Abstract: An oscillator is coupled to a first side of a galvanic barrier for supplying thereto an electric supply signal. The oscillator is configured to be alternatively turned on and off as a function of a PWM drive signal applied thereto. A receiver circuit coupled to the galvanic barrier receives therefrom a PWM power control signal. A signal reconstruction circuit coupled between the receiver circuit block and the oscillator provides to the oscillator a PWM drive signal reconstructed from the PWM power control signal. The signal reconstruction circuit includes a PLL circuit coupled to the receiver circuit block and configured to lock to the PWM control signal from the receiver circuit block. A PLL loop within the PLL circuit is sensitive to the PWM drive signal applied to the oscillator. The PLL loop is configured to be opened as a result of the power supply oscillator being turned off.

Abstract: A defibrillation circuit comprising a gas discharge tube and a light source arranged to pre-energize the gas discharge tube in order to provide predictable breakdown conditions of the gas discharge tube. The gas discharge tube may be used as an overvoltage protection device for the defibrillation circuit or for certain parts of the defibrillation circuit. An overvoltage protection device for medical devices is also described. The overvoltage protection device comprises a gas discharge tube and a light source arranged to pre-energize the gas discharge tube in order to provide predictable breakdown conditions of the gas discharge tube.

Abstract: A tungsten cathode material to be used for TIG welding, plasma spraying, plasma cutting, electro-discharge machining, discharge lamps, and the like is improved; use of the radioactive element thorium is reduced; and a long life and a high performance are realized. In a tungsten cathode material, oxide particles containing an oxide or oxides of at least one selected from the group consisting of Sm, Nd, Gd, and La in a total amount of 50 vol % or more are dispersed, the oxide particles having an average particle diameter d satisfying the relationship 0<d?2.5 ?m. Given a volume fraction f (vol %) of the total amount of the oxide particles in the tungsten cathode material, 0.083?f/I holds when a current I(A) such that 0<I?40 A is applied to an electrode being made of the tungsten cathode material.

Abstract: Various embodiments provide a high-pressure discharge lamp. The high-pressure discharge lamp may include a discharge vessel; and an electrode, which is secured in one end of the discharge vessel, the electrode having a stem designed as an elongated pin-shaped body, the electrode being part of an electrode system that also comprises a lead-through, with the aid of which the end of the discharge vessel is sealed in a gas-tight manner; wherein at least the stem includes an electrically conductive ceramic boride of a metal that comprises at least lanthanum, cerium, yttrium or ytterbium, alone or in combination.

Abstract: The invention relates to a dielectric barrier discharge lamp in a coaxial double-tube arrangement, comprising an exterior electrode (6), and interior electrode (7), and an auxiliary electrode (8). The interior electrode (7) is designed as an electrically conductive layer placed inside the interior tube (3) of the double-tube arrangement. The auxiliary electrode (8) is designed, for example, as a metal tube or pipe and is also disposed inside the interior tube (3), specifically in direct contact with the layer. In this manner, the conductivity of the interior electrode (S) is improved.

Abstract: A system, in certain embodiments, includes a high intensity discharge lamp having a composite leg. The composite leg includes a plurality of leg sections coupled together in series. The plurality of leg sections includes different materials, coefficients of thermal expansion, Poisson's ratios, or elastic moduli, or a combination thereof. A method, in certain embodiments, includes enclosing a high intensity discharge within a ceramic arc envelope. The method also includes reducing thermal stresses associated with the high intensity discharge via a composite leg extending outwardly from the ceramic arc envelope. The composite leg includes a plurality of leg sections coupled together in series. The plurality of leg sections includes different materials, coefficients of thermal expansion, Poisson's ratios, or elastic moduli, or a combination thereof.

Abstract: An all-metal electron emissive structure for low-pressure lamps is disclosed. The all-metal electron emissive structure consisting of one or more metal is operable to emit electrons in response to a thermal excitation, wherein an active region of the electron emissive structure under steady state operating conditions has a temperature greater than about 1500 degree K, and wherein the cathode fall voltage in the discharge medium under steady state operating conditions is less than about 100 volts. A lamp including an envelope, an electrode including the all-metal electron emissive structure, and a medium, is also disclosed.

