460 results about "High-intensity discharge lamp" patented technology

An electronic ballast for high intensity gas discharge lamps where the wave form of the lamp current is square wave providing acoustic resonance and flickering free operation. The circuit, having high efficiency, operates in a wide temperature range providing ideal ballast curve and reliable ignition for the lamps. Furthermore, significant energy saving can be achieved by its externally controlled built in dimming capability.

A ballast circuit for a high intensity discharge lamp includes a boost converter, responsive to a dc input voltage, for providing a boosted dc output voltage; a boost controller, responsive to the boosted dc output voltage, for driving the boost converter to maintain the boosted output voltage at a predetermined level; a buck converter, responsive to the boosted dc output voltage, for providing a reduced dc output voltage; and a buck controller, responsive to the reduced output voltage, for driving the buck converter to operate the discharge lamp in a transition mode and maintaining the reduced dc output voltage at a preselected level for operating the discharge lamp in a steady state mode.

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.

An electronic ballast for a high intensity discharge lamp (HID) includes a power converters, a controller, and a lamp power switch. In the power converter, an input DC voltage is converted into a ballast output power for lighting the HID lamp. The controller has a function to control the power converter and change the ballast output power. The lamp power switch detects a lamp output parameter indicated after the HID lamp starts discharge, identifies a lamp power of the HID lamp according to the lamp output parameter, and gives an identification signal indicating the lamp power. In response to this identification signal, the power converter outputs the ballast output power which matches with the lamp power identified.

A means of ballasting for high intensity discharge (HID) lamps, wherein the necessary lamp striking voltage, warm-up current and steady state running current may all be controlled using only two power switching transistors 9,10 operating in two discrete modes. A further feature provides a means of lamp power control over a range of lamp voltages such that the lamp power input remains substantially constant throughout the ageing of the lamp 19. The use of this means of ballasting HID lamps can offer major cost benefits, lower circuit complexity, longer lamp life and colour maintenance and increased flexibility of the wiring installation and lamp position relative to the ballasting and striking means.

An electronic ballast for driving a high intensity discharge (HID) lamp is provided. The electronic ballast includes a voltage boost stage for receiving a DC input voltage and outputting a boosted DC output voltage with a controlled current. It further includes a switching stage for converting the boosted DC output voltage to a switched AC voltage capable of driving the HID lamp. An integrated circuit (IC) is coupled to the voltage boost stage and the switching stage for controlling both. The IC includes a lamp power control circuit comprising a sensing circuit for sensing an output current from the switching stage and the boosted DC output voltage, a current control loop which controls the lamp power if the lamp current is at a maximum level and a power control loop which controls the lamp power if the lamp current is below a maximum level. The IC also includes a controller unit interface and provides an ignition mode and a regular operation mode.

A high-intensity discharge lamp connected to a lighting device has various superior emission properties such as efficiency. The discharge lamp includes a translucent ceramic discharge vessel, in which a pair of electrodes and a discharge medium are inserted. The lamp further includes an outer jacket, in which the arc tube is disposed, and a pair of feeder members. The discharge medium has metal halides including those of Na, Tl and Tm or Na, Tl, In and Tm, and the ratio (MTm / M) of the weight of the gross sealed mass M of the metal halides to the filled mass MTm of the Tm halide is about 0.4<=MTm / M<=0.9. The deviation in chromaticity (d.u.v.) on the x-y chromaticity coordinates (CIE 1931) for the overall operating position during the life of the lamp is within the range of about -0.006 to +0.010.

A ballast controller integrated circuit which executes a specific set of instructions via an integrated state diagram architecture to control a fluorescent lamp or high intensity discharge lamp and protect the ballast. The state diagram architecture controls powering up and down of the IC and the half-bridge circuit driven by the IC, preheating and striking of the lamp, running of the lamp, sensing for numerous possible fault conditions, and recovering from these fault conditions based on the normal maintenance of a lamp, while requiring fewer internal and external components than previous electronic ballasts.

The present invention provides an electronic ballast for a high intensity discharge lamp such as a metal halide lamp. The ballast includes an inverter and a resonant circuit with an ignition capacitor between the resonant circuit and the lamp. The ignition capacitor serves to provide the necessary start-up energy and also serves to provide a low impedance discharge path. A single ignition capacitor may be sufficient, but if a long cable is used to connect the lamp to the ballast, then two ignition capacitors in parallel at opposite ends of the cable may be used. The ballast further provides means for monitoring and controlling lamp power by monitoring a nominally constant dc link voltage, and means for detecting short-circuit and open circuit conditions. A retrial mechanism is provided in the event of the lamp failing to ignite that includes a temporary disabling of the inverter in order to keep the rms lamp voltage low.

The present invention relates to a garage light assembly having a housing with a lamp mounting surface wherein a main high intensity discharge lamp and an auxiliary circular high output fluorescent lamp are mounted. The auxiliary lamp is mounted centrally within the assembly and above the light emitting portion of the high intensity discharge lamp so that the light pattern emitted from the auxiliary lamp is symmetrical and the auxiliary lamp does not shadow the light emitted from the high intensity discharge lamp.

