Patent ID: 7626318

Claim:
A piezoelectric tuning fork resonator, including: a base; and first and second parallel vibrating arms having a generally tapered shape; wherein each of the vibrating arms is extended from the base by an enlarged portion in the shape of a flipper forming a free end of each arm, wherein each of the vibrating arms further includes at least one groove formed on at least one of the top or bottom surfaces of each of the vibrating arms, wherein each groove extends in a direction of a free end of an arm to beyond a start of the flipper, wherein each of the vibrating arms carries a set of excitation electrodes for vibrating the arms at a fundamental frequency, wherein the set of excitation electrodes includes central electrodes on the top and bottom surfaces of the arms and lateral electrodes along the sides of the arms, and wherein the central electrodes do not extend all the way to the start of the flippers, but stop before.