Abstract: A measuring arrangement for detecting trace gases in a sample gas, the measuring arrangement includes at least one narrow-band excitation light source; first and second chambers, wherein the excitation light is emitted into the chambers; a scrubber, wherein trace gases are removed from the sample gas as it passes between the first and second chambers; at least one narrow-band measurement light source arranged such that the measurement light hits the excitation light in the first chamber and second chambers; a detector unit which is in optical contact with the first and second chambers and detects the measurement light from the first and second chambers and converts it into a first and a second electrical signal; and a data processing unit which calculates the amount of trace gases in the sample gas from the first and second electrical signals. The present disclosure also discloses an alternative measuring arrangement and method.

Abstract: A gas sensor for determining a concentration of at least one gas in a gas mixture includes: at least one intensity modulatable light source; a measuring section, into which the gas mixture to be investigated can be allowed to flow; and an essentially gas-sealed detection cell, wherein the gas sensor is embodied such that light emitted from the light source is radiated into a measuring section, wherein the intensity of the emitted light is modulated with a modulation frequency, which differs from the resonant frequency of a mode of the acoustic resonance of the detection cell by less than 0.5 times, especially less than 0.25 times, the half-width of the mode. Further, a method for determining the concentration of the at least one gas in the gas mixture uses the gas sensor.

Abstract: A sensor for determining a measurand dependent on a concentration of a gaseous analyte in a liquid medium includes: a closed measurement chamber with a gas sensor sensitive to the gaseous analyte for generating a measurement signal which is dependent on the concentration of the gaseous analyte in the measurement chamber; a diffusion membrane impermeable to liquid and gas-permeable to the gaseous analyte, which diffusion membrane closes the measurement chamber and includes a medium-contacting second surface; an evaluation unit for determining the measurand on the basis of the measurement signal; and an ultrasound emission unit designed to introduce ultrasonic waves into the medium such that a mixing of the medium is generated in a volume adjacent the medium-contacting second surface. Further disclosed is a method for determining the measurand dependent on the concentration of the gaseous analyte in the liquid medium using the disclosed sensor.

Abstract: A stereoscopic measuring device for determining position information of an event location comprises a background surface and a lighting assembly having a first lighting position and a second lighting position for the illumination of the background surface at different angles. The light beams from the lighting positions passing through an event location are projected at spaced-apart projection locations at a projection location distance. The measuring device also includes an imaging apparatus for imaging the projection locations and an evaluation apparatus for detecting an event, for determining the projection location distance and the position information of the event location based on the projection location distance. The event location is a location at which the medium to be detected appears. Its interaction with the light beams changes a property of the projection locations compared to reference conditions in which the medium to be detected is absent or effective in a different way.

Abstract: A sensor for determining a measurand dependent on a concentration of a gaseous analyte in a liquid medium includes: a closed measurement chamber with a gas sensor sensitive to the gaseous analyte for generating a measurement signal which is dependent on the concentration of the gaseous analyte in the measurement chamber; a diffusion membrane impermeable to liquid and gas-permeable to the gaseous analyte, which diffusion membrane closes the measurement chamber and includes a medium-contacting second surface; an evaluation unit for determining the measurand on the basis of the measurement signal; and an ultrasound emission unit designed to introduce ultrasonic waves into the medium such that a mixing of the medium is generated in a volume adjacent the medium-contacting second surface. Further disclosed is a method for determining the measurand dependent on the concentration of the gaseous analyte in the liquid medium using the disclosed sensor.