Abstract: A winding device includes a core, a wire winding provided in the core, and a heat conductive material. The heat conductive material is provided around an outer surface of the wire winding to contact the wire winding and the core via the heat conductive material.

Abstract: A circuit arrangement and control thereof for igniting a high intensity discharge lamp, for reducing current stresses imposed on semiconductor devices during a polarity transition of a lamp voltage or lamp current, and for maintaining a parasitic current within an envelope of a square wave lamp current. A high frequency ignition voltage is only applied to the lamp during a starting operation. After the lamp breaks down in the starting operation, an imbalanced high frequency current flows through the lamp to assist a glow-to-arc transition. The high discharge current of the buck filter capacitor that is generally applied to the semiconductor devices during the polarity transition of the lamp voltage or lamp current, due to lamp extinguishing, is reduced. The lamp current is maintained as a low frequency square wave. Any spikes that may occur at the polarity transition of the lamp voltage or lamp current are superimposed on the lamp current within the envelope of the low frequency square wave lamp current.

Abstract: A circuit arrangement and control thereof for igniting a high intensity discharge (HID) lamp, for reducing the variation of the resonant ignition voltage under the parasitic capacitive loading condition, and for increased circuit stability. The high frequency ignition voltage is only applied to the lamp during an ignition phase. The variation of the magnitude of the resonant ignition voltage with respect to the parasitic capacitance at the lamp leads is minimized by inserting a damping resistor in series with the ignition resonant capacitor. In a normal operation after ignition, the charge and/or discharge current of the ignition resonant capacitor is bypassed through a bypass device instead of flowing through a current sense resistor, so that only a chopper current flows through a sensor by paralleling a relatively high impedance resistor with the sensor.

Abstract: A circuit arrangement and control thereof for igniting a high intensity discharge (HID) lamp, for reducing the variation of the resonant ignition voltage under the parasitic capacitive loading condition, and for increased circuit stability. The high frequency ignition voltage is only applied to the lamp during an ignition phase. The variation of the magnitude of the resonant ignition voltage with respect to the parasitic capacitance at the lamp leads is minimized by inserting a damping resistor in series with the ignition resonant capacitor. In a normal operation after ignition, the charge and/or discharge current of the ignition resonant capacitor is bypassed through a bypass device instead of flowing through a current sense resistor, so that only a chopper current flows through a sensor by paralleling a relatively high impedance resistor with the sensor.

Abstract: A high intensity discharge (HID) lamp driving circuit. The HID lamp driving circuit includes a first pair of switching devices connected to a high frequency resonant filter, and a second pair of switching devices connected to a ripple reducing filter. A HID lamp is connected between the first pair of switching devices and second pair of switching devices, with a dc power supply being connected to the first pair of switching devices and the second pair of switching devices. The first pair of switching devices and the second pair of switching devices are connected to a common ground with the dc power supply. The lamp driving circuit operates in a half bridge topology during a start-up operation mode of the lamp, and operates in a full-bridge topology during a steady-state operation mode of the lamp. The HID lamp driving circuit is operated in an active zero current switching scheme.

Abstract: A circuit to start an HID lamp in a high-frequency start mode and, after starting, to operate the lamp in a low-frequency operating mode is controlled, during the high-frequency start mode, to drive the lamps with a voltage that includes a high-frequency component to ignite the lamp and a unipolar or bipolar offset component to keep the lamp ignited during a transition from the high-frequency start mode to the low-frequency operating mode.

Abstract: A discharge lamp adapted to operate on DC current and being equivalent to an AC-operated ceramic metal halide lamp in different operating positions. The lamp comprises a ceramic arc tube with a fill of mercury, rare gas and metal halides. The arc tube is sealed with an anode and a cathode and has at least one metal heat shield on the cathode side of the ceramic DC metal halide arc tube to achieve operation of the lamp with universal orientation. Each of the two electrodes sealed into the arc tube are different, the anode being formed of tungsten with a ball shaped tip and the cathode being formed of a thoriated tungsten rod and a wound coil of the rod.

Abstract: A circuit arrangement and method thereof for operating high intensity discharge (HID) lamps with a lower frequency rectangular current waveform, in which the frequency of the higher frequency ripple superimposed on the lower frequency rectangular current is modulated by a pseudo-random noise signal. The pseudo-random noise may be generated by a feedback shift register. The feedback shift register may incorporate run length interrupt logic to address PWM frequency stagnation by reducing the longest run length or lengths of the feedback shift register. The feedback shift register may also or alternatively include an RC low pass analog filter to address PWM frequency stagnation. The center frequency and frequency band of the pseudo-randomly generated noise may be adjustable.

Abstract: The present invention is directed to a metal hydrides lamp and a fill for such a lamp. The lamp chamber includes a fill of at least one metal, a buffer gas, and hydrogen and/or deuterium. When energy is provided to the fill, metal combines with the hydrogen and/or deuterium to form a molecule at an excited energy level which emits visible light when the molecule moves to a ground state energy level. The lamp may be an electrode lamp, an electrodeless lamp, a microwave lamp, or any other power source capable of imparting energy into a fill contained within a lamp chamber.

