Patent ID: 7183690
Filing Date: 2007-02-27
Classification: H01L

Abstract:
1. A piezoelectric vibrator comprising: a thin rectangular piezoelectric plate having two short edge surfaces and two long edge surfaces and two large planar face surfaces which plate has transverse resonant vibration modes parallel to its short edges and longitudinal resonant vibration modes parallel to its long edges and is formed with at least one localized protuberance on a planar face surface that is located in a neighborhood of a node of a vibration mode and increases the frequency of the vibration mode; and at least one electrode on each of the planar surfaces that is electrifiable to excite a vibration mode of the plate, wherein the at least one localized protuberance shifts a resonant frequency of at least one vibration mode of the plate with respect to the resonant frequency that characterizes the at least one vibration mode in the absence of the at least one protuberance.