INDRETNING MED EN MÅLEINDRETNING TIL OPTISK MÅLING AF GASSER OG GASBLANDINGER MED KOMPENSATION FOR MILJØMÆSSIGE PÅVIRKNINGER

A device for optical detection of a target gas in gas mixtures includes an operation and evaluation unit, a measurement cuvette with optically reflective surfaces on its interior walls and a gas inlet to the environment, a radiation source, a measuring detector and a reference detector unit provided on the measurement cuvette. The measuring detector and the reference detector unit detect the light of the radiation source and produce electrical signals corresponding to the intensity of the detected light. An optical bandpass filter element, constructed to transmit light of a measurement wavelength, is arranged upstream of the measuring detector. An optical double-bandpass filter unit, that transmits light of a first reference wavelength and light of a second reference wavelength, is arranged upstream of the reference detector unit. The operation and evaluation unit operates the radiation source and acquires the electrical signals of the measurement detector and the reference detector unit.