Abstract
Some rare-earth ions, when incorporated into a suitable lattice, can upconvert infrared light into visible one. This upconversion phenomenon is attracting a great interest in the application of a blue wavelength laser excited by on infrared laser diode. Pr- or Tm-doped fluoride fiber glass is suitable for this purpose. The characteristics of these upconversion fluorescences were examined for these fiber glass in order to obtain the upconversion mechanism. An upconversion laser glass excited by the laser diode would be realized when an appropriate glass host is chosen.
