Patent ID: 7999832

Claim:
A bistable matrix-addressable display element comprising a substrate, a bistable electrically modulated imaging layer, at least one conductor, and at least one field-spreading layer adjacent to said bistable electrically modulated imaging layer and adjacent to said at least one conductor, wherein said field-spreading layer has a sheet resistance (SER) of from 10 9 to 10 6 Ohms per square; the bistable matrix-addressable display element comprises an area to be updated, wherein said area to be updated comprises rows of pixels; and the bistable matrix-addressable display element is imaged by applying a sequence of drive signals having a 4-phase approach, wherein said 4-phase approach comprises: in phase 1, applying a first pixel voltage across said pixels of said area to be updated such that the critical voltage is reached; and holding said first pixel voltage until a homeotropic texture is reached; in phase 2, setting a second pixel voltage to allow said homeotropic texture to relax into a stable planar texture; in phase 3, selecting one row of pixels of said rows of pixels of said area to be updated; and updating said one row of pixels by addressing, wherein addressing comprises applying a third pixel voltage, capable of switching said pixels from said stable planar texture to said non-reflective focal conic texture, across said pixels to produce switched pixels; applying a fourth pixel voltage, incapable of switching said pixels from said stable planar texture to said non-reflective focal conic texture, to produce unswitched pixels to remain in the stable planar texture; and repeating said addressing until said rows of pixels of said area to be updated have been addressed; and in phase 4, removing said first pixel voltage, said second pixel voltage, said third pixel voltage, and said fourth pixel voltage from said area of said bistable matrix-addressable display element to be updated.