Phase shift response of birefringent PANDA fiber after the end of thermal exposure during recovery to ambient temperature

The aim of this work is to point out the current possibilities of using polarized light in sensor technology. Furthermore, the aim is to demonstrate the possibility of using the fiber sensor of thermal field disturbance as a truly feasible biomedical sensor applicable in medicine and especially to analyse different ways of measuring polarization changes. This paper concludes theoretical and experimental study deal with temperature response of birefringent fiber. It is supposed to use it for design of sensor of temperature disturbance. The paper follows up on the previous works, where the response of the birefringent PANDA fiber to thermal exposure in the temperature range from 0 to 48 °C was studied. These experiments analyzed the dynamic sensitivity characteristic of birefringent fiber for the process of thermal source apposition. The present paper brings a detailed comparative analysis of fiber response to the processes of apposition and the removal of thermal source, which are evaluated from the point of view of the system’s response after the ending of the thermal exposure. For practical use in fiber recovery analyses, the phase development rotation senses are described on the observable Poincare sphere.