Summary
This study documents a full year of real-world personal light exposure using the LightWatcher dosimeter worn on eyeglass frames during the day and wrist at night, revealing differences in light dose between working and non-working days across all seasons. The findings highlight the practical challenges and opportunities of continuous light monitoring, with implications for designing lighting interventions calibrated to actual human light exposure patterns rather than assumed ones.
Key Findings
- Measurable differences in light exposure were observed between working days and non-working days, suggesting behavioral and environmental context strongly shapes daily light dose.
- The LightWatcher captured UV, Blue, Green, Red, and Infrared spectral irradiances alongside activity and temperature across all four seasons over a full year of continuous wear.
- The study identified practical limitations of current dosimeter design and proposed hardware/software improvements for future circadian light monitoring tools.
Categories
Sleep & Circadian Health: Year-long personal light dosimetry captures real-world seasonal and behavioral variations in light exposure relevant to circadian entrainment.
The Science of Light: The LightWatcher device measures multiple spectral bands (UV, Blue, Green, Red, IR) plus activity and temperature, providing detailed characterization of personal light dose across contexts.
Author(s)
D Dumortier
Publication Year
2019
Related Publications
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- Phototransduction by retinal ganglion cells that set the circadian clock
- The mammalian circadian timing system: organization and coordination of central and peripheral clocks
- The twoāprocess model of sleep regulation: a reappraisal
- Melanopsin is required for non-image-forming photic responses in blind mice
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The Science of Light
- Phototransduction by retinal ganglion cells that set the circadian clock
- Color appearance models
- The mammalian circadian timing system: organization and coordination of central and peripheral clocks
- Diminished pupillary light reflex at high irradiances in melanopsin-knockout mice
- Melanopsin is required for non-image-forming photic responses in blind mice