What is good lighting when the vision changes?

Lighting impacts how we feel – if we feel secure or vulnerable, awake, or sleepy. You know the feeling in a club or some other dimly lit space, when someone suddenly turns the bright lights on, and the magical atmosphere disappears. 

Or how the first sunny days in spring after the long cold winter months fill the air with joy and promise of happy events.

In a new research project at Aalborg University in Copenhagen, we study the role of lighting when the vision changes in older age.

Our starting point is to study the meaning of light as a whole: Not only regarding visual abilities, but the other senses and the social aspect too.

There is a lot of research regarding what kind of lighting generally helps elderly people to perform visual tasks most quickly and effectively. 

However, the same research articles and our initial findings also show that individual variations are great, and generalisations do not hold in many cases. Therefore, it is important to assess needs and hopes for lighting individually.

How are we doing this? Primarily via interviews with the people who are directly affected. 

Not just one light preference

In the years 2023-24, we are aiming to interview 40 participants older than 55 years old. As a PhD student, I also have a special focus on studying and developing methods to describe and register lighting conditions in the homes. 

As we already know that individual variations in preference will be great, we are not expecting to find simple answers about what is good or bad lighting. 

We are more hoping to map the scope of variations in lighting preferences and to find ways to embrace these differences in lighting design.

This is in line with the principles in universal design research, where it is acknowledged that people are different, have different needs, and there is a need for diversity in design solutions.

The way we see changes with age

Lighting design for elderly often has focused on how lighting can enhance their ability to see more clearly. 

The structure of the ageing eye changes so that less light reaches the retina, making especially dimly lit situations seem even darker. 

Young people might be able to read printed text in candlelight, while older people are probably inclined to search for stronger light sources when reading. 

Another common change in the ageing eye is scattering of light inside the eye, resulting in a more foggy view of the world. 

Changes in the composition of the field of view are also common: Some people start to experience a more narrow field of view, and some get blind spots.

You may have perfect vision today, but at some point these changes will also happen to your vision. 

Helping older people to see better is a good and important cause. 

But often something gets lost in this narrative, which is that lighting also affects how we experience spaces (i.e. this space feels very bright and airy) and ourselves in the space (I feel light in this room). 

The values in universal design research also stress that lighting design should not only support visual tasks, but also the experience of being in a space and possibilities to take part in common activities and to interact equally with others.

Previous research on the home lighting preferences of the general population in Denmark show, that people often turn on lighting more for atmospheric reasons than visibility.

Light impacts human experience

Different people might prefer different lighting, even if they share the same diagnosis. Our personalities, beliefs and cultural backgrounds affect, how we evaluate our surroundings.

As an example of how previous experiences and beliefs can affect lighting preference, we have noticed while visiting our participants, that many of them choose to keep most of their lamps turned off in everyday situations. 

Some people say that they prefer it dark because it is cozier. Another very common argument is that it’s saves energy. 

They tend to talk about the energy saving aspect with pride and joy – they feel happy that they are saving money and being climate friendly. 

As light researchers, we could argue that it would be more beneficial for them to use more lights, so it would be easier for them to navigate, find objects and prevent falls. 

Especially today, when the LED light sources do not use that much energy, compared to the incandescent lights in the old days. 

But is encouraging increasing the light levels worth it, if it lessens the feelings of ‘hygge’ (cosiness) and joy of energy saving, and maybe even their feeling of ‘authorship’ of their homes? 

In this way, the question of home lighting is not only visual and technical (as many light designers seem to treat it when designing for the elderly) but contains psychological and philosophical aspects too.

Different approaches to lighting

In the context of universal design, we could explain these points of views as medical or social understandings of disability. 

If our understanding of visual impairment is purely medical, then we will do our best to prevent the effects of vision loss clinically: by using medicine and assistive devices, such as eyeglasses, canes and/or special lighting. 

But if we add a social understanding of disability, then we will include questions such as: 

How does each individual experience their vision loss? How do they experience lighting? What kind of support do they wish for? 

And we will be aware that a ‘diversity in needs requires a diversity in solutions’.

In the universal design research group, we believe that by combining medical and social understandings of vision loss and lighting, we can support better lives and create better living environments.

Because ultimately, applying a universal design approach calls for an inclusive and interdisciplinary perspective and understanding of the human body.

Older people are not patients who needs light to be ‘rescued’. They are first and foremost individuals with emotions, hopes and needs. 

They deserve their lighting to be both functional and cosy. Luckily for them, research indicates that that’s very much possible. 

This article is the result of a cooperation between Videnskab.dk and Bevica Fondens Universal Design Hub.