In-Plane Switching Liquid Crystal Display

• US 20180113362A1
• Filed: 10/26/2016
• Published: 04/26/2018
• Est. Priority Date: 10/26/2016
• Status: Active Grant

• Current Assignee: A.U. Vista Inc. (AUO Corp.)
• Original Assignee: A.U. Vista Inc. (AUO Corp.)
• Inventors: LAN, Yi-Fen
• Granted Patent: US 10,180,598 B2
• Time in Patent Office: Days
• CPC Class Codes: G02F 1/133528 Polarisers
• CPC Class Codes: G02F 1/133531 characterised by the arrangement of polariser or analyser axes
• CPC Class Codes: G02F 1/133707 Structures for producing distorted electric fields, e.g. bumps, protrusions, recesses, slits in pixel electrodes
• CPC Class Codes: G02F 1/134363 for applying an electric field parallel to the substrate, i.e. in-plane switching [IPS]
• CPC Class Codes: G02F 1/137 characterised by the electro-optical or magneto-optical effect, e.g. field-induced phase transition, orientation effect, guest-host interaction or dynamic scattering
• CPC Class Codes: G02F 1/13793 Blue phases
• CPC Class Codes: G02F 2201/124 interdigital

Abstract

An in-plane switching liquid crystal display having a plurality of protrude electrodes of a special shape is disclosed. Each of the protrusion electrodes has a protrusion body with a surface coated with an electrically conductive material. The protrusion body has flat side located on the lower substrate of the liquid crystal display, defining the basewidth of the protrusion electrodes. The protrusion body has a top portion with a round head and a bottom portion with a waist portion, smaller than the basewidth. It has been found that, the round head of the top portion and the waist portion of the bottom portion can improve the efficiency of the optical transmissivity of the liquid crystal layer as well the contrast between the bright state and the dark state of the display.

Claims

1. A liquid crystal display comprising:

a first substrate;

a second substrate;

a liquid crystal layer disposed between the first substrate and the second substrate,

a plurality of first protrusion electrodes and a plurality of second protrusion electrodes alternately arranged on the second substrate such that each of the plurality of first protrusion electrodes is adjacent to but spaced from at least one of the plurality of second protrusion electrodes, wherein each of the plurality of first protrusion electrodes and the plurality of second protrusion electrodes comprises a protrusion body, the protrusion body having a cross-sectional area comprising a flat side adjacent to the second substrate, a round side opposing the flat side, and a body section between the flat side and the round side, such that the body section is bound by the round side, the flat side, a first area side and a second area side, the flat side having a basewidth, wherein the first area side and the second area side are separated by a varied distance, the varied distance having a shortest distance defining a waist of the body section, the waist smaller than the basewidth; and

a voltage source electrically coupled to the plurality of first protrusion electrodes and the plurality of second protrusion electrodes, the voltage source arranged to provide a voltage potential between a first protrusion electrode and an adjacent second protrusion electrode, such that

the liquid crystal layer is configured in a first optical state when the voltage potential is provided between the first protrusion electrodes and the second protrusion electrodes, and

the liquid crystal molecules are configured in a second optical second state, when the first protrusion electrodes are electrically coupled to the second protrusion electrodes.

2. The liquid crystal display according to claim 1, wherein the body section comprises a top portion having the round side, and a bottom portion having the flat side, the first area side and the second area side, the bottom portion adjoining the top portion, wherein

the top portion has an arcuate edge and a flat edge adjoining the arcuate edge, the flat edge having a flat edge length, and

the bottom portion is bound by an upper edge, a lower edge, a first side edge and a second side edge, the first side edge defining the first area side, the second side edge defining the second area side, the upper edge parallel to the lower edge, the upper edge having an upper edge length equal to the flat edge length, the lower edge having a lower edge length equal to the basewidth of the flat side, and wherein

the arcuate edge and the flat edge of the top portion define a first angle at a joining point of the arcuate edge and the flat edge, and

the upper edge and the first side edge of the bottom portion define a second angle at a joining point of the upper edge and the first side edge, a sum of the first angle and the second angle having an angle range between 90 and 180 degrees.

3. The liquid crystal display according to claim 2, wherein the bottom portion has a portion height separating the upper edge and the lower edge, and the bottom portion comprises a first trapezoid and a second trapezoid adjoining the first trapezoid, wherein

the first trapezoid is bound by a first side, a second side, a third side and a fourth side, the first side parallel to and separated by a first height from the second side, the first side having a first side length equal to the basewidth, the second side having a second side length equal to the waist of the body section, and

the second trapezoid is bound by a fifth side, a sixth side, a seventh side and an eighth side, the fifth side parallel to and separated by a second height from the sixth side, the fifth side having a fifth side length equal to the second side length of the first trapezoid, the sixth side having a sixth side length equal to the upper edge length of the bottom portion, and wherein

the third side and the seventh side define the first side edge of the bottom portion;

the fourth side and the eighth side define the second side edge of the bottom portion;

the second angle is defined at a joining point of the sixth side and the seventh side of the second trapezoid; and

a sum of the first height and the second height is equal to the portion height, and wherein

the sixth side length is smaller than, equal to, or greater than the first side length, and

the first height is smaller than, equal to, or greater than the second height.

