| 摘要 |
PURPOSE:To obtain a piezoelectric bending vibrator with ease of support and having less spurious response by forming an interdigital electrode to one side of a square piezoelectric plate in parallel with a diagonal line and applying a DC voltage to the electrode so as to apply polarization processing. CONSTITUTION:The interdigital electrodes 2, 3 are constituted so as to be in parallel with the direction of a diagonal line of the square piezoelectric plate 1, and the electrodes are connected alternately to lead electrodes at a circumference section. A DC voltage is applied between the electrodes 2 and 3 so as to apply polarization in a direction at a right angle to the lengthwise direction of the electrodes. In the vibration through the application of an AC voltage to the electrodes 2, 3 with this structure, the driving force of the piezoelectric longitudinal effect and the piezoelectric lateral effect is applied additively, causing the saddle-formed vibrating mode having crossed node lines M-M' and N-N' and being in a vertical bending vibrations with opposite phase to each other on the diagonal lines A-B and C-D to be excited. Thus, the piezoelectric filter with ease of support and high quality is obtained. |
