RGB Model

The RGB model is based on the assumption that any desired shade of colour can be obtained by mixing the correct amounts of red, green, and blue light. The exact hues chosen are not important as long as they include a long wavelength hue (red), a medium wavelength hue (green), and a short wavelength hue (blue). If, for instance, circular red, green, and blue beams are projected onto a white screen in a darkened room, we get the colour pattern.

The additive nature of the RGB model is very apparent. Adding red, green, and blue light produces white light, while adding red and blue light produces magenta light, and so on. This linear superposition is expressed mathematically as :

    C= rR + gG + bB