Patent ID: 8130186

Claim:
A liquid crystal device comprising: first and second cell walls; a layer of liquid crystal material disposed between said first and second cell walls, said layer of material being capable of adopting and being electrically latched between at least two stable configurations, said layer of material comprising at least one pixel, said at least one pixel comprising at least one electrically addressable region, each said region comprising: a first sub-region arranged to have a latching threshold within a first range; and a second sub-region arranged to have a latching threshold with a second range, said second range differing from said first range; and addressing means for writing to each of said at least one region using voltage pulses to selectively latch said layer of material as required, wherein the addressing means is arranged to write to each said region using at least first and second latching scans, the first latching scan arranged to selectively latch substantially all material in said first sub-region into any one of said at least two stable configurations and the second latching scan arranged to selectively latch substantially all material in said second sub-region into any one of said at least two stable configurations, the configurations of said first and second sub-regions are independent of each other, wherein said first latching scan additionally comprises a blanking waveform to latch all of said material of said region into one of said at least two stable configurations prior to the selective latching of all material in said first sub-region, wherein said first latching scan is applied prior to application of said second latching scan and said second latching scan is insufficient to latch material of said first sub-region.