Piezoelectric array using parallel connected elements to form groups

Abstract

In an exemplary embodiment a transducer comb for an ultrasonic array or a compound scanner consists of a specifiable number of transducer elements joined together in a specific area formation, the width of each transducer element being smaller than its height. In the case of sonic heads of this type, given an optimum radiation or receiving power, respectively, the lateral resolution is to be significantly improved. This is achieved by a transducer element arrangement comprising a fine subsidivision of the transducer elements in such a manner that the width of each individual transducer element lies markedly below half the wavelength (.lambda./2) of the radiated, or received, ultrasonic waves, whereby, however, within the arrangement, in each instance, always a specified number of transducer elements of the fine subdivision is combined into a group through parallel-connection. The total radiation/receiving surface, including the intermediate spaces, of such a group is to correspond to at least approximately the active area of an individual element of conventional transducer element arrangements. In spite of a relatively high loss due to the fine division of the transducer, at least the same radiation efficiency as in the case of conventional transducer arrangements results with the group interconnection, whereby, however, the echo response is virtually free of transverse vibrations.