Circadian Lighting

Sleeping Soundly


Most animals and other organisms have “built-in clocks” in their brains that regulate the timing of biological processes and daily behaviour. These “clocks” are known as circadian rhythms. They allow maintenance of these processes and behaviours relative to the 24-hour day/night cycle in nature

The concept of circadian lighting follows that of the human circadian rhythm, a 24-hour internal clock. The area of the brain called the hypothalamus controls each person’s circadian rhythm by receiving signals from the eyes that report when it’s daytime and nighttime. The hypothalamus, in turn, controls the amount of melatonin released to correlate sleepiness with darkness and alertness with lightness.


Intensity tuning is the most familiar and cost-effective solution to circadian lighting. Fixtures maintain a fixed correlated colour temperature (CCT) while the intensity (brightness) of the fixture is adjusted, through a controlled dimming system, to correlate with the time of day. Light fixtures are set to a lower intensity in the early morning, the transition to higher intensity as the day progresses, and reduce to a lower intensity in the evening.

Colour tuning involves changing the light intensity and CCT to mimic the daytime/nighttime cycle. We experience cooler colour temperatures (ranging from 4000K up to about 10,000K) when the sun is highest in the sky and people are typically most alert during the day. Therefore, cooler CCTs are used in spaces and during times when it’s appropriate to promote alertness and attention. Warmer colour temperatures (ranging from < 2700K to 3500K) represent daylight hours when the sun is rising and setting when people are falling asleep or waking up. Circadian lighting systems are set to adjust based on the CCT we typically observe at any given time of the day.

Stimulus tuning is lighting technology that replaces the “bad blue” with “good blue” light wavelengths. This circadian lighting approach more closely mimics the daylight spectrum. Stimulus tuning light fixtures can be programmed to reduce blue light wavelengths during the evening/nighttime hours to limit melatonin suppression without changing the CCT. Similar to colour tuning, this lighting approach is most effective when paired with intensity tuning.


By integrating all these aspects into our lighting engine. We are able to provide a luxurious circadian lighting system. Get all the benefits of our light systems, with the added benefit of automated light tuning, colour correction, and dimming to fit your circadian patterns. Perfect for the bedroom or the office.