Figure 5
From: Nano silica diaphragm in-fiber cavity for gas pressure measurement
Sensor specimens based on an optimized sensing diaphragm. (a1) Optical microscopy image of specimen FAB2 with a cavity length of about 155 µm and a diaphragm thickness of about 290 nm. (a2) The reflection spectrum of FAB2. (a3) Wavelength shift of the interference fringe around 1530 nm with the gas pressure varying from 0 to 1.0 MPa, and the slope of the linear fitting is about 1.33 × 10−3 nm/kPa, reflecting a corresponding gas pressure sensitivity of about 1.27 × 10−1 nm/kPa. The inset presents the reflection spectral evolution. (b1) Optical microscopy image of specimen FDC2 employing an FDC with a cavity length of about 55 µm and a diaphragm thickness of about 250 nm. (b2) The reflection spectrum of FDC2. (b3) Wavelength shift of the interference fringe around 1530 nm with the pressure varying from 0 to 50 kPa, and the corresponding gas pressure sensitivity based on the slope of the linear fitting is about 12.22 nm/kPa. The inset presents the reflection spectral evolution.
