Printed Optical Sensors Towards Breathing Detection

This work demonstrates the possibility of fabricating optical sensors by printing the corresponding sensitive optical waveguides directly onto a flat substrate. Specifically, humidity-sensitive polymeric waveguides have been printed towards breathing sensing. The optical sensitive waveguides manufactured are compact, ensuring coupling with the input and output optical fibers. The response of the printed optical sensor was evaluated to humidity variations. Unlike the traditional manufacturing process, any modification in the material, structure, dimensions, etc. of the sensitive optical waveguide can be carried out in a simple, low cost and extremely fast way.