| 摘要 |
PHD.85-105 13 2.5.86 Method of manufacturing optical fibres. In the PCVD method glass is deposited in layers on the inner wall of a glass tube heated at a temperature between 1100 and 1300.degree.C by passing a reactive gas mixture through the glass tube from a gas inlet side at a pressure between 1 and 30 hPa while in the interior of the glass tube a plasma is reciprocated strokewise between two reversal points, after which the glass tube, after a quantity of glass corresponding to the optical fibre construction in view has been deposited, is made to collapse so as to form a solid preform from which optical fibres are drawn. The range of non-constant deposition geometry at the preform entrance, i.e. on the gas inlet side, is reduced in that the reciprocating movement of the plasma at the reversal point is interrupted on the gas inlet side. |
