Liquid crystal display

Abstract

A liquid crystal display includes a first insulating substrate, thin transistors formed on the first insulating substrate, and pixel electrodes connected to the thin film transistors each with an opening pattern. A second insulating substrate faces the first insulating substrate. A black matrix and color filters are formed on the second insulating substrate, and a common electrode covers the black matrix and the color filters. A protrusion pattern is formed on the common electrode. The protrusion pattern is pillar-shaped with top and bottom sides. The top and bottom sides of the protrusion pattern are shaped with a circle, a rectangle, or a rectangle with curved edges. The protrusion pattern includes a protrusion having a relatively small thickness, and a protrusion having a relatively large thickness. The former protrusion is used for domain partitioning, and the latter protrusion is used as a spacer. A vertical alignment layer is internally formed on the substrates, and a liquid crystal is injected in-between the substrates. Polarizing plates are externally attached to the substrates, respectively. A bi-axial film and a λ/4 plate are interposed between the respective substrates and the respective polarizing plates. The bi-axial film and the λ/4 plate transform the linear-polarizing into a circular-polarizing.

1 . A liquid crystal display, comprising:
 a first insulating substrate;   a second insulating substrate facing the first insulating substrate;   a liquid crystal layer sandwiched between the first and the second insulating substrates;   a first polarizing plate and a second polarizing plate externally attached to the first insulating substrate and the second insulating substrate;   a first bi-axial film interposed between the first insulating substrate and the first polarizing plate; and   a second bi-axial film interposed between the second insulating substrate and the second polarizing plate,   wherein a polarizing axis of the first polarizing plate is perpendicular to a polarizing axis of the second polarizing plate,   a longest axis of the first bi-axial film is perpendicular to a longest axis of the second bi-axial film, and   the polarizing axes of the first and the second polarizing plates are angled with respect to the longest axes of the first and the second bi-axial films by 45 degree.   
   
   
       2 . The liquid crystal display of  claim 1 , wherein the Rx of the first and second bi-axial films is in the range of 100-150 nm and the Rz of the first and second bi-axial films is in the range of 80-180 nm. 
   
   
       3 . The liquid crystal display of  claim 1 , further comprising:
 pixel electrodes formed on the first insulating substrate each with a plurality of opening patterns, the pixel electrodes being partitioned into a plurality of micro-regions by way of the opening patterns;   a thin film transistor formed on the first insulating substrate while being electrically connected to the pixel electrode;   a common electrode formed on the second insulating substrate; and   a plurality of domain divider formed on the common electrode, the plurality of domain divider being placed at the micro-regions of the pixel electrode to regulate the inclining directions of liquid crystal molecules in the liquid crystal layer.   
   
   
       4 . The liquid crystal display of  claim 3 , further comprising a black matrix interposed between the second insulating substrate and the common electrode while being patterned. 
   
   
       5 . The liquid crystal display of  claim 3 , further comprising color filters interposed between the second insulating substrate and the common electrode corresponding to the pixel electrodes. 
   
   
       6 . The liquid crystal display of  claim 3 , wherein the plurality of domain divider are protrusion patterns. 
   
   
       7 . The liquid crystal display of  claim 6 , wherein the protrusion pattern is shaped of a pillar, a top side and a bottom side of which have a shape of a circle, a rectangle, or a rectangle with curved edges. 
   
   
       8 . The liquid crystal display of  claim 6 , wherein the protrusion pattern has a height of 3.0-4.5 μm. 
   
   
       9 . The liquid crystal display of  claim 6 , wherein the retardation value of the liquid crystal layer is in the range of 0.25-0.4 μm. 
   
   
       10 . The liquid crystal display of  claim 1 , wherein the light incident upon the liquid crystal layer is circularly polarized. 
   
   
       11 . The liquid crystal display of  claim 1 , further comprising a mono-axial film interposed either between the first polarizing plate and the first bi-axial film, or between the second polarizing plate and the second bi-axial film. 
   
   
       12 . The liquid crystal display of  claim 11 , wherein retardation value of the mono-axial film is in the range of 100-300 nm. 
   
