INFLUENCE OF TECHNICAL PARAMETERS OF LED INDIRECT LIGHTING INSTALLATIONS ON ILLUMINATION PARAMETERS

In this paper, we present the analysis of the influence of technical parameters of the examined indirect lighting installation on its utilization factor and lighting uniformity. Indirect lighting installations using LEDs were studied first through simulations and then through empirical measurement in a model. Selection of the surface reflectance coefficients in the examined space was found to be critical. It was demonstrated that an indirect lighting installation meeting all standard requirements may feature a utilization factor of almost 50% when light-colored surfaces are used, but only 20% when surfaces with the minimum reflectance coefficients are used. The utilization factor observed empirically in the model and obtained in computer simulations differed by only 3%. The measured and calculated illuminance uniformity values were also very similar and high, exceeding 0.79. Studies indicate that even the high placement asymmetry of LEDs does not cause substantial loss in efficiency and illuminance uniformity.