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LED color tolerance international standard analysis
- May 23, 2018 -

Color Tolerance: Characterizes the difference between X and Y values calculated by the software of the light-colored electrical detection system and the standard light source. The smaller the value, the closer the light color coordinate of the product is to the standard value. The smaller the difference between the spectrum emitted by the light source and the standard spectrum is, the higher the accuracy is and the more pure the light color is.

 

McAdam ellipse theory: In 1942, scientist McAdam experimented with 25 colors using related principles, measured in about 5 to 9 contralateral directions for each color point, and recorded that they were just able to distinguish the two-point distance when the color was different. The result is a number of ellipses with different sizes and different lengths and short axes, called MacAdam ellipses. The McAdam ellipse is usually described in terms of “orders,and the term orderhere refers to the standard deviation. The 1st-order MacAdam ellipse refers to the standard deviation of the change in the color matching result that is 1 times the target color. Similarly, the meaning of 3rd-order, 4th-order, etc. is known.

 

Color tolerance main standard category

At present, the main domestic color tolerance standards are North American ANSI standards, IEC, and EU standards.

 

Industry standard level:

1. Energy Star ANSI C78.376, color tolerance ≤ 7 SDCM, divided by characteristics.

2. The EU standard ERP, color tolerance ≤ 6 SDCM, according to the technical requirements to standardize the LED division.

3. National standard GB10682-2002, double-end fluorescent lamp performance requirements color tolerance ≤ 5 SDCM, can be used as a reference for LED lamp color tolerance.

 

Difference between color tolerance and color difference

Chromatic aberration: The difference in color, that is, the difference between the X and Y coordinate values of the two light colors. The smaller the difference is, the smaller the color difference is.

Color tolerance: Characterize the difference between the X and Y values of the product and the standard light source X and Y. The smaller the distance, the smaller the color tolerance.