The present high-load and high-intensity discharge lamp includes a cathode made of a material which does not (substantially) include thorium but can be used as a cathode material of high heat load, so that a long lifetime and high stability corresponding to those of thoriated-tungsten can be realized. Specifically, the cathode is made of a metal base having a high melting point which mainly consists of tungsten and includes a coexisting substance in which an oxide of at least one kind of metal selected from lanthanum, cerium, yttrium, scandium, and gadolinium and an oxide of at least one kind of metal selected from titanium, zirconium, hafnium, niobium, and tantalum are coexistent. The conversion grain size of the coexisting substance is 15 μm or greater, and the plurality of coexisting substances are present in the metal base with a high melting point.

A circuit for controlling power to a high intensity discharge lamp is disclosed. The circuit according to one embodiment of the invention comprises a rectifier circuit coupled to receive an alternating current line voltage, and a boost / flyback converter coupled to the rectifier circuit which outputs a regulated DC bus voltage. A power control circuit also couples a feedback signal to the boost / flyback converter to regulate the power output of the boost / flyback converter. A method of controlling power to a high intensity discharge lamp is also disclosed. The method comprises steps of generating a DC voltage for the high intensity discharge lamp by way of a boost / flyback converter; monitoring the DC voltage and the current generated in the boost / flyback converter; and modifying the power output by the boost / flyback converter to regulate power based upon the voltage and the current.

There is provided a high-intensity discharge lamp lighting apparatus to be loaded with a plurality of types of high-intensity discharge lamps and connected with any one of the lamps to be lighted, and the apparatus comprises a power conversion circuit for converting power supplied from a DC power source to supply the power to a high-intensity discharge lamp and a lighting control circuit for controlling the supply power of the power conversion circuit, wherein the type of the connected high-pressure discharge lamp is determined based upon a change rate of an electric characteristic of the high-intensity discharge lamp during a specific period, and the connected high-intensity discharge lamp is lighted with a desired electric characteristic selected based upon the determination result, thereby enabling discrimination of types of rated power of the plurality of types of lamps by the same detection method and the same control method irrespective of states in starting of the lamps, and by enabling the discrimination before stable lighting of the lamp, it is possible to start the discharge lamp with little stress applied to the discharge lamp.

The present High Intensity Discharge electronic lamp ballast uses a “set of controls” that can be performed by controlling energy delivery by the “line side converter” to the “lamp side inverter”. This set of controls comprises: 1) open circuit voltage control, 2) breakdown voltage amplitude control, 3) glow-to-arc transition current control, 4) “initial arc development” current control, 5) “arc stabilization” current control, 6) lamp power control, 7) lamp dimming, 8) “lamp rectification” current control, and 9) short circuit and lamp fault protections. One of the primary advantages of this “line side converter” energy delivery control method is that it doesn't need to vary the lamp operating frequency to achieve the above-noted controls.

A means of ballasting for high intensity discharge (HID) lamps, wherein the necessary lamp striking voltage, warm-up current and steady state running current may all be controlled using only two power switching transistors 9,10 operating in two discrete modes is provided for avoiding acoustic arc resonance during the steady state running. A low frequency lamp current is generated with a frequency modulated high frequency ripple.

A compact, low cost high intensity discharge lamp ballast apparatus which can carry out normal ballasting without extinction at discharge start includes a DC-AC inverting booster circuit, a first resonance circuit, and a second resonance circuit. The DC-AC inverting booster circuit includes a DC-AC converter transformer for converting a DC voltage fed from a DC power supply to an AC voltage in response to switching on and off of FETs, boosting the voltage. The first resonance circuit includes a leakage inductance connected in series with the secondary winding of the DC-AC converter transformer, and a first resonant capacitor connected in parallel with the secondary winding. The second resonance circuit includes a metal halide lamp, an ignitor transformer for producing a voltage to start lighting of the metal halide lamp, and a second resonant capacitor.

The present invention relates to an apparatus for cosmetic skin rejuvenation treatment, comprising a continuous wave light source accommodating a high-intensity discharge lamp (104; 204; 304; 604) which has at least one predominant spectral peak between 600 and 700 nm.

A circuit for controlling power to a high intensity discharge lamp is disclosed. The circuit according to one embodiment of the invention comprises a rectifier circuit coupled to receive an alternating current line voltage, and a boost / flyback converter coupled to the rectifier circuit which outputs a regulated DC bus voltage. A power control circuit also couples a feedback signal to the boost / flyback converter to regulate the power output of the boost / flyback converter. A method of controlling power to a high intensity discharge lamp is also disclosed. The method comprises steps of generating a DC voltage for the high intensity discharge lamp by way of a boost / flyback converter; monitoring the DC voltage and the current generated in the boost / flyback converter; and modifying the power output by the boost / flyback converter to regulate power based upon the voltage and the current.

