In this paper, the design of a luminaire for badminton court illumination is demonstrated from concept through computer simulation, construction trials, on-site installation, comparison with simulations and, finally, evaluations of the illuminated environment before and after the installation of the luminaires. The luminaire is composed of two high-performance light-emitting diode lighting modules, volume scattering diffusers with a one-shot transmittance higher than 70% and a reflecting cavity with a reflectivity higher than 85%. The luminaire has three different exit faces forming three Lambertian-like light sources with low luminance so as to reduce glare to the players when looking at the flight of the shuttlecock. Under similar total electric power consumption, compared to the original traditional lighting, the average illuminance on the ground is enhanced by about 300% and the uniformity is obviously improved. A questionnaire was issued to players before and after the installation of the new light-emitting diode luminaires. The new installation gained much more positive responses for brightness, comfort and number of usable courts from the players than the old installation.

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A screen image synthesis (SIS) system is superior than the conventional methods in terms of high-speed measurement and low screen-cross-talk noise when used as a whole-field light-distribution meter. However, reflection signals cannot be measured using the conventional SIS system when it is used as a scattering meter. Furthermore, the conventional SIS system cannot be used to measure a large sample when it is used as an intensity distribution meter. In this study, we devised a rail-based SIS system as long as an image reconstruction algorithm. This would allow wholefield scattering light and intensity distribution measurements for various sample sizes. For this purpose, a versatile instrument was assembled by combining a whole-field intensity distribution meter and a whole-field scattering meter. The results of the experiments confirmed that the measuring time was drastically improved when the proposed instrument was used as a whole-field intensity distribution meter and a whole-field scattering meter. The high normalized cross correlation values of both measurements demonstrated the accuracy and feasibility of the proposed algorithm.