Color Rendering Index
What is CRI?

English: International Commission on illumination

French: Commission Internationale de l´Eclairage(CIE 1974)

 

The Color Rendering Index (CRI) is a quantitative measurement of how accurately a light source represents the colors of objects compared to a natural or ideal light source. The highest possible CRI is 100, with most LEDs having a CRI of around 80 or higher, and some can achieve a CRI of up to 90, 95 or more. However, achieving a higher CRI may come at a cost, as the lumen output may decrease by around 15%.

Compare the test color with 8 standard color
Only sunlight, Ra=100
R9
• Represents how accurately a light source will reproduce strong red colors.
• R9 is not included in CRI value and need be specified separately
CRI is not enough, standard updated
CRI-CIE(1974)
One value:
CRI-Color Rendering Index

CRI=Measures fidelity Based on the Average number of R1-R8 scores
Pay special attention to:
-R9 for saturated reds
-R13 and R15 for skin tones

Well stablished industry standard

Limited to just 8 pastel tones
Penalizes saturated colors

TM-30-IES NA(2015)
Two values:
Rf-Fidelity Index
Rg-Gamut Index

Rf , Rg=Measures fidelity and gamut based on 99 colors samples.
Gamut allows you to understand the color saturation vs the reference source

The two index values indicates
more fairly the color performance

Not fully adopted
New metrics can create confusion

What Rf and Rg Value Is Ideal for Supermarket Food?
Ideal Rf and Rg value
Boundary of Rf and Rg
Different CCT for Different Goods

The color temperature of a light source refers to the temperature of an ideal black-body radiator that emits light of a similar hue to that of the light source. It is measured in Kelvin (K). Lower Kelvin values typically result in a "warmer" light that appears yellow, orange, or red, while higher Kelvin values produce a "cooler" light that appears bluish.

Fruit
3000K
Vegetables
4000K
Seafood
6500K
Bread
2700K
Dairy & Daily
6500K