This oxygen sensor consists of a polymer optical fiber (POF) with a polished distal tip which is coated with a planar trace oxygen-sensitive foil.
The end of the polymer optical fiber is covered with a high-grade steel tube, to protect both the sensor material and the POF.
The cable has an outer diameter of 2.8 mm. The inner diameter of the POF is 2.0 mm. The steel tube has an outer diameter of 4 mm.
Usually, the fiber is coated with an optical isolated sensor material in order to exclude ambient light from the fiber tip and to increase chemical resistance especially against oily samples as well as to reduce bio-fouling on the sensor membrane. This type of oxygen sensor has an excellent long-term stability.