Ultrasonic Transducer Arrays Made from Composite Piezoelectric Materials

Abstract

A method for providing a curved composite ultrasound transducer of a relatively large size. A blank of piezoceramic material has its rear side reticulated with a series of relatively coarse grooves. The front side of the material is reticulated with a series of relatively deep fine grooves to provide a matrix of upstanding piezoceramic rods. The spaces between the rods on the front side of the blank are therefore filled with a curable polymeric resin (epoxy). The resin filling the blank spaces on the front side is partially cured. After partial curing, the blank is placed into a spherical compression mold and molded so that its front side is formed concave and its rear side convex. The resin is cured while holding the molded blank under pressure in the mold until the resin has cured. After curing, the blank is removed from the mold and the back side is ground away to provide a spherically curved transducer having a multiplicity of individual piezoceramic rods disposed in a matrix of cured resin.