| 摘要 |
1477171 Light guides SUMITOMO ELECTRIC INDUSTRIES Ltd 12 June 1974 [13 June 1973] 26173/74 Heading G2J An optical transmission fibre comprises an optical fibre which is already suitable for optical communication and which is already capable of transmitting light over long lengths, e.g. having core 1 and cladding 2, surrounded by at least one layer 6 of a composition comprising a thermoplastic resin having a functional group in the molecule. Layer 6 protects and reinforces the fibre. The preferred thermoplastic resin is a polyamide but other examples are a polyester; an ethylenevinyl acetate copolymer; an ethyene-acrylic acid copolymer and an ionomer resin. The composition may be extruded on to the optical fibre or may be applied in a dispersion or solution. In a review of the known art the following types of fibre are described with reference to Fig. 1:- (a) "Ordinary" fibre; (b) Clad multi-mode fibre; (c) Clad Single-mode fibre; (d) O-guide type fibre; (e) Self-focusing fibre and (f) Single material type fibre. For (b) and (c), core 1 and cladding 2 may both be glass; both plastics; 1 of plastics and 2 of glass; 1 1 of glass and 2 of plastics; 1 of liquid and 2 of glass or 1 of liquid and 2 of plastics. For (d) 3, 4 and 5 may be glass, plastics or liquid. For (e) plastics or quartz glass are used. |
