Chronotype
Definition:Chronotype describes an individual’s natural preference for the timing of sleep and daily activity (for example, “morning lark” or “night […]
Glossary terms
Circadian Rhythms
Definition:Circadian rhythms are natural, internal processes that repeat roughly every 24 hours, regulating the timing of physiological and behavioural functions.
Chronobiology
Definition:Chronobiology is the scientific study of biological rhythms and their regulation. These rhythms include circadian rhythms (around 24 hours), ultradian
Suprachiasmatic Nucleus (SCN)
Definition:The suprachiasmatic nucleus (SCN) is a small region of the brain located in the hypothalamus, directly above the optic chiasm.
Alpha-opic Irradiance (and Illuminance)
Definition:Alpha-opic quantities weight light according to the sensitivity of the eye’s five photoreceptors, as defined in CIE S 026. The
ipRGCs
Definition:ipRGCs (intrinsically photosensitive retinal ganglion cells) are a class of retinal cells that contain the photopigment melanopsin. They respond directly
Circadian Stimulus (CS)
Definition:Circadian stimulus (CS) is a metric developed by the Lighting Research Center (LRC) to estimate the acute melatonin-suppression response to
Human-centric Lighting
Definition:Human-centric lighting (HCL) is an approach to lighting that prioritises people’s needs across visual performance, comfort, wellbeing and biology. It
WELL Building Standard
Definition:The WELL Building Standard is a performance-based certification system for measuring, certifying, and monitoring features of the built environment that
CIE S 026
Definition:CIE S 026 is the international standard published by the International Commission on Illumination (CIE) that defines a system for