Plastics optical fibers

DETAILED DESCRIPTION We claim: 1.
Plastic optical fibers comprising as a core component a polymer predominantly containing methyl methacrylate and as a cladding component a copolymer lower in the refractive index than the core component, the plastics optical fibers being characterized by performing conjugate spinning with use of the cladding component which is vinylidene fluoride-tetrafluoroethylene copolymer having incorporated therein 5 to 50% by weight of a polymer predominantly containing methyl methacrylate.
2.
Plastics optical fibers as defined in claim 1 in which the vinylidene fluoride-tetrafluoroethylene copolymer contains 10 to 40 mole % of tetrafluoroethylene.




Description:
This invention relates to plastics optical fibers and particularly to plastics optical fibers having outstanding light-transmitting property and comprising as a core component a polymer predominantly containing methyl methacrylate and as a cladding component a synthetic high molecular weight copolymer composition lower in refractive index than the core component.
Heretofore well known as plastics optical fibers are those which comprise as a core component a synthetic high molecular weight material excellent in transparency, such as polystyrene or polymethyl methacrylate and as a cladding component a synthetic high molecular weight material lower in the refractive index than the core component, the core and cladding components being concentrically assembled to form a composite optical fiber so that incident light introduced from one end of the optical fiber are subjected to total reflection and transmitted in lengthwise direction through the optical fiber.
In the manufacture of this kind of plastics optical fibers, consideration should be taken to minimize the factors, such as the absorption or scattering of light, which are responsible for reduction in amount of light rays transmitted through the optical fiber.
Optical fibers prepared by use of a synthetic high molecular weight material, namely plastics optical fibers, have the features of being lightweight, ductile and easy to be high in the numerical aperture, as compared with optical fibers produced from inorganic glass, but the plastics optical fibers have the disadvantage of large transmission loss as compared with the glass optical fibers