Color classification and characteristics

The whole process by which a person feels color is: light is reflected on a colored object. The reflected light or transmitted light is accepted by the human eye and is recognized by the brain. The four factors that produce color perception can be divided into two parts: objective stimulus (light source, color (Objects) and subjective feelings (eyes, brains), they are unified in the process of formation of color perception, both exist at the same time and are indispensable.
Color can be divided into color and non-color. Non-color means white, black, and shades of gray. They form a series, from white to light gray, medium gray to dark gray, until black, known as black and white series. Pure white is an ideal total reflector with a reflectivity of 100%; pure black is an ideal reflector-less reflector with a reflectivity of zero.
In nature, such pure white and pure black do not exist. Therefore, it is stipulated that when the reflectance of the surface of the object to visible light is 80 to 90% or more, the object is white; when its reflectance is at 40/ Below 0, the object is white; when the reflectance is below 40/0, ​​the object is black. All colors other than color are called color.