Koninklijke Philips Corporation N.v.

Michael Geoffrey Pitt

Peter Van De Witte

Mark Thomas Johnson

Guo-Fu Zhou

Alexander Victor Henzen

An electrophoretic display device () comprising one pixel () with an electrophoretic medium (), electrodes (), as well as drive means () by which the pixels can be brought into different optical states. Some time (thold) after the application of an addressing pulse (Paddress) for setting the brightness level (Rw, Rb) of a pixel (), a restore pulse voltage (Prestore) is applied between the electrodes () for restoring the brightness level of a pixel to the set level (Rw, Rb). The restore pulse may be a set of consecutive pulses to bring the drifted brightness level even more smoothly (i.e. less perceivably) back to the original brightness level.

Electrophoretic display device and driving means for restoring the brightness level

In a method of manufacturing a liquid crystal device including a layer having a fixed cholesteric order, the patterned layer is manufactured by providing a layer comprising polymerizable cholesterically ordered material and a compound convertible by means of radiation from a non-converted to converted state. The pitch of the cholesterically ordered material is influenced by the compound in its converted state to a different extent than in its converted state. The polymerizable layer is then irradiated pattern-wise thus creating regions of different pitch. The irradiated layer is then polymerized and/or cross-linked to fix the cholesteric order thus obtained.

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Heerlen, Netherlands

Michael Geoffrey Pitt