Posted by Doug Root on April 14, 2016
The light bulb has changed dramatically in the past few years. Edison would be completely surprised with the speed that technology these days. An area that did not exist in his life time was varying color temperatures. Light bulbs were heated filaments that gave off CCT (correlated color temperature) of around 2700K or soft/warm white. Now, LED lighting offers many benefits and features that were difficult, if not impossible to offer with traditional incandescent light bulbs. The benefits of LED bulbs are fairly well known. The big ones being energy reduction, maintenance cost reductions, longer life and cooler operating temperatures. One that is greatly overlooked is the ability of this SSL or solid state light be dialed into the exact color temperature that you would like.
Measuring Lighting Color Temperature
The color of the light that we see with our eyes varies based on the rated CCT of the LED light module. The measurement of the hue of "white" light started in the late 1800s, when the British physicist William Kelvin heated a block of carbon. The block of carbon changed color as it was heated up, going from a orange-red, through various colors of yellow, all the way up to a bright blue white at its highest temperature. The measurement scale for color temperatures, which was named after Kelvin as a result of his work, was based on Centigrade measurements.
LED Color Temperature
The term used in general illumination is correlated color temperature (CCT). CCT is a measurement of the color of light produced by a particular light source, and uses the Kelvin temperature measurement scale to measure it with. The scale describes the relative color appearance of a white light source, indicating whether it appears more yellow ("warm") or more blue/white ("cool"), in terms of the range of available shades of white.
Many people are now familiar with the idea of a "warm" white or a "cool" white that we have seen used over the years in fluorescents and CFL's. Fluorescent technologies come in an array of different color temperatures. The "warm" white has a color temperature of 3,000K and casts a more orange/reddish light on surfaces and objects. Society normally associates warmth with red/yellow/orange objects, this is where the "warm" name comes from, even though it is a cooler (lower) temperature on the Kelvin scale(2700-3000K). A "cool" white bulb commonly has a color temperature of 4,100K and is higher on the Kelvin scale. This is in the low range of blue color or daylight(6500K), this color is similar to therefore earning the "cool" description.
The most popular color temperature that we see in LED's is the 5000K or "balanced white light" as we like to call it. This color temperature is perfectly nuetral and white on the scale and has minimal yellows or blues. This is why many LED manufacturers have begun to produce two CCT lamps in each version. Most offer a warm white 2700K or a white light 5000K.
Color temperature can be measured simply using a handheld meter. The reading can be taken in seconds with the press of a button. When the button is pressed, readings are taken from a group of sensors (blue, green, and one of two red light sensors behind the shield) and processed through algorithms to produce a Kelvin temperature reading that can be used for photography, verification, or simple reference purposes.
Choosing Color Temperatures
With so many choices now in lighting color temperatures, the questions that often arise are: "How do I know what color temperature I should choose? Should I have a certain color temperature in my warehouse, a particular color temperature in my offices or my house, and then a specific color temperature in my entry area?" In most instances the answer may be the same color temperature for all of those applications. The reason being is we see many times lamps are mixed up in the storeroom and you have a mixture of colors in the same area which can look bad. Commercial customers that want different moods for areas of their building do so by zoning and labeling the areas for the maintenance team so that the correct CCT goes in the room.
COLOR TEMPERATURE AND PURPOSE
Color temperature in a room or space greatly affects on the people that use that lighting to perform tasks. For example, rooms that are used for tasks such as reading or looking at detailed instrumentation can benefit by incorporating lighting on the cooler end of the scale. However in an office area with many screens, you will want to use a warmer color with lower light levels so that the glare on the screen does not give the user headaches. Many studies have been done on classroom and work settings where reading improves when done under lighting near 5500K (Day White - 5500-6000K).
So if you want to dial in the right color temperature for your home or office, call the specialist here at AtlantaLightBulbs.com. We can help you pick the right color. Read more about CCT here