An optical temperature sensor based on Silicone and Plastic Optical Fibers for biomedical applications

A low cost and simple to realize optical temperature sensor is proposed. The sensor is fabricated on the fiber end by removing, near the fiber tip, the cladding of a multimode plastic optical fiber (POF) with a polishing process, to deposit, by dip coating, a silicone layer around the fiber tip. We have experimentally tested the sensor by measuring, at different wavelengths, the temperature of a water bath. The best sensor's performances were obtained at a wavelength of 625 nm. The novel polymer optical fiber sensor exhibits a good linear response in the temperature range from 24 degrees C to 46 degrees C. This temperature range is interesting for hyperthermia in cancer treatment.