Abstract: The present disclosure provides a cooling material which comprises a first spectrally selective component that comprises particles. The particles are arranged for emission of radiation predominantly having a wavelength or wavelength range within an atmospheric window wavelength range in which the atmosphere of the earth has a reduced average absorption and emission compared with an average absorption and emission in an adjacent wavelength range. Consequently, the cooling material is arranged for emission of thermal radiation and absorption of radiation from the atmosphere within that wavelength range is reduced. The cooling material further comprises a second spectrally selective component having a property that distinguishes the second spectrally selective component from the first spectrally selective component and facilitates at least one desired function of the cooling material.

Abstract: The present disclosure provides an element for emission of thermal radiation. The element comprises particles arranged for receiving thermal energy and emitting at least a portion of the received thermal energy in the form of the thermal radiation. The thermal radiation predominantly has a wavelength or wavelength range within an atmospheric window wavelength range in which the atmosphere of the Earth has a reduced average absorption and emission compared with an average absorption and emission in an adjacent wavelength range whereby absorption by the element of radiation from the atmosphere is reduced.

Abstract: The present invention provides a method of fabricating a preform (10) for a microstructured optical fibre. The method includes providing at least one hole forming element (13) in a mold. Each hole forming element (13) is elongate and is composed of a polymeric material that stretches and reduces in thickness upon application of a tensile stress (such as a nylon line). The method also includes forming the preform material (12) around, and contiguous, with an external surface portion of each hole forming element (13). The method further includes applying a tensile stress to a portion (14) of each hole forming element (13) to locally thin a zone (18) of each hole forming element (13), the thinning resulting in local detachment of the zone (18) from the preform material (10). A length of the detached zone (18) increases while the tensile stress is applied leaving a tubular portion in the preform material (12) where the hole forming element (13) was attached.

Abstract: The present invention provides a cooling material which comprises particles that are arranged for generation of surface plasmon resonances. The surface plasmon resonances have a wavelength or wavelength range within an atmospheric window wavelength range in which the atmosphere of the earth has a greatly reduced average absorption and emission compared with the average absorption and emission in an adjacent wavelength range, whereby the cooling material is arranged for emission of thermal radiation associated with the generated surface plasmon resonances and absorption of radiation from the atmosphere is greatly reduced.

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 lighting system for an interior of a building and the like includes a stack (102) of fluorescent sheets for collecting and converting sunlight into concentrated light. The stack (102) is of a substantially rectangular prism shape having top and bottom surfaces, opposed side surfaces defining therebetween a width of the stack (102), and opposed end surfaces defining therebetween a length of the stack (102), wherein the length of the stack (102) is sufficiently greater than the width of the stack (102) such that its aspect ratio as herein defined is greater than 4.0. The lighting system also includes a flexible light guide (104) for channeling the concentrated light to a light emitting fitting for the interior of the building or the like. The light guide (104) is optically coupled by optical joint (103) with the stack (102) through one of the end surfaces of the stack (102).

Abstract: A lighting system for an interior of a building and the like includes a means (30) for collecting and converting sunlight into concentrated light. The collecting means (30) is optically coupled, preferably by way of optical joint (43), coupling means (44), and optical joint (45), to a channelling means (46), such as an optical cable, so that the concentrated light passes to the channelling means (46) and is channelled to a light emitting fitting for the interior of the building and the like.