This book has been prompted by our des ire to share with others our apprecia tion of the harmony and beauty in a particular sphere of modern optics known as "optical phase conjugation". Practical applications of the phase conjugated wave are likely to be far-reaching. Optical phase conjugation (OPC) combines in itself aesthetic and pragmatic attractiveness, a synthesis that has made OPC a subject of general attention. The figure presents the ap proximate rate of publications (number of articles per year) on OPC in the world literature for recent years, the lower curve denoting the work carried out in the USSR. The efforts of a large unofficial international collective have yielded an impressive result. 150 100 50 1975 1980 At present, the physical pro ces ses underlying various OPC methods are quite understandable, and it is the physics of OPC to which our book is devoted. Practical and scientific applications of phase-conjugated waves, which are of no less interest, have been touched upon in short, as major achievements in this sphere are a matter of the future. Today there are two main methods of OPC: i) by backward stimulated light scattering, ii) by four-wave mixing. Naturally, much attention is given to these methods in our book which, after the introductory Chap. 1, can be divided into two almost independent parts - Chaps. 2 - 5, and Chaps. 6 - 8.

A complete review of the state of the art of phase conjugate lasers, including laser demonstrations, performances, technology and selection of the most important class of nonlinear media. * Emphasizes the basic aspects of phase conjugation. * Chapter authors have all made major contributions to their subjects.

This volume presents results from fundamental research on the phenomenon of phase conjugation of laser emission discovered at the Physics Institute of the Academy of Sciences during stimulated scattering in hypersound, and with four-wave interaction in a wavelength range from the visible through the mid-infrared. Fundamentally new optical designs and methods of controlling laser emission are proposed and tested experimentally on the basis of this effect.

Principles of Adaptive Optics covers the basic principles of optics, wavefront sensing, controls, and wavefront correction that encompass the specialized field called adaptive optics. This book is composed of eight chapters that summarize the fundamental technology developments and the basic understanding of the various disciplines used in adaptive optics. After briefly reviewing the history, background, and developments of adaptive optics, this book goes on discussing the many sources of phase aberrations addressed by adaptive optics systems, such as linear effects due to turbulence, optical manufacturing, and misalignments, as well as errors that result from nonlinear thermal effects and fluid properties. The subsequent chapter deals with the performance enhancing role of adaptive optics systems in various disturbances. Other chapters describe the wavefront sampling, sensing, and correction subsystems. The concluding chapters explore the fundamental principles behind the adaptive optics control system and present summary expressions to determine the basic system parameters of an adaptive optics atmospheric compensation system. Communication scientists and engineers will find this work invaluable.

Principles of Adaptive Optics describes the foundations, principles, and applications of adaptive optics (AO) and its enabling technologies. Addressing the fundamentals of AO at the core of new uses in biomedical imaging, communications, high-energy lasers, and astronomy, this fully revised and significantly expanded Fourth Edition:Contains all-new

This book appears at a time of intense activity in optical phase conjugation. We chose not to await the maturation of the field, but instead to provide this material in time to be useful in its development. We have tried very hard to elucidate and interrelate the various nonlinear phenomena which can be used for optical phase conjugation.