Liquid crystal light control device
A liquid crystal light control device includes a first liquid crystal cell, a second liquid crystal cell overlapping the first liquid crystal cell, a third liquid crystal cell overlapping the second liquid crystal cell, and a fourth liquid crystal cell overlapping the third liquid crystal cell. Each of the first, second, third, and the fourth liquid crystal cells includes, a first substrate including a first alignment film, a second substrate including an electrode having a strip pattern and a second alignment film, and a liquid crystal layer between the first substrate and the second substrate. An alignment direction of the first alignment film and an alignment direction of the second alignment film are aligned to intersect each other. A longitudinal direction of the strip pattern of the electrode having the strip pattern is arranged to intersect an alignment direction of the second alignment film.
1 . A liquid crystal light control device comprising:
a first liquid crystal cell into which light, including a first polarized component having a first polarized axis in a first direction and a second polarized component having a second polarized axis in a second direction intersecting the first direction, is configured to enter;
a second liquid crystal cell overlapping the first liquid crystal cell;
a third liquid crystal cell overlapping the second liquid crystal cell; and
a fourth liquid crystal cell overlapping the third liquid crystal cell,
wherein
each of the first liquid crystal cell and the second liquid crystal cell includes:
a first substrate including a first alignment film having an alignment direction in the second direction;
a second substrate including an electrode having a strip pattern extending in the second direction and a second alignment film having an alignment direction in the first direction; and
a liquid crystal layer between the first substrate and the second substrate, a long axis direction of liquid crystal molecules in the liquid crystal layer aligned according to both of the alignment directions of the first and second alignment films so as to rotate horizontally from the second direction to the first direction from the first substrate side to the second substrate side,
each of the third liquid crystal cell and the fourth liquid crystal cell includes:
a first substrate including a first alignment film having an alignment direction in the first direction;
a second substrate including an electrode having a strip pattern extending in the first direction and a second alignment film having an alignment direction in the second direction; and
a liquid crystal layer between the first substrate and the second substrate, a long axis direction of liquid crystal molecules in the liquid crystal layer aligned according to both of the alignment directions of the first and second alignment films so as to rotate horizontally from the first direction to the second direction from the first substrate side to the second substrate side, and
the first substrate of one or more liquid crystal cells selected from a group of the first liquid crystal cell, the second liquid crystal cell, the third liquid crystal cell, and the fourth liquid crystal cell has a flat plate electrode, and the first substrate of any remaining liquid crystal cells have a strip patterned electrode extending in a direction intersecting the extending direction of the electrode having the strip pattern of the second substrate.
2 . The liquid crystal light control device according to claim 1 , wherein
a longitudinal direction of the strip pattern of the electrode having the strip pattern is arranged to intersect an alignment direction of the second alignment film, and
a transverse electric field is generated in the same direction as the alignment direction of the second alignment film in an ON state,
in an OFF state in which no potential is applied to the flat plate electrode and the strip patterned electrode of all of the liquid crystal cells,
the first polarized component and the second polarized component are optically rotated as passing through each of the liquid crystal layer from the first substrate to the second substrate so as to rotate the first polarized axis from the first direction to the second direction and the second polarized axis from the second direction to the first direction,
in an ON state in which a potential is applied to the electrodes of the first liquid crystal cell and the second liquid crystal cell to generate a transverse electric field in the first direction as the alignment direction of the second alignment film, and a potential is applied to the electrodes of the third liquid crystal cell and the fourth liquid crystal cell to generate a transverse electric field in the second direction as the alignment direction of the second alignment film,
in the first liquid crystal cell, the first polarized component and the second polarized component are optically rotated by passing through the liquid crystal layer from the first substrate to the second substrate so as to rotate the first polarized axis from the first direction to the second direction and the second polarized axis from the second direction to the first direction with the second polarized component diffusing in the first direction at the second substrate side,
in the second liquid crystal cell, the first polarized component and the second polarized component are optically rotated by passing through the liquid crystal layer from the first substrate to the second substrate so as to rotate the first polarized axis from the first direction to the second direction and the second polarized axis from the second direction to the first direction with the first polarized component diffusing in the first direction at the second substrate side,
in the third liquid crystal cell, the first polarized component and the second polarized component are optically rotated by passing through the liquid crystal layer from the first substrate to the second substrate so as to rotate the first polarized axis from the first direction to the second direction and the second polarized axis from the second direction to the first direction with the first polarized component diffusing in the second direction at the second substrate side, and
in the fourth liquid crystal cell, the first polarized component and the second polarized component are optically rotated by passing through the liquid crystal layer from the first substrate to the second substrate so as to rotate the first polarized axis from the first direction to the second direction and the second polarized axis from the second direction to the first direction with the second polarized component diffusing in the second direction at the second substrate side.
3 . The liquid crystal light control device according to claim 1 , wherein the electrode having the strip pattern includes at least one first strip electrode having the strip pattern and at least one second strip electrode having the strip pattern,
wherein the at least one first strip electrode and the at least one second strip electrode are arranged alternately at a distance.
4 . The liquid crystal light control device according to claim 1 , wherein the flat plate electrode is provided on the first substrate of the first liquid crystal cell.
5 . The liquid crystal light control device according to claim 1 , wherein the strip patterned electrode of the first substrate of each of the remaining liquid crystal cells has at least one third strip electrode and at least one fourth strip electrode having the strip pattern,
wherein the at least one third strip electrode and the at least one fourth strip electrode are arranged alternately at a distance.
6 . The liquid crystal light control device according to claim 1 , wherein an angle of intersection of the first direction and the second direction is 90±10 degrees.
7 . The liquid crystal light control device according to claim 1 , wherein the liquid crystal layer is a twisted nematic liquid crystal.
8 . The liquid crystal light control device according to claim 1 , wherein three of the remaining liquid crystal cells have the strip patterned electrode.
9 . The liquid crystal light control device according to claim 1 , wherein at least two of the remaining liquid crystal cells have the strip patterned electrode.
10 . The liquid crystal light control device according to claim 1 , wherein at least one of the remaining liquid crystal cells have the strip patterned electrode.