发明名称 |
Method of collapsing preforms for optical fibers |
摘要 |
<p>The present invention provides a method of preparing preforms for optical fibers. The invention allows one to remove or significantly reduce undesirable refractive index variations in the central portion of the optical fibers. The method of preparing the preform having a central duct includes the steps of a first collapsing step, an etching step and a second collapsing step. The first collapsing step reduces the size of the central duct without closing the central duct by heating the preform at a first preform collapsing temperature. A portion of the last deposited layer of the core glass layers is etched by flowing an etchant gas through the central duct at a lower temperature than the preform collapsing temperature. The preform is finally collapsed at a second collapsing temperature to close the central duct of the preform and form a solid rod.</p> |
申请公布号 |
EP1035083(A1) |
申请公布日期 |
2000.09.13 |
申请号 |
EP20000301788 |
申请日期 |
2000.03.03 |
申请人 |
SPECTRAN CORPORATION |
发明人 |
MAZZARESE, DAVID J.;MCMAHON, TIMOTHY F.;OULUNDSEN, GEORGE E.;OWSIANY, MICHAEL T. |
分类号 |
C03B37/018;(IPC1-7):C03B37/018 |
主分类号 |
C03B37/018 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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