In the last few years the subject of optical cornmunications has moved
rapidly from being a promising research area to a practical reality
already being installed and carrying traffic in trunk networks in many
countries. At the same time new applications for fibre technology are
emerging and are placing new demands on the system components. In
telecommunications there is a steady increase of interest in the use of
fibres for undersea cables, in local area networks and wideband links,
and a little further ahead the possibility of coherent communications
systems. With an optical carrier bandwidth of 200 THz, today's maximum
bit rates of the order of Gb s-l do not approach the limits of the
medium, and questions about the ultimate limits of optical
communications are already being asked. On a different front, the rapid
advance of fibre sensors, previously drawing heavily on the
communications technology, is becoming a major driving force in the
development of fibres and other components. This picture of dramatic
growth in optical technology gives rise to other phenomena. A profusion
of small companies mushrooms to meet the demands of specific market
areas, each such company formed around a nucleus of experienced
personnel from the established research groups. Multi-- nationals jostle
for position in the optoelectronics marketplace and price wars develop
as fibre costs fall. University groups expand with government and
industrial funding in attempts to maintain long-term research options
and produce trained personnei.
