In-plane switching electrophoretic colour display

Abstract

The invention relates to an electrophoretic color display panel, the display panel comprising at least one pixel (10, 12), the at least one pixel (10, 12) comprising a layer cavity (18ab) containing a suspension with a first set of charged particles (24a) having a first optical property and a second set of charged particles (24b) having a second optical property, and a pair of control electrodes (20a, 20b) arranged adjacent to the layer cavity (18ab), such that charged particles (24a, 24b) are essentially in-plane displaceable in an in-plane direction within the layer cavity (18ab) upon application of a control voltage over the electrode pair, wherein the in-plane distribution of charged particles (24a, 24b) having first and second optical properties in the layer cavity (18ab) depends on at least one of a differing control property additional to any polarity difference of the charged particles (24a, 24b) for each set of charged particles, or at least one additional electrode arranged adjacent to the layer cavity, wherein the electrode pair (20a, 20b) and the at least one additional control electrode are arranged essentially outside of a viewing area (26) of the at least one pixel (10, 12), such that a composite optical property of at least a portion of the at least one pixel (10, 12) is controllable. According to the invention, the control electrodes will be arranged at essentially the outer ends, or arranged in-plane, at a peripheral, of a prolonged layer cavity, such that the particles move in an in-plane direction within the layer cavity when the control voltage is applied. This facilitates the handling of the pixel since the layer cavity can be reached from essentially the outside of the pixel. Another advantage is that since only a minor part of the pixel area has to be covered with an electrode material the total transmission and thus the brightness of the pixel can be optimized.

Dependencies are inferred from the claim text.