Electrophoretic display and driving method thereof

A method of driving an electrophoretic display comprising a plurality of pixels and barrier walls defining the pixels and formed between opposing first and second substrates, a pixel of the plurality of pixels containing a plurality of positive charged particles and a plurality of negative charged particles both positioned between a first electrode formed on a horizontal surface of the first substrate and a second electrode that is spaced apart from the first electrode and formed on a vertical surface of a barrier wall of the barrier walls, wherein the vertical surface of the barrier wall and the second electrode extending not parallel to the horizontal surface of the first substrate, and each of the positive charged particles and the negative charged particles has at least two threshold voltages, the method comprising:

• positioning the positive charged particles and the negative charged particles next to the second electrode to be entirely covered by an upper light blocking layer when substantially no grayscale voltage is applied to the first and second electrodes;
• positioning the negative charged particles over the first electrode and positioning the positive charged particles next to the second electrode to be entirely covered by the upper light blocking layer by applying a first grayscale voltage to the first and second electrodes, the first grayscale voltage having a magnitude greater than an attractive force threshold voltage of the negative charged particles;
• positioning the negative charged particles and the positive charged particles next to the second electrode to be entirely covered by the upper light blocking layer by applying a second grayscale voltage to the first and second electrodes, the second grayscale voltage having a magnitude greater than a repulsive force threshold voltage of the negative charged particles and lower than an attractive force threshold voltage of the positive charged particles;
• positioning the positive charged particles over the first electrode and positioning the negative charged particles next to the second electrode to be entirely covered by the upper light blocking layer by applying a third grayscale voltage to the first and second electrodes, the third grayscale voltage having a magnitude greater than the attractive force threshold voltage of the positive charged particles;
• positioning the negative charged particles and the positive charged particles next to the second electrode to be entirely covered by the upper light blocking layer by applying a fourth grayscale voltage to the first and second electrodes, the fourth grayscale voltage having a magnitude greater than the repulsive force threshold voltage of the positive charged particles and lower than the attractive force threshold voltage of the negative charged particles;
• and
• displaying at least one of black and white using an opaque material layer that is disposed on the first electrode and completely covers the first electrode, wherein the opaque material layer and the upper light blocking layer together cover an entire area of a pixel.