Abstract: The present invention relates to a method of splicing together two optical waveguides, such as an optical fibre and a planar waveguide, or two optical fibres. The method involves the steps of etching a terminal end of an optical fibre in the manner so as to create a tapered core projection. Another optical fibre or waveguide has a complimentary recess etched therein. The projection and recess are placed together and the waveguides moved together to facilitate alignment of the respective cores of the waveguides. A tube etching method is utilised to create the projection.

Abstract: An asymmetric multi-mode fibre optic coupler is assembled from two or more multi-mode optical fibres of different core and cladding diameters but substantially equal cladding refractive indices. The fibres are selected so as to have substantially equal effective refractive indices for their respective highest-order cladding modes, at least in the fabricated coupler.

Abstract: Apparatus for fabricating a fused biconical taper fibre optic coupler includes a hollow furnace (12) having a longitudinal slot (50). Clamp units (14, 16) are provided to hold at least two suitably prepared optical fibres (8, 9) in intimate side-by-side contact. The clamp units are moveable by motors (18, 20) to relatively laterally move the fibres into and out of the furnace (12) through the slot (50). A power supply (60) heats the furnace (12) to in turn heat segments of the fibres therein while these segments are in intimate side-by-side contact to a temperature sufficient to cause the fibre segments to fuse together. Drawings devices (22, 24) associated with the clamp units (14, 16) longitudinally draw the heated fibres while in the hot furnace to cause each fused fibre to develop a biconical taper and so form a coupler.

Abstract: A method of fabricating a fused fibre optic coupler includes disposing two or more segments of optical fibre under longitudinal tension. The tensioned fibre segments are preheated to a temperature sufficient to soften the segments and thereby substantially relieve their tension by inelastic stretching of the segments. After the segments have cooled, the fibre segments are re-tensioned and then heated while in intimate side-by-side contact to a temperature sufficient to cause the fibre segments to fuse together.