Public defence: Helga Iselin Wåseth - Universitetet i Sørøst-Norge

Helga Iselin Wåseth will defend her PhD degree in Person, Health and Society. This PhD investigates how footpath lighting can be designed and assessed using a three-dimensional light-field framework to balance pedestrians’ perceived social security with reduced ecological impact from artificial light at night.

15 Sep

Practical information

Date: 15 September 2026
10.00 - 15.00
Drammen, Auditorium A5508 and Zoom
Download calendar file

Link to digital participation (Zoom)
Meeting ID: 646 5148 3453
Password: 150926

Program

10.00. Trial lecture: TBA

12.30. Public defence: Capturing social and eco-centric light fields

Evaluation comittee

First opponent: Associate Professor Frédéric Leloup, KU Leuven, Belgium
Second opponent: Professor Maria Elisabeth Johansson, Lund University, Sweden
Administrator: Associate Professor Arnulf Myklebust, University of South-Eastern Norway
Chair of the Defence: Professor Mirjam Lukasse, University of South-Eastern Norway

Supervisors

Principal supervisor: Professor Sylvia Cornelia Pont, Delft University of Technology, the Netherlands
Co-supervisor: Associate Professor Veronika Zaikina, University of South-Eastern Norway

Any questions?

Aline Craide
35 02 65 15

Helga Iselin Wåseth is defending her thesis for the degree philosophiae doctor (PhD) at the University of South-Eastern Norway.

Portrett av Helga Iselin Wåseth She has pursued the PhD program in Person, Health and Society at the Faculty of Health and Social Sciences, Department of Optometry, Radiography and Lighting Design.

You are invited to follow the trial lecture and the public defence.

Link to the dissertation will come here

Summary

A PhD study by Helga Iselin Wåseth at the University of South-Eastern Norway shows that managing light distribution plays a crucial role in maintaining, or even improving, pedestrians’ sense of safety after dark, and may be a part of a tool for reducing light pollution.

The results showed that the light distribution over the face was more important than surface light levels for pedestrian reassurance. A lower-intensity luminaire provided equal or improved assessment of cues for safety compared to a conventional, brighter solution. The alternative design also reduced stray light spilling into surrounding areas, which can disturb wildlife and ecosystems. Snow and cloud cover were also found to significantly increase light spread, highlighting the potential in adaptive lighting strategies for reducing light pollution.

The research suggests that by introducing the light field framework in outdoor lighting design, the lighting designer is provided with tools to assess the lighting quality, both at the footpath and its implications for sense of safety and as a tool to assess the stray light into surroundings. This approach can shift the focus from quantity to quality in the lighting design calculation practice, while still having quantitative performance metrics. By shifting the focus from quantity to quality, the effects can be that we sustain a sense of safety on lower light levels, with the added benefits for nature and wildlife.

Artificial light at night is increasing worldwide and is known to disturb wildlife and reduce the view of a natural starry night, while it also provides visibility and a sense of safety on our evening walks and is an important part of urban infrastructure. This research demonstrates that managing the light distribution may be a tool to balance these opposing needs.

The study examined how lighting on footpaths affects how approaching pedestrians are perceived, but also how the surrounding environment is affected. The research looked at how light spreads in the three-dimensional field around a person’s face and into the surrounding terrain.