This article describes the development of a device to investigate the non-visual responses to light: The Light-Dosimeter (lido). Its multidisciplinary team followed a user-centred approach throughout the project, that is, their design decisions focused on researchers’ and participants’ needs. Together with custom-made mountings and the software Lido Studio, the lidos provide researchers with a holistic solution to record participants’ light exposure in the near-corneal plane in laboratory settings and under real-world conditions. Validation measurements with commercial equipment were deemed satisfying, as was the combining with data from other devices. The handling of the lidos and mountings and the use of the software Lido Studio during the trial period by various researchers and participants were successful. Despite some limitations, the lidos can help advance research on the non-visual responses to light over the coming years.
Research on the non-visual responses to light under real-world conditions has been hindered by the lack of suitable measuring devices. Here, we present a novel, portable and miniaturised light-dosimeter attached to a spectacle frame, taking measurements in the near-corneal plane. The recorded data is processed with the help of the custom-made software package Lido Studio. In addition to commonly used metrics such as illuminance and correlated colour temperature (CCT), it also provides metrics standardised in CIE S 026:2018. Data can be analysed directly in Lido Studio or exported as a PDF report or a comma-separated values (CSV) file for further in-depth time-series analyses. The Federal Institute of Metrology (METAS) optics laboratory (Bern-Wabern, Switzerland) assessed the light-dosimeter’s spectral and geometric properties. Subsequentially, the team at the Centre for Chronobiology (Basel, Switzerland) confirmed that measurements performed with a light-dosimeter were comparable to those from a commercial spectroradiometer.
Two studies investigated how lighting influences perception of various materials. Experiment 1 focused on preferences of cold or warm light. Participants' task was to indicate preference for either coolish or warmish light for 20 different materials. The selection included materials typically used for wall or floor of interior spaces. Different hues and surface characteristics were present. Specifically two materials of blue color (cold hue) were preferred in a cold light while red carpet (warm hue) and synthetic turf materials were preferred in warm light. This latter choice was explained by automatic reference of synthetic turf to the appearance of natural grass. There were no clear light source preferences for other materials. Experiment 2 explored how the same 20 materials are evaluated under LED lighting in comparison to three other lighting situations (halogen lamp, highintensity discharge lamp, and compact fluorescent lamp). The results of this explorative study were not conclusive. The materials chosen for this experiment differed greatly in their structure and optical properties. In conclusion, light influence on the evaluation of materials needs systematic investigation in future research.
Light therapy is applied as treatment for a variety of problems related to health and ageing, including dementia. Light therapy is administered via light boxes, light showers, and ambient bright light using ceiling-mounted luminaires. Long-term care facilities are currently installing dynamic lighting systems with the aim to improve the well-being of residents with dementia and to decrease behavioural symptoms. The aim of this chapter is to provide an overview of the application of ceiling-mounted dynamic lighting systems as a part of intelligent home automation systems found in healthcare facilities. Examples of such systems are provided and their implementation in practice is discussed. The available, though limited, knowledge has not yet been converted into widespread implementable lighting solutions, and the solutions available are often technologically unsophisticated and poorly evaluated from the perspective of end-users. New validated approaches to the design and application of ambient bright light are needed.
Exposure to light fundamentally influences human physiology and behaviour by synchronising our biological clock to the external light-dark cycle and controlling melatonin production. In addition to well-controlled laboratory studies, more naturalistic approaches to examining these "non-visual" effects of light have been developed in recent years. As naturalistic light exposure is quite unlike well-controlled stimulus conditions in the laboratory, it is critical to measure light exposure in a person-referenced way, the "spectral diet". To this end, light loggers have been developed to capture personalised light exposure. As an alternative to light sensors integrated into wrist-worn actimeters, pendants or brooch-based light loggers, a recently developed wearable light logger laterally attached to spectacle frames enables the measurement of biologically relevant quantities in the corneal plane. Here, we examine the usability and acceptability of using the light logger in an undergraduate student sample (n=18, mean+1SD: 20.1+1.7 yrs; 9 female; Oxford, UK) in real-world conditions during a 24-hour measurement period. We probed the acceptability of the light logger using rating questionnaires and open-ended questions. Our quantitative results show a modest acceptability of the light logger. A thematic analysis of the open-ended questions reveals that the form factor of the device, in particular, size, weight and stability, and reactions from other people to the wearer of the light logger, were commonly mentioned aspects. In sum, the results indicate the miniaturisation of light loggers and "invisible" integration into extant everyday objects as key areas for future technological development, facilitating the availability of light exposure data for developing personalised intervention strategies in both research, clinical and consumer contexts.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.