Sensitivity dependences on side length and aspect ratio of a diaphragm in a glass-based guided-wave optical pressure sensor.

According to our previous theoretical study, sensor sensitivity is proportional to the cube of the side length of the diaphragm in a guided-wave optical pressure sensor consisting of a glass diaphragm and a single-mode waveguide on the diaphragm. Also, to obtain higher sensitivity, an aspect ratio of the diaphragm should be approximately 1 for two waveguide positions: the center and the edge of the diaphragm. In this study, sensitivity dependences on side length and aspect ratio of the diaphragm were experimentally examined. The obtained experimental results strongly supported the theoretical predictions.