   
       13 . The liquid crystal display of  claim 11 , wherein the long axis of the mono-axial film is parallel to the polarizing axis of the neighboring polarizing plate. 
   
   
       14 . The liquid crystal display of  claim 6 , wherein the gap between the first insulating substrate and the second insulating substrate is constantly maintained by the protrusion patterns. 
   
   
       15 . The liquid crystal display of  claim 3 , wherein the plurality of domain divider are located on a central area between the opening patterns. 
   
   
       16 . A liquid crystal display, comprising:
 a first insulating substrate;   a second insulating substrate facing the first insulating substrate;   a liquid crystal layer sandwiched between the first and the second insulating substrates;   a first polarizing plate and a second polarizing plate externally attached to the first insulating substrate and the second insulating substrate;   a first bi-axial film interposed between the first insulating substrate and the first polarizing plate;   a second bi-axial film interposed between the second insulating substrate and the second polarizing plate;   a first λ/4 plate interposed between the first insulating substrate and the first bi-axial film; and   a second λ/4 plate interposed between the second insulating substrate and the second bi-axial film,   wherein a polarizing axis of the first polarizing plate is perpendicular to a polarizing axis of the second polarizing plate,   the polarizing axes of the first and the second polarizing plates are parallel to a longest axes of the first and the second bi-axial films,   slow axes of the first λ/4 plate and the second λ/4 plate are perpendicular to each other, and   the polarizing axes of the first and the second polarizing plates are angled with respect to the slow axes of the first and the second λ/4 plate by 45 degree.   
   
   
       17 . The liquid crystal display of  claim 16 , wherein the Rx of the first and second bi-axial films is in the range of 100-150 nm and the Rz of the first and second bi-axial films is in the range of 80-180 nm. 
   
   
       18 . The liquid crystal display of  claim 16 , further comprising:
 pixel electrodes formed on the first insulating substrate each with a plurality of opening patterns, the pixel electrodes being partitioned into a plurality of micro-regions by way of the opening patterns;   a thin film transistor formed on the first insulating substrate while being electrically connected to the pixel electrode;   a common electrode formed on the second insulating substrate; and   a plurality of domain divider formed on the common electrode, the plurality of domain divider being placed at the micro-regions of the pixel electrode to regulate the inclining directions of liquid crystal molecules in the liquid crystal layer.   
   
   
       19 . The liquid crystal display of  claim 18 , further comprising a black matrix interposed between the second insulating substrate and the common electrode while being patterned. 
   
   
       20 . The liquid crystal display of  claim 18 , further comprising color filters interposed between the second insulating substrate and the common electrode corresponding to the pixel electrodes. 
   
   
       21 . The liquid crystal display of  claim 18 , wherein the plurality of domain divider are protrusion patterns. 
   
   
       22 . The liquid crystal display of  claim 21 , wherein the protrusion pattern is shaped of a pillar, a top side and a bottom side of which have a shape of a circle, a rectangle, or a rectangle with curved edges. 
   
   
       23 . The liquid crystal display of  claim 21 , wherein the protrusion pattern has a height of 3.0-4.5 μm. 
   
   
       24 . The liquid crystal display of  claim 21 , wherein the retardation value of the liquid crystal layer is in the range of 0.25-0.4 μm. 
   
   
       25 . The liquid crystal display of  claim 16 , wherein the light incident upon the liquid crystal layer is circularly polarized. 
   
   
       26 . The liquid crystal display of  claim 16 , further comprising a mono-axial film interposed either between the first polarizing plate and the first bi-axial film, or between the second polarizing plate and the second bi-axial film. 
   
   
       27 . The liquid crystal display of  claim 26 , wherein retardation value of the mono-axial film is in the range of 100-300 nm. 
   
   
       28 . The liquid crystal display of  claim 26 , wherein the long axis of the mono-axial film is parallel to the polarizing axis of the neighboring polarizing plate. 
   
   
       29 . The liquid crystal display of  claim 21 , wherein the gap between the first insulating substrate and the second insulating substrate is constantly maintained by the protrusion patterns. 
   
   
       30 . The liquid crystal display of  claim 18 , wherein the plurality of domain divider are located on a central area between the opening patterns.