INTEGRATED OPTICAL MICROMACHINED PRESSURE SENSOR WITH SPECTRALLY ENCODED OUTPUT AND TEMPERATURE COMPENSATION

A promising type of optical pressure sensor combines an integrated opt ical interferometer with a micro-machined diaphragm on a shared silico n substrate. We have demonstrated a sensor of this type that uses an u nbalanced Mach-Zehnder waveguide interferometer together with a broadb and source to produce a spectrally encoded measurement. This spectral encoding mechanism is advantageous as it is not readily degraded by tr ansmission through optical fibers. We have also demonstrated a means t o obtain a temperature-compensated pressure measurement by interrogati ng both polarization eigenmodes of the interferometer. (C) 1998 Optica l Society of America.