British Telecommunications Public Limited Company

British Telecommunications Corporation

Stephen R Mallinson

Colin A Millar

Michael Charles Brierley

Peter Healey

Stephen Hornung

Jonathan S Harper

William P Urquhart

A method of forming low loss splices between single-mode optical fiber ends involves taking prepared fiber ends and aligning the one with the other by inserting them into opposite ends of the bore of a ferrule, and fusing the fiber ends together by applying thermal energy thereto by means of an aperture in the wall of the ferrule. Splices prepared in this way have losses of less than 0.5 dB. The use of a precisely dimensioned ceramic ferrule enables the use of splicing apparatus which does not incorporate means for 3-dimensional micromanipulation.

Optical fibre splice

Endface assessment

Optical space switch

Optical switch

Optical devices

Optical device

Optical coupler

A micro-optic lens is formed by making a lens element (20) having a length less than the required lens length. Adhesive (22) is attached to the rear of the lens element and a glass plate (21) attached to the adhesive. An optical fibre (26) is located against the plate (b 21), light is transmitted along the fibre, the beam emerging from the element (20) is sensed and the axial position of the plate (21) adjusted until the beam is sensed to be collimated. The adhesive (22) is then cured.

Microlens manufacture

Dielectric optical Fabry-Perot waveguide device and method for making

Fabry-perot interferometer

An optical fibre termination is machined to provide a locating surface having improved concentricity with a therein-mounted optical fibre by more accurately locating the optical fibre at the rotational center of a machining tool. Light transmitted through the optical fibre is monitored while the termination is adjusted, in response to such monitoring, to accurately coincide with the rotational machining axis.

Optical fibre terminations and methods of and apparatus for making

An optical fibre connector to connect two optical fibres comprises a ferrule secured to each fibre end, and a clamping sleeve of shape memory effect metal to align and clamp the ferrules. The shape memory effect metal is selected and trained to expand on heating above its transformation temperature. The bore of the clamping sleeve is arranged to make an interference fit with the ferrules when below the transformation temperature, and a clearance fit when above the transformation temperature. An elastic titanium alloy compression sleeve surrounding the clamping sleeve provides for long-term integrity of the connector and reinforces the clamping action of the clamping sleeve when below its transformation temperature.

Temperature sensitive releasable optical connector

Growing community of inventors

Ipswich, United Kingdom

Stephen R Mallinson