Patent GB-1003861-A (GB)
Title: Improvements in optical or electrical energy-conducting components formed of fiber elments and method of making same
IPC: C03B37/028
Filed: 1962-10-05
Abstract: An optical or electrical energy-conducting component is formed of a plurality of long and thin fibres, each having one or more core sections formed of energy conducting material, each core section being surrounded by an integrally related relatively thin cladding of material adapted to prevent at least the major portion of energy being conducted lengthwise of the core section from passing outwardly through the sides of the fibres, the fibres being arranged in substantially parallel side-by-side relationship as longitudinal elements of a hollow elongated tubular structure and fused together as a unit.  A tubular structure 42, Fig. 7, composed of mono- or multifilament fibres 30 each having a core of glass coated with glass of a different refractive index, is formed as in Fig. 3 by positioning the fibres 30 with ends held against a shoulder 50 of an adaptor 44 by a band 54 and extending over a plug 46 adjustably positioned over an apertured plate 52 at the entrance to a furnace 64, the aporture 66 of which tends to press the fibres 30 into engagement with each other.  The adaptor 44 is on an arm 56 threaded on a screw 58 rotated in a bracket 60 by a pulley and belt 62 so as to lower the adaptor 44 and therefore pass the fibres 30 through the furnace 64 to fuse them together. The movement downwardly is initiated by fusing the lower ends at 82, inserting a glass rod bail and pulling till the assembly can be clamped <PICT:1003861/C1/1> in a chuck 84 which is then lowered on a screw 88 either at a slightly greater rate than the lowering of adaptor 44 to join the fibres 30 or at a greater rate to reduce the diameter of the tube 42.  The rate of drawing may also be varied to give a tapered tube 42, similar to that shown in Fig. 19.  The tube 4211 may also be formed as in Fig. 16 by positioning the fibres 30 between a core 98 and mould elements 94, 96, a space 104 between them allowing pressing of the fibres 30 together when the mould is introduced into a furnace and the fibres 30 fuse together.  In either method, hexagonal tubes or other shaped tubes may be formed.  As shown in Fig. 7, the tube 42 is then packed with further fibres 301 similar to fibres 30 and drawn downwardly through a furnace in apparatus similar to Fig. 3 with the additional feature that the upper ends are connected to a vacuum pump to remove the air between the fibres 301 and the whole drawn downwardly to fuse and draw out the tube 42 and fibres 301 to a structure 132, Fig. 13, and a number of such structures 132 can be joined together under heat and pressure to form a plate 134, which may form the face plate of a cathode-ray tube.  In Figs. 19-22, the structure 1321 is shown as being drawn out at controlled rates to give tapered sections 138, a number of which may be fused together and cut to give plates 142, used here as the face plate of a cathode-ray tube.  Tubes 42 of differing sizes may be telescoped and fused together to give a structure having a concentric pattern of fibres 30.  Reference has been directed by the Comptroller to Specifications 895,368 and 925,335.