For this kind of LCD's, transparent conductive lines for the rows and columns are applied to the glass above and below the Liquid Crystal material. The brightness of the cells are controlled sequentially line by line. The Crystals are aligned by applying a voltage to a cell for a short time. They begin to loose this alignment when the next line is controlled. This kind of scheme can cause a lot of flicker, so LC material that has a slow response time is used - that means after the crystal is aligned by the field, as it takes a long time to return to its unaligned state. The slow response means that fast moving objects will show some 'smearing' on the screen.