Illuminance Distribution Variation with the Angle of Reflectors

In this paper, we fabricated angle-changable two-stage reflectors and measured the illuminance as a function of the angle of reflection plates. The illuminance of center areas could be controlled by changing the angle of upper reflection plates and the illuminated area expanded with reducing the angle of lower reflection plates. The bright spots could be moved using asymmetric structures of reflection plates. It was found that the distribution of illuminance matches well with the Gaussian distribution function. From the results of curve fitting, it was found that without reflectors, a half of the lights emitted from fluorescent lamp do not reach the working place. A simple model was suggested to explain the illuminance variation with the structure of reflector.