Additive color

Additive color is color created by mixing a number of different light colors, with Red, green, and blue being the primary colors normally used in additive color system.

Additive color is in contrast to subtractive color, in which colors are created by subtracting (absorbing) parts of the spectrum of light present in ordinary white light, by means of colored pigments or dyes, such as those in paints, inks, and the three dye layers in typical color photographs on film.

The combination of two of the standard three additive primary colors in equal proportions produces an additive secondary color—cyan, magenta or yellow—which, in the form of dyes or pigments, are the standard primary colors in subtractive color systems. The subtractive system using primaries that are the secondaries of the additive system can be viewed as an alternative approach to reproducing a wide range of colors by controlling the relative amounts of red, green, and blue light that reach the eye.

Computer monitors and televisions are the most common examples of additive color. Examination with a sufficiently powerful magnifying lens will reveal that each pixel in CRT, LCD and most other types of color video displays is composed of red, green and blue sub-pixels, the light from which combines in various proportions to produce all the other colors as well as white and shades of gray. The colored sub-pixels do not overlap on the screen, but when viewed from a normal distance they overlap and blend on the eye's retina, producing the same result as external superimposition.