Abstract: A metal halide lamp for general illumination purposes contains as the essential component of the metal halide fill manganese in an amount of from 0.01 to 50 &mgr;mol per cm3. It serves as a replacement for sodium at warm white or neutral white luminous colors.

Abstract: The drive circuit is suitable for an LED array, comprising a number of clusters of LEDs, with one cluster comprising a number of LEDs which are arranged in series and are connected to a supply voltage (UBatt). A semiconductor switch (transistor T) is arranged in series between the LED and the supply voltage and allows the LED current to be supplied in a pulsed manner. A measurement resistor (Rshunt) for measuring the LED current is arranged in series between the LED and ground, with a control loop controlling the semiconductor switch such that a constant mean value of the LED current is achieved.

Abstract: The present invention relates to oxidic nanocrystals and a process and apparatus for producing oxidic nanocrystals from metalorganic compounds or volatile inorganic compounds. In particular, the process is suitable for oxidic or oxysulfidic nanocrystals, particularly based on the elements Y, Gd, Mg, Ca, Ba and Al. The nanocrystals preferably have a mean initial particle size of 1 to 20 nm.

Abstract: A flat lighting device (1) has an optical conductor plate (2) and at least two electric light sources (3, 4) which are suitable for coupling light into an optical conductor plate (2) during operation. A first light source (3) is arranged adjacent to the optical conductor plate (2), and a second light source (4) is arranged downstream of the first light source (3) with reference to the optical conductor plate (2) in such a way that at least a portion of the light emitted by the second light source (4) during operation can pass through the first light source (3) into the optical conductor plate (2). In dimmed operation, the first light source (3), which is closest to the optical conductor plate (2), is switched off and reduces the light flux to be coupled into the optical conductor plate (2) from the second light source (4). Extreme dimming is also possible in this way without there being a change in the electric and/or lighting properties of the light source.

Abstract: The invention relates to an electronic unit having a mounting board (4) and electronic components (1-3) mounted on it, with the mounting board (4) having metal webs (41) which are embedded in an electrically insulating material (40), the metal webs (41) having a first side (411), which is in the form of a contact surface for making contact with the electronic components (1-3) and having a second side (412) facing away from this. According to the invention, cutout(s) are arranged in the electrically insulating material (40), via which the second side (412) of each metal web (41) is accessible for a voltage or current measurement apparatus.

Abstract: Flat radiator with dielectrically impeded discharge with an areally inhomogeneous electrode geometry for local modulation of the surface luminance, primarily for application in the field of indicating devices, for instance in motorized means of transport.

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: In a lighting system which includes an electronic operating device and a gas discharge lamp with filaments, one filament terminal is respectively connected to an impedance network. The impedance network has an impedance function with a zero point at the frequency f1. For preheating purposes, the electronic operating device outputs a voltage whose frequency is close to the frequency f1. As a result, the voltage across the lamp is below the non-starting voltage during preheating.

Abstract: Disconnection device for an electronic operating device for gas discharge lamps. The filament breakage of a lamp is evaluated by detecting the current through a component which flows through the filaments. This is performed either by detecting this current with the aid of an optocoupler or by measuring the phase of the load circuit current.

Abstract: The invention relates to an operating method and an operating device for at least one electric lamp (11),which device has a control input (13, 14) for prescribing a setpoint for the brightness control of the lamp (11), and a transformer (15) for transmitting the voltage impressed on the control input (13, 14) to an evaluation device (16) which serves to evaluate the voltage impressed on the control input (13, 14).

Abstract: Metal halide lamp for color applications for high wall loading with a long service life of at least 1500 hours and with a color temperature of over 5000 K: fill comprising at least the following constituents: firing gas, mercury, halogen, as well as indium, thallium, tin, no rare earth element or Na; the fill furthermore contains, as lithium replacement, hafnium, zirconium and tantalum, individually or in combination, the wall loading of the discharge vessel being at least 50 W/cm2; specific output based on die arc length is 50 to 90 W/mm; in particular, the concentration of the metals is as follows: lithium replacements: 0.20-4.0 &mgr;mol/ml; indium 0.3-3.0 &mgr;mol/ml.

Abstract: The invention relates to an apparatus for operating at least one light-emitting diode (LD) comprising an electronic transformer (10), the output of the electronic transformer (10) having a high-frequency rectifier (12) connected to it whose output is connected to at least one light-emitting diode (LD), the high-frequency rectifier (12) and the at least one light-emitting diode (LD) being combined to form a separate physical unit (14).

Abstract: The invention relates to a signaling lamp with VUV phosphor excitation, in particular for traffic applications. It further relates to the use of phosphor mixtures for red, green and yellow signaling lamps and to a correspondingly constructed traffic light. (FIG. 1).

Abstract: The present invention relates to a method for providing an output signal (Ua) having a desired value of a characteristic quantity (Uarms) at the output of a switched-mode power supply unit. At least one low-voltage lamp is connected to the output of the switched-mode power supply unit. A load current (IL) corresponds to the sum of the currents (I1, I2) flowing through all the low-voltage lamps. The input side the switched-mode power supply unit is driven by an input signal (Ue1, Ue2) having at least one variable characteristic quantity (PW), and the switched-mode power supply unit is connected to an operating voltage (UB).

Abstract: Disconnection device for an electronic operating device for gas discharge lamps. The DC component is evaluated at a coupling capacitor (C5) specifically via a filament. Disconnection is performed in the event of filament breakage. In addition, the AC component of the generator output (O) can be monitored via a second filament, and disconnection can therefore also be performed in the event of breakage of the second filament.

Abstract: A description is given of a method for dimming discharge lamps with dielectrically impeded discharges. A continuous or discontinuous power control can be effected by influencing an electric parameter of a pulsed active-power supply and by means of a suitable electrode structure.

Abstract: An optoelectronic component group has at least two LEDs (2) which are mounted on a support (3). The support is composed of a material having a thermal conductivity of better than 1.5 W/K×m, for example ceramic or composite material.

Abstract: The invention proposes arranging a getter (7) made from niobium on the electrode rod (4) of a mercury short-arc lamp, the two following conditions being fulfilled: D>1.8·d and &agr;≧20°. In this case, D and d denote a diameter of the relevant electrode head (2) or the associated electrode rod (4), and &agr; denotes an angle which is defined by the longitudinal axis of the electrode and an imaginary connecting line between the end of the getter (7) averted from the electrode head, and a point on the perpendicular, running through the end of the electrode rod on the electrode head side, to the electrode longitudinal axis. The point mentioned corresponds to the projection of the maximum radius of the lateral surface of the electrode head onto this perpendicular. An improved maintenance of the lamp is thereby achieved.

Abstract: A circuit arrangement for igniting a lamp, in particular a high-pressure discharge lamp. The lamp has an ignition transformer with a primary side and a secondary side, the secondary side is connected to the lamp which is to be ignited, and the primary side is connected to an ignition switch. The ignition switch is controlled for actively disconnecting a current flowing through the primary side of the ignition transformer.

Abstract: A fluorescent lamp 1 for exterior lighting having a discharge tube 2 of less than or equal to 26 mm outside diameter. Starting from a fluorescent lamp for interior use having a discharge tube 2 of less than or equal to 26 mm, it is possible to achieve optimum operation of the fluorescent lamp 1 in the case of exterior use by applying a thermally conducting material in the form of a coating of foil 15, 16 outside on the discharge tube 2 in the region of one or both electrodes 3, 4.