4. The liquid crystal display of claim 2, wherein

the lower edge of the bottom portion comprises a first straight line having a first line length equal to the basewidth;

the upper edge of the bottom portion comprises a second straight line having a second line length equal to the flat edge length of the top portion;

the first side edge of the bottom portion comprises a first curved line;

the second side edge of the bottom portion comprises a second curved line, and wherein a smallest distance between the first side edge and the second side edge is equal to the waist of the body section; and

the second angle of the bottom portion is defined by a joining point of the first curved line and the second straight line.

5. The liquid crystal display of claim 2, wherein

the lower edge of the bottom portion comprises a first straight line having a first line length equal to the basewidth;

the upper edge of the bottom portion comprises a second straight line having a second line length equal to the flat edge of the top portion;

the first side edge of the bottom portion comprises a first curved line and a first straight section adjoining the first straight line at a right angle; and

the second side edge of the bottom portion comprises a second curved line and a second straight section adjoining the first straight line at a right angle, and wherein a smallest distance between the first side edge and the second side edge is equal to the waist of the body section, and the second angle of the bottom portion is defined at a joining point of the first curved line and the second straight line.

6. The liquid crystal display of claim 2, wherein

the lower edge of the bottom portion comprises a first straight line having a first line length equal to the basewidth;

the upper edge of the bottom portion comprises a second straight line having a second line length equal to the flat edge length of the top portion;

the first side edge of the bottom portion comprises a first curved line and a first straight section adjoining the second straight line at a right angle; and

the second side edge of the bottom portion comprises a second curved line and a second straight section adjoining the second straight line at a right angle, and wherein a smallest distance between the first side edge and the second side edge is equal to the waist of the body section, and the second angle of the bottom portion is defined at a joining point of the first straight section and the second straight line.

7. The liquid crystal display according to claim 2, wherein the bottom portion has a portion height separating the upper edge and the lower edge, and the bottom portion comprises a first trapezoid, a rectangle adjoining the first trapezoid, and a second trapezoid adjoining the rectangle, wherein

the first trapezoid is bound by a first side, a second side, a third side and a fourth side, the first side parallel to and separated by a first height from the second side, the first side having a first side length equal to the basewidth, the second side having a second side length equal to the waist of the body section;

the rectangle has a rectangle height and a rectangle width equal to the second side length, the rectangle comprising a first rectangle side and a second rectangle side separated by the rectangular width; and

the second trapezoid is bound by a fifth side, a sixth side, a seventh side and an eighth side, the fifth side parallel to and separated by a second height from the sixth side, the fifth side having a fifth side length equal to the rectangle width, the sixth side having a sixth side length equal to the upper edge length of the bottom portion, and wherein

the third side, the first rectangle side and the seventh side define the first side edge of the bottom portion;

the fourth side, the second rectangle side and the eighth side define the second side edge of the bottom portion;

a sum of the first height, the rectangle height and the second height is equal to the portion height; and

the second angle of the bottom portion is defined at a joining point of the sixth side and the seventh side of the second trapezoid, and wherein

the sixth side length is smaller than, equal to, or greater than the first side length, and

the first height is smaller than, equal to, or greater than the second height.

8. The liquid crystal display according to claim 2, wherein the bottom portion has a portion height separating the upper edge and the lower edge, and the bottom portion comprises a first trapezoid, a second trapezoid adjoining the first trapezoid, a rectangle adjoining the first trapezoid, wherein

the first trapezoid is bound by a first side, a second side, a third side and a fourth side, the first side parallel to and separated by a first height from the second side, the first side having a first side length equal to the basewidth, the second side having a second side length equal to the waist of the body section;

the second trapezoid is bound by a fifth side, a sixth side, a seventh side and an eighth side, the fifth side parallel to and separated by a second height from the sixth side, the fifth side having a fifth side length equal to the second side length, the sixth side having a sixth side length equal to the upper edge length of the bottom portion; and

the rectangle has a rectangle height and a rectangle width equal to the first side length, the rectangle comprising a first rectangle side and a second rectangle side separated by the rectangle width, and wherein

the third side, the first rectangle side and the seventh side define the first side edge of the bottom portion;

the fourth side, the second rectangle side and the eighth side define the second side edge of the bottom portion;

a sum of the first height, the rectangle height and the second height is equal to the portion height, and

the second angle of the bottom portion is defined at a joining point of the sixth side and the seventh side of the second trapezoid, and wherein

the sixth side length is smaller than, equal to, or greater than the first side length, and

the first height is smaller than, equal to, or greater than the second height.

