The experimental and theoretical results for the variation of
the cavity length with the pressure are shown in Fig. 5. It can
be seen that the FP pressure sensor has an approximately linear
response over the considered pressure range. From inspection,
the theoretical and experimental sensitivities of the sensor are
found to be 0.1998 m/kPa and 0.1569 m/kPa, respectively.
The difference can be explained that a nonparallel alignment of the optical fiber and glass tube and a nonuniform thickness of
the diaphragm.