White Tunable Lighting
What is white tunable lighting?
White tunable, also known as color tunable, lighting is white lighting that can be adjusted across a range of color temperatures. See the “Color Temperature” page for more information about the definitions of white light terms.
How is it possible to change the color temperature of a white light?
In strip lighting, diodes often alternate between warm white and daylight white. They are controlled together so that as one dims the other gets brighter, resulting in a smooth fade. Other methods include having two monochrome strips next to each other, controlled in the same way, or placing multiple temperatures of white within a single bulb.
What is the benefit of changing the color temperature of a white light?
Each type of lighting has different effects on the ambiance of an area and the people within it. Warm light promotes relaxation, whereas daylight white promotes energy and focus. Individuals diversely along the spectrum of white light, and studies have shown that providing individual workers with tunable lighting at their desks or offices not only increases productivity but also decreases rates of headaches and migraines.
Why does color temperature affect people?
For all of human history before about 150 years ago, most lighting came from the sun. At the beginning and end of the day, the color temperature is warm, the rest of the time it is cool. Photoreceptors in the eyes became accustomed to this pattern and the circadian rhythm became linked to this cycle. Research has shown that the color temperature of light can increase or decrease production of hormones. For example, a Rensselaer Polytechnic Institute study measured the amount of light received by the eyes of a number of volunteers who used tablet devices, which output very cool hues of white to create bright effects,. They found that two hours of exposure at night reduced melatonin levels in the body by about 22%. In other studies, schools using warm light for the first part of the morning and to calm students directly after recess breaks, and cool white the rest of the day have shown increased focus and concentration.