| 摘要 |
PURPOSE:To suppress effectively all higher harmonic by forming the piezoelectric plate of a piezoelectric vibrator into a diamond and by setting one of angles made by two sides to a specific angle. CONSTITUTION:One of angles made by two sides of a diamond is set to theta; and when line A, line B, line C, line D and line E are shown as fundamental vibration 455kHz, tertiary higher harmonic 1.2MHz, fifth-degree higher harmonic 2.0MHz, outline vibration 650kHz, and bending vibration 300kHz respectively on the graph where angle theta is the horizontal axis and ratio dB of the antiresonance resistance to the resonance resistance is the vertical axis, almost all spurious vibration is suppressed for angle theta of 75-89 deg.. Consequently, if one of angles made by two sides of the diamond-shaped piezoelectric plate is set to approximately 75-89 deg., all higher harmonic can be suppressed effectively. |
