WIDE-ANGLE TRANSDUCERS FOR REAL-TIME ULTRASONIC PROCESS TOMOGRAPHY IMAGING APPLICATIONS

This paper describes the design of wide-angle transducers for a real-t ime ultrasonic tomography system for objects in a liquid. The system e mploys reflection mode tomography to generate images of the objects. T he effect of the emission angle of the transducer on the quality of th e reconstructed image is investigated and transducers with wide emissi on angles have been constructed for this work. A transducer ring with a diameter of 100 mm and using 36 elements has been successfully devel oped for this project. The system uses a digital signal processor for the data acquisition and a network of parallel processors for the real -time image reconstruction. A description of the overall system is giv en and results captured in real-time using test objects are shown in t he form of images with a 100 x 100 pixel resolution. Reconstructed ima ges have been obtained with speeds of up to 55 frames per second. (C) 1997 Elsevier Science B.V.