Abstract: An adaptive sliding-frequency triggering ignition method for electronic ballast of high pressure gas discharge lamp includes the steps of: measuring an accurate value of free oscillation frequency of the ballast load loop by using a single-chip before sliding-frequency triggering ignition, implementing safe and reliable sliding-frequency triggering ignition after calculating the initial frequency and ending frequency of sliding-frequency triggering ignition according to the accurate value. The method can safely and reliably finish sliding-frequency triggering ignition course, thus improving the parameters such as the quality, life of the high pressure gas discharge lamp electronic ballast.

Abstract: An LED package containing integrated circuitry for matching a power source voltage to the LED operating voltage, LEDs containing such integrated circuitry, systems containing such packages, and methods for matching the source and operating voltages are described. The integrated circuitry typically contains a power converter and a constant current circuit. The LED package may also contain other active or passive components such as pin-outs for integrated or external components, a transformer and rectifier, or a rectifier circuit. External components can include control systems for regulating the LED current level or the properties of light emitted by the LED. Integrating the power supply and current control components into the LED can provide for fabrication of relatively small LEDs using fewer and less device-specific components.

Abstract: The lighting apparatus in accordance with the present invention includes a dimming control unit configured to control, in accordance with a dimming ratio, a light source including a plurality of light emitting elements designed to emit light in response to DC power. The dimming control unit is configured to, when the dimming ratio falls within a first dimming range, vary supply power to the light source in accordance with the dimming ratio. The dimming control unit is configured to, when the dimming ratio falls within a second dimming range different from the first dimming range, vary, in accordance with the dimming ratio, a lighting number defined as the number of the light emitting elements to be lit.

Abstract: A vehicular lamp has a light source unit having an LED and an optical element that performs light distribution control for directing light from the LED in a predetermined direction, a heat sink to which the light source unit is attached, and a lamp chamber in which the light source unit is disposed. The LED is an LED module formed by installing an LED chip on a power supply circuit board. The LED module is installed on a circuit board installation portion of the heat sink, and an attachment, which has a frame shape a size larger than the LED module and has a circuit board retaining portion at a center open portion of the attachment, is attached and fixed to the heat sink by a fixing member, whereby the LED module is held between the attachment and the circuit board installation portion.

Abstract: A light source control device controlling a light source that emits light corresponding to supplied current and a color wheel having a plurality of color segments that converts the light emitted from the light source, the light source control device includes: a current generation circuit, which supplies current to the light source, based on a control signal for controlling an amount of the light of the light source; and a control circuit unit, which stores a plurality of modulation factors corresponding to the plurality of color segments and has a plurality of calculation units corresponding to the plurality of color segments, and which operates the calculation unit corresponding to the segment in synchronization with each segment to thus calculate control information of the control signal.

Abstract: Apparatus and associated methods reduce harmonic distortion of a excitation current by diverting the excitation current substantially away from a number of LEDs arranged in a series circuit until the current or its associated periodic excitation voltage reaches a predetermined threshold level, and ceasing the current diversion while the excitation current or voltage is substantially above the predetermined threshold level. In an illustrative embodiment, a rectifier may receive an AC (e.g., sinusoidal) voltage and deliver unidirectional current to a string of series-connected LEDs. An effective turn-on threshold voltage of the diode string may be reduced by diverting current around at least one of the diodes in the string while the AC voltage is below a predetermined level. In various examples, selective current diversion within the LED string may extend the input current conduction angle and thereby substantially reduce harmonic distortion for AC LED lighting systems.

Abstract: A light emitting element drive device includes an electric conduction switch that is provided along a power input line, a voltage detection unit that detects a power source voltage containing a noise component when the electric power is supplied to the power input line, a conversion processing unit that converts the detected power source voltage containing the noise component to a digital value, a data generation unit that generates data of a predetermined number of bits, and a control unit that turns on the electric conduction switch. The control unit determines a delay time based on the predetermined number of bits. The delay time corresponds to a time between supplying the electric power to the power input line and turning on the electric conduction switch. The control unit turns on the electric conduction switch after the delay time passes. Thus, an excessive rush current is prevented.

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: Reduction of luminance dispersion of a plurality of light-emitting panels combined into one light-emitting device is achieved by the use of a new light-emitting device which has a photosensor, a plurality of light-emitting panels, DC/DC converters connected to their respective light-emitting panels, and a control circuit configured to control output currents of the DC/DC converters in accordance with illuminance data acquired with the photosensor. The control circuit successively turns on the plurality of light-emitting panels, and controls the output currents of the DC/DC converters in accordance with differences of the illuminance data acquired with the photosensor when the light-emitting panels are turned on.

Abstract: LED dimming control circuit and method compensate LED current or LED average current by LED characteristics to improve dimming efficiency and performance. LED characteristic related look-up tables are stored to provide compensation values, and input LED current setting information is compensated by the compensation values to generate corrected LED current setting information for determining LED brightness.

Abstract: A pixel, a display device using the pixel and a method of driving the display device are provided. The pixel may include an organic light emitting diode, a driving circuit for generating and transmitting driving current depending on data signals to the organic light emitting diode, and at least one switch connected between a power wire for applying a first voltage to the organic light emitting diode and a data line for transmitting the data signals. The at least one switch may include a compensating circuit for electronically connecting the power wire to the data line for a predetermined period to transmit the first voltage through the data line.

