D. S. Ballantine - Acoustic Wave Sensors. Theory, Design, & Physico-Chemical Applications

Modern Applications of Acoustics is a series, that will, in the hopes of the editors, present the most exciting developments in the applications of acoustics that have emerged in the past few decades. This first seven-author volume, which was already nearing publication when the series was conceived, is an auspicious beginning. It can be argued that all living entities have their own built-in biological acoustic sensors, be they aural or tactile, whose sensitivity, in some instances, is at the optimum signal-to-noise level. For instance, it is known that if the human ear were any more sensitive, Brownian noise would mask the intelligibility of perceived sound. It is possible that the sound emitted by crackling dry leaves and twigs may be the first artificial sensors devised by humans for detecting game or intruders. The sensors described in this volume avail themselves of the most modern microphotolithographic techniques, and use sophisticated signal processing techniques that could not be achieved without the use of the formidable power of modern computers. But, the germinal ideas are the product of human ingenuity.

The editors envision that future volumes will be authored by scientists and engineers who are internationally recognized in their fields as experts and who have made major contributions to the advancement of their areas. The series will include volumes that may be prepared by a single author, a few co-authors, or in the instance of emerging fields, the required expertise may best be harnessed by a guest editor who then will solicit contributions from many experts in narrower subfields.

At present the editors are actively pursuing the publication of volumes in thermoacoustic engines, resonant ultrasonic spectroscopy, modern architectural design, active noise suppression, biological and industrial flow detection, nondestructive evaluation, underwater detection, acoustic tissue characterization, sonoluminescense, and more.

The editors dedicate this series to their thesis advisor and mentor, Professor Isadore Rudnick.

Richard Stern and Moises Levy

Precise measurement tools are necessary parts of most successful scientific and engineering enterprises. The sensing devices that we consider in this volume are such tools, capable of measuring physical, chemical, and biological quantities. What they have in common is that they all employ acoustic waves in their operation. The purpose of this introductory chapter is to provide an overview of these devices, and to answer the question: why use acoustic sensors?