1, and was then covered with a tightly fitting pressure
sensitive outer sleeve that induces a sideways deflection of the
fiber towards the axis of the substrate (indicated by an arrow
in the Figure) as the external pressure varies. The transducer
design allows a second fiber to be positioned along the bottom
edge of the substrate that can include an additional FBG
element or to run a second array of FBG transducers from the
end of the first array