English 
Color rendering index has 15 colors, 15 color names: R1, light gray-red; R2, dark gray-yellow; R3: saturated yellow-green; R4, medium yellow-green; R5, light blue-green; R6, light blue; R7 , Light purple blue; R8, light red purple; R9, saturated red; R10, saturated yellow; R11, saturated green; R12, saturated blue; R13, white skin color; R14, leaf green; R15, yellow skin color . The average of the first 8 R1-R 8 is recorded as Ra, which is the general color rendering index (usually referred to as the light source is Ra), to characterize the color rendering of this light source; R9 means saturated red; R12 means Saturated blue.
When designing high color rendering LEDs, we must not only consider the general color rendering index Ra, but also pay attention to the special color rendering index R9 for saturated red and the special color rendering index for 4 saturated colors such as red, yellow, green, and blue. Mean R (9-12). Because the research found that the general color rendering index Ra on the color rendering evaluation of LEDs is inconsistent with the visual evaluation. In general, the white color of LED white light with a low color rendering index Ra may not be good. On the other hand, the white color of LED light with a high Ra may not be good. Only when Ra and R9 have high values at the same time can the high color rendering of LED white light be guaranteed.
In the application case of the light source, different lighting scenes have different requirements on the color rendering of the light source, but a high Ra does not mean that the lighting effect must be good. For example, for film and TV commercial supplementary lights, TV studio lighting, photography lamps and some special lighting scenes such as galleries, luxury goods, mahogany furniture, printing and dyeing factories, etc., not only the color rendering index Ra is very high, it must reach 96 or More than 97; At the same time, higher requirements for saturated red R9 and saturated blue R12 are required, which must reach 90 or more, so that the light source can be highly reducible to the person’s skin color and the natural color of the object, and will not be cast.
