Compensators for liquid crystal displays and the use and manufacture of the compensators
Compensation of a liquid crystal display can be achieved using a compensation structure, having, in the following order: a) a first o-plate; b) a first retarder; c) a liquid crystal cell; d) a second retarder; and e) a second o-plate. The first and second retarders can be c-plates or biaxial retarders.
1. A liquid crystal display, comprising:
a first positive o-plate;
a first retarder;
a liquid crystal cell, wherein the first retarder is disposed between the first o-plate and the liquid crystal cell;
a second retarder, wherein at least one of the first and second retarders is a biaxial retarder; and
a second positive o-plate, wherein the second retarder is disposed between the second o-plate and the liquid crystal cell.
2. The liquid crystal display of claim 1 , wherein both the first and second retarders are biaxial retarders.
3. The liquid crystal display of claim 1 , wherein one of the first and second retarders is a c-plate.
4. The liquid crystal display of claim 1 , wherein the biaxial retarder has a negative out-of-plane birefringence.
5. The liquid crystal display of claim 1 , further comprising a first o-plate positioned so that the first o-plate is between the first o-plate and the liquid crystal cell.
6. The liquid crystal display of claim 5 , further comprising a second o-plate positioned so that the second o-plate is between the second o-plate and the liquid crystal cell.
7. A liquid crystal display, comprising:
a first o-plate;
a first retarder;
a liquid crystal cell, wherein the first retarder is disposed between the first o-plate and the liquid crystal cell;
a second retarder, wherein at least one of the first and second retarders is a biaxial retarder;
a second o-plate, wherein the second retarder is disposed between the second o-plate and the liquid crystal cell; and
a first c-plate positioned so that the first o-plate is between the first c-plate and the liquid crystal cell.
8. The liquid crystal display of claim 7 , further comprising a second c-plate positioned so that the second o-plate is between the second c-plate and the liquid crystal cell.
9. The liquid crystal display of claim 7 , wherein both the first and second retarders are biaxial retarders.
10. The liquid crystal display of claim 7 , wherein one of the first and second retarders is a o-plate.
11. The liquid crystal display of claim 7 , wherein the biaxial retarder has a negative out-of-plane birefringence.
12. A liquid crystal display, comprising:
a first o-plate having a first azimuthal orientation;
a first c-plate;
a liquid crystal cell comprising a rear surface and a front surface, wherein the liquid cyrstals at the rear surface have a second azimuthal orientation and the liquid crystals at the front surface have a third azimuthal orientation and wherein the first o-plate is disposed between the first o-plate and the liquid crystal cell;
a second o-plate;
a second o-plate having a fourth azimuthal orientation, wherein the second o-plate is disposed between the second o-plate and the liquid crystal cell; and
a third o-plate positioned so that the first o-plate is between the third o-plate and the liquid crystal cell and a) the first and second azimuthal orientation, b) the second and third azimuthal orientation, and c) the third and fourth azimuthal orientation, respectively, differ by substantially the same increment, and;
wherein the first, second, third and fourth azimuthal orientation are disposed in a helical arrangement and the third o-plate is a positive o-plate.
13. The liquid crystal display of claim 12 , further comprising a fourth c-plate positioned so that the second o-plate is between the fourth o-plate and the liquid crystal cell and the third and fourth c-plate are positve c-plate.