This leads to the principals of color addition. Color addition involves combining different colors or wave lengths of light to form a new color of light. For instance, a combination of Red and Blue light result in the color Magenta. Red and Green forms the color Yellow and Blue and Green light result in the color Cyan. This is outlined in the following figure.

Color Subtraction

Color Subtraction involves eliminating one or more wavelengths of light so that a new color of light is emitted. We know that White light consists of Red, Green, and Blue light waves. If the incident light is white (R + G + B), and we eliminate the Blue light, the resulting color of light is yellow (R + G + B – B = R + G = Yellow).

If the incident light is Cyan (B + G) and the Blue light is subtracted, the resulting light would be Green {C - B = (G + B) - B = G}. This would occur if a surface were capable of absorbing the Blue light waves and is depicted below.