Novel high performance scattering materials for use in energy saving light fittings and skylights based on polymer pigmented with polymer

摘要

Simple quantitative performance criteria are developed for translucent materials in terms of hemispherical visible transmittance, and angular spread of transmitted luminance using a half angle. Criteria are linked to applications in luminaires and skylights with emphasis on maximising visible throughput while minimising glare. These basic criteria are also extended to angle of incidence changes which are substantial. Example data is provided showing that acrylic pigmented with spherical polymer particles can have total hemisphercial transmittance with weak thickness dependence, which is better than clear sheet, while the spread of transmitted light is quite thickness sensitive and occurs over wider angles than inorganic pigments. This combination means significantly fewer lamps can achieve specified lux levels with low glare, and smaller skylights can provide higher more uniform daylight illuminance.