Abstract: An electrodeless fluorescent lamp and fixture which operates at the frequency range of 50-1000 KHz and power from 20 to 200 W is disclosed. The lamp includes a bulbous envelope (1) filled with rare gas and metal vapor and a reentrant cavity (5). The inner walls of the envelope are coated with phosphor (2) and a protective coating (3). An induction coil (9), made from multiple strands of wire having very low resistance at frequencies below 1000 KHz, together with a ferrite core (10), having high permeability and low power losses, generates an inductively-coupled plasma in the envelope volume. The plasma generates visible and UV radiation that is converted into visible light by the phosphor coated on the envelope walls. A metallic cylinder (13), placed inside the ferrite core (10), removes the heat generated by the plasma from the coil and ferrite core and redirects the heat to the lamp base and thence to the lamp fixture.

Abstract: An electronic ballast circuit includes an input section which rectifies, power factor corrects and filters an AC input voltage to provide a rectified signal. The electronic ballast circuit also includes an inverter section which receives the rectified voltage and switches the rectified voltage to provide an AC signal to a resonant load circuit. The input section includes a resonant tank circuit which provides a high frequency current to the inverter to soft switch the switches within the inverter. In the input section, an inductor is placed on the AC side of a diode bridge rectifier advantageously allowing the removal of several prior art ballast circuit components since placing this portion of the power factor correction (PFC) circuit within the input circuit on the AC side of the diode bridge rectifier allows the bridge rectifier to perform both the rectification and current blocking functions.

Abstract: A circuit arrangement and control thereof for igniting a high intensity discharge (HID) lamp, for reducing the high frequency ripple superimposed on the low frequency rectangular waveform lamp current after ignition, and for increased circuit efficiency. The high frequency ignition voltage is only applied to the lamp during ignition phase and is mainly generated by the second stage of the low pass (LP) filter. The first stage of the LP filter whose resonant frequency is below the second stage further attenuates the high frequency ripple current through the lamp in normal operation. The resulting lamp current is a low frequency rectangular wave with less than 10% high frequency ripple. Acoustic resonance is avoided. The inductor in the first stage of LP filter is operated in discontinuous current mode. Doing so, the active switches are in zero current switching (ZCS) to maximize the circuit efficiency.

Abstract: A discharge lamp (10) based on microwave excitable sulfur gas with enhanced red component of visible light emission from the lamp as a whole, the lamp having an arc discharge tube (18) light source, microwave excitation means (M) and an outer inert zone around the arc discharge tube having a layer of phosphor (16) selected to absorb a portion of blue-green spectral component of the arc discharge tube emission and emit a concentrated red region of spectral range of light to combine with non-red spectral components of light passing through the phosphor. The phosphor can be essentially homogeneous material or may comprise a mixture of distinct phosphor types and/or a multi-layered array.

Abstract: A power factor correction circuit, usable with, for example, a switching power supply of a discharge lamp. The power factor correction circuit includes a shaping system that shapes an input current of a power line during a predetermined period proximate a zero line crossing point of the input current; and a minimizing system that minimizes a pulsating of the input current.

Abstract: An electric power source device includes a power converting circuit and a load circuit (LD) for receiving an output from the power converting circuit. The power converting circuit includes a rectifier element (DB) for rectifying an input from an alternating current source (AC), a smoothing capacitor (Ce) for smoothing an output from the rectifier element (DB) with a direct current, and switching elements (Q1, Q2) for generating high frequency voltage and current in response to receipt of a voltage of the smoothing capacitor (Ce).

Abstract: A discharge lamp driving circuit includes DC voltage input connections, lamp driving connections, bridge circuitry, and control circuitry. The bridge circuitry is connected to the DC voltage input connections and to the lamp driving connections and includes circuit elements which in one mode of operation deliver a higher frequency AC voltage to the lamp driving connections and in another mode of operation deliver a lower frequency AC voltage to the lamp driving connections. The control circuitry is connected to control the bridge circuitry selectively as either a half-bridge to deliver the higher frequency AC voltage to the lamp driving connections during starting or a full-bridge to deliver only the lower frequency AC operating voltage to the lamp while the lamp is operating normally after starting. A low frequency driver and a high frequency driver are connected to drive the bridge circuitry.

Abstract: Low pressure sodium lamp color output is shifted from yellow to a fuller spectral range of visible light (white) by effective simultaneous excitation of sodium and a mercury additive. This is made possible principally by controlling the vapor constituents and the excitation arrangement.

Abstract: A fluorescent lamp (2) having at least two phosphor coatings (12) on the surface of the sealed lamp bulb, typically an inner surface. There is variable driving means which preferentially activates one phosphor and not the other phosphors, at one arrangement or setting or configuration of the driving means, while at another setting the driving means activates in addition a different or several different phosphors. Each phosphors may be a blend of phosphors and the phosphors and/or blends may be overcoated upon one another forming multiple layers or all mixed together and applied as a one layer coating on the lamp surface.

Abstract: An elongated arc tube is folded into multiple parallel legs in a close packed peripheral array about a long, thin ballast housing, the combination constituting a retrofittable incandescent bulb replacement compact flourescent having a shorter overall length and a more uniform spatial light distribution.

Abstract: Electrodeless, low pressure, fluorescent discharge lamp of high aspect ratio, with a substantially flat spiral rf coil adjacent a back face (and insulated therefrom), that emits light through a front surface or selected portions under control of internal reflective and phosphor coatings placement to afford minimum resonance trapping, high efficiency and uniform illumination of high specific intensity over a selected area of the front wall.