Fibre optic oxygen sensor based an unsymmetrical fibre coupler

The development of a fibre optic oxygen sensor system based on an unsymmetrical fibre coupler for the measurement of oxygen partial pressure (PO2) is reported. The principle of the oxygen sensor is based on the luminescence quenching of a luminophore by oxygen and the sensor consists of an unsymmetrical silica fibre coupler and a PMMA sensing medium that contains immobilized Pt (II) complexes. The 2x2 unsymmetrical optical fibres coupler was made using two silica fibres with different core diameters, one is with 200μm core diameter and another one is with 105μm core diameter. In our current work, the fibre coupler fibre was optimized to improve the performance of the sensor system by increasing light coupling efficiency from LED to sensor probe. The performance of the fibre optic oxygen sensors was evaluated using Ocean Optics spectrometer (USB2000) based on the luminescence intensity measurement. The details of the sensor chemistry, experimental system and the results were presented. As result, a special fibre coupler has been used to construct a practical, low cost oxygen sensor.