9. The liquid crystal display according to claim 2, wherein the bottom portion has a portion height separating the upper edge and the lower edge, and the bottom portion comprises a first trapezoid, a second trapezoid adjoining the first trapezoid, a rectangle adjoining the second trapezoid, wherein

the first trapezoid is bound by a first side, a second side, a third side and a fourth side, the first side parallel to and separated by a first height from the second side, the first side having a first side length equal to the basewidth, the second side having a second side length equal to the waist of the body section;

the second trapezoid is bound by a fifth side, a sixth side, a seventh side and an eighth side, the fifth side parallel to and separated by a second height from the sixth side, the fifth side having a fifth side length equal to the second side length, the sixth side having a sixth side length equal to the upper edge length of the bottom portion; and

the rectangle has a rectangle height and a rectangle width equal to the second side length, the rectangle comprising a first rectangle side and a second rectangle side separated by the rectangle width, an upper rectangle edge and a lower rectangle edge separated by the rectangle height, and wherein

the third side, the first rectangle side and the seventh side define the first side edge of the bottom portion,

the fourth side, the second rectangle side and the eighth side define the second side edge of the bottom portion,

a sum of the first height, the rectangle height and the second height is equal to the portion height and

the second angle of the bottom portion is defined at a joining point of first rectangle side and the upper rectangle edge, and wherein

the sixth side length is smaller than, equal to, or greater than the first side length, and

the first height is smaller than, equal to, or greater than the second height.

10. The liquid crystal display according to claim 2, wherein the body section further comprises an extended portion location between the lower edge of the bottom portion and the second substrate, wherein the extended portion has an extended upper edge and an extended lower edge parallel to the extended upper edge, the extended upper edge having a length equal to the lower edge length of the bottom portion, the extended lower edge having a length smaller than, equal to, or greater than the lower edge length.

11. The liquid crystal display according to claim 3, wherein the bottom portion further comprises a rectangle located between the second side of the first trapezoid and the fifth side of the second trapezoid, the rectangle having a width equal to the second side length.

12. The liquid crystal display according to claim 2, wherein the arcuate edge of the top portion is a section of a circle defined by a radius of curvature, the arcuate edge having a first length and the flat edge of the top portion having a second length, and wherein

a ratio of the first length to the radius of curvature is greater than 0 but smaller than or equal to 2π

, and

a ratio of the second length to the radius of curvature is greater than 0 but smaller than or equal to 2.

13. The liquid crystal display according to claim 2, wherein the arcuate edge of the top portion is a section of a parabolic arc.

14. The liquid crystal display according to claim 1, wherein the protrusion body has a surface and an electrically conductive layer provided on at least part of the surface, and wherein the voltage source is electrically coupled to the electrically conductive layer to provide the voltage potential.

15. The liquid crystal display according to claim 1, wherein the plurality of first protrusion electrodes and the plurality of second protrusion electrodes are made of an electrically conductive material.

20. The liquid crystal display according to claim 1, wherein the elongated body is made of an electrically conductive material.

16. A liquid crystal display comprising:

a first substrate;

a second substrate;

a liquid crystal layer disposed between the first substrate and the second substrate,

a plurality of first protrusion electrodes and a plurality of second protrusion electrodes alternately arranged on the second substrate such that each of the plurality of first protrusion electrodes is adjacent to but spaced from at least one of the plurality of second protrusion electrodes, wherein each of the plurality of first protrusion electrodes and each of the plurality of second protrusion electrodes have an elongated body, the elongated body having a round top, a flat bottom contacting the second substrate, and a waist located between the round top and a flat bottom, the flat bottom having a width and a length, wherein the waist is smaller than the width; and

a voltage source electrically coupled to the plurality of first protrusion electrodes and the plurality of second protrusion electrodes, the voltage source arranged to provide a voltage potential between a first protrusion electrode and an adjacent second protrusion electrode, such that

the liquid crystal layer is configured in a first optical state when the voltage potential is provided between the first protrusion electrodes and the second protrusion electrodes, and

the liquid crystal molecules are configured in a second optical second state, when the first protrusion electrodes are electrically coupled to the second protrusion electrodes.

17. The liquid crystal display according to claim 16, wherein the round top comprises an elongated curved edge and the elongated body comprises a protrusion body with a varied width located between the elongated curved edge and the flat bottom, the varied width having a smaller width defining the waist.

18. The liquid crystal display according to claim 17, wherein the protrusion body comprises a first end joining the elongated curved edge at a joining line and a second end joining the flat bottom, and wherein the first end of the protrusion body and the elongated curved edge define an angle at the joining line, the angle having an angle range between 90 and 180 degrees.

19. The liquid crystal display according to claim 16, wherein the elongated body has a surface and an electrically conductive layer provided on at least part of the surface, and wherein the voltage source is electrically coupled to the electrically conductive layer to provide the voltage potential.