Measurement of Circadian Effectiveness in Lighting for Office Applications
Sebastian Babilon,Sebastian Beck,Julian Kunkel,Julian Marcel Klabes,Paul Myland,Simon Benkner,Tran Quoc Khanh +6 more
TLDR
A novel methodological framework for spatially resolved light measurements is proposed that allows for an estimate of the circadian effectiveness of a lighting situation for variable field of view (FOV) definitions and is compared to standard spectral radiometry to validate the accuracy of the proposed approach.Abstract:
As one factor among others, circadian effectiveness depends on the spatial light distribution of the prevalent lighting conditions. In a typical office context focusing on computer work, the light that is experienced by the office workers is usually composed of a direct component emitted by the room luminaires and the computer monitors as well as by an indirect component reflected from the walls, surfaces, and ceiling. Due to this multi-directional light pattern, spatially resolved light measurements are required for an adequate prediction of non-visual light-induced effects. In this work, we therefore propose a novel methodological framework for spatially resolved light measurements that allows for an estimate of the circadian effectiveness of a lighting situation for variable field of view (FOV) definitions. Results of exemplary in-field office light measurements are reported and compared to those obtained from standard spectral radiometry to validate the accuracy of the proposed approach. The corresponding relative error is found to be of the order of 3–6%, which denotes an acceptable range for most practical applications. In addition, the impact of different FOVs as well as non-zero measurement angles will be investigated.read more
Citations
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A Randomized Controlled Trail for Comparing LED Color Temperature and Color Rendering Attributes in Different Illuminance Environments for Human-Centric Office Lighting
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Study protocol for measuring the impact of (quasi-)monochromatic light on post-awakening cortisol secretion under controlled laboratory conditions
TL;DR: The current work provides the study protocol for an ongoing research project that is intended to explore the spectral dependencies and to discuss measures of emotional state and cognitive functioning potentially related to the cortisol awakening response.
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