Light is not only responsible for vision, but it is also capable of affecting mood, performance and the circadian system in our body, a complex network of interconnected organs that controls many important biological processes. Thanks to the sunlight that comes to our eyes, physiological functions such as sleep and wakefulness, body temperature, heart rate, genetic transduction, hormonal secretions, alertness, performance and memory are regulated according to the circadian rhythms which recur around every 24 hours. Proper regulation of the circadian system is therefore very important for our health and well-being, and adequate exposure to natural light during the morning is the most effective way to achieve this goal.

Because people spend most of their day in confined spaces, they may not get enough exposure to natural light to ensure the synchronization of the biological clock or, conversely, they may get excessive exposure stimulation from unsuitable, artificial light in the dark hours of the day. This can result in effects on health; from sleep disturbances to the onset of more serious illnesses. Hence the importance of a correct supply of artificial light, of appropriate intensity and spectral characteristics.

Human Centric Lighting (HCL), lighting for the individual, was born with the objective of staisfying visual requirements (comfort and performance) and non-visual (circadian effects, productivity and mood) while being energy efficient. Exposure to proper lighting can enhance concentration, safety and efficiency at home, at work and in learning environments. It can also support healing processes and prevent chronic illnesses in the elderly, and contribute to the prevention or treatment of pathologies such as Seasonal Affective Disorder (SAD), or winter depression, Alzheimer’s, dementia, and sleep disturbances.