초록 ▼

A piezoelectric resonance device of the energy-trapped type utilizing a harmonic wave of the thickness extensional vibration mode, wherein three or more electrodes are so disposed that they are overlapped with each other through the piezoelectric layer in the direction of the thickness and each of t

A piezoelectric resonance device of the energy-trapped type utilizing a harmonic wave of the thickness extensional vibration mode, wherein three or more electrodes are so disposed that they are overlapped with each other through the piezoelectric layer in the direction of the thickness and each of the electrodes is comprised of a vibrating electrode portion for energy-trapping and a conducting portion for connecting the vibrating electrode to the side edge of the piezoelectric layer.

대표청구항 ▼

A piezoelectric resonance device of the energy-trapping-by-frequency-lowering type using a harmonic wave above the fundamental wave of the thickness extensional vibration mode, said device comprising: a plate-like body comprising a plurality of layers of a lead titanate-zirconate system piezoelectri

A piezoelectric resonance device of the energy-trapping-by-frequency-lowering type using a harmonic wave above the fundamental wave of the thickness extensional vibration mode, said device comprising: a plate-like body comprising a plurality of layers of a lead titanate-zirconate system piezoelectric material, said plurality of layers being stacked to form said plate-like body and thereby defining a direction of thickness; at least three electrodes so disposed that the electrodes are overlapped with each other on opposite sides of respective piezoelectric layers in said direction of thickness; each of said electrodes having a vibrating electrode portion and a conducting portion for connecting the vibrating electrode portion to a side edge of said plate-like body; wherein all of said conducting portions are so formed that no given conducting portion is overlapped with any adjacent conducting portion, or any portions of other electrodes, in the direction of the thickness; and wherein said piezoelectric material has such an effective Poisson\s ratio that the piezoelectric material is not usable to trap the fundamental mode energy of the thickness extensional vibration mode by lowering the resonance frequency.