Wearable devices for circadian lighting: Spectral, spatial, photometric, melanopic, and thermal performance of dosimeters

Wearable devices for circadian lighting: Spectral, spatial, photometric, melanopic, and thermal performance of dosimeters | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Wearable devices for circadian lighting: Spectral, spatial, photometric, melanopic, and thermal performance of dosimeters Rugved Santosh Kore, Vincent Boyer, David Reichenberger, J Mundinger, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7160856/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 11 You are reading this latest preprint version Abstract Light is one of the primary stimuli for the entrainment of human circadian rhythms and holds enormous potential in aiding precision medicine. Past laboratory studies conducted in controlled environments highlighted the importance of photic history, intensity, spectrum, and timing of light exposure. More recently, field studies have indicated that analyzing the real-world impact of lighting on human health can be complex due to confounding factors. When properly designed, field studies can provide insight into occupants’ daily light exposure and be linked to physiological and psychological outcomes. However, measuring daily light exposure requires an accurate, durable, and affordable wearable light dosimeter that can be attached to a participant. Here, the spectral, spatial, and thermal performance of three wearable dosimeters (LYS Buttons, Blue Iris Specks, and Actiwatch Spectrums) are investigated. Light measurements taken by dosimeters under various lighting conditions, along with melanopic and photometric calculations, were benchmarked against a calibrated spectroradiometer. The LYS Button was the easiest to use and operate, albeit with reduced photometric accuracy. The Blue Iris Speck had the highest photometric and data-logging accuracy. The Actiwatch had the poorest photometric performance, which raises caution for scientific use. Results can help product designers and engineers improve their products and help chronobiology and sleep researchers to develop experimental protocols to account for weaknesses and capitalize on the strength of dosimeters. Future studies should evaluate the updated versions of the available light dosimeters and compare the performance of the dosimeters based on the wearing position on the user body. Physical sciences/Engineering Health sciences/Health care Physical sciences/Optics and photonics Dosimeter wearable devices circadian rhythms sleep health light exposure blue light Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 07 Oct, 2025 Reviews received at journal 25 Sep, 2025 Reviews received at journal 25 Jul, 2025 Reviews received at journal 24 Jul, 2025 Reviewers agreed at journal 24 Jul, 2025 Reviewers agreed at journal 24 Jul, 2025 Reviewers agreed at journal 24 Jul, 2025 Reviewers invited by journal 23 Jul, 2025 Editor assigned by journal 22 Jul, 2025 Submission checks completed at journal 22 Jul, 2025 First submitted to journal 18 Jul, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7160856","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":490425172,"identity":"78e28a8e-b9e4-4f99-881b-ea9f92c1a07a","order_by":0,"name":"Rugved Santosh 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