A fiber-optic temperature sensor

In this paper we demonstrate the feasibility of designing a fiber-optic temperature sensor based on the principles of low-coherent tandem interferometry; the sensitive element represents a plane-parallel plate produced from fused silica of thickness 500 µm (the corresponding measurement range is between 40 and 90°C). In the middle of the range, the temperature resolution reaches 0.03°C RMS and goes down to 0.1°C RMS at the boundaries. The worst-case repeatability of measurements of the sensor makes up 0.2°C.