| 摘要 |
PURPOSE:To provide the titled glass having excellent infrared transmittance and high heat-resistance, and suitable as an optical communication fiber, etc., by mixing PbF2 having no absorption in infrared region with AlF3 and YbF3 at specific molar ratios, and vitrifying the mixture. CONSTITUTION:The raw materials such as PbF2, AlF3, and YbF3, etc. are weighed in a manner to give a glass composed of 30-60mol% PbF2, 10-50% AlF3 and 5-55% YbF3, and the materials are crushed and mixed. The mixture is melted at about 1,000-1,200 deg.C, and formed in the form of the objective infrared-transmission glass by processes such as casting, roll-out, pull-up, pull-down process etc. To prevent the inclusion of moisture from atmosphere into the glass, it is preferable to carry out the melting in a dried inert gas atmosphere such as argon, helium, etc. or bubbling the molten glass with an active gas such as F2, Cl2, etc. |
