Liquid crystal display having wide viewing angle

Abstract

A tetragonal ring shape aperture is formed in the common electrode on one substrate and a cross shape aperture is formed at the position corresponding to the center of the tetragonal ring shape aperture in the pixel electrode on the other substrate. A liquid crystal layer between two electrodes are divided to four domains where the directors of the liquid crystal layer have different angles when a voltage is applied to the electrodes. The directors in adjacent domains make a right angle. The tetragonal ring shape aperture is broken at midpoint of each side of the tetragon, and the width of the aperture to decreases as goes from the bent point to the edge. Wide viewing angle is obtained by four domains where the directors of the liquid crystal layer indicate different directions, disclination is removed and luminance increases.

What is claimed is: 
     
         1 . A liquid crystal display comprising:
 a first substrate having an inner surface and an outer surface;   a first electrode on the inner surface of the first substrate;   a second substrate opposite the first substrate and having an inner surface and an outer surface; and   a second electrode on the inner surface of the second substrate and located at a position corresponding to the first electrode,   wherein the first electrode and the second electrode have a plurality of to first and second apertures, respectively, and the first and the second apertures form a substantially closed area.   
     
     
         2 . The liquid crystal display of  claim 1 , wherein boundaries of the first and the second apertures are linear, curved or bent with an obtuse angle. 
     
     
         3 . The liquid crystal display of  claim 2 , wherein the first and the second apertures forming the substantially closed area are arranged symmetrically. 
     
     
         4 . The liquid crystal display of  claim 3 , wherein the width of the first and the second apertures becomes larger form ends to centers of the first and the second apertures. 
     
     
         5 . The liquid crystal display of  claim 3 , wherein width of the first and the second apertures is 3-20 μm. 
     
     
         6 . The liquid crystal display of  claim 3 , wherein distance between the first and the second apertures is 5-20 μm. 
     
     
         7 . The liquid crystal display of  claim 3 , further comprising:
 a liquid crystal layer interposed between the first and the second substrates and having negative dielectric anisotropy;   a first and a second alignment layers on the first and the second electrodes respectively, the first and the second alignment layers aligning the long axes of liquid crystal molecules in the liquid crystal layer to be perpendicular to the first and the second substrates; and   a first and a second polarizers on the outer surfaces of the first and the second substrates, respectively.   
     
     
         8 . The liquid crystal display of  claim 7 , wherein the polarizing directions of the polarizers are perpendicular to each other. 
     
     
         9 . The liquid crystal display of  claim 8 , wherein the number of average axial directions of domains defined by the first and the second apertures is four. 
     
     
         10 . The liquid crystal display of  claim 9 , wherein the average axial directions make 45°±10° with the polarizing directions of the first and the is second polarizers. 
     
     
         11 . The liquid crystal display of  claim 10 , wherein the average axial directions of adjacent domains makes substantially right angle. 
     
     
         12 . The liquid crystal display comprising:
 a first substrate having an inner surface and an outer surface;   a first electrode on the inner surface of the first substrate;   a second substrate opposite the first substrate and having an inner surface and an outer surface; and   a second electrode on the inner surface of the second substrate and located at a position corresponding to the first electrode,   wherein the first electrode and the second electrode have a plurality of first and second apertures, respectively, and, boundaries of the first and the second apertures are linear, curved or bent with an obtuse angle.   
     
     
         13 . A liquid crystal display comprising:
 a first substrate having an inner surface and an outer surface;   a first electrode on the inner surface of the first substrate;   a second substrate opposite the first substrate and having an inner surface and an outer surface; and   a second electrode on the inner surface of the second substrate and to located at a position corresponding to the first electrode,   wherein the first electrode and the second electrode have a plurality of first and second apertures, respectively, and the width the first and the second apertures becomes larger form ends to centers of the first and the second apertures.   
     
     
         14 . The liquid crystal display of  claim 13 , wherein the first and the second apertures form a substantially closed area. 
     
     
         15 . The liquid crystal display of  claim 14 , wherein the first and the second apertures forming the substantially closed area are arranged symmetrically. 
     
     
         16 . The liquid crystal display of  claim 15 , wherein width of the first and the second apertures is 3-20 m. 
     
     
         17 . The liquid crystal display of  claim 15 , wherein distance between the first and the second apertures is 5-20 μm. 
     
     
         18 . The liquid crystal display of  claim 15 , further comprising:
 a liquid crystal layer interposed between the first and the second substrates and having negative dielectric anisotropy;   a first and a second alignment layers on the first and the second electrodes respectively, the first and the second alignment layers aligning the long axes of liquid crystal molecules in the liquid crystal layer to be perpendicular to the first and the second substrates; and   a first and a second polarizers on the outer surfaces of the first and the second substrates, respectively.   
     
     
         19 . The liquid crystal display of  claim 18 , wherein the polarizing directions of the polarizers are perpendicular to each other. 
     
     
         20 . The liquid crystal display of  claim 19 , wherein the number of average axial directions of domains defined by the first and the second apertures is four. 
     
     
         21 . The liquid crystal display of  claim 20 , wherein the average axial directions make 45°±10° with the polarizing directions of the first and the second polarizers. 
     
     
         22 . The liquid crystal display of  claim 21 , wherein the average axial directions of adjacent domains makes substantially right angle.