Do You Really Understand Chromaticity of LED Display Screen
People who do lighting are definitely not familiar with the color rendering parameter. But do you really know about it? Today we'll talk about color rendering. Before we talk about color rendering, let's start with a few scenes of life that everyone will encounter.
The following two plates of iron plate string, which do you want to eat more?
Everyone should be able to observe that under the different light sources, the same plate of iron plates string together, the color is very different! This involves the color of the light source of the problem!
What is the color rendering of the light source?
The chromaticity of light source refers to the degree of presentation of light source to the natural primary colors of objects. That is the degree of color fidelity, usually called Ra. Chromaticity can be classified into two types: "faithful color development" and "effect color rendering".
The international lighting Committee (CIE) set the color rendering index of sunlight to 100, and specified 15 test colors. The index of these 15 colors was expressed by R1-R15. When a light source is compared with the prescribed reference light source, the index value of 100 is the best.
What about R1-R15?
So many colors! What is the meaning of it? In fact, every light source has a relatively sensitive color, for example, a light source is more sensitive to red. Then, under its irradiation, the color of the red object will be more true, but the other colors are not necessarily able to reach it. To a very real color reduction effect.
In terms of the specialty, the evaluation of the color rendering property of the light source is mainly about the reduction level of the R1-R8 8 natural colors, the R9-R15 7 test colors and the total 15 colors, while the Ra we usually talk about is the mean value of the light source to the 8 natural color reduction levels of the light source, and the R9-R15 is not calculated.
We usually see similar marking methods such as Ra>90 (R9>50) and so on. Ra>90 shows that the color display of the luminaire has high degree of reduction for 8 natural colors of R1-R8. R9>50 shows that the luminaire has a good color reduction ability to red objects.
How to choose the luminaire for the color of the goods?
The choice of the appropriate illuminating light source is mainly determined by the color of the object. For example, in the three sets of contrast images at the beginning of the article, the iron plate on the left has used a light source with a higher R9 color index, so it looks more luster; the red skirt on the left is also a light source with a higher R9 color index, so it looks color. It is brighter and brighter; while the fruit on the left supermarket has a good color index because of its Ra, it looks more coveted.
The R9 color index is particularly important for the light source of the meat shop window in supermarkets and stores, and the R15 index of the lighting source must not be low for the studio, the studio and other occasions where the color of the skin needs to be reproduced, and the museum, the art gallery and other places require a high true reduction of the colors, Ra and R1. The demand for the -R15 index is more stringent.
