Is high CRI necessary for lighting？

What is the Color Rendering Index (CRI)?

The Color Rendering Index (CRI/Ra) measures the ability of a light source to accurately reproduce the colors of the object it illuminates.

1. CRI is a score with a maximum of 100

CRI is measured on a scale where a higher number represents higher ability, with 100 being the highest.  CRI values that are 90 and above are considered excellent, while scores below 80 are generally considered poor.

2. CRI is used to measure artificial, white light sources

Light sources can be grouped into either artificial or natural light sources. In most situations, we are concerned about the color quality of artificial forms of lighting, such as LED and fluorescent lamps. This is compared to a daylight or sunlight - a natural light source.

3. CRI measures and compares the reflected color of an object under artificial lighting

When we use an artificial light source such as an LED lamp, we are attempting to "reproduce" the colors of natural daylight such that objects appear the same as they do under natural daylight. The closer the Ra value is to 100, the better the color rendering of the light source, and the smaller the difference between the color presented by the illuminated object and its "original color".

What are the hazards of poor CRI?

1. If one is exposed to a light source with poor CRI for a long time, it can lead to a decline in one's ability to distinguish colors, leading to serious visual problems and eye diseases such as color blindness and color weakness.
2. The sensitivity of cone cells in the human eye will also decrease, and the brain will intentionally or unintentionally concentrate more when distinguishing things, which can easily lead to eye fatigue and even myopia.

What is the appropriate CRI for selecting LED lighting fixtures?

1. For most indoor and commercial lighting applications, 80 CRI (Ra) is the general baseline for acceptable color rendering.
2. For the selection of outdoor lighting, CRI≤70 are generally used
3. For applications where color appearance is important for the work being done inside, or can contribute to improved aesthetics, 90 CRI (Ra) and above can be a good starting point.
4. Types of applications where 90 CRI (Ra) might be needed for professional reasons include hospitals, textile factories, printing facilities or paint shops.