Uniformity of lighting for pedestrians is often assumed to have been achieved in mixed traffic environments when the lighting uniformity requirements for vehicular traffic have been fulfilled. Uniformity of lighting for drivers is commonly evaluated based on quantitative data on parameters such as overall luminance uniformity. However, methods for evaluating uniformity from the perspective of other road users are currently somewhat lacking. This study discusses qualitative and quantitative methods of assessing street lighting uniformity, and the potential implications for lighting design and the road users. We used convergence design and imbedded design based on two field studies. The research purpose is twofold: first, to study if, and how, measured lighting uniformity corresponds with visual perception. Secondly, to identify and explain the additional value that a combined method approach can contribute. The study considers examples of when the measured uniformity corresponds to visually perceived uniformity and when they do not correspond.

Previous research showed that light distribution can affect the perception of spatial size and shape. However, most studies are limited to quantitative assessment of a few scenarios without explaining possible causes behind peoples’ experiences. This exploratory study aimed to reveal complex relationships between light patterns and perceived size, and to investigate how light patterns affect perceived spaciousness. A qualitative approach was used with pair-wise comparisons between systematic visual observations of scale models. The observations confirmed that illuminated walls increase spaciousness. Yet, darkness impacts the perception of spaciousness as well. Both compound and separated light zones can expand depth, height, or width, depending on the interpretation of these patterns of light seen in relation to the whole spatial context. Furthermore, the position of illuminated areas, with placements on edge or in the center, may additionally influence perceived size.

Spaces can be perceived as larger or smaller, according to how lighting affects the spatial boundaries. This is knowledge that can be used for changing the appearance of a desolate square or a cramped space. The following is a full-scale study of changing light scenarios that was conducted with 222 respondents in an urban space over five weeks. The study examines the effect of the spatial distribution of light and the placement of luminaires on our spatial understanding. A mixed methodology strategy, which combines pair-wise comparisons with qualitative interviews and a questionnaire, was used to examine the respondents’ perception of differences in spatial size and shape. The findings show that illuminated surfaces and objects, such as facades and trees, create a perception of increased or decreased depth, height and distance, depending on the spatial context and the respondent’s pre-understanding. Additionally, the perceived size of space was found to follow the height of the luminaires’ placement. This research study raises awareness of the impact of the placement of luminaires at varied heights, by developing the concept of light topography.

Lighting uniformity is a key factor in traffic safety, and it could even result in energy savings for light installations. However, highly uniform horizontal road lighting for motorized vehicles may not be optimal for pedestrian roads. Therefore, it is important to evaluate the way in which pedestrians experience road lighting uniformity. Accordingly, we employed a qualitative approach to examine pedestrian road lighting uniformity. Visual analyses were used to exemplify and discuss the perceived uniformity. The case studies were performed on three pedestrian roads with similar light installations. The results show that the experience of road lighting uniformity differs substantially between the three roads. Based on the case studies, there are many aspects that need to be considered beyond the light falling on the horizontal surfaces. This study suggests that the visual experience of road lighting uniformity for pedestrians is difficult to estimate with photometric values because the visual impact of uniformity is highly influenced by the spatial context and landscape.

The lighting design education was recently converted to a three-year bachelor program, from a two-year non-engineering track, in which students' group design exercises resembled a design studio process characterized by high uncertainty, self-anchored problem solving and creativity. Consequently, students who attends to this program is less disciplined in engineering which predominates other educational programs at the School of Engineering. The aim of this study was to map the Lighting design students' ability for a problem-solving approach and their ability of control in group design exercises to create a strategy for sustainable change, if necessary. The study employed a mix-method approach. In the quantitative data gathering, an online survey collected 18 students' responses using convenience sampling on locus of control. Additionally, this survey registered the student's perception on the experienced group design exercise in terms of how concrete (assignment-based) or open (problem-based) the design exercise was. The visualization of this data together with the locus of control measurement revealed that students in the first year (N=4) tend to be located centrally with no preference for problem solving approach. In the meantime, the second-year students (N=6) developed an open (problem-based) approach to problem solving, while their overall control in life is still more external. Finally, the trend for the students on the third year (N=8) move to a more assignment-based approach and more to an internal locus of control. The qualitative investigation involved three focus group interviews (N=13) emphasizing on the following themes: open/closed projects, control, the teacher's role, instructions, demands, realism in the projects, project size, project budget, project time, group dynamics, group size, group roles, leadership, personality, and conflicts. Results reflect a shift in confidence in the ability to exert control over one's own motivation and behavior in the group design exercise. The themes were also reflected in the content of the focus group interviews. Based on these findings and according to the adaptation and implementation of a CDIO's design-implemented experiences, the preparation for introducing small gains for students and staff members were proposed.

