A miniature fiber Bragg grating pressure sensor for in-vivo sensing applications

A miniature FBG pressure sensor is reported. Two optical fibers containing FBG arrays are twisted together and the sensing elements are enclosed in a specially designed structure to detect variations in the ambient pressure. It provides an overall diameter of ~1 mm which is extremely beneficial for the studies of peristalsis in the gastrointestinal tract and flow in the vascular system. The static and dynamic responses of the miniature catheter were calibrated and the results are presented.