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非均匀厚度的压电传感器能大大增加传感器的频带宽度。较宽的频带有利于提高声纳和超声波成像设备的准确度。普通的压电传感器是一块晶体片,在晶体的两个平行面上镀有金属膜。当两层金属膜上加有交变的电位时晶体迅速地收缩和扩胀,因此它能向材料四周发射压缩的弹性波。如果晶体的两个面是平行的,则晶体只能在很窄的频率范围内谐振,出此而在介质周围建立的超声波也只有同样窄的频率范围。新设计的传感器则不同,晶体的两个面不是平行的,例如一个面是平面,另一个面是凹面。这样设计
Non-uniform thickness of the piezoelectric sensor can greatly increase the sensor’s bandwidth. The wider frequency band helps to improve the accuracy of sonar and ultrasound imaging equipment. An ordinary piezoelectric sensor is a piece of crystal that is coated with a metal film on two parallel faces of the crystal. When an alternating potential is applied to the two metal films, the crystal shrinks and expands rapidly so that it can compress the elastic waves around the material. If two faces of a crystal are parallel, the crystal resonates only in a very narrow frequency range, so that there is only the same narrow range of frequencies for the ultrasonic waves built around the medium. The newly designed sensor is different, the two faces of the crystal are not parallel, for example, one plane is a plane, the other is concave. This design