Abstract: A light source (1) includes at least one light emitting device (2) capable of emitting electromagnetic radiation in the range from near ultraviolet to blue in response to a driving signal of a driving means (6). A luminescent cover (3) includes at least a first activator (A1) and a second activator (A2) to convert the electromagnetic radiation into visible light. The first activator and second activator have different response characteristics and the driver is adapted to vary the driving signal to control the spectrum of said visible light for the light source.

Abstract: A high-pressure mercury vapor lamp suitable for sterilization purposes. Germanium and oxygen are added in small quantities to the mercury and/or the mercury halides, with a molar ratio of germanium to oxygen being greater than 1. The addition of germanium monoxide increases the GAC efficiency (GAC: short for Germicidal Action Curve) of a high-pressure mercury vapor lamp, because germanium monoxide emits a strong molecular band system in the range from 250 to 280 nm.

Abstract: The invention relates to a high-pressure mercury vapor lamp suitable for sterilization purposes. The high-pressure mercury vapor lamp according to the invention is remarkable in that germanium and oxygen are added in small quantities to the mercury and/or the mercury halides. The addition of germanium monoxide furthermore surprisingly increases the GAC efficiency (GAC: short for Germicidal Action Curve) of a high-pressure mercury vapor lamp, because germanium monoxide emits a strong molecular band system in the range from 250 to 280 nm. The germicidal action of the high-pressure mercury vapor lamp according to the invention is thus increased with respect to that of conventional highpressure mercury vapor lamps. This is apparent from the fact that the GAC-weighted radiant flux is greater than before in the high-pressure mercury vapor lamp according to the invention.

Abstract: The invention relates to a high-pressure gas-discharge lamp, having at least one gastight fused press-seal between a glasslike material and molybdenum, wherein the molybdenum in the fused press-seal is at least partly exposed to an oxidizing environment and at least that part of the molybdenum that is exposed to the oxidizing environment is covered with a coating, and the coating comprises at least one oxide from among Fe2O3, Ta2O5, Nb2O5, Al2O3, SiO2, TiO2, ZrO2, HfO2, and/or one nitride from among TiN, ZrN, HfN, AlN, BN, and/or one carbide from among TiC, ZrC, HfC, VC, NbC, TaC, B4C.

Abstract: A lamp system has a first light source which radiates light of a first chromaticity coordinate and a second light source which radiates light of a second chromaticity coordinate. The lamp system also includes an optical component for additively mixing the light of the two light sources. The optical component includes an optical waveguide with two different kinds of scattering centers for mixing the light as desired.

Abstract: A low-pressure gas discharge lamp provided with a gas discharge vessel comprising a gas filling with a discharge-maintaining composition comprising a discharge maintaining compound selected from the group formed by the compounds of aluminum, gallium, indium and thallium, an additive selected from the group of elemental zinc, cadmium and mercury and a buffer gas, which low-pressure gas discharge lamp is further provided with means for generating and maintaining a low-pressure gas discharge.

Abstract: A high-pressure metal halide discharge lamp which comprises, as filling, only zinc, a halogen and a noble gas. In order to improve the color rendering index, a calcium halide may be added to the lamp filling. The coupling-in of energy preferably takes place without electrodes in the radio-frequency range or in the microwave range, but may also be carried out by means of metal electrodes.

Abstract: A low-pressure gas discharge lamp includes a gas discharge vessel containing an inert gas filling as a buffer gas, and electrodes for generating and maintaining a low-pressure gas discharge. The lamp contains at least one tin halide.

Abstract: The invention relates to a high-pressure discharge lamp with a discharge vessel having a filling comprising—a rare gas, for example argon, —mercury, and —chlorine, wherein the filling quantities of mercury [Hg] and chlorine [Cl] comply with the following conditions: —[Hg](E[Cl]3 200 (?mole/cm3)2, —[Cl] £ 10 ?mole/cm3. The condition [Hg](E[Cl]3 200 (?mole/cm3)2 achieves HgCl vapor pressures in the discharge sufficient for generating significant radiation components of the B2S+-X2S+ band system of this molecule. The condition [Cl] £ 10 ?mole/cm3 serves to limit the chemical aggressiveness of the chlorine filling, in particular to limit the attacks on the wall and electrodes and thus to achieve longer lamp lives. The addition of chlorine-binding metals, in particular of germanium, leads to a further improvement in the radiation and life properties of the lamp.

