The performance of the FP-based sensor was evaluated experimentally
using the same setup as that used to characterize the
FBG level sensor. Note that the sensor diaphragm had a thickness
of 0.5 m. In performing the tests, the pressure was increased
incrementally from 0.98 to 6.86 kPa in steps of 0.49 kPa.
At each pressure step, the cavity length was derived from an inspection
of the interference patterns in the spectral domain.