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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While full circadian lighting strategies can be difficult to implement across the sales floor, where lighting is often driven by brand standards and visual merchandising requirements, they can be far more effective in staff-focused areas such as break rooms, back-of-house spaces, and cafés. In these environments, lighting can be tuned to support how the space is used throughout the day. Brighter, cooler light may help support alertness in staff areas during early or busy shifts, while warmer, softer light can help create a calmer atmosphere in break spaces later in the day. In customer dwell spaces such as cafés, dynamic lighting can also help shape the pace and feel of the environment, creating brighter, more energised settings during peak periods and warmer, more relaxed conditions later in the day. For staff spending extended time in these environments, this more considered approach to lighting can help create spaces that feel more comfortable, functional, and supportive across the working day. 2. Design for the Task, Not Just the Space Retail staff move constantly between tasks, from replenishing stock and changing displays to operating tills and helping customers. Each task places different demands on the eye, which means lighting needs to support the activity as well as the environment. In practice, this means pairing consistent ambient lighting with more focused task lighting where detailed work takes place, such as stockrooms, fitting rooms, service desks, and checkout areas. Much of this should already be addressed through good lighting design practice. Appropriate light levels, glare control, and visual balance are fundamental to creating spaces that are safe, comfortable, and functional for staff. 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Even small changes to lighting can make a noticeable difference to staff wellbeing and the day-to-day running of a store. To learn more about designing retail environments that support wellbeing and inclusivity, contact Fagerhult today. A few carefully considered lighting interventions can change how your team feels, works, and connects, creating happier staff and more satisfied customers.
Why Uniform Lighting isn’t Enough for Modern Workplaces
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Inclusive lighting is not about finding a single ideal setting but about creating adaptable environments that support diverse needs throughout the day. Local dimming, zoned lighting, personal control and lower-stimulation areas can all help make workplaces more comfortable. Inclusion depends less on uniformity and more on flexibility. From Static Illumination to Dynamic Lighting Standard office lighting has traditionally focused on delivering a maintained average light level across a workspace. While this supports visibility, it does not fully reflect how people respond to light throughout the day. Human physiology is closely linked to daylight, which shifts in intensity and colour over time. Research suggests that changing light conditions may better support alertness, concentration and cognitive performance than constant lighting. “Static lighting assumes people need the same thing all day. In reality, effective workplace lighting has to respond to changing visual, biological and emotional needs.” — Leslie Thomas, Lighting Technology Manager, Fagerhult UK This is where Human Centric Lighting and Double Dynamic Lighting become relevant. Rather than treating light as a fixed background condition, these approaches consider its visual, biological, and emotional effects, balancing comfort, performance, mood, and well-being. A More Responsive Approach If uniform lighting no longer reflects how modern workplaces function, the alternative is not simply more light, but smarter use of it. A more responsive approach combines ambient, task and accent lighting to create greater visual hierarchy and flexibility. Subtle shifts in tone, intensity and contrast can help define spaces for focus, collaboration and restoration without physical separation. Responsiveness also depends on control. Zoned lighting, local dimming and personal adjustment allow users to shape their immediate environment, while connected systems can respond in real time through occupancy sensing, daylight integration and automated dimming. This improves comfort, supports more efficient use of space and ensures light is delivered where and when it is needed. Lighting as Part of Workplace Performance Workplace lighting should no longer be treated as a background utility designed purely to meet technical requirements. It plays a direct role in how people feel, how well they focus and how effectively they work throughout the day. Light influences more than visibility. It shapes concentration, comfort, mood and alertness, affecting both individual performance and the overall experience of a space. When designed to support comfort, adaptability and human rhythms, lighting becomes a strategic workplace tool rather than a compliance exercise. Rethink What Workplace Lighting Should Deliver If your workplace lighting strategy still prioritises uniformity above all else, it may already be limiting comfort, flexibility and performance. Speak to us to discover how our adaptive lighting solutions can create more responsive, inclusive and effective workplace environments.