When we sprinkle water droplets on a screen of a CRT television, we see spots of red, green and blue in the water droplets. A CRT lights up the screen by the means of phosphors coated on the inside surface of the screen. These phosphors are present in groups of three red, green and blue. The various colours produced on the screen are a result of by lighting the appropriate phosphors at the appropriate intensity. The water droplets allow us to see the pixels by magnifying them.