Abstract: A high gate voltage generator and a display module are provided. The high gate voltage generator includes a pulse width modulation (PWM) signal generating circuit, a boost circuit, and an amplifier circuit. The PWM signal generating circuit is used for outputting a PWM signal. The boost circuit is electrically connected to the PWM signal generating circuit and used for receiving an input voltage to boost the input voltage according to the PWM signal and then outputting a power voltage. The amplifier circuit is electrically connected to the boost circuit and used for receiving a reference voltage to amplify the power voltage and then outputting a high gate voltage. The reference voltage is greater than the high gate voltage and is provided by a backlight module electrically connected to the amplifier circuit.

Abstract: An anti-collision aircraft light comprises at least one LED and a control unit for operating the at least one LED in a pulsed manner. In this anti-collision aircraft light, the control unit comprises an ambient temperature sensor for sensing the ambient temperature and an adjustable current control for setting an LED operating current depending on the sensed ambient temperature. The control unit further includes a light intensity sensor for sensing the intensity of the light emitted from the at least one LED, an integrator connected to the light sensor for integrating the sensed light intensity, and a comparator for comparing the integrated light intensity to a threshold value. The operating current for the at least one LED is interrupted as soon as the integrated light intensity is equal to the threshold value.

Abstract: A projector that outputs a first picture and a second picture alternately, wherein a control section performs first control and second control, controls a discharge lamp driving section. In the first control and the second control, the absolute value of a drive current is relatively small in a first period and relatively large in a second period. In the first control, the energy provided to a first electrode in the second period is greater than the energy provided to the second electrode in the second period. In the second control, the energy provided to the second electrode in the second period is greater than the energy provided to the first electrode in the second period.

Abstract: Electronic devices require correct power in order to operate correctly. Receiving an incorrect power signal could potentially result in immediate and/or long term harm to the electronic device and/or catastrophic conditions. Certain devices, such as programmable logic controller (“PLC”) modules, may provide variable power to electronic devices, such as field devices comprising sensors and/or actuators. The present inventors have recognized that deciphering between AC and DC input signals before coupling electronic devices to such power sources may advantageously avoid harmful and/or catastrophic conditions. Aspects of the present invention provide an electronic circuit for deciphering between an AC and a DC input signal. Systems and methods are also described.

Abstract: A projector that outputs a first image and a second image alternately while performing switching between the first image and the second image, includes: a discharge lamp driving section that supplies, to a discharge lamp, a drive current that drives the discharge lamp; a state detecting section that detects a deteriorating state of the discharge lamp; and a control section that controls the discharge lamp driving section, wherein the control section controls the discharge lamp driving section so that the absolute value of the drive current becomes relatively small in a first period and relatively large in a second period and controls the discharge lamp driving section so that the ratio of the absolute value of the drive current in the second period to the absolute value of the drive current in the first period is increased with the progress of the deteriorating state.

Abstract: A passive anti-arcing protection components for electronic ballasts of fluorescent lamps. This protection component is a bridge-rectifier-resistor-capacitor network, containing at least a diode, a resistor, and a capacitor. The component's circuitry is electrically connected to the ballast at the lamp side, acting as a low-resistance redirection path for any sudden change in energy. When an arcing condition is about to occur, this protection circuitry absorbs the spark energy, ceasing the arcing condition.

Abstract: A plant illumination apparatus includes a light source module including a first light source and a second light source generating lights having different wavelengths, an environment-detecting module detecting an external environment to obtain a real-time environment parameter, and a control module connected to the light source module and the environment-detecting module. The control module includes a processor unit and a storage unit storing a database of plant growing environment parameters. The processor unit loads at least one preset growing environment parameter corresponding to a plant growth timing from the database of plant growing environment parameters, and compares the preset growing environment parameter with the real-time environment parameter to output at least one comparison result. The processor unit adjusts the first light source and the second light source according to the comparison result, so that an adjusted environment parameter matches the preset growing environment parameter.

Abstract: The present invention provides an LED light string color mixing and synchronization circuit, in which each of LED lights composed of an LED light string includes two input terminals and two output terminals. The two input terminals are respectively an input terminal of reverse parallel connection of any two of three primary light-emitting chips of R, G, B and an anode input terminal of the remaining primary light-emitting chip and the two output terminals are respectively an output terminal of reverse parallel connection of any two of three primary light-emitting chips of R, G, B and a cathode output terminal of the remaining primary light-emitting chip. Thus, each of the LED lights of the LED light string is connected in a two-input two-output series connection to form a light string arrangement with two terminals thereof in combination with four electrical wires.

Abstract: A sensing device transmits wireless signals when an error between at least one sampled parameter value and at least one predicted parameter value is too great, such that the sensing device transmits wireless signals to a load control device using a variable transmission rate that is dependent upon the amount of change in a value of the parameter. The sensing device uses the one or more estimators to determine the predicted parameter value, and may transmit the estimators to the load control device if the error is too great. The load control device uses the estimators to determine at least one estimated parameter value and controls the electrical load in response to the estimated parameter value. The sensing device may comprise, for example, a daylight sensor for measuring a total light intensity in the space around the sensor or a temperature sensor for measuring a temperature around the sensor.