This study explore how distribution of light impacts perceived space. The purpose of this study was to gain a rich and deep understanding of the relationships that exist between distribution of light and spatial experience. In this research, spatial complexity is studied through a qualitative approach with a combined methods strategy. 21 informants answered a questionnaire and drew sketches, followed by in-depth interviews in a real-life auditorium with five light scenarios. The scenarios varied in light distribution, light level and light colour. All findings were triangulated in the final analysis. Surprisingly, a dark room appeared as more spacious when the spatial boundaries become unclearly defined. Simultaneously, findings indicate that bright walls can, in contrast to what most previous research suggests, contribute to a decreased spaciousness, if they become prominent enough. The results indicate a relationship between perception of increased width, caused by wall lighting, and reduced height, caused by indirect ceiling light. The experience of room size and spatial enclosure in relation to light distribution did not follow physical room boundaries. Furthermore, interview answers indicate that there can be a relationship between lighting and social interaction.

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Hur påverkar belysningen hur vi ser och upplever rum? Att uppfatta rum visuellt är inte alls samma sak som att utgå från det fysiskt mätbara rummet. Är det ljus eller mörker som gör att en yta uppfattas ligga längre bort? Kan ljuset påverka den sociala dynamiken i ett rum? Hur kan man öka trygghetskänslan på en plats? Kan ett rum uppfattas som mer eller mindre rumsligt? Den här boken ger svar och stimulerar till nya frågor.

I boken varvas teori om perception, ljus och rum med praktiska tips om analysmetoder och skissteknik. Den ger grundkunskap i arkitektonisk ljusdesign men presenterar inga färdiga lösningar. Den uppgiften – att skapa ljusmiljöerna – är din!

The relationship between distribution of light and spatial experience was studied using a temporary lighting installation in a real-life urban environment. A questionnaire, interviews and focus discussions collected the experiences of the illuminated space from 222 people. The following assumptions were confirmed: a clearly defined space created by illuminating walls and trees and visual limits contributed to a feeling of safety in the space because these limits helped establish an overall view of this space. A lower luminaire placement in the street contributed more to a feeling of safety than a higher luminaire placement because the light was closer to the person, highlighted the facades and made the space appear lower. The light topography, e.g., the luminaire height, is discussed in relation to power and spatial hierarchies. 

This paper contributes to existing research by showing the influence of the distribution of light on the perception of a space. It addresses the importance of conceptual awareness and the impact of informants' possible pre-understandings. It combines and develops research methods that can accommodate the complexity of real spaces through patterns and relationships. Additionally, it includes concept development of spatial understanding. This primarily qualitative approach of dealing with complex spaces provides a new and unique contribution to the field of lighting research. This lighting design research consists of experimental studies within three different complex spatial contexts, from scale models to interior and exterior spaces. The importance of visual spatial boundaries and brightness patterns are discussed in relation to enclosure, perceived dimensions and atmosphere. It is more cost effective to make a space more spacious by changing the distribution of light than by changing the physical space through alterations. Light may generally have an enlarging effect, though sometimes it can have the opposite effect. This paper addresses how the placement of luminaires, the direction of light and the focus and spread of the light impact the perceived spatial dimensions and experience of atmosphere. A light zone can include as well as exclude participants. A focused light may call for attention, causing an audience to lower its speaking volume. Distribution of light is also useful for dividing a large office landscape into spatial units. The light topography—the upper boundary created by the heights of luminaires in a space—and light direction are factors of empowerment. A clearly defined, tangible space seems to also contribute to an experience of safety. Illuminated vertical surfaces can contribute to a clear overview and a clearly defined space that is experienced as having a sheltering and embracing effect.