In the modern society, the majority of people spend about 90 percent of their time indoor, leading to the issue of lacking explosion to natural sunlight. This further causes disruption of people’s circadian system, which connects to sleep disorder and depressed moods that would negatively affect productivity for work and study.

In order to solve the problem, human centric lighting (HCL) applications have attracted more attention. HCL mimics natural light with adjusted colors that shift from bright blue-rich white during the day time to keep people alert and focus to relaxing red and orange hues at night enhance the body's natural response to sunset. By following the natural circadian rhythm, HCL helps to improve well-being of people.

(Image: Osram)

A study carried by the Lighting Research Center has have disclosed that people who receive circadian-effective light experienced better sleep and lower levels of depression and stress. Another study pointed out that people exposed to circadian-effective light at work feel more energetic and vital.

However, lighting environment in work places might not fulfill the needs of most people. A survey by Repro-Light, a research project aiming to build a sustainable lighting industry in the EU, found out that European workers are looking for improved lighting at work places. The survey engaged with 1100 workers across Germany, Spain, Italy and Austria and noted that 56 percent of the participants said they would like better work place lighting. In addition, over 90 percent of those questioned said work lighting has impact on their mood while 87 percent believes it affects their performance.

These researches revealed how lighting affects people’s emotion and productivity and underlined the significance of work place lighting. Leading lighting companies including Signify and Osram have been promoting connecting lighting system in buildings and offices to lead the trend. LED makers like Nichia, Seoul Semiconductor and other companies also launched various tunable LED products for HCL applications.