Simplified digital synthesis of ultrasonic images

A new technique produces ultrasonic images of a plane orthogonal to an accessible surface by using information collected from a transducer scanning that surface in a straight line. This technique is comparable with existing methods, particularly computer-aided B-scan and single-line acoustic holography, but embodies considerable simplification in the processes of data collection and image construction. Despite the simplification, the technique is capable of resolution to wavelength order in all directions in the image; it has the capacity, unlike acoustic holography, to image specular reflectors and it suppresses spurious images caused by mode conversion. Demonstrations are presented of in vivo biological imaging and of imaging in water and steel, with image processing times of a few seconds by means of a microprocessor. Prospective improvements in microprocessor speeds and costs suggest potential for the new technique in both engineering and medicine.