Harmonizing Light Dosimetry: Illuminating a Unified Path
Henrik Clausen is Director of the Fagerhult Lighting Academy, as well as Associate Professor at Aalborg University in Copenhagen. He is tasked with keeping Fagerhult’s general lighting knowledge up to date, and that includes reading many scientific papers.
Sharing his thoughts on papers he finds especially interesting and/or thought-provoking is one of the aspects of this role he loves.
Recently, Henrik posed the question - ‘Can we dose the right amount of light?’
To a certain degree, we can. But, there is an underlying concern about light dosimetry, and here, Henrik would love to give you a little more to think about...
In the vast canvas of scientific exploration, the study of light's effects is like an artist's palette of endless colours. Just as different artists apply unique brushstrokes to create their masterpieces, researchers approach light dosimetry with their own methods and metrics.
These variations, while showcasing the diversity of scientific exploration, also raise a challenge — a challenge to compare and align different works of art or in this case scientific results, for a clearer, unified understanding.
Consider this: scientists from various corners of the world, armed with their tools and knowledge, delve into the realm of light dosimetry. They strive to capture the intricacies of light's influence on our well-being, just like artists capture the essence of light in their paintings. And, just as each artist's style brings forth a different story, each scientist's approach to dosimetry has the potential to yield unique insights.
These diverse approaches are like different colours on the canvas, representing the nuances of light's impact. But, imagine trying to create a cohesive artwork by blending those colours without a shared understanding of their shades and tones.
Similarly, without a common framework for measuring and quantifying light's visual, emotional, and biological effects, scientists find themselves facing a complex puzzle - how to compare their findings in a meaningful, standardised and comparable way?
It's as if a symphony is being played, with each musician interpreting the notes in their own, slightly different way. Yet, to create harmony, the musicians must follow a conductor's guidance and stay in tune with each other. Similarly, the field of light dosimetry needs a conductor - a common frame of reference that guides scientists in choosing the right "notes" (metrics and procedures) to measure light's impact consistently across studies conducted on different locations in time and space.
Imagine a world where different dosimetry studies are like puzzle pieces that fit together seamlessly. By aligning their metrics, scientists can create a clearer picture of how light affects us. This alignment doesn't have to be stifling creativity; rather, it's about providing a shared language that allows scientists to communicate their findings, methods and procedures effectively to their peers, for them to understand, compare and reproduce these findings, fostering a deeper mutual understanding and thereby the very understanding of light's biological and non-visual role in all our lives.
In this quest for alignment, researchers aim to bridge the gap between various brushstrokes of scientific exploration. By using common metrics and methods, they can enhance the comparability of their work. This, in turn, leads to a broader perspective on the effects of light, helping us understand the dosage of light we need for optimal health and well-being.
Just as artists contribute to a collective understanding of the world through their creations, scientists too, contribute to our understanding of light's impact through their studies. By harmonising their efforts, they create a symphony of knowledge that benefits us all.
So, as the world of light dosimetry continues to evolve, scientists work towards aligning their brushstrokes of discovery, painting a clearer, more harmonious picture of the profound effects of light on our lives.
Light and people
Light has always been a prerequisite for human existence. Inspired by daylight and the latest science, we can create lighting that makes life even better. Humans are made to be outdoors, and daylight affects the way we are – biologically and psychologically. New research has shed light on these links.
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Flick notes that the most successful projects involve user engagement and early collaboration across disciplines, with designers sharing decisions on finishes, daylighting and spatial layout to create coherent, comfortable spaces. Ultimately, designing with empathy – listening to students, empowering teachers and applying evidence-based guidance – ensures that every educational setting becomes a place where all learners can thrive. If you’re working on a project and want to discuss how lighting could make it more inclusive, please get in touch. Co-Authors Flick Ansell – Associate Director, Lighting. AECOM Dr Jemima Unwin Teji (UCL) Lecturer in Light and Lighting Research input from Beatrice Chui Ling Yuen – MSc in Light & Lighting 2022 - Assessing illuminance preferences in Neurodivergent Individuals Ruoxi Yin PhD 2026 - Modulating Emotional Perception Through Colour in Neurodivergent Individuals Tommy Smith MSc 2025 - Investigating the impact of lighting on user comfort and cognitive ability amongst neurodivergent individuals: A case study of a SEN school in London. [1] Beatrice Chui Ling Yuen – MSc Light & Lighting Dissertation 2022 - Assessing illuminance preferences in Neurodivergent Individuals. Supervised by Dr Jemima Unwin Teji. [2] Ruoxi Yin PhD Student 2026 - Modulating Emotional Perception Through Colour in Neurodivergent Individuals paper presented at IEEE Sustainable Smart Lighting World Conference 2025, Monastir, Tunisia, December 2025 [3] Tommy Smith MSc Student 2025 - Investigating the impact of lighting on user comfort and cognitive ability amongst neurodivergent individuals: A case study of a SEN school in London.