LED Answers: Color Temperature
2nd Feb 2016
LED technology has come a long way in the past few years. While the benefits of LED are apparent – energy efficiency, longer life and lower heat generation – many are left scratching their heads when it comes to answering questions about color temperature in LEDs. So much so that it may detract us from making the switch, in fear of the unknown. Here we lift the veil on color temperature of LEDs giving you the tools to make the correct decision for your needs.
The History of Kelvin
Measuring the hue of light started in the late 1800s when British physicist William Kelvin discovered the color change that occurred when he heated a block of carbon. Starting from a dim red, through shades of yellow and up to a bright blue at the hottest temperature. This discovery resulted in a scale named after Kelvin that measures the color of the light in relationship to the centigrade degrees that produces the color.
Correlate Color Temperature (CCT)
CCT is the color of light produced by a light source and uses the
Kelvin measurement scale. CCT indicates whether a light appears more
yellow – warm – or more blue – cool. A warm colored bulb often has a CCT
of 3,000K while a cool white bulb commonly has a CCT of 4,100K or
higher. Counter intuitively, the hotter the light, the cooler the color
Some benchmarks to note include: 2800K is what we know to be a common incandescent light bulb, while direct sunlight is commonly 4800K.
Depending on personal preference, as well as how the lit space will be used, differing ideals will arise when trying to choose the right LED. Classrooms and warehouses benefit from bright white light on the cooler end of the color spectrum (5500-6000K) while wood toned interiors benefit from a warmer natural white light (4000-4500K). Restaurants almost always need lower Kelvin settings to maintain ambiance. Along with function and mood of a space, colors used in décor should be taken into account when choosing the right light quality. Warm colors will look more saturated when lit with warm white light, while blues and greens will pop in cooler white light qualities. If a mix of colors exist in a room, a natural white light (4000-4500K) is ideal. Ultimately, a careful consideration of function and personal preference must be made before choosing a white light quality for a home or business, and educating yourself on exactly what all those numbers mean is the first step in the right direction.