Light direct affects our emotions and circadian rhythm. Light is electromagnetic radiation that is reflected by the surfaces of objects around us, which we perceive with our eyes. This is what lets us to see the world around us, including colour, which is nothing more than the ability of a material to reflect a certain colour of light. Throughout the day, we are exposed to different kinds of light, whether sunlight with different wavelengths depending on the angle it strikes the Earth, or artificial light, which has different qualities depending on its source.
In the early morning and evenings, sunlight has low colour temperatures and wavelengths. Low colour temperature stimulates the hormone melatonin in the body and helps us relax. During the day, however, sunlight has a high colour temperature and short wavelengths, which stimulates the hormone serotonin in the body and increases alertness. These differences support the proper functioning of our body’s circadian rhythm, which helps our body remember when to sleep and when to be awake.
As well as different colour temperatures, artificial lighting has a colour rendering index indicated on a scale of 0 to 100, which should be selected according to the time of day and activity performed under the lighting. For work in an office, school, laboratory or other workplace from around 8 am to 4 pm, lighting with a colour temperature of 4000–6500 K, which keeps us alert, is strongly recommended. At home, where we usually spend most of our time in the morning and evening, we should have a colour temperature of 3000–2700 K, which helps us relax. However, today we can also have lighting that changes its colour temperature.
PAIRAM can design and implement lighting that changes colour temperature automatically according to the time of day in the entire house. In practice, this means, for example, you can switch on a light in the morning and the lights emit a cool colour temperature of 4000–5000 K. When you switch on the lights in the evening, they are a “warm” 2700 K.
This helps strengthen our immunity and promotes healthy sleep. With correct lighting alternating between these two differences, the brain receives information about the time of day. During the day, we have enough energy, and in the evening, we can relax, which is the foundation for peaceful sleep.