2. If the mathematical vector space is used to explain the color system, then the primary colors can be used as a set of basis vectors in the space and can be combined into a "color space". The color space seen by naked eyes usually consists of three basic colors, which are called "three primary colors". Generally speaking, the superimposed three primary colors are red, green and blue; The subtractive primary colors are magenta, yellow and cyan. In the traditional pigment coloring technology, red, yellow and blue are usually regarded as primary colors. Modern art books no longer use this statement, but adopt subtractive primary colors. )
3. Generally speaking, the colors used in light source projection belong to the "superimposed" primary color system, including the three primary colors of red, green and blue, also known as the "three primary colors". Using these three primary colors can produce other colors. For example, mixing red and green can produce yellow or orange, mixing green and blue can produce cyan, and mixing blue and red can produce purple or magenta. When these three primary colors are superimposed in equal proportion, they will turn gray; If the intensities of these three primary colors are all adjusted to the maximum and overlap equally, they will appear white.
4. This primary color system is usually called "RGB color space", which is a color system composed of red (R), green (G) and blue (B).