Abstract: An electroluminescent (EL) element is connected to the power supply and is intermittently operated as a lighting device and as a brightness sensor. For this purpose, the processing unit induces the controlled AC voltage source to reduce the voltage for a short period. The current intensity is measured by current measuring devices and the corresponding measuring signal is digitized using the analog/digital converter (A/D). A processing unit uses the signal and the effective voltage to determine, by means of empirical calibration data stored in the memory or by using a calibration function, the brightness, i.e. the luminance of the light that is incident on the EL element. The processing unit associates, using desired values stored in the memory, the detected brightness with an operating voltage level which ensures the desired emission brightness of the EL element when operated as a lighting device.

Abstract: The invention relates to a method for compensating the ageing-related loss of luminosity of an electroluminescence element, according to which the cumulative electrical energy supply, i.e. the integral of the supplied electrical power over the period of operation, is used as a criteria for the compensating regulation of the operating voltage. The processing unit continuously integrates the supplied electrical power over time. The relation between the operating voltage and the emission luminosity of the electroluminescence element is stored in the memory for different cumulative electrical energy supplies. The stored data can be defined by means of a model or estimated on the basis of empirical values. The relation can be stored in the form of values stored in a tabular manner or as an analytical function in the memory.

Abstract: The invention relates to an electroluminescence element (1) comprising a light-permeable first electrode (4), a luminescence layer (5), a second electrode (7), and a protective laminate (8). The invention is characterised in that the protective laminate (8) has a water-vapour permeability of between 0.35 g/m2/24 h at 38° C. and 100% relative atmospheric humidity and 10 g/m2/24 h at 38° C. and 100% relative atmospheric humidity.

Abstract: The invention relates to a method for compensating the ageing-related loss of luminosity of an electroluminescence element, according to which the cumulative electrical energy supply, i.e. the integral of the supplied electrical power over the period of operation, is used as a criteria for the compensating regulation of the operating voltage. The processing unit continuously integrates the supplied electrical power over time. The relation between the operating voltage and the emission luminosity of the electroluminescence element is stored in the memory for different cumulative electrical energy supplies. The stored data can be defined by means of a model or estimated on the basis of empirical values. The relation can be stored in the form of values stored in a tabular manner or as an analytical function in the memory.

Abstract: An electroluminescent (EL) element is connected to the power supply and is intermittently operated as a lighting device and as a brightness sensor. For this purpose, the processing unit induces the controlled AC voltage source to reduce the voltage for a short period. The current intensity is measured by current measuring devices and the corresponding measuring signal is digitized using the analog/digital converter (A/D). A processing unit uses the signal and the effective voltage to determine, by means of empirical calibration data stored in the memory or by using a calibration function, the brightness, i.e. the luminance of the light that is incident on the EL element. The processing unit associates, using desired values stored in the memory, the detected brightness with an operating voltage level which ensures the desired emission brightness of the EL element when operated as a lighting device.

Abstract: The electroluminescent (EL) element comprises a transparent plastic film substrate (1) onto whose rear side a transparent first electrode layer (2) comprised of indium tin oxide (ITO) is vacuum sputtered. A first electroluminescent layer (3) with dispersed electroluminophores (4) is placed on the first electrode layer (2). This first electroluminescent layer consists of a transparent matrix (5) into which the electroluminophores (4) are incorporated (4). The second electrode layer (rear electrode layer) (6) is placed on the first electroluminescent layer (3) or on an insulating intermediate layer (not shown) located thereon. This second electrode layer is insulated toward its side facing away from the first electroluminescent layer (3) by means of the insulating layer (7). On the front side, i.e. the visible face, a third electrode layer (8) comprised of transparent conductive lacquer is applied to the plastic film substrate (1).

Abstract: The invention relates to an electroluminescent film providing a particularly advantageous compromise between the safe functioning and simplified production thereof. The inventive polychromatic electroluminescent element consists of three similar electroluminescent films which contain dispersed electroluminophors and whose colors are not different from each other. The different colors are obtainable by an additional color mixture by means of a separate electric excitation of each electroluminescent film. Each of the films essentially comprises a support made of PET or other plastic material on which an electrode layer is vapour-deposited or cathode-sputtered, a luminous layer on which a rear transparent electrode is placed by serigraphy and laminated by means of an insulating foil.