The physical properties and characteristics of fluoride glasses suitab
le for the realization of optical fibers and planar waveguides are giv
en. The planar waveguide technology, novel for this type of material,
is presented with more details. Active properties of rare-earth doped
fluoride fibers are presented, especially for up-conversion visible fi
ber lasers, infrared fiber lasers, and fiber lasers and amplifiers for
telecommunication.