For the design of modern office environments, lighting is a central aspect. With regard to current practice, uniform illumination is most often applied in interiors. In this paper, however, further aspects of a more individual approach are investigated, that deliberately violate the usual demands for uniformity by explicitly considering task-related, emotional and psychological effects of lighting. For this purpose, two independent experiments were conducted in an office mock-up setting exploring the impact of spatially variable, non-uniform light distributions on the users’ illumination preferences for the accomplishment of a given task. In the first experiment, three predefined illumination settings wererated by a group of naïve observers. Although the respective light distributions differed in their spatial characteristics, no significant differences were found in the rating scores. In addition, these variations showed no significant effect on the users’ preferred position of task performance. In the second experiment, though, a clearly significant effect could be reported such that, once the users were granted control over the illumination settings, an explicit demand for locally increased illuminance levels at the position of task performance was observed. Furthermore, high rating scores of perceived lighting adequacy indicate the users’ general satisfaction with the degree of visual assistance provided by such a task-related illumination. 1. Boyce P.R., Veitch J.A., Newsham G.R., Jones C.C., Heerwagen J., Myer M., Hunter C.M. Lighting quality and office work: Two field simulation experiments// Lighting Research and Technology, 2006, # 38, pp. 191–223.
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• office lighting
• task-related light distributions
• user preference
• visual comfort
• room perception