Patent ID: 6879085

Claim:
A method of producing a piezoelectric vibrator comprising: producing a thin rectangular piezoelectric plate from a material having a Young's modulus, the plate having two short edge surfaces, two long edge surfaces, two large planar face surfaces and transverse and longitudinal resonant vibration modes respectively parallel to the short and long edges and having formed therein at least one cavity; forming at least one electrode on each of the planar surfaces that is electrifiable to excite at least one vibration mode of the plate; and determining a desired convergence or a desired divergence between resonant frequencies of a first vibration mode and a second vibration mode of the vibration modes of the plate relative to a difference in their frequencies in the absence of the at least one cavity; wherein the at least one cavity is not filled with a material having a Young's modulus substantially equal to the Young's modulus of the material from which the plate is formed and shifts the resonant frequencies of the first and second vibration modes to provide the desired convergence or divergence.