Power source systems implementing methods for reducing vertical segregation (color mixing) in a long and thin high intensity discharge lamp are disclosed. Each system provides a current frequency signal to the lamp that excites an azimuthal acoustic and longitudinal acoustic combination mode of the lamp whereby color mixing within the lamp can be achieved. Each system further adjusts the current frequency signal as needed to stabilize color mixing within the lamp.

An apparatus is disclosed for automatic light dimming of electronic and magnetic ballasts used for fluorescent or high intensity discharge lamps. A variable capacitant's limiting current is added in the lamps which provides lighting intensity controls without changing the ballast's operation frequency. Several capacitors are placed in line with a terminal for the lamp. The capacitor's switching capability is used to change the current received by the lamp. The amount of voltage can be controlled by either varying the supply voltage, or with an elimination sensor, or by manual potentiometer control.

There is provided a high-intensity discharge lamp lighting apparatus to be loaded with a plurality of types of high-intensity discharge lamps and connected with any one of the lamps to be lighted, and the apparatus comprises a power conversion circuit for converting power supplied from a DC power source to supply the power to a high-intensity discharge lamp and a lighting control circuit for controlling the supply power of the power conversion circuit, wherein the type of the connected high-pressure discharge lamp is determined based upon a change rate of an electric characteristic of the high-intensity discharge lamp during a specific period, and the connected high-intensity discharge lamp is lighted with a desired electric characteristic selected based upon the determination result, thereby enabling discrimination of types of rated power of the plurality of types of lamps by the same detection method and the same control method irrespective of states in starting of the lamps, and by enabling the discrimination before stable lighting of the lamp, it is possible to start the discharge lamp with little stress applied to the discharge lamp.

A lighting system includes a high intensity discharge metal halide lamp having an arc discharge chamber with electrodes at each end and containing a fill of mercury, rare gas and metal halides, and a ballast circuit configured to supply pulsed electrical power to the lamp. The ballast circuit includes a controller configured to adjust the pulsed lamp power between a first relatively high power level at a relatively high duty cycle and a second relatively low power level at a relatively low duty cycle. The controller may be configured to adjust the pulsed lamp power between 90% duty cycle at rated lamp power and 10% duty cycle at 30% of the rated lamp power. The duty cycle of the pulsed lamp power may be controlled to maintain a substantially constant correlated color temperature (CCT) as the power level is adjusted.

A high intensity lighting system comprises a plurality of high intensity discharge lamps electrically connected to a polyphase alternator and a prime mover mechanically connected to the alternator. An inherent impedance characteristic of the alternator permits the lamps to be reliably started and energized without any separate ballast or comparable impedance element. The alternator comprises a stator having teeth extending from a backiron. The teeth consist of the alternator phases, and the coils encircle the respective teeth of each pair and are wound in opposite sense and connected in series. The machine is preferably an axial airgap device wherein the stator assembly has a magnetic core made from low loss, high frequency material. A high pole count permits the electrical device to operate at high commutating frequencies, with high efficiency, high power density and improved performance characteristics. Low-loss materials incorporated by the device include amorphous metals, nanocrystalline metals, optimized Si—Fe alloys, grain-oriented Fe-based materials or non-grain-oriented Fe-based materials.

An integrated circuit controls a power converter that includes single stage buck-boost converter and a switching full bridge that may be used to drive an HID lamp. The single stage buck-boost converter reduces the complexity and parts count of the power converter, or electronic ballast, while permitting PFC and DC bus voltage regulation under control of the integrated circuit. The integrated circuit also provides all the drive signals to operate the switching full bridge circuit to maintain constant power on the HID lamp. A wait timer provides an interval of time between restart attempts for the HID lamp to permit the lamp to cool so that high hot restart voltages are avoided. The integrated circuit simplifies the design of power converters and electronic ballasts in particular, while contributing to reducing part count, complexity and cost in conjunction with the single stage buck-boost converter.

In accordance with certain embodiments, the present technique includes a system for sealing a lamp including a thermal shield and a thermally susceptible enclosure disposed adjacent the thermal shield. The thermal shield has a first receptacle adapted to receive a first portion of the lamp. The thermally susceptible enclosure comprises a wall about a second receptacle adapted to receive a second portion of the lamp. The wall has a varying thickness in a desired sealing region between the first and second portions of the lamp.

Operation of an HID lamp may be improved by forming a glow generating recess on an exterior side the electrode. The lamp may be of standard construction with a light transmissive lamp envelope having a wall defining an enclosed volume. At least one electrode assembly is extended in a sealed fashion from the exterior of the lamp through the lamp envelope wall to be exposed at an inner end of the electrode assembly to the enclosed volume. A metal halide lamp fill is enclosed with an inert fill gas. The inner end of the electrode is formed with a recess having a least spanning dimension S and a recess depth of D where S is greater the electron ionization mean free path but less than twice the cathode fall plus negative glow distances, throughout the glow discharge phase of starting, for the chosen fill gas composition and pressure (cold).