Technology allows humans to see with sound, (something that bats, whales, and dolphins can do unaided); and advances in that technology have produced sophisticated techniques that defy categorization into the three fundamental types of acoustic imaging systems: pulse-echo, phase-amplitude, and amp

How to produce images with sound has intrigued engineers and scientists for many years. Bats, whales and dolphins can easily get good mental images with acoustical energy, but humans have little natural ability for obtaining such images. The history of engineering and science, however, is an impressive demonstration that technological solutions can compensate, and then some, for deficiencies of nature in humans. Thus with the proper technology, we too can "see" with sound. Many methods involv- ing ultrasonic energy can be employed to enable us to do so. Few of these methods are at all...

The latest progress in acoustical holography and related research areas, generally involving imaging by means of acoustic waves, was discussed and treated in depth at the Fourth International Symposium on Acoustical Holography, held in Santa Barbara, California on April 10-12, 1972. This volume contains the proceedings of that symposium. As the papers presented here indicate, a num ber of startling advances have been realized in the state-of-the-art since publication of Volume 3 of Acoustical Holography. Progress has been partic ularly impressive in the field of acoustical imag ing. The...