LED Terminology Defined: Binning

LED Technology is not just about efficiency, power and light color temperature. Luminous flux performance over lifetime and color rendering index, accordingly the spectrum, are important as well. A lot of people recognize cheap LED versions in any shops or retail stores that seem to be bluish and illuminate the space quite palely.

The reason is the grouping and choice of LEDs. What does that mean?

The manufacturing process is accompanied by variations in material and action itself. The results are white light LEDs with different characteristics. Binning systems have been introduced to support the performance of LEDs and LED products. Binning is focusing on LEDs chromaticity (light color) or luminous flux (brightness) and can be described as the grouping of the LEDs into samples with the same or closest light color or brightness.

Introducing MacAdam Ellipses:

Binning_CIExy1931_MacAdam_wickimediadotorgDavid MacAdam, a color scientist, introduced his research on human color perception mid of the 20th century. He examined color differences in visual observations and mapped them into a color space.  MacAdam’s observers tended to cluster similar colors as “nearly same ones”. When MacAdam measured the chromaticity of the cluster, they formed ellipses in the color diagram. The MacAdam ellipses are representing the area that is just noticeable to be different from the original light source, indicated as black point in the picture on the left.

Binning systems manage variations in LED performance like chromaticity and luminous flux during mass production. The decision for a small binning or a lot of LED Chips with the same/ nearly same specification will lead to higher costs as all the other LED dies of the same manufacturing sample are hard to sell to other customers. Read the full story about the topic in one of our White Paper – LED Light Color – Binning System.

In a nutshell, recent studies tested different compositions of lighting spectra and found an influence on human condition. People who are sensitive to their surroundings tend to complain about headache, dizziness and even nausea when exposed to imbalanced spectra. Long term exposition is even expected to have a negative impact on human health. When buying LED light sources, retrofit kits and products have a look at the CRI or spectrum. The more balanced, the better for the people working under it.