In this paper a new concept of human breath detection by means of fiber Bragg grating (FBG) based temperature sensor
is reported. In presented approach, temperature of exhaled air is directly measured by FBG, and its Bragg wavelength
changes allow for determine breathing rate. Experimental results of comparison the FBG sensor with electronic one,
show significant advantages of our solution, especially when faster and/or plate breathing is detected. Another advantage
of proposed fiber Bragg grating based breathing rate sensor is its ability to work in the high electromagnetic field
environment, for example during the magnetic resonance imaging.
In this paper, methods for Bragg wavelength corrections in Talbot interferometer for FBG inscription are presented. As a result, a significant improvement of FBG inscription is achieved. Experimental results show that minimization of positioning errors of rotation stages, imperfections of Talbot interferometer construction as well as consideration of fiber dispersion, lead to a Bragg wavelength accuracy not worse than in commercially available gratings but within much wider spectral range. Proposed approach can compete in terms of Bragg wavelength accuracy with the recognized as more precise phase mask method.