Patent ID: 7068895
Filing Date: 2006-06-27
Classification: C03B,G02B

Abstract:
1. A multimode optical fibre suitable for transmission rates equal to or higher than 1 Gigabit/sec manufactured according to a method that includes: i) supplying one or more glass forming precursors, and possibly a dopant, to a quartz substrate tube; ii) forming a plasma in the quartz substrate tube to bring about a reaction so as to form glass layers, which may or may not be doped, on an interior of the substrate tube; iii) collapsing the substrate tube obtained in ii) into a preform while heating, iv) drawing an optical fibre from the preform while heating, wherein the glass layers, which may or may not be doped, are deposited on the interior of the substrate tube in such a manner that separate layers are obtained after iii) and iv) in a region having a diameter of 10 μm at most in a center of an optical fibre that is finally drawn, wherein at least one of said separate layers has a cross-sectional surface area of 2 μm