Modular Light Transport System for Daylighting

A novel daylighting system is proposed in which three sizes of internally reflecting device are used to transmit daylight into buildings for illumination. The use of the three devices, light pipes, light rods and light fibres, in conjunction with one another will allow great flexibility in design and installation of daylighting systems. Light pipes are an established daylighting device with diameters of 200-1000mm, light rods are a recently developed light transport device of 25-150mm diameter and light fibres are 1-3mm diameter glass optical fibres. The light fibre system uses a tracking concentrator for light collection, the other devices are static. Light pipe and light rod systems were built and tested and were found to transmit at a similar efficiency. The light fibre system is still under development and is analysed theoretically. The combined use of these devices should allow daylighting in a greater range of buildings than previously. Building occupants would benefit from natural light and the reduction of pollution and expense associated with the use of electric lights.