Lighting the Future
by Marina Kondakova
Lighting is an essential part of our lives. As solid-state lighting (SSL) technology advances, we expect that luminaires will become more than just illumination sources. Numerous research studies suggest that the lighting in our environment affects our productivity and alertness, and can influence our physical health and well-being. Lighting affects performance and safety in industrial spaces. A recent study showed that improving the quality of light can help reduce risk in primary causes of occupational injuries.1 The role of lighting is also increasing in the emerging areas of “smart” buildings and vehicles. Increased connectivity makes it possible to automate, monitor, and control all operational aspects of commercial buildings, for example. Lighting fixtures can include smart sensors and controls for the network for collecting data throughout the building.2
Presently, one of the most widely discussed topics of the effect of lighting on humans is circadian wellness. Our circadian rhythm is synchronized with the 24-hour cycle and triggered by natural periods of light and dark. The article by Dr. M. Figueiro, Director of Light and Health Programs at the Lighting Research Center (LRC), discusses differences in the way that light affects the circadian and visual systems. Because the circadian system responds to multiple factors, such as timing, duration, and amount of light exposure as well as spectral properties of the light, the design of circadian-healthy lighting requires different rules.3 The LRC recommends use of the circadian light (CLA) and circadian stimulus (CS) metrics that characterize impact of light on human circadian systems to help designers create healthy lighting.
Dr. Figueiro presents the results of multiple studies on the effects of light exposure from self-luminous displays on melatonin suppression. Melatonin is a hormone produced by the human body that helps control the sleep-wake cycle.4 Disturbance of the cycle has detrimental effects on health. The studies conducted showed that exposure to short-wavelength blue light from device screens at night resulted in decrease of melatonin levels, especially in adolescent participants. However, properly controlled exposure to blue light during the daytime can increase alertness. Such exposure was used to improve the sleep and behavior of Alzheimer’s patients. Thus, the results presented in this paper contribute to our understanding of light’s impact on our well-being, and show that the new use of modern lighting can provide very significant benefits.
Rapid development of LED and, particularly organic LED (OLED) lighting technology has allowed for dramatic changes in form, scale, and application of luminaires. While a wide variety of commercial LED products have been available for a while, OLED lighting is just starting to enter the lighting market.
OLED offers a new perception of light; it provides pleasant, diffused illumination from a large surface rather than from a point source. The light is soft, casting no shadows or glare. Its quality is similar to natural sunlight. OLED panels enable new, creative lighting designs because they are extremely thin, lightweight, and capable of operating at temperatures near ambient. The panels can be made on flexible or rigid substrates.
In the article, “OLED Lighting Hits the Market,” OLEDWorks’ Business Development Director G. Phelan discusses various applications for OLED lighting and provides an overview of commercially available products. The author points out that OLED’s unique form factors, such as thinness, lightness, and flexibility, will be key differentiators from LED lighting systems. OLED lighting products are currently higher priced than those based on LEDs. However, as their performance is continually improving and costs are decreasing, OLED has become a viable component of lighting technology.
The articles featured in this issue describe the latest trends in development of lighting technology. The role of lighting is changing as we continue learning about its additional functionalities, including its effects on people and the environment.
References
1A. Jayawardena, D. Duffy, J. M. Manahan, “Lighting Matters in Industrial Environments: A Framework Linking Workplace Safety to Lighting Quality Metrics,” IEEE Industry Applications Magazine, 23(3), 2017.
2E. Petridis, “Standardizing IoT for a Brighter Future in Commercial Buildings,” CE Tech Trends, 2017. http://enewsletters.construction exec.com/techtrends/2017/10/standardizing-iot-for-a-brighter-future-in-commercial-buildings/
3M. G. Figueiro, K. Gonzales, D. Pedler, “Designing with Circadian Stimulus,” LD+A, 2016, p. 30–34.
4https://sleep.org/articles/melatonin/