Preprints
Physiologically-relevant light exposure and light behaviour in Switzerland and Malaysia
Light plays a crucial role in syncing our internal clocks with the natural day-night cycle—vital for health and disease prevention. A new study compared real-world light exposure and behavior in Switzerland and Malaysia, revealing striking cultural and geographic differences.
How to deal with darkness: Modelling and visualization of zero-inflated personal light exposure data on a logarithmic scale
Handling zero-lux values in personal light exposure data is a major challenge in circadian and myopia research—especially when using common logarithmic methods. This study explores how to better visualize and model these tricky datasets using symlog scales and the Tweedie distribution.
Collecting, detecting and handling non-wear intervals in longitudinal light exposure data
In wearable light studies, participants often remove devices, creating data gaps that can skew results. This study tested multiple ways to detect those non-wear periods—like button presses, app logs, and light/activity sensors—and compared their accuracy.
Research articles
LightLogR: Reproducible analysis of personal light exposure data
Studying personal light exposure in real-world settings is key to understanding its impact on health—but messy, complex data from wearable devices makes this tricky. Enter LightLogR: a new open-source R package designed to simplify importing, analyzing, and visualizing light exposure data. With built-in metrics and tools tailored to real-life research, it helps bring clarity to a challenging field. Curious how LightLogR can streamline your light data workflow?
Metadata recommendations for light logging and dosimetry datasets
This peer-reviewed article provides guidelines on core metadata for light logging and dosimetry, promoting consistency, comparability, and enhanced quality in global research efforts.
Power analysis for personal light exposure measurements and interventions
Determining the right sample size in wearable light exposure studies is tough—especially with complex, real-world data. This study introduces a new method using hierarchical bootstrapping to estimate statistical power and sample size, tailored to different light metrics and study goals.
Protocol for a prospective, multicentre, cross-sectional cohort study to assess personal light exposure
Light affects everything from sleep to cognition, but most research has taken place in tightly controlled labs. This new international study introduces a protocol combining smartphone sleepiness ratings and multi-site wearable light sensors to capture real-world light exposure across diverse cultures and environments. By exploring how daily habits and surroundings shape our light intake, the study aims to inform future public health strategies. Want to see how culture and climate impact your daily dose of light?
Verification, analytical validation and clinical validation (V3) of wearable dosimeters and light loggers
Light isn’t just for vision—it shapes sleep, mood, alertness, and overall health, and can even be used as therapy. With new wearable light sensors (digital dosimeters) on the rise, there's an urgent need for clear standards to ensure their accuracy and usefulness. This article presents a robust validation framework to guide the development and evaluation of these tools in both research and clinical settings. Curious how wearables are changing the future of light-based health interventions?
What is the 'spectral diet' of humans?
Light shapes how we see the world—but it also deeply influences our biology, from hormone release to alertness and circadian rhythms. In everyday life, our light exposure is a complex mix of natural and artificial sources, constantly changing with our environment. This paper introduces the idea of a "spectral diet"—a new way to understand how the quality and composition of light in our daily lives impacts both visual and non-visual functions. Want to explore how light truly feeds the body and brain?
Software
LightLogR
A comprehensive tool for analyzing visual light exposure data, LightLogR is an open-source tool and detailed documentation to support reproducible and robust analyses of light exposure datasets, accepting many different file formats.
luox
luox is an open-source web-based platform for calculating α-opic quantities from spectral data. It is validated by the International Commission on Illumination (CIE).
Related projects & initiatives
Research Data Alliance - Optical Radiation Exposure and Visual Experience Working Group
This group focuses on creating metadata standards critical for harmonizing optical radiation exposure data. Adopting shared metadata standards significantly improves data accessibility, comparability, and research collaboration.
CIE JTC 20 (D6/D2) Wearable alpha-opic dosimetry and light logging methods, limitations, device calibration and data schemes:
The CIE Joint Technical Committee 20 (D2/D6) focuses on setting standards for wearable light loggers.
MeLiDos – Metrology for wearable light loggers and optical radiation dosimeters:
The MeLiDos project works on making wearable light loggers and dosimeters fit for use.
Project VEET
This initiative led by Reality Labs Research explores visual experience and environmental tracking, aiming to enhance our understanding of how everyday visual environments impact health and behavior through innovative research methodologies.