Liquid crystal display device

Abstract

The liquid crystal display device includes a first substrate, a second substrate, and a liquid crystal layer between the first substrate and the second substrat. The first substrate includes a transistor including an oxide semiconductor film including a channel formation region; a pixel electrode electrically connected to the transistor; an insulating layer in contact with the pixel electrode; and a first common electrode in contact with the insulating layer. The second substrate faces the first substrate and includes a second common electrode. A negative liquid crystal material is used for the liquid crystal layer. The specific resistivity of the liquid crystal material is greater than or equal to 1.0×10 13 Ω·cm and less than or equal to 1.0×10 16 Ω·cm.

What is claimed is: 
     
         1 . A liquid crystal display device comprising:
 a first substrate comprising:
 a transistor; 
 a first electrode electrically connected to one of a source electrode and a drain electrode of the transistor; 
 an insulating layer in contact with the first electrode; 
 a second electrode in contact with the insulating layer; and 
 a capacitor line electrically connected to the second electrode, 
   a second substrate facing the first substrate, the second substrate comprising a third electrode; and   a liquid crystal layer comprising a liquid crystal material between the first substrate and the second substrate,   wherein a potential difference between the second electrode and the third electrode is smaller than a potential difference between the third electrode and the first electrode, and   wherein the potential difference between the third electrode and the first electrode is smaller than a potential difference between the second electrode and the first electrode.   
     
     
         2 . The liquid crystal display device according to  claim 1 , wherein the second electrode is in contact with the capacitor line. 
     
     
         3 . The liquid crystal display device according to  claim 1 , further comprising a planarization film between the first substrate and the first electrode. 
     
     
         4 . The liquid crystal display device according to  claim 1 , further comprising a color film between the second substrate and the third electrode. 
     
     
         5 . A liquid crystal display device comprising:
 a first substrate comprising:
 a transistor; 
 a first electrode electrically connected to one of a source electrode and a drain electrode of the transistor; 
 an insulating layer in contact with the first electrode; 
 a second electrode in contact with the insulating layer; and 
 a capacitor line electrically connected to the second electrode, 
   a second substrate facing the first substrate, the second substrate comprising a third electrode; and   a liquid crystal layer between the first substrate and the second substrate,   wherein a potential difference between the second electrode and the third electrode is smaller than a potential difference between the third electrode and the first electrode,   wherein the potential difference between the third electrode and the first electrode is smaller than a potential difference between the second electrode and the first electrode, and   wherein the liquid crystal layer comprises a liquid crystal material with negative dielectric anisotropy   
     
     
         6 . The liquid crystal display device according to  claim 5 , wherein the second electrode is in contact with the capacitor line. 
     
     
         7 . The liquid crystal display device according to  claim 5 , wherein a dielectric constant anisotropy of the liquid crystal material with negative dielectric anisotropy is −3.0. 
     
     
         8 . The liquid crystal display device according to  claim 5 , further comprising a planarization film between the first substrate and the first electrode. 
     
     
         9 . The liquid crystal display device according to  claim 5 , further comprising a color film between the second substrate and the third electrode. 
     
     
         10 . The liquid crystal display device according to  claim 5 , wherein the second electrode and the third electrode are connected to different power supply lines. 
     
     
         11 . A liquid crystal display device comprising:
 a first substrate comprising:
 a transistor; 
 a first electrode electrically connected to one of a source electrode and a drain electrode of the transistor; 
 an insulating layer; 
 a second electrode in contact with the insulating layer; and 
 a capacitor line electrically connected to the second electrode, 
   a second substrate facing the first substrate, the second substrate comprising a third electrode; and   a liquid crystal layer comprising a liquid crystal material between the first substrate and the second substrate,   wherein the second electrode has a region overlapping with the first electrode with the insulating layer provided therebetween,   wherein a potential difference between the second electrode and the third electrode is smaller than a potential difference between the third electrode and the first electrode, and   wherein the potential difference between the third electrode and the first electrode is smaller than a potential difference between the second electrode and the first electrode.   
     
     
         12 . The liquid crystal display device according to  claim 11 , wherein the second electrode is in contact with the capacitor line. 
     
     
         13 . The liquid crystal display device according to  claim 11 , further comprising a planarization film between the first substrate and the first electrode. 
     
     
         14 . The liquid crystal display device according to  claim 11 , further comprising a color film between the second substrate and the third electrode.