An innovative light collimator designed to enhance the amount of light captured and transported through tubular skylights.
About
Brief Description Interest in installing daylighting systems within buildings has increased over the past decade. This is primarily motivated by savings experienced through reduced energy costs and also the health benefits natural light offers. There is increasing evidence that Exposure to natural light in schools and office buildings provides positive health benefits through its effects on mood, alertness, metabolism and it also increases performance and productivity. In children it is most important for growth as well. Tubular skylights are one such daylighting system. They are one of the most commercially available and affordable devices to capture and transport daylight into buildings. However they experience the drawback of typically delivering low illuminance in rooms. Researchers at Stellenbosch University have addressed this drawback by developing an innovative light collimator designed to enhance the amount of light captured and transported through tubular skylights. The light collimator has been shown, for example, to enhance light produced by a skylight from 178 lux to up to 370 lux. This is the amount of light that is adequate for advanced tasks such as reading in a classroom or library. Target Market Manufacturers of skylights Architectures Building owners Construction companies Value Proposition/Benefits An improved light tube design that offers more illuminance in the building for substantial energy savings and increasing occupants’ productivity and comfort. Competitive Advantage The configuration of the collimator increases the illuminance above 370 lux and helps to distribute the light evenly in the work space compared to the conventional light pipes that produce less than 200 lux. Technical Description The non-imaging optical system with the collimator applies a principle of edge-ray efficiency and has shown that a rough surface reflector is able to get a uniform spatial light distribution with average light levels of 370 lux from 9h00 to 16h00. Innovation Status A South African provisional patent (no. 2014/07659) has been filled.