A scanning acoustic microscope, using the design we have previously described, can now be routinely operated at a frequency of 1 GHz with a corresponding resolution of nearly 1 micron. Operating in transmission a number of biological samples have been imaged. With this high resolution, variations in the elastic properties within individual cells can be seen. Moreover, clear distinctions have been demonstrated between the acoustic images and corresponding optical micrographs. Several alternative imaging modes have also been demonstrated with this instrument. One of these is a phase contrast technique in which the phase of the output signal is compared directly to the phase of the input signal. Another mode is reflection imaging which allows specimens on thick substrates to be viewed. This technique has been applied profitably to an investigation of integrated circuits. (Author).

In 1992 Acoustic Microscopy was published by Oxford University Press, in the series of Monographs on the Physics and Chemistry of Materials. Reviews appeared in the Journal of Microscopy [169 (1), 91] and in Contemporary Physics [33 (4), 296]. At the time of going to press, it seemed that the field of acoustic microscopy had settled down from the wonderful developments in resolution that had been seen in the late seventies and the early eighties and from the no less exciting developments in quantitative elastic measurements that had followed. One reviewer wrote, "The time is ripe for such a book, now that the expansion of the subject has perceptively slowed after it was detonated by Lemons and Quate. " [A. Howie, Proc. RMS 27 (4), 280]. In many ways, this remains true. The basic design for both imaging and quantitative instruments is well-established; the upper frequency for routine imaging is the 2 GHz established by the Ernst Leitz scanning acoustic microscope (ELSAM) in 1984. For the most accurate V(z) measurements, the 225-MHz line-focus-beam lens, developed at Tohoku Univer sity a little before then, remains standard. The principles of the contrast theory have been confirmed by abundant experience; in particular the role of surface acoustic waves, such as Rayleigh waves, dominates the contrast in most high resolution studies of many materials.

Novel physical solutions, including new results in the field of adaptive methods and inventive approaches to inverse problems, original concepts based on high harmonic imaging algorithms, intriguing vibro-acoustic imaging and vibro-modulation technique, etc. were successfully introduced and verified in numerous studies of industrial materials and biomaterials in the last few years. Together with the above mentioned traditional academic and practical avenues in ultrasonic imaging research, intriguing scientific discussions have recently surfaced and will hopefully continue to bear fruits in the future. The goal of this book is to provide an overview of the recent advances in high-resolution ultrasonic imaging techniques and their applications to biomaterials evaluation and industrial materials. The result is a unique collection of papers presenting novel results and techniques that were developed by leading research groups worldwide. This book offers a number of new results from well-known authors who are engaged in aspects of the development of novel physical principles, new methods, or implementation of modern technological solutions into current imaging devices and new applications of high-resolution imaging systems. The ultimate purpose of this book is to encourage more research and development in the field to realize the great potential of high resolution acoustic imaging and its various industrial and biomedical applications.

The combination of atomic force microscopy with ultrasonic methods allows the nearfield detection of acoustic signals. The nondestructive characterization and nanoscale quantitative mapping of surface adhesion and stiffness or friction is possible. The aim of this book is to provide a comprehensive review of different scanning probe acoustic techniques, including AFAM, UAFM, SNFUH, UFM, SMM and torsional tapping modes. Basic theoretical explanations are given to understand not only the probe dynamics but also the dynamics of tip surface contacts. Calibration and enhancement are discussed to better define the performance of the techniques, which are also compared with other classical techniques such as nanoindentation or surface acoustic wave. Different application fields are described, including biological surfaces, polymers and thin films.

This only and up-to-date monograph on this versatile method covers its use in a range of applications spanning the fields of physics, materials science, electrical engineering, medicine, and research and industry. Following an introduction, the highly experienced author goes on to investigate acoustic field structure, output signal formation in transmission raster acoustic microscopes and non-linear acoustic effects. Further chapters deal with the visco-elastic properties and microstructure of the model systems and composites used, as well as polymer composite materials and the microstructure and physical-mechanical properties of biological tissues. A handy reference for materials scientists, electrical engineers, radiologists, laboratory medics, test engineers, physicists, and graduate students.