Abstract: Disclosed is a method for quality control of a material layer, which involves providing the material of the layer with an agent for absorbing an electromagnetic radiation, irradiating the surface of the layer with an electromagnetic radiation, and measuring the amount of light emitted by the material layer, for example, reflected radiation or fluorescence radiation.

Abstract: The invention concerns a device and a method for carrying out fluorescence immunoassays, wherein from at least one light source light is directed onto a surface at one end of a light waveguide and with the light coupled into the light waveguide by evanescent field excitation at the surface of the light waveguide fluorescence of at least one labelling substance bound to a chemical or biochemical partner of a general receptor-ligand system is excited. The solution according to the invention is here to provide a possible way of carrying out fluorescence immunoassays with high accuracy of measurement at low cost and within a short time. To achieve this object, the fluorescent light is decoupled from the light waveguide and directed via an optical system onto an optical detector with which the intensity of the fluorescent light is measured.

Abstract: In a process for recognizing organic substances in solids by measuring the spectram of the radiation which is reflected or transmitted, radiation with a wavelength between 2-4 &mgr;m is used and, for radiation of solids, unmodulated radiation is used. The radiation source should have an output of at least 50 W and the distance between the illumination optics from the solid being investigated should be at least 10 cm. Recognition is based on absorption bands of the extended oscillations of C—H bonds and sometimes the presence of absorption bands of N—H bonds. Broad band radiation is preferable for radiation of the solids, and the reflected or transmitted radiation is directed through a narrow band filter with adjustable transmission frequency. This can be advantageously formed with an acousto-optical filter.

Abstract: The invention concerns a cation-selective sensor provided with a cation-selective coating and based on the fact that analyte ions present in a solution cause detectable changes in the electrical characteristics of the layer. The acid/base components in the cation-selective layer render the sensor function independent of the anions present in the analyte solution. This improves the measurement accuracy and lowers the detection threshold.

Abstract: There are proposed a method and a device for ascertaining the surface condition, particularly of traffic routes, as regards dryness, wetness or icing, in which the surface is irradiated by a radiation source with an infrared component, and the reflected radiation is measured simultaneously in different wavelength ranges characterizing water and ice. In this case at least four wavelength ranges are selected, permitting sufficient depth or penetration of the radiation into the surface. A first and a second wavelength range are so selected that they are influenced to a very small degree by absorption of the water molecules, and a third and fourth wavelength ranges are so selected that they are characteristic for water and ice. The influence of the background on signals measured in the third and fourth wavelength ranges is compensated for by means of the information in the signals measured in the first and second wavelength ranges.