摘要 |
An elongate light conductor of circular or other cross-section is continuously produced by depositing, in a vacuum chamber, a powdered glassy (i.e. vitreous or vitrifiable) material upon the upper end of a descending rod of like material while training a stream of doping ions upon the same end. Vitrification may be assisted by an electron beam, also trained upon the powder-receiving rod end, and/or by thermal treatment of the rod leaving the vacuum chamber. The lower end of the rod is softened in a furnace from which a vitreous strand of reduced cross-section is continuously drawn through an orifice and wound upon a mandrel.
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