| 摘要 |
PURPOSE:To obtain a definite high gain in broader wavelength area than that in the present circumstances by containing a specific amount of chlorine in a core part, in a optical wave guide of fluoride glass consisting of a ZBLAN- based fluoride glass and containing praseodymium (Pr) at least in the core part. CONSTITUTION:Fluorine as a constituent anion of a ZBLAN-based fluoride glass doped with Pr, concretely PrF is substituted with chlorine so as to contain 2-15mol% in a core part to prepare the objective optical wave guide. Thereby, wavelength area of signal light whose gain value is >=90% of the maximum gain value becomes broader than the wavelength range of 1300-1310mum in the present circumstances. For example, the ZBLAN-based fluoride glass containing Pr, concretely PrF3 and PbF2 is produced as follows. The chlorine concentration is controlled by substituting a part of BaF2 in the raw material with BaCl2. The substituted material is melted to prepare a rod for the core part. A pipe for clad is separately prepared by using ZBLAN-based fluoride glass doped with Hf, specifically HfF3 and the core part is inserted into the pipe for clad. |
