The Lighting Environment, Its Metrology, and Non-visual Responses

International standard CIE S 026:2018 provides lighting professionals and field researchers in chronobiology with a method to characterize light exposures respect non-visual photoreception responses. This defines five spectral sensitivity functions that describe optical radiation for its ability stimulate each of the α-opic retinal photoreceptor classes contribute effects humans via intrinsically-photosensitive ganglion cells (ipRGCs). The also recently published an open-access toolbox calculates all quantities ratios metrology photometric, radiometric photon systems, based on either measured (user-defined) spectrum or selected illuminants (A, D65, E, FL11, LED-B3) built into toolbox. For wide variety ecologically-valid conditions, melanopsin-based ipRGCs has been shown account responses, from shifting timing nocturnal sleep melatonin secretion regulating steady-state pupil diameter. Recent findings continue confirm photopigment melanopsin plays role visual may have significant influence brightness perception aspects spatial vision. Although knowledge concerning extent which rods cones interact driving is still growing, position statement used melanopic equivalent daylight (D65) illuminance preliminary guidance applying “proper at proper time” manipulate Further this approach awaited participants 2nd Workshop Circadian Neurophysiological Photometry (in Manchester, August 2019). new 026 enables traceable measurements formal, quantitative specification personal exposures, photic interventions designs. Here, we apply everyday sources including natural time series, range LED products and, using toobox, smartphone display screen. collection examples suggests ways variations content over day can be adopted strategies use support human health well-being.