Liquid crystal display device

Patent metadata

Field	Value
Publication number	US-10317746-B2
Application number	US-201715483108-A
Country	US
Kind code	B2
Filing date	Apr 10, 2017
Priority date	Aug 10, 2016
Publication date	Jun 11, 2019
Grant date	Jun 11, 2019

Abstract

A liquid crystal display device includes a pixel electrode having a stem electrode in a first direction and a plurality of branch electrode extending from the stem electrode. An angle between the stem electrode and each of the branch electrode increases as the branch electrodes approach a center of the stem electrode and the angle decreases as the branch electrodes approach an end of the stem electrode.

First claim

What is claimed is:

1. A liquid crystal display device, comprising:
a substrate; and
a pixel electrode on the substrate and including:
a stem electrode extending along a first direction, outermost ends of the stem electrode being spaced apart from each other along the first direction, and a center of the stem electrode being a center point between the outermost ends of the stem electrode, and
a plurality of branch electrodes extending from the stem electrode, at least some of the plurality of branch electrodes having first ends connected to the stem electrode and second ends, opposite the first ends, wherein the at least some of the plurality of branch electrodes are inclined toward the center of the stem electrode to define angles between the first ends and the stem electrode,
wherein the plurality of branch electrodes extends such that the angles between the first ends and the stem electrode increase as the plurality of branch electrodes approaches the center of the stem electrode.

2. The liquid crystal display device as claimed in claim 1 , wherein:
all the plurality of branch electrodes are directly connected to the stem electrode, and
a first branch electrode of the plurality of branch electrodes is closest to the center of the stem electrode, the first branch electrode extending in a second direction crossing the first direction.

3. The liquid crystal display device as claimed in claim 2 , wherein:
all the plurality of branch electrodes, except the first branch electrode, are inclined toward the center of the stem electrode to have the angles between the first ends and the stem electrode, and
a minimum angle between the stem electrode and each of the inclining branch electrodes is 0° to 15° and a maximum angle therebetween is 35° to 45°.

4. The liquid crystal display device as claimed in claim 1 , wherein:
the pixel electrode includes a connection electrode connected to and extending from a branch electrode of the plurality of branch electrodes that is closest to the center of the stem electrode, the connection electrode extending in the first direction, and
the connection electrode connects second ends of only some of the plurality of branch electrodes to each other.

5. The liquid crystal display device as claimed in claim 1 , wherein:
the pixel electrode includes a plurality of first edge electrodes and a plurality of second edge electrodes,
the first edge electrodes are connected with the outermost ends of the stem electrode, respectively, the first edge electrodes extending along edges of the pixel electrode in a second direction crossing the first direction, and
the second edge electrodes are connected with different ends of the first edge electrodes and extend along edges of the pixel electrode in the first direction.

6. The liquid crystal display device as claimed in claim 5 , further comprising:
an insulation film between the substrate and the pixel electrode,
wherein the insulation film includes a first portion having an upper surface that is substantially flat and a second portion protruding in a direction crossing the upper surface of the first portion and partially overlapping the first edge electrodes.

7. The liquid crystal display device as claimed in claim 6 , further comprising:
a gate line and a data line between the substrate and the insulation film and insulated from each other, wherein the gate line extends in a second direction crossing the first direction, and wherein the data line extends in the first direction.

8. The liquid crystal display device as claimed in claim 6 , wherein the second portion is on an extension line of the stem electrode.

9. The liquid crystal display device as claimed in claim 6 , wherein a cross-section of the second portion of the insulation film along the first direction has a trapezoidal shape having an upper surface that is substantially flat, and a top view of the second portion of the insulation film has a rectangular shape.

10. The liquid crystal display device as claimed in claim 9 , wherein:
in the cross-section of the second portion of the insulation film along the first direction, a length of a bottom side is 4 μm to 6 μm, a height is 1 μm to 2 μm, and an angle between a lateral side and the bottom side is 40° to 80°.

11. The liquid crystal display device as claimed in claim 1 , wherein:
the pixel electrode is divided into first to fourth quadrants having a same shape, the first quadrant defining a first domain at a right upper end, the second quadrant defining a second domain at a left upper end, the third quadrant defining a third domain at a left lower end, and the fourth quadrant defining a fourth domain at a right lower end, and
first branch electrodes of the plurality of branch electrodes in the first domain extend toward the right lower end, second branch electrodes of the plurality of branch electrodes in the second domain extend toward the left lower end, third branch electrodes of the plurality of branch electrodes in the third domain extend toward the left upper end, and fourth branch electrodes of the plurality of branch electrodes in the fourth domain extend toward the right upper end.

12. The liquid crystal display device as claimed in claim 11 , wherein:
the pixel electrode includes a connection electrode connecting second ends of some of the plurality of branch electrodes to each other, and
the connection electrode extends upward from a branch electrode of the first branch electrodes at a lowermost end of the first domain, extends upward from a branch electrode of the second branch electrodes at a lowermost end of the second domain, extends downward from a branch electrode of the third branch electrodes at an uppermost end of the third domain, and extends downward from a branch electrode of the fourth branch electrodes at an uppermost end of the fourth domain.

13. The liquid crystal display device as claimed in claim 11 , wherein a number of branch electrodes of the plurality of branch electrodes connected by the connection electrode in each of the first to fourth domains is 75% or less than a total number of branch electrodes of the plurality of branch electrodes in each of the first to fourth domains.

14. A liquid crystal display device, comprising:
a substrate; and
a pixel electrode on the substrate and including:
a stem electrode extending along a first direction, and
a plurality of branch electrodes extending from the stem electrode,
wherein a branch electrode of the plurality of branch electrodes closest to a center of the stem electrode in the first direction extends in a second direction crossing the first direction,
wherein two adjacent branch electrodes of the plurality of branch electrodes are spaced apart from each other by a first length at a point at which the two adjacent branch electrodes contact the stem electrode,
wherein the two adjacent branch electrodes are spaced apart by a second length at distal ends thereof, and
wherein the first length is greater than the second length.

15. The liquid crystal display device as claimed in claim 14 , wherein:
a distance between the two adjacent branch electrodes spaced apart from each other along the first direction increases approaching the stem electrode and decreases approaching the distal ends of the branch electrodes.

16. The liquid crystal display device as claimed in claim 14 , wherein:
the pixel electrode includes a connection electrode connecting distal ends of only some of the branch electrodes to each other, the connection electrode extending in the first direction, and
the connection electrode extends

Assignees

• Samsung Display Co Ltd

Inventors

• Lazo Israel Esteban
• Park Heung Shik
• Shin Ki Chul

Classifications

• G02F1/134336

  Matrix · CPC title

• G02F2001/13629

  Physics · mapped topic

• G02F1/134309 Primary

  characterised by their geometrical arrangement · CPC title

• G02F2001/133776

  Physics · mapped topic

• G02F1/133707

  Structures for producing distorted electric fields, e.g. bumps, protrusions, recesses, slits in pixel electrodes · CPC title