Patent ID: 8580199

Claim:
A sensor for measuring oxygen content in a liquid or gaseous sample, comprising a light guiding means having a first end face for receiving luminescence excitation light from a light source and a second end face opposite the first end face, an active region applied to the second end face, the light guiding means being disposed to guide the luminescence excitation light to the active region, and the light guiding means further guides luminescence emission light from the active region to a detector, characterized in that the active region comprises a first sensor section that has an oxygen-sensitive luminescent indicator dye embedded in an oxygen-permeable first polymer matrix and a second sensor section that has said oxygen-sensitive luminescent indicator dye embedded in an oxygen-impermeable second polymer matrix, the second sensor section being disposed between the first sensor section and the second end face of the light guiding means so that the first sensor section can be brought into contact with said sample and so that the light guiding means guides the luminescence excitation light from the light source to the first sensor section via the second sensor section and guides the luminescence emission light from both the first sensor section and the second sensor section via the second end face to the detector, so that the first and second sensor are positioned to be exposed to virtually identical optical conditions with the oxygen-permeable first polymer matrix being exposed to the sample and the oxygen-impermeable second polymer matrix being substantially protected from the sample by the first sensor section and so that the detector receives a luminescence signal composed of an oxygen-dependent component and an oxygen-independent component for measuring oxygen content of the sample independent of temperature.