Abstract: A description is given of an operating method for a discharge lamp with dielectrically impeded discharges and also a corresponding ballast and illumination system. The invention is directed at withdrawing the external lamp voltage across the discharge lamp in order to produce a back ignition in the lamp by virtue of an internal counterpolarization. The back ignition improves the efficiency of the lamp operation and makes it possible to construct a very small, lightweight ballast.

Abstract: A metal halide lamp has a ceramic discharge vessel with two ends (5) which are closed off by sealing means which enclose a capillary tube (11). An electrically conductive lead-through (9) is passed in a vacuum-tight manner through a bore in the capillary tube (11). The capillary tube (11) comprises two sections (20,21) which are arranged axially one behind the other, the diameter of the bore of the inner section amounting to at most 90% of the diameter of the bore in the outer section.

Abstract: A method and a circuit for operating a direct current metal halide arc lamp. The lamp is activated by a periodic signal UL(t), and the duration Taus between the beginning of the fall from a maximum value and the subsequent rise in signal amplitude ranges from 1 to 50 &mgr;s. A pulsator is arranged between the ballast and the starter in addition to a direct current metal halide arc lamp which is filled by additional constituents, namely thallium, at a concentration of 0.6 to 3.0 &mgr;mol/ml in addition to an ignition gas, mercury, and lithium at a concentration of 0.2 to 0.5 &mgr;mol/ml.

Abstract: The invention relates to a motor vehicle lamp having a light source (4), at least one optical conductor (6) which is optically coupled to the light source (4), and operating means (5) for the light source (4). The optical conductor (6) has a light exit surface (8) whose curvature is adapted according to the invention to the curvature of the motor vehicle.

Abstract: The invention relates to an electric lamp, provided with a metal-plastic cap, for a motor vehicle headlight. In order to prevent maladjustment of the lamp, caused by the formation of burrs on the reflector (20), during installation in the mounting opening (21), designed as a lampholder, of the reflector (20), the lamp cap (14b) is fitted with depressions (14f) or cutouts so that any possible burr (22a2) on the edge (22a) of the mounting opening (21) is arranged free from contact with the lamp cap (14b, 15).

Abstract: The present invention relates to a method for marking quartz glass lamps having at least one fusible metal foil 10, 12, which is surrounded by quartz glass, for supplying electric voltage to luminous means 15 arranged in the interior chamber of a lamp vessel, in which method the fusible metal foil 10, 12 is marked through the quartz glass by means of a laser. The invention also relates to a quartz glass lamp having at least one fusible metal foil 10, 12 which is surrounded by quartz glass, for supplying electric voltage to luminous means 15 arranged in the interior chamber of a lamp vessel, in which lamp the fusible metal foil 10, 12 forms a marking area 16, the marking of the marking area 16 taking place through the quartz glass by means of a laser.

Abstract: An electrical circuit arrangement for producing pulsed-voltage sequences for the operation of discharges which are impeded dielectrically comprises a series circuit formed from a tuned circuit inductance (TR2-A) and a controlled switch (T1), a pulse generator (OS) which drives the switch (T1), an electrical valve (D1) which is connected in parallel with the switch (T1), a tuned circuit capacitance (C2) which is likewise connected in parallel with the switch (T1), a means (TR2-B, a″, b″) for coupling a lamp (La1) to at least one electrode which is impeded dielectrically, and, optionally, a buffer and feedback capacitor (C1) which is connected in parallel with the series circuit formed by the tuned circuit inductance (TR2-A) and the switch (T1).

Abstract: A high-pressure discharge lamp has integrated in its base or base housing a circuit arrangement (SCH) which combines a starting device and a power reducing circuit which comprises a phase-gating control (PS). A capacitor (C2) connected in parallel with the lamp (L) provides a transfer voltage which is distinctly higher than the input voltage of the arrangement.

Abstract: A ballast for a gas discharge lamp having an inverter. A DC voltage source feeds the ballast. A bridge circuit is arranged in parallel with the DC voltage source. The bridge circuit has first and second controllable switches. The midpoint of the bridge is connected to a load circuit having the gas discharge lamp. The gas discharge lamp has first and second electrodes. A control circuit controls the pulse duty factor of the first and second switches. The pulse duty factor is not equal to 50%. The control circuit controls the pulse duty factor such that the first and second electrodes are subjected to essentially the same thermal load on average.

Abstract: The invention relates to a method for adjusting at least one operating parameter of an operating unit (EVG), equipped with a microcontroller (MC), for electric lamps. The adjusting method according to the invention includes a closed loop which carries out a successive correction of at least one drive parameter, stored in the microcontroller (MC), for the voltage transformer of the operating unit (EVG). There is no need for an adjusting resistor.

Abstract: A discharge lamp (1) including a tubular discharge vessel (2), filled with inert gas and, optionally, a fluorescent layer, having at least three elongated electrodes (3, 4, 5) arranged parallel to the longitudinal axis of the tubular discharge vessel (2). The electrodes are arranged in such a manner that the relationship s a ≥ 0.1 is satisfied, wherein s is the maximum spacing between an imaginary connecting line of an electrode pair and the most closely neighboring point on the wall of the tubular discharge vessel, and a is the mutual spacing between the electrodes of such electrode pair. A higher luminous density is achieved in this way. The lamp is particularly advantageous for a pulsed, dielectrically impeded discharge.

