The gradual transition from blue-enriched to neutral white light for creating a supportive learning environment. (August 2020)

• Record Type: Journal Article
• Authors: Choi, Kyungah; Suk, Hyeon-Jeong
• Is Part Of: Building and environment. Volume 180(2020)
• Publication Date: 2020-08
• Subjects: Lighting control -- Learning environment -- Education -- Visual distraction -- Blue-enriched white light -- Correlated color temperature; Buildings -- Environmental engineering -- Periodicals; Building -- Research -- Periodicals; Constructions -- Technique de l'environnement -- Périodiques; Electronic journals; 696
• DOI: 10.1016/j.buildenv.2020.107046
• Languages: English
• ISSNs: 0360-1323

Abstract

Abstract: This study aims to deliver an ambient lighting control scenario that helps to maintain circadian entrainment as much as possible while supporting the cognitive performance of students. Two empirical studies were conducted. The first was a visual experiment to identify a setting that would provide smooth control of the lighting color temperature, taking into account the visual sensitivity of the human eye. Based on the results, a color temperature reduction from a 6500 K blue-enriched white light to a 5000 K neutral white light at a rate of 5 K/s was suggested. The second experiment investigated the effects of the suggested lighting transition on different aspects of students' performance, comparing the controlled (blue-enriched white to neutral white light), constant (neutral white light), and lights-off conditions. The level of concentration and arousal, as measured by brain and heart activity, respectively, was highest with the controlled lighting scenario. However, these effects were not reflected in the subjective assessments and the n-back task score. Taken together, the results demonstrated that a gradual lighting transition in which the blue-enriched white light changes into neutral white light could be beneficial in an educational context. Although there is still much to be learned about ambient lighting control, the results of this study may inspire and inform architects and designers, thereby facilitating the creation of better learning environments. Highlights: Gradual transition from blue-enriched to neutral white light could benefit students. Gradual color temperature reduction promotes students' learning without distraction. CCT reduction from 6500 K to 5000 K at 5 K/s can avoid perceivable distraction. Timed control of tunable white LED increases level of concentration and arousal.