Improved mirror systems for high resolution ultrasonic imaging.

High resolution ultrasonic imaging in a water bath, for example breast imaging, demands a transducer of large aperture. Such an aperture is most easily achieved by the use of mirrors. Previous such mirror systems suffered problems from reverberations between and within their component parts. Changes in the design of the system, and the use of thin metal reflectors, reduce these reverberations to an acceptable level. There is no sacrifice in the focusing performance, and losses in the system are minimized.