Abstract: Flickering phenomena in gas discharge lamps are undesired in projection technology, in particular. According to the invention, the problem is solved by setting a lamp operation which does not form a focal spot. A specific control structure which includes a cascade structure and feedforward control is proposed for implementing this operation.

Abstract: The invention relates to a device for controlling light sources (30-35) having a ballast (20-23), it being possible to connect the device to a set point generator for prescribing a brightness set point for the light sources (30-35), and having means for generating a control signal, dependent on the set point of the set point generator, for the purpose of brightness control of the light sources (30-35). According to the invention, the device has means for adapting the control signal to different types of light sources. The device according to the invention renders possible uniform dimming of different types of light sources which are installed in a lighting system.

Abstract: A supply lead (7) for a halogen incandescent lamp is bent in a U-shaped fashion and comprises a base (15) and two limbs (16). The ends of the limbs engage in the end region (6) of the luminous element by means of hook parts (20). A section (11) at the end, on the side of the luminous element, of the associated foil is folded back and forms a fold (12) in which the base (15) is held mechanically.

Abstract: The invention relates to an electric lamp, comprising a base (3) having at least two V-shaped fixing plates (5; 6) with a first (5a, 6a) and a second elastic V-shaped limb (5b; 6b). The ends of the first V-shaped limb (5a, 6a) are formed on the base (3). The first V-shaped limb (5a; 6a) forms a location (7) to accommodate a tappet-like holder or connector part and the ends of the second V-shaped limb (5b; 6b) arm configured as free ends. The inventive lamp can be used in a sealed headlight of a motor vehicle and on a carrier plate fitted with several lamp holders and forming part of the tail lights of a motor vehicle.

Abstract: The invention relates to a method for operating a discharge lamp, which has at least one dielectrically impeded electrode (2, 3), on a flyback converter, which applies periodically recurring voltage pulses to the discharge lamp (La1). If the discharge lamp (La1) has a starting aid (10), the voltage amplitude (US) of the voltage pulses is successively raised until a dielectrically impeded discharge is formed in the discharge lamp, and until the voltage amplitude (US) has reached the nominal operating voltage. If the discharge lamp (La1) has no starting aid, a first discharge which causes a partial ionization of the discharge medium is firstly ignited in the discharge lamp (La1). Immediately after the first discharge has been brought back to extinction, a dielectrically impeded discharge is ignited anew, and the voltage amplitude (US) of the voltage pulses is increased until the nominal operating voltage of the discharge lamp (La1) is reached.

Abstract: The invention relates to a circuit arrangement having a half-bridge arrangement comprising a first and a second switch (T1;T2), each switch (T1;T2) having, between its operating and reference electrodes, an internal diode (DB1;DB2), which is reverse-connected in parallel with the main current flow direction of the respective switch (T1;T2), and also an internal capacitance (COSS1;COSS2), a series diode (DS1;DS2) being arranged in series with the respective switch (T1;T2) in the main current flow direction in such a way that current can flow in the main current flow direction, and a freewheeling diode (DF1;DF2) being connected in parallel with the respective series circuit formed by the switch (T1;T2) and the series diode (DS1;DS2), and having a load circuit (L;RL), which has at least one inductive component (L) and is connected to the midpoint of the half-bridge arrangement.

Abstract: The invention relates to a half-bridge inverter including a first and a second input terminal (E, N), which form an input of the inverter, a first and a second output terminal (B, A), which form an output of the inverter, a series circuit having a first and a second coupling capacitor (C1, C2), which series circuit is connected in parallel with the input and forms the passive bridge path, the midpoint of the series circuit made up of the first and the second coupling capacitor (C1, C2) being connected to the first output terminal (B), a series circuit having a first and a second switch (S1, S2), which series circuit forms the active bridge path and has its midpoint connected to the second output terminal (A), where a storage capacitor (C3) is arranged in parallel with the active bridge path, and the first coupling capacitor (C1) is connected to the storage capacitor (C3) via a first inductor (L1), and the second coupling capacitor (C2) is connected to the storage capacitor (C3) via a second inductor (L2).

Abstract: The invention relates to a miniature incandescent lamp which is provided for mounting on a printed circuit board. According to the invention, the base contacts (7) have a plane contact surface (7a) for soldering onto a printed circuit board, a section (7b, 7c, 7d) which is constructed like tongs and serves to anchor the base contact (7) in the lamp base, and a hookshaped section (7e) into which one end of a supply lead (5) guided out of the lamp bulb (1) is inserted, and to which said supply lead (5) is welded.

Abstract: The invention relates to a circuit for power-factor correction having a rectifier (14) which can be connected on the input side to an AC voltage source (10) and which is connected on the output side to at least one series circuit comprising a capacitor (CS1) and a diode (DS1), with the diode (DS1) being arranged such that the capacitor (CS1; CS2) cannot be charged through the diode (DS1; DS2) by the output signal from the rectifier (14), a first and a second electronic switch (T1, T2) connected in series as part of a half bridge or full bridge, each having a freewheeling diode (DF1; DF2) connected in parallel with the switch (T1; T2) and, with the [lacuna] formed by the junction point between the first and second switches (T1, T2) [lacuna] an output connection of the half bridge or full bridge is on the one hand connected via an inductance (L) to a point on the connection of the capacitor (CS1) and diode (DS1) of each series circuit comprising a capacitor (CS1) and a diode (DS1), and on th