| dc.description.abstract | In this era of human centric lighting, the development of LED technologies not only focus on raising luminous efficiency and lowering production costs, but also the development of intelligent lighting and the use of dimming technology in different situations to create desirable lighting environment. This study considers the working or reading behaviors of general public in the office, school, etc., and uses scientific methods to find the most comfortable and efficient lighting scenarios for users. In this thesis, we will use statistical methods to explore the subjective perception obtained from the questionnaire in four aspects: visual preference, visual fatigue, physical fatigue, and subjective reading performance. The flicker fusion frequency and reading efficiency will be used to indicate the objective visual fatigue and task performance.
There are two independent variables in this study, namely the correlated color temperature at three levels (3000K, 4500K, 5700K) and task illuminance at four levels (200 lux, 450 lux, 700 lux, 1000 lux). Upon completing the experiments with 36 participants, subjective and objective indicators were statistically analyzed. The indicators that are statistically significant will be used as the basis for the establishment of luminaire control model. The task performance in English character detection is the only significant factor in the objective assessments. The factors that are statistically significant in the subjective questionnaire assessments include: in visual preference the brightness perception, the color preference, the color perception (reddish or bluish) and the overall lighting preference; in visual fatigue the eye pain, blurred vision, difficulty in reading and the overall visual comfort; in physical fatigue the overall physical comfort; and in subjective reading performance the font recognition speed, reading speed, ease of concentration and work duration. After identifying the factors that are statistically significant, a luminaire control model for indoor working and reading activities is established based on these factors with user-adjustable weighting coefficients. A higher rating from the model implies a more satisfactory lighting environment. The location with the highest rating is the optimal operating point, and the suggested luminaire operating range is defined as the region within one standard error from the highest rating of the model. | en_US |