SENSORSYSTEM

A sensor system for measuring the light absorption in a target, e.g. a gas, comprising a first and a second optical transducer, one of which being a light source and the other being a light receiver, adapted to emit and detect, respectively, light within a chosen range of wavelengths, a partially reflective beam splitter adapted to reflect light to or from said first transducer, and to transmit light to or from said second transducer, and a lens or a group of lenses with a chosen focal length transmitting light to or from said transducers. The beam splitter comprises a first reflecting part and a second transmitting part being different from said first part, and a shield being positioned between said transmitting part and said first transducer.