Energy lock-in-type flat piezoresonator sets specific thickness between respective internal electrodes and piezoelectric layers and between internal electrodes

摘要

Internal electrodes (3-6) are distributed inside piezoelectric housing (2). An alternately reversed polarity electric field is impressed on electrodes between piezoelectric layers (2c,2d). The thicknesses (D1,D2) between respective internal electrodes (3,6) and piezoelectric layers (2c,2d), are set to specific value and thickness (D) between internal electrodes (3,4) is said to a specific value. When number N of internal electrodes is 3, then 0.5 <= D1+D2 and 2D <= 0.80 and when N=4, 2D <= 0.90 and when N=5 2D <= 1.00. Independent claims are also included for the following: (a) Ladder type filter; (b) Piezoelectric resonance component