The emergence of fibre optics as a commercially viable technology oc-
curred barely ten years ago; in this time it has become an established
field with a variety of applications. This book has been written in an
attempt to review the entire field with an emphasis on the practical
applications of the technology. This approach has been adopted since it
was felt that there was a need for a work which could be referred to by
non -specialists in the field who were interested in, or who wished to
make use of, fibre optics. With this readership in mind, the theory has
been presented in as simple a manner as possible and emphasis has been
placed on the description of typical applications and the manufacturing
techniques of the technology. It is hoped that this mode of presentation
will en- able the reader to form an appreciation of both its advantages
and its limitations.