This book highlights time reversal acoustics, techniques based on the symmetry properties of acoustic fields. It has the unique feature that the first eleven chapters of the book are on the indepth studies of the theories of time reversal acoustics. The remaining chapters are on the four major applications of time reversal acoustics, together with their experimental setups and case studies: underwater communication, seismic exploration,nondestructive evaluation, and medical ultrasound imaging.. The gauge invariance approach to acoustic fields, proposed by the author in 2007, is confirmed by the successful fabrication of acoustical metamaterials and the applications of time reversal acoustics to superresolution. The book also presents groundbreaking applications of time reversal acoustics to underwater communication technology and the application of metamaterials to time reversal acoustics.

This book highlights the symmetry properties of acoustic fields and describes the gauge invariance approach, which can be used to reveal those properties. Symmetry is the key theoretical framework of metamaterials, as has been demonstrated by the successful fabrication of acoustical metamaterials. The book first provides the necessary theoretical background, which includes the covariant derivative, the vector potential, and invariance in coordinate transformation. This is followed by descriptions of global gauge invariance (isotropy), and of local gauge invariance (anisotropy). Sections on time reversal symmetry, reflection invariance, and invariance of finite amplitude waves round out the coverage.

This book highlights the acoustical metamaterials' capability to manipulate the direction of sound propagation in solids which in turn control the scattering, diffraction and refraction, the three basic mechanisms of sound propagation in solids. This gives rise to several novel theories and applications and hence the name new acoustics. As an introduction, the book mentions that symmetry of acoustic fields is the theoretical framework of acoustical metamaterials. This is then followed by describing that acoustical metamaterials began with locally resonant sonic materials which ushered in the concept of negative acoustic parameters such as mass density and bulk modulus. This complies with form invariance of the acoustic equation of motion which again exemplifies the symmetry property of acoustic fields.

This book highlights the acoustical metamaterials' capability to manipulate the direction of sound propagation in solids which in turn control the scattering, diffraction and refraction, the three basic mechanisms of sound propagation in solids. This gives rise to several novel theories and applications and hence the name new acoustics. As an introduction, the book mentions that symmetry of acoustic fields is the theoretical framework of acoustical metamaterials. This is then followed by describing that acoustical metamaterials began with locally resonant sonic materials which ushered in the concept of negative acoustic parameters such as mass density and bulk modulus. This complies with form invariance of the acoustic equation of motion which again exemplifies the symmetry property of acoustic fields.

This book highlights the theories and applications of quantum acoustical imaging which can be considered as a part of quantum technology. It starts with the theories and background principles of this new field  in depth.The examples of some present forms of available acoustical imaging which can be considered as quantum acoustical imaging are given such as  ultrasonics in the terahertz range with the use of  optical transducers  for producing terahertz ultrasound and the theory of sound amplification by stimulated emission of radiation (SASER) and principles based on terahertz ultrasound. The SASER transducer is described, followed by the applications of SASER.Other examples of  quantum acoustical imaging are the atomic force acoustic microscope (AFAM) and the ultrasonic  force microscope.  The author’s personal inventions of quantum acoustical imaging are  a system based on phonons entanglement based on the quantum property of phonons entanglement and the quantum ultrasound diffraction tomography system.The advantage of quantum acoustical imaging is the defeat of the classical Rayleigh image resolution limit.  An unique feature of this book is that it has gone in depth into the quantum theories of acoustical imaging such as phonons entanglement,,superposition principle and the application of  transport theory.Quantum microphones and quantum transducers are also introduced with a final chapter on quantum image processing.

This book highlights the theories and applications of quantum acoustical imaging which can be considered as a part of quantum technology. It starts with the theories and background principles of this new field in depth.The examples of some present forms of available acoustical imaging which can be considered as quantum acoustical imaging are given such as ultrasonics in the terahertz range with the use of optical transducers for producing terahertz ultrasound and the theory of sound amplification by stimulated emission of radiation (SASER) and principles based on terahertz ultrasound. The SASER transducer is described, followed by the applications of SASER.Other examples of quantum acoustical imaging are the atomic force acoustic microscope (AFAM) and the ultrasonic force microscope. The author's personal inventions of quantum acoustical imaging are a system based on phonons entanglement based on the quantum property of phonons entanglement and the quantum ultrasound diffraction tomography system.The advantage of quantum acoustical imaging is the defeat of the classical Rayleigh image resolution limit. An unique feature of this book is that it has gone in depth into the quantum theories of acoustical imaging such as phonons entanglement,,superposition principle and the application of transport theory.Quantum microphones and quantum transducers are also introduced with a final chapter on quantum image processing.

This book highlights the symmetry properties of acoustic fields and describes the gauge invariance approach, which can be used to reveal those properties. Symmetry is the key theoretical framework of metamaterials, as has been demonstrated by the successful fabrication of acoustical metamaterials. The book first provides the necessary theoretical background, which includes the covariant derivative, the vector potential, and invariance in coordinate transformation. This is followed by descriptions of global gauge invariance (isotropy), and of local gauge invariance (anisotropy). Sections on time reversal symmetry, reflection invariance, and invariance of finite amplitude waves round out the coverage.

This book discusses the applications of signal and image processing in acoustical imaging. It first describes the basic tools involved - the 2D transform, fast Fourier transform (FFT) and applications, and deconvolution - before introducing readers to higher-order statistics, wavelets, and neural networks. It also addresses the important topic of digital signal processing, focusing on the example of homomorphic signal processing. The book then details the design of digital filters and array signal processing, and lastly examines applications in image processing: image enhancement and optimization, image restoration, and image compression.