Reviewing the development of optical fibre lasers and amplifiers over the past few years, this book is a compilation of chapters written by several contributors. Chapter 1 presents an overview and an historical introduction to the field. Chapter 2 is theoretical and introduces the concepts of energy levels and of lasing. Chapter 3 then discusses the fabrication of rare-earth doped optical fibres whilst chapter 4 covers the spectroscopy of rare-earth dopants in these fibres. Chapter 5 emphasizes the practical aspects of the laser amplifier. Chapter 6 moves on to the operation of erbium amplifiers in optical systems and a comparison is made here with other alternatives amplifying devices. Chapter 7 reviews work on fibre laser oscillators made in silica fibre, while chapter 8 covers similar work using fluoride glass fibres, an alternative glass host. Chapter 9 describes Q-switching and mode-locking in fibre lasers, and finally chapter 10 examines future prospects for these devices and discusses potential developments such as distributed fibre amplifiers, soliton propagation and the general use of fibre lasers in optical sensors.

One of the most exciting prospects for optical fibres made from fluoride glasses is the possibility of providing long distance optical communication systems without the need for repeaters. This objective has stimulated much of the work into fluoride glasses over the past ten years, and has prompted the writing of this book. It has also emerged that fluoride fibres can transmit both visible and infrared energy (from about 0.5 to 5, urn) and that they have many applications outside the field of telecommunications. These include optical fibre sensors (particularly in remote infrared spectroscopy), laser surgery and fibre lasers. Several companies are now established in the field, and good quality fluoride fibres are available from sources throughout the USA, Europe and Japan. Moreover, the first commercial instruments based on fluoride fibres are finding their way to the market place and these fibres will undoubtedly form the basis of many more instruments yet to be developed. The work presented in this book represents the field both from an academic understanding of the materials and ways to convert them into fibre, and from a practical and commercial viewpoint. The principal author and some of the co authors are based at the British Telecom Research Laboratories in the UK."