| Abstract: | A bulk micromachined vibratory gyro in which a proof mass has a bulk
substrate thickness for a large mass and high inertial sensitivity. In
embodiments, optical displacement transduction is with multi-layer
sub-wavelength gratings for high sensitivity and low cross-talk with
non-optical drive elements. In embodiments, the vibratory gyro includes a
plurality of multi-layer sub-wavelength gratings and a plurality of drive
electrodes to measure motion of the proof mass induced by drive forces
and/or moments and induced by the Coriolis Effect when the gyro
experiences a rotation. In embodiments, phase is varied across the
plurality gratings and a multi-layer grating having the best performance
is selected from the plurality. |