Rodriquez and teammates determined via a virtual-reality-based study that we prefer apparent daylighting levels to vary from time to time in viewed urban environments; their findings may be useful to people developing virtual spaces, for example. The group shares that their work “analyze[d] subjective reponses to lightness changes in outdoor views with respect to three view constructs (i.e., preference, recovery, and imageability). . .
Which light is best? Houser and colleagues report that “light is still for vision, and lighting for visibility, visual comfort and visual amenity is as important as ever. Complementing the old is new awareness and responsibility for how light and lighting influence non-visual responses in humans. Circadian, neuroendocrine and neurobehavioural responses are important for human health and should be considered on-par with visual responses. This awareness leads toward lighting design solutions with increased contrast between day and night.
Hvass and teammates investigated how lighting urban spaces influence perceptions of experiences there. They determined via a field study in public transportation waiting areas and a laboratory experiment (where one light zone simulated the same sort of waiting area and the other the surrounding urban space) that “participants perceived the atmosphere in the simulated waiting area as relaxed and private when luminance intensity was low.
Lighting the way to eating goals
Mahmoudzadeh and teammates add to the literature linking worker lighting control and workplace experiences. The group found that when “participants took part in a 3-phased experiment with immersive virtual environments (IVEs). . . . The results of the research revealed that an energy efficient interactive lighting system that gave the participants a perception of control satisfied the participants in terms of lighting the same as a conventional lighting system that gave them full control. . .
Theodorson and Scott researched lighting preferences. They report that their “research explores the human response to colored lighting with light emitting diodes (LEDs) in a space with the intent of understanding preference and affectual [emotional] response. The research was conducted through photographic appraisal of a single interior space illuminated with monochromatic and mixed colored lighting. Results indicate that. . . . When mixed color lighting is introduced, there are preferences for warm colors.”
Ozkul, Bilgili, and Koc studied how the color of light used in a restaurant influences diner experience. The researchers found when “five experiments were conducted in five ambient lighted in different colors. . . . the perception of service quality and the level of satisfaction were higher in red and yellow-lighted ambient than those in blue and green-lighted ambient.” Some technical details: “Yellow, blue, red, and green lights were obtained by covering the surface of white bulbs with colored gelatin. .
Tian, Chen, and Hu looked at appropriate levels of circadian stimulus (CS) by age. They determined that “the effect of the CS increased with CCT from 4000 K to 8000 K at the same age as a general trend; however, the CCT of 2700 K shows a higher circadian impact compared to that of 4000 K for the same age groups. . . . In order to provide sufficient CS, the minimum corneal illuminance for children and elderly is 250 lx and 380 lx, respectively, when the CCT of the light source was 2700 K.
Conditions and their consequences
The Lighting Research Center, Rensselaer, has released materials that can support the development of energy efficient circadian lighting n classrooms and hospitals. As a press release from the LRC reports the LRC team “published new guidance documents for designing circadian-effective lighting in K-12 classrooms and hospital patient rooms while avoiding increased energy use. . . .