding the damaged light emitting diode for replacement is faster, easier and more convenient when repairing the damaged light emitting diode, thereby greatly enhancing the usefulness and practicability of the protection circuit for an alternating current light emitting diode.

Abstract: A klystron has a hollow beam electron gun that has a circular planar electron emitting surface. A hollow electron beam is directed from the electron gun through a plurality of drift tubes, resonant chambers and magnetic fields to a collector. The hollow electron beam does not experience significant radial movement and can operate at a lower beam voltage which reduces the required length of the RF interaction circuit and lowers the risks of RF arcing.

Abstract: A lighting apparatus for retrofitting an existing luminaire includes a plurality of light emitting diodes (LED) of similar or differing wavelengths arranged and configured in at least one light bar array, a heat sink module thermally coupled to the at least one light bar array, an electronic power module electrically coupled to the at least one light bar array, and a plate coupled to the at least one light bar array, electronic power module and the heat sink module, the plate arranged and configured for coupling to the luminaire to provide quick and easy installation and replacement of the at least one light bar array, heat sink module and electronic power module into and from the luminaire.

Abstract: A tubeless light-emitting diode (LED) based lighting device includes at least one base, at least one LED lighting module, and at least one control circuit. The base includes a heat dissipation body. The LED lighting module is mounted to the base so that the base provides the LED lighting module with the functions of retention and heat dissipation. The control circuit is mounted to the base and is electrically connected to power wiring of the LED lighting module for ON/OFF switching of the LED lighting module and supplying of operation power. As such, a tubeless lighting device that emits light in a power saving manner and is constructed in a volume reduced manner is provided.

Abstract: A light-emitting diode (LED) driver circuit is provided, which includes a transistor, a current regulator, a release diode, and a voltage clamping device. The transistor is coupled in series with an LED string. The LED string is coupled between the transistor and a bus voltage. The current regulator is coupled to the transistor for regulating the current through the transistor and the LED string to a predetermined current. The release diode has an anode coupled between the LED string and the transistor. The voltage clamping device is coupled to the cathode of the release diode for clamping the voltage level at the cathode of the release diode to a predetermined voltage. The voltage clamping device protects the transistor from breakdown when the transistor is turned off for dimming control.

Abstract: A light-emitting device capable of being powered by an AC power supply or an unregulated DC power supply is disclosed. The light-emitting device, in an aspect, is coupled to a controller, a light-emitting diode (“LED”) array, and a power supply, wherein the power supply can be an AC power source or an unregulated DC power source. While the power supply provides electrical power, the controller generates various LED control signals in response to power fluctuation of the electrical power. The LED array allows at least a portion of LEDs to be activated in accordance with the logic states of the LED control signals.

Abstract: A LED control circuit and method generate a high frequency clock signal with a fixed duty for a LED driver, to supply a switching current to drive a LED to emit light flashing at a modulated high frequency and with a fixed duty. By controlling the flashing LED light within certain flashing frequency range, the circuit and method allow a LED light source for expelling, confusing or trapping insects but serving only an illuminative or decorative purpose to human eyes, due to the difference between human beings and insects in visual perception of flashing frequencies.

Abstract: A backlight driving system comprises a first inverter circuit, a second inverter circuit, a pulse width modulation (PWM) controller, a frequency regulator and a switch circuit. The pulse width modulation (PWM) controller generates an illumination signal to control the first and second inverter circuits to illuminate first and second backlight units in response to a first enable signal, and generates a maintaining signal to control the first and second inverter circuits to maintain stable lighting of the first and second backlight units in response to a first feedback signal. The frequency regulator controls the PWM controller to generate the illumination signal and the maintaining signal in response to a second enable signal and a second feedback signal, respectively. The switch circuit connects the PWM controller to the second inverter circuit in response to the second enable signal.

Abstract: An LED illumination system includes a control circuit having a timing unit, a control unit, a PWM signal generating unit and a micro-programmed control unit (MCU). The timing unit divides an operating period of an LED lamp into different time segments, and outputs clock signals. The control unit outputs different controlling signals corresponding to the clock signals to the PWM signal generating unit, which in turn generates different PWM signals with different duty cycles. A constant current circuit electrically connects the control circuit and outputs different electric currents to make the LED lamp emit light having different light intensities at the different time segments. The MCU is at an outside of the LED lamp and sets a program to control the timing unit, the control unit and the PWM signal generating unit.

Abstract: To provide a light emitting device without nonuniformity of luminance, a correcting circuit for correcting a video signal supplied to each pixel to a light emitting device. The correcting circuit is stored with data of a dispersion of a characteristic of a driving TFT among pixels and data of a change over time of luminance of a light emitting element. Further, by correcting a video signal inputted to the light emitting device in conformity with a characteristic of the driving TFT of each pixel and a degree of a deterioration of the light emitting element based on the over-described two data, nonuniformity of luminance caused by a deterioration of an electroluminescent layer and nonuniformity of luminance caused by dispersion of a characteristic of the driving TFT are restrained.

Abstract: An optical transmitter includes a light-emitting device and an optical modulator that modulates light output from the light-emitting device by using an input signal. The optical transmitter includes a drive current switching controller that performs an ON/OFF switching control of a drive current of the light-emitting device, by using an ON/OFF signal as an input that controls ON/OFF of an optical output of the light-emitting device, in response to a switching of the ON/OFF signal. The optical transmitter also includes a drive current adjusting and generating unit that detects an ambient temperature, and generates a drive current that is adjusted according to the ambient temperature detected thereby. The drive current switching controller includes a differential circuit that is supplied a drive current that is generated by the drive current adjusting and generating unit and controls the drive current that is output to the light-emitting device, according to the ON/OFF signal.