Birefringent Cell
AssigneeEnvisics Ltd
InventorAntariksh Saxena
Life of this patent
Estimating the term…
Abstract
Disclosed embodiments include an electrically-controlled birefringence cell comprising: (i) a nematic liquid crystal in a planar configuration between a plurality of pixel electrodes and a common electrode; and (ii) an alignment layer configured to impart a pretilt on the nematic liquid crystal in contact with the alignment layer, where the pretilt has a pretilt angle in a range of about 5 to 25 degrees, where a surface anchoring value between the nematic liquid crystal and the alignment layer is less than about 1 mJ/m2, and where the electrically-controlled birefringence cell exhibits a low phase retardance variation when a voltage is applied through the alignment layer to the nematic liquid crystal.
Claims20
A system comprising:
- an electrically-controlled birefringence cell comprising:
- (i) a nematic liquid crystal in a planar configuration arranged between a plurality of pixel electrodes and a common electrode, wherein a cell gap between the plurality of pixel electrodes and the common electrode is no more than about 20 micrometers;
- and (ii) an alignment layer configured to impart a pretilt on the nematic liquid crystal in contact with the alignment layer, wherein the pretilt has a pretilt angle in a range of about 5 to 25 degrees, wherein a surface anchoring value between the nematic liquid crystal and the alignment layer is less than about 1 mJ/m2, and wherein when a voltage is applied through the alignment layer to the nematic liquid crystal, the electrically-controlled birefringence cell exhibits a lower phase retardance variation between an individual pixel electrode and the common electrode as compared to a birefringence cell comprising a nematic liquid crystal in a planar alignment configuration arranged between a plurality of pixel electrodes and a common electrode having (a) an alignment layer arranged to impart a pretilt of less than about 5 degrees on nematic liquid crystal in contact with the alignment layer, and (b) a surface anchoring value of more than about 1 mJ/m2 between the nematic liquid crystal and the alignment layer.
A method of fabricating an electrically-controlled birefringence cell comprising a nematic liquid crystal in a planar alignment configuration arranged between a plurality of pixel electrodes and a common electrode, wherein the electrically-controlled birefringence cell has a cell gap of no more than 20 micrometers and an alignment layer in contact with the nematic liquid crystal, wherein the method comprises:
- processing the alignment layer to (i) impart a pretilt on the nematic liquid crystal in contact with the alignment layer, wherein the pretilt has a pretilt angle in a range of about 5 to 25 degrees and (ii) achieve a surface anchoring value between the nematic liquid crystal and the alignment layer of less than about 1 mJ/m2;
- and
- wherein processing the alignment layer to impart the pretilt angle in the range of about 5 to 25 degrees and achieve the surface anchoring value of less than about 1 mJ/m2 causes the electrically-controlled birefringence cell to exhibit a lower phase retardance variation between an individual pixel electrode and the common electrode when a voltage is applied through the alignment layer to the nematic liquid crystal as compared to a birefringence cell comprising a nematic liquid crystal in a planar alignment configuration arranged between a plurality of pixel electrodes and a common electrode having (i) an alignment layer arranged to impart a pretilt of less than about 5 degrees on nematic liquid crystal in contact with the alignment layer, and (ii) a surface anchoring value of more than about 1 mJ/m2 between the nematic liquid crystal and the alignment layer.
Dependencies are inferred from the claim text.