Abstract: A light guide (1) formed from an unclad flexible polyurethane fiber produces significant side scattering (2) over distances of up to several meters. The polyurethane fiber is in the form of a solid fiber or a tube and may comprise light scattering particles. The polyurethane fiber may comprise a transparent flexible polyurethane UV resistant outer cladding. Embodiments include illuminated shoe laces, a power cord safety indicator, an illuminated dental suction tube and a dental curing tip.

Abstract: An optical illumination device (20) comprises a light guide (10) formed from an unclad flexible polyurethane fibre (12), which comprises a transparent polyurethane region (14) and an adjacent coloured polyurethane region (16). The device comprises at least one illumination module (22) coupled to at least one end of the light guide and the illumination module comprises at least one light source (24) for illuminating the light guide.

Abstract: The invention relates to side-scattering light guides that generally comprise a core of transparent optically homogenous material seeded with diffuser particles. The light guide also comprises an optically transmitting sheath, having a lower refractive index than the core, surrounding and in contact with the sides of the core to prevent any light being transmitted along the core from escaping through the core's sides. In general, the diffuser particles impart only a small deviation to light rays incident upon them, and are distributed to scatter light being transmitted along the core so that at least some of the scattered light exits the sides of the core. A diffusing jacket is arranged to intercept scattered light exiting the sides of the core.

Abstract: The invention relates to a light emitting device consisting of one or more light sources coupled to a light guide containing diffuser particles having a refractive index close to the refractive index of the core of the light guide. The diffuser particles cause a scattering of the light emitted from the light sources so that light emitted from the light emitting device has colour variation imperceptible to the human eye and small and gradual variations in intensity.

Abstract: A side scattering light guide (10) for emitting light comprises a substantially transparent polymer core (12) surrounded by a transparent or translucent polymer cladding (14). The core (12) includes a light scattering additive (20) arranged to scatter light within the core so that at least some of the light passes through the cladding (14) to be emitted from the light guide (10). The light scattering additive (20) yields a high ratio of forward to backward scattering and is preferably in the form of diffuser particles. The type, density, concentration and/or refractive index of the light scattering additive may be selected to achieve the desired side scattering characteristics. A method of manufacturing the side scattering light guide (10) is also disclosed.

Abstract: A method of manufacturing light guide by filling a polymer tube with a monomeric mixture then pressurising and heating the full length of the polymer tube to initiate and maintain polymerisation in the tube. An apparatus for performing the method is also described in which the polymer tube is placed in a reaction vessel and a temperature controlled fluid is circulated to regulate the temperature in the vessel.