| 摘要 |
PURPOSE:To obtain fluoride optical fiber contg. no scattered body and causing low light loss, by heat-treating a sublimable and a nonsublimable glass raw material independently to each other in dry halogen-contg. gaseous atmosphere, and drawing to wire after vitrifying by melting. CONSTITUTION:A sublimable raw material (e.g,. ZrF4) is heated at 200-800 deg.C in dry gaseous atmosphere contg. halogen contg. at least one of HF and F2, obtd. thus a raw material (A) to be treated. Then, a raw material (B) to be treated is obtd. by heating the chloride, etc. of a nonsublimable raw material (e.g. BaF2) at 200-1,100 deg.C in dry gaseous atmosphere contg. halogen contg. at least one of HCl and Cl2. Thereafter, the solid batch of the fluoride glass raw material obtd. by mixing the component (A) with (B) is melted at about 850 deg.C for about 2hr, and the fluoride glass is obtd. by cooling quickly the batch. Finally, the glass is drawn and optical fiber is formed. |