Abstract: A ceramic discharge vessel is described that is provided a feedthrough comprised of a molybdenum alloy containing at least 75 weight percent molybdenum and greater than 5 weight percent of nickel and at least one other alloying metal selected from copper and iron, wherein the weight ratio of the amount of nickel to the combined amount of copper and iron, Ni:(Fe,Cu), in the alloy is in the range of 1:1 to 9:1. The thermal expansion coefficient of the alloy is sufficiently matched to that of the ceramic so that the feedthrough may be sealed to the discharge vessel without causing cracking. Preferably, the feedthrough is directly sealed to the ceramic discharge vessel without the use of an intermediate frit material.

Abstract: A luminous discharge display device having two distinct, independent discharge chambers, stacked vertically; of substantially flat circular shape containing inert gas mixtures, and a central electrode coupled to a power supply which provides ionizing means for the gas. The device utilizes two grooves formed into defining members of the discharge chambers to increase the capacitance along their length due to the inverse relationship between dielectric width and capacitance. Two electrode assemblies are biased out of phase with respect to the main electrode further increasing the capacitance and converging the luminous discharge at that specific point and are fitted into the circular grooves. A clock mechanism moves the electrode assemblies along their respective grooves thus creating a controlled motion of the luminous glowing plasma.

Abstract: An electrodeless HID lamp having a quartz arc tube having a gas fill contained therein, is energized to a discharge state upon the introduction of a high frequency RF current in close proximity thereto, also includes a starting aid stem which extends from the arc tube. An outer jacket surrounds the arc tube and a portion of the starting aid stem. The outer jacket is pinch sealed at the end from which the starting aid stem extends. This pinch sealing results in the formation of a sealed space between the outer jacket and the arc tube and further allows that, by the gripping of the starting aid stem at the pinch seal region, the arc tube is supported in a fixed non-contacting position within the outer jacket. A sealant material can be applied around the starting aid stem at the pinch seal region to prevent leakage of the sealed space formed within the outer jacket.

Abstract: A gas discharge apparatus includes a discharge chamber including a transparent dome portion and an electrode-including base portion, which together enclose an ionizable gas. A cup-shaped base member is affixed at its periphery to the edge of the base portion of the discharge chamber. A power supply and discharge excitation network is disposed within the interior of the base portion. The power supply and discharge network include a pair of terminals. An oscillator and associated step-up output transformer powered from the terminals is positioned between the terminals and the discharge chamber. A field shield including a conductive sheet member is positioned between the terminals and the discharge chamber. The field shield is adapted to be electrically coupled to the electrode so that discharge-supporting electric fields may be established in the discharge chamber between the electrode and through the dome portion of that chamber to an effective ground electrode exterior to the chamber.

Abstract: A gas containing envelope in the form of a double walled cylinder is closed at one end and open at its other end, with the double walls of the cylinder defining an enclosed gas discharge area. The double walls of the cylinder are made of a transparent dielectric material such as glass. The gas discharge area formed between the double walls is filled with an ionizable gas, and an electrode is disposed adjacent to or within the gas discharge area between the cylinder walls at the closed end of the envelope cylinder. A ground potential reference point is provided outside the double walled cylinder, and a power supply is provided to couple an a.c. electrical signal between the electrode and the ground potential reference point for producing visible electrical discharges in said gas discharge area.

Abstract: A gas discharge apparatus includes a discharge chamber including a transparent dome portion and an electrode-including base portion, which together enclose an ionizable gas. A cup-shaped base member is affixed at its periphery to the edge of the base portion of the discharge chamber. A power supply and discharge excitation network is disposed within the interior of the base portion. The power supply and discharge network include a pair of terminals. An oscillator and associated step-up output transformer powered from the terminals is positioned between the terminals and the discharge chamber. A field shield including a conductive sheet member is positioned between the terminals and the discharge chamber. The field shield is adapted to be electrically coupled to the electrode so that discharge-supporting electric fields may be established in the discharge chamber between the electrode and through the dome portion of that chamber to an effective ground electrode exterior to the chamber.

Abstract: The invention relates to a low-pressure mercury vapor discharge lamp having a tubular discharge vessel which is sealed in a vacuum-tight manner, a filamentary body, consisting for example of glass wool, which is thinly distributed over the volume of the discharge vessel being provided near the electrodes to increase the radiance in those portions of the discharge vessel.