Liquid crystal display device

Abstract

The displacement between a TFT substrate and a counter substrate and the cut of an alignment film caused by a columnar spacer are prevented. A liquid crystal display device includes: a TFT substrate including a scanning line extending in a first direction, a picture signal line extending in a second direction, a pixel electrode formed in a region surrounded by the scanning line and the picture signal line, and a common electrode formed as opposed to the pixel electrode through an insulating film; a counter substrate disposed as opposed to the TFT substrate and having a spacer; and a liquid crystal sandwiched between the substrates. A common metal interconnection is formed to cover the picture signal line or the scanning line, and stacked on the common electrode. A through hole is formed on the common metal interconnection. The tip end of the spacer is disposed inside the through hole.

What is claimed is: 
     
         1 . A liquid crystal display device comprising:
 a TFT substrate including
 a scanning line, 
 a signal line, 
 a pixel electrode, 
 a common electrode, and 
 an insulating film between the pixel electrode and the common electrode; 
   a counter substrate including a spacer; and   a liquid crystal between the TFT substrate and the counter substrate, wherein   
       a common metal is between the liquid crystal and the signal line or the scanning line, the common metal is stacked on the common electrode;
 the common metal includes a through hole; and 
 the spacer is inside the through hole in plan view. 
 
     
     
         2 . The liquid crystal display device according to  claim 1 ,
 wherein an opening is provided on a part of the through hole, and the through hole is opened to an outer side of the common metal.   
     
     
         3 . The liquid crystal display device according to  claim 2 ,
 wherein the common electrode is transparent.   
     
     
         4 . The liquid crystal display device according to  claim 1 ,
 wherein the common metal is formed on an upper side of the common electrode.   
     
     
         5 . The liquid crystal display device according to  claim 1 ,
 wherein the pixels exhibiting different colors to one another are arrayed in a first direction, and   wherein a width of the common metal on a boundary of the pixel in the first direction is different from a width of the common metal on an adjacent boundary in the first direction.   
     
     
         6 . The liquid crystal display device according to  claim 1 ,
 wherein: the pixels exhibiting different colors to one another are arrayed in the first direction; and   the common metal on a boundary of the pixel in the first direction has a left width different from a right width based on a center of the picture signal line on the boundary.   
     
     
         7 . The liquid crystal display device according to  claim 1 , wherein a through hole is formed on the insulating film, the through hole being laid on the through hole of the common metal. 
     
     
         8 . The liquid crystal display device according to any one of  claims 1  to  7 ,
 wherein the common electrode is formed on an upper side of the pixel electrode. 
 
     
     
         9 . The liquid crystal display device according to  claim 1 ,
 wherein the common metal has a three-layer structure.   
     
     
         10 . The liquid crystal display device according to  claim 1 ,
 wherein the common metal has a two-layer structure.   
     
     
         11 . A liquid crystal display device comprising:
 a TFT substrate including
 a scanning line extending in a first direction, 
 a signal line extending in a second direction, 
 a pixel electrode, and 
 a common electrode formed as opposed to the pixel electrode through a first insulating film; 
   a counter substrate disposed as opposed to the TFT substrate, the counter substrate including a spacer; and   a liquid crystal between the TFT substrate and the counter substrate, wherein   the pixel electrode, the first insulating film, and the common electrode are formed on a second insulating film;   a contact hole for connecting the pixel electrode to a TFT is formed on the second insulating film;   a common metal is formed to cover the signal line or the scanning line, the common metal being stacked on the common electrode;   a through hole is formed on the common metal;   the spacer is disposed inside the through hole; and   near a region in which the contact hole is formed, the common metal covering the signal line is formed on every other signal line in the first direction.   
     
     
         12 . The liquid crystal display device according to  claim 11 ,
 wherein near a region in which the contact hole is formed in the first direction, a center of the contact hole is disposed in a direction apart from a region in which the signal line is formed, with respect to a center of the pixel.   
     
     
         13 . A liquid crystal display device comprising:
 a TET substrate including
 a scanning line extending in a first direction, 
 a signal line extending in a second direction, 
 a pixel electrode, and 
 a common electrode formed as opposed to the pixel electrode through an insulating film; 
   a counter substrate including a spacer; and   a liquid crystal between the TFT substrate and the counter substrate, wherein   an extending direction of the signal line forms a predetermined angle with an initial alignment direction of liquid crystal molecules;   a common metal is formed to cover the signal line, the common metal being stacked on the common electrode;   a width of the common electrode is wider than a width of the signal line; and   a thickness of the signal line is greater than a thickness of the common electrode.   
     
     
         14 . The liquid crystal display device according to  claim 13 ,
 wherein the predetermined angle ranges from an angle of five to 15 degrees.   
     
     
         15 . The liquid crystal display device according to  claim 13 ,
 wherein: an insulating film is present between the signal line and the common metal in cross sectional view; and   x≧y tan 5° is held, where a thickness of the insulating film is defined as y, a width of the common metal is defined as w1, the width of the signal line is defined as w2, and a distance x=(w1−w2)/2.   
     
     
         16 . The liquid crystal display device according to  claim 15 ,
 wherein the distance x is 3 μm or less.   
     
     
         17 . The liquid crystal display device according to  claim 13 ,
 wherein the common metal has a three-layer structure.   
     
     
         18 . The liquid crystal display device according to  claim 13 ,
 wherein the common metal has a two-layer structure.