Abstract: A ballast having a dimming device for a low-pressure discharge lamp. For brightness control, the DC component of the periodically modulated envelope of the lamp current is varied. In this case, the current does not fall below predetermined minimum values for the lamp current. Phases with a high lamp current are characterized by a steep rising edge, compared with a flatter falling edge.

Abstract: A reflector device for a lighting device, having a reflector element that has a light emission side and a back side facing away from the light emission side. From the back side to the light emission side, at least one mounting opening is provided, through which an electrically conductive connection element is intended to be passed by its second end region and coupled with the reflector element. The connection element, in turn, serves the purpose of coupling to an individual lamp on the one hand and an electrical power source on the other, and in its first end region it has means for securing the reflector device in a retention device. It furthermore has a third region, adjoining the first end region, that has a round diameter in cross section, and this diameter does not increase between the third region and the second end region.

Abstract: A color-tunable illumination system for imaging illumination having a tuning means and at least two light sources of different colors. The illumination system comprises a reflector having a reflector contour, the light sources being accommodated in the vicinity of the reflector contour, and a compact diffusing medium accommodated at the focal point of the reflector. The light from the light sources is directed substantially onto the diffusing medium and then, from there, is diffused onto the reflector contour, electronic driving of the light sources making it possible to regulate the intensity of the light sources separately from one another, with the result that the light leaving the reflector can be color-tuned.

Abstract: An illumination system for imaging illumination having at least one compact light source. The illumination system comprises a reflector having a reflector contour, the light source being accommodated in the vicinity of the reflector contour. A compact diffusing medium is accommodated at the focal point of the reflector, the light from the light sources being directed substantially onto the diffusing medium and, from there, being diffused onto the reflector contour, with the result that the light leaving the reflector is emitted homogeneously.

Abstract: The phosphor having the composition xAE2SiO4:D.yREN, in which AE=(Sr, Ba, Ca, Mg) and D=Eu, and RE=La, Y, delivers a blue to yellow-orange emission and is distinguished by a high efficiency. It can be used for a very wide range of light sources.

Abstract: A ballast having a dimming device for a low-pressure discharge lamp. It has two technically different possibilities for controlling the lamp brightness. The first possibility for controlling the lamp brightness is by means of adjusting the amplitude of the lamp current. The second possibility for brightness control is based on the fact that the low-pressure discharge lamp can be operated with a pulsed lamp current. In particular, both operating modes are used in combination in specific brightness ranges.

Abstract: A ballast having a dimming device for a low-pressure discharge lamp. For brightness control, the DC component of the periodically modulated envelope of the lamp current is varied. In this case, the current does not fall below predetermined minimum values for the lamp current. Phases with a high lamp current are characterized by a steep rising edge, compared with a flatter falling edge.