Abstract: A low-pressure gas discharge lamp provided with a gas discharge vessel containing a mercury-free gas filling with an indium compound in an amount of about 1 to 10 microgram per cubic centimeter and a partial pressure in the range from 1.0 to 30 micro bar, and a buffer gas for emitting radiation in a continuous spectrum in the visible and near UVA regions of the electromagnetic spectrum, which low-pressure gas discharge lamp is also provided with electrodes and a ballast for controlling the ignition and operation of the lamp.

Abstract: A low-pressure gas discharge lamp comprising a gas discharge vessel with a gas filling containing an indium compound and a buffer gas, and comprising a phosphor layer containing at least one phosphor emitting in the visible range of the spectrum, and comprising electrodes and means for generating and maintaining a low-pressure gas discharge.

Abstract: A gas discharge lamp is described with a discharge gas comprising a light-emitting substance enclosed in a discharge vessel, which is characterized in particular in that the light-emitting substance is formed by a compound of at least one element from the group IV-A (Si, Ge, Sn, Pb) and at least one element from the group VI-A (O, S, Se, and Te) of the periodic system, with the exception of the compound GeSe. It was surprisingly found that the emission maximum lies approximately in the center of the visible spectral range of the light with such a substance, in particular GeTe, at a comparatively low vapor pressure already, and that in addition a very high radiant efficacy is obtained. Furthermore, the emitted light has a color temperature substantially corresponding to that of natural daylight also without additives, in contrast to many other gas discharge lamps, thus opening the way to a use of the lamp for general lighting purposes.

Abstract: A gas discharge lamp is described with at least one capacitive coupling structure (10, 10′), which lamp has the particular feature that the coupling structure (10, 10′) is provided for generating an electromagnetic field with a frequency below approximately 50 MHz, that it is formed by a metal element (101, 101′) surrounded by a dielectric layer (102, 102′) at least in the region of a discharge space, which layer is less than approximately 100 &mgr;m thick. It was surprisingly found that operation at low frequencies is possible with such a coupling structure, for which efficient ballasts are available. A further advantage is that this coupling structure compared with known coupling structures for frequencies below approximately 50 MHz only cause a minimum shadow effect. The efficacy of the entire system is considerably higher than that of known lamps of this kind for these two reasons.

Abstract: A low-pressure gas discharge lamp having a gas discharge vessel containing a gas filling with a chalcogenide of the elements of the 4th main group of the periodic systems of elements and a buffer gas, and having inner or outer electrodes and means for generating and maintaining a low-pressure gas discharge.

Abstract: A low-pressure gas discharge lamp having a gas discharge vessel containing a gas filling including a copper compound. The copper compound is selected from the oxides, chalcogenides, hydroxides, hydrides and the metalorganic compounds of copper. In addition to the copper compound, the gas filling includes a buffer gas such as argon, and may also include a thallium compound and/or a copper halogenide.

Abstract: A low-pressure gas discharge lamp comprising a gas discharge vessel containing a gas filling with a chalcogenide of the elements of the 4th main group of the periodic systems of elements and a buffer gas, and comprising inner or outer electrodes and means for generating and maintaining a low-pressure gas discharge.

Abstract: A low-pressure gas discharge lamp provided with a gas discharge vessel containing a gas filling with an indium compound and a buffer gas, which low-pressure gas discharge lamp is also provided with electrodes and means for generating and maintaining a low-pressure gas discharge.

Abstract: A low-pressure gas discharge lamp provided with a gas discharge vessel comprising a gas filling with a copper compound selected from the group formed by the oxides, chalcogenides, hydroxides, hydrides and the metalorganic compounds of copper, and comprising a buffer gas, which low-pressure gas discharge lamp is further provided with electrodes and means for generating and maintaining a low-pressure gas discharge.