Task-related Luminance Distributions for Office Lighting Scenarios

Abstract

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.

Measurement of Circadian Effectiveness in Lighting for Office Applications

“…As for example described by Kobbert [101] for the automotive context, the required data to develop this kind of statistical models can be obtained by combining in situ eyetracking [102] with state-of-the-art object recognition algorithms in order to determine characteristic gaze behavior distributions of office workers for a typical office day, e.g., like in the present case, with a focus on display work. The availability of such contextdependent eye-tracking based gaze behavior models does not only help to perform more reliable and meaningful estimates of the circadian effectiveness of the lit working environment adopting the novel measurement approach proposed in this work, but may also contribute to the optimization of the respective luminaires' light distributions to match the specific, task-related visual needs of the office workers [13]. Their development will be part of our future research efforts.…”

“…When designing lighting solutions for the built environment, practitioners usually have to deal with lighting parameters that can be assigned to either of the following four categories [11,13]: (i) Light intensity, which represents the amount of light received by the occupants; (ii) Light spectrum, which determines the color quality, perceived chromaticity, and correlated color temperature (CCT) of an illumination; (iii) Temporal pattern, which includes the timing and duration of the light exposure; and (iv) Spatial light distribution, which is basically understood as the luminance pattern constituting the occupants' field of view.…”

A Field Study of Individual, Energy-Efficient, and Human-Centered Indoor Electric Lighting: Its Impact on Comfort and Visual Performance in an Open-Plan Office Part 1

“…However, ongoing research and advancements in lighting technology are driving the adoption of HCL in the design and operation of buildings. When designing lighting solutions for the built environment, practitioners typically need to consider lighting parameters falling into one of the four categories listed in [12,13]. For this purpose, the Circadian Stimulus (CS) metric, a physiologically relevant measure of circadian effectiveness in lighting, and the Equivalent Melanopic Lux (EML), referred to as CIE S 026:2018 [14], are commonly used metrics for assessing circadian lighting effects, measured in m-lux and lux, respectively.…”

Tackling Heterogeneous Color Registration: Binning Color Sensors

“…In addition to the aspect of energy saving, ergonomic considerations in lighting are becoming increasingly important. Modern, multi-channel LED systems offer a huge flexibility in providing dynamic patterns of light exposure throughout the day [ 20 ], which can be tailored to match the users’ specific needs in terms of circadian rhythm [ 21 , 22 , 23 ], task-related performance [ 20 , 24 , 25 ], and lighting preference [ 26 , 27 , 28 , 29 ]. With regard to an intelligent lighting control, sensor feedback may thus allow for an automated time- and task-dependent adaptation of corresponding light levels and spectra, while taking contributions from time-varying natural daylight sources into account.…”