The Active Matrix LCD is an improvement on the standard
LCD; Thin film transistors and capasitors are mounted
on a substrate of glass, arranged in a matrix. This
glass substrate is one of the sides in the display and each
transistor/capacitor circuit is a pixel. To address one
pixel you turn on the row and coloumn its on. This opens the
transistor and the charge from the coloumn line is stored in
the capacitor. This capacitor holds the charge until the next cycle.
This means that the display is almost flicker free.
By controlling the charge we can make a grayscale picture.
If we add colour filters so that the first coloumn is red, the next green
and the third blue and so on, we get a colour display. This LCD
type is some times called thin film transistor LCD(TFT LCD).