Colour rendering index (CRI) is typically more important for commercial or artistic applications where precise colour rendering is important. A light bulb with perfect colour rendering has a CRI of 100.

A high CRI reflects the ability of a light source to accurately render the colours of an illuminated object such as retail products, skin tones or other materials. However, subjectively such variations in CRI are not always subjectively noticeable and often it is highly dependent on the colour tones of the object and the choice of colour temperature.In fact there are many RGB-based LED light products that have CRIs in the 20s, yet the light appears to render colours well.[1] Also differences in CRI values of less than five points are not significant such that LED light bulbs with 80 and 84 CRI are essentially the same.

We have seen some older 2008-2009 design bulbs from major manufacturers that have very poor colour rendering due to a spike in their spectral power distributions. This is where there is an unusually high peak within a particular wave length, usually pink tones, leading to a pinkie tinge to the light. As a result at Lite On LED we screen our bulbs for this distasteful effect.

Today’s modern LED light bulbs typically have a CRI of between 75 and 80 which is more than adequate. CRI of 90 and higher is available for some LED light bulbs by special order.