Design and Fabrication of Micro Silica Sphere Cavity Force Sensor Based on Hybrid Fabry Perot Interferometer

摘要

Measurement of small force in biological applications could be helpful especially in the field of diagnostic and prognostic procedure. For this purpose, a Hybrid Fabry Perot fiber optic Micro Cavity is proposed based on Micro Silica Sphere Cavity integrated on the capillary tube, and is bound to the single mode fiber with PDMS layer. Since PDMS acts as an elastic material, under small loads the cavity length was affected. To study this mechanical behavior, the sensor structure was simulated with Finite element method. The force measurement was studied experimentally with analyzing wavelength shifts of sensor. Consequently, the force sensitivity was equal to -3pm/mN. The force resolution of our sensor was equal to 340 μN in the range of 0 to 950 mN.