Display device and driving method thereof

Abstract

An array substrate ( 10 ) is provided with a pixel electrode ( 3 ) disposed in a region defined by two adjacent gate wirings ( 1 ) and two adjacent source wirings ( 2 ), a switching element ( 5 ) for switching a voltage applied to the pixel electrode ( 3 ) from the source wiring ( 2 ) based on a signal voltage supplied from the gate wiring ( 1 ), a common wiring ( 8 ) arranged between the two adjacent gate wirings ( 1 ) and a common electrode ( 4 ) being electrically connected to the common wiring ( 8 ) and generating an electric field between the pixel electrode ( 3 ) whereto a voltage is applied, wherein the pixel electrode ( 1 ) comprises a first pixel electrode ( 1 a ) and a second pixel electrode ( 2 a ), and the opposing electrode ( 2 ) comprises a first opposing electrode ( 1 b ) and a second opposing electrode ( 2 b ), wherein a first region generates an electric field between the first pixel electrode ( 1 a ) and the first opposing electrode ( 2 a ) whose light transmittance is lower than that of the first pixel electrode ( 1 a ) and a second region generates an electric field between the second pixel electrode ( 1 b ) and the second opposing electrode ( 2 b ) whose light transmittance is higher than that of the second pixel electrode ( 1 b ) are formed.

1 . A display device comprising:
 an array substrate;   an opposing substrate facing the array substrate; and   an electro-optic substance held between the array substrate and the opposing substrate, wherein the array substrate is provided with:   a plurality of gate wirings and a plurality of source wirings intersecting each other;   a pixel electrode disposed in each region defined by two adjacent gate wirings and two adjacent source wirings;   a switching element for switching a voltage applied to the pixel electrode from the source wiring based on a signal voltage supplied from the gate wiring;   a common wiring formed between the two adjacent gate wirings; and   an opposing electrode being electrically connected to the common wiring and generating an electric field for driving the electro-optic substance between the opposing electrode and the pixel electrode whereto a voltage is applied,   wherein the pixel electrode comprises a first pixel electrode and a second pixel electrode, and the opposing electrode comprises a first opposing electrode and a second opposing electrode,   wherein a first region is formed in which an electric field is generated between the first pixel electrode and the first opposing electrode whose light transmittance is lower than that of the first pixel electrode,   wherein a second region is formed in which an electric field is generated between the second pixel electrode and the second opposing electrode whose light transmittance is higher than that of the second pixel electrode.   
   
   
       2 . The display device according to  claim 1 , wherein the first region and the second region are adjacent to each other. 
   
   
       3 . The display device according to  claim 1 , wherein a voltage is supplied to the first pixel electrode and the second pixel electrode from the same source wiring based on a signal voltage fed from the same gate wiring. 
   
   
       4 . The display device according to  claim 3 , wherein the first region and the second region are formed in a single dot. 
   
   
       5 . The display device according to  claim 4 , wherein the interface between the first region and the second region is located on the common wiring, and the first pixel electrode is connected to the second pixel electrode and the first opposing electrode is connected to the second opposing electrode through contact holes formed in insulating layers held in between. 
   
   
       6 . The display device according to  claim 4 , wherein the source wiring is disposed between the first region and the second region, and the switching elements are arranged so as to correspond to the first pixel electrode and the second pixel electrode, respectively. 
   
   
       7 . The display device according to  claim 4 , wherein a plurality of the first regions and a plurality of the second regions are formed and alternately arranged along the gate wiring in such a manner that groups of two consecutively identical regions are alternately disposed, and the interface between that groups of two adjacent first regions and two adjacent second regions exists on the pixel electrode or the opposing electrode. 
   
   
       8 . The display device according to  claim 1 , wherein a plurality of the first regions and a plurality of the second regions are formed and arranged in a manner such that the flicker polarity cyclically changes along both the gate wiring and the source wiring based on the prescribed voltage polarity applied to the first pixel electrode and the second pixel electrode. 
   
   
       9 . The display device according to  claim 8 , wherein the flicker polarities are inverted at every dot along both the gate wiring and the source wiring. 
   
   
       10 . The display device according to  claim 8 , wherein the flicker polarities are inverted at every plurality of dots along both the gate wiring and the source wiring. 
   
   
       11 . The display device according to  claim 1 , wherein the first region and the second region each corresponds to a dot. 
   
   
       12 . The display device according to  claim 1 , wherein the first region and the second region each corresponds to a pixel composed of three dots of red, green and blue. 
   
   
       13 . The display device according to  claim 1 , further comprising storage capacitor electrodes electrically connected to the first pixel electrode and the second pixel electrode, each of the storage capacitor electrodes is arranged in the first region and the second region,
 wherein the two storage capacitor electrodes are located on the common electrode or the gate wiring with an insulating layer or insulating layers in between to form storage capacitor regions and the two storage capacitor regions have substantially the same capacity.   
   
   
       14 . The display device according to  claim 13 , wherein the two storage capacitor electrodes are made of the same material and have substantially the same surface area. 
   
   
       15 . The display device according to  claim 1 , wherein the first pixel electrode and the second opposing electrode are made of a transparent material and the first opposing electrode and the second pixel electrode are made of an opaque material. 
   
   
       16 . The display device according to  claim 1 , wherein the area of the first pixel electrode in the aperture of the first region and the area of the second opposing electrode in the aperture of the second region are substantially the same. 
   
   
       17 . The display device according to  claim 16 , wherein the first pixel electrode and the second opposing electrode have substantially the same transmittance. 
   
   
       18 . The display device according to  claim 16 , wherein an opaque layer is formed on the opposing substrate for blocking light over some portion of the array substrate and some portion of the first pixel electrode or the second opposing electrode is covered with the opaque layer. 
   
   
       19 . The display device according to  claim 1 , wherein drive voltages applied to the first region and the second region have the same polarity. 
   
   
       20 . The display device according to  claim 1 , wherein the first region and the second region have substantially the same absolute value of brightness difference between the case where the pixel electrode has a positive electric potential relative to the opposing electrode and the case where the pixel electrode has a negative electric potential relative to the opposing electrode. 
   
   
       21 . A display device comprising:
 an array substrate;   an opposing substrate facing the array substrate; and   an electro-optic substance held between the array substrate and the opposing substrate,   wherein the array substrate is provided with:   a plurality of gate wirings and a plurality of source wirings intersecting each other;   a pixel electrode disposed in each region defined by two adjacent gate wirings and two adjacent source wirings;   a switching element for switching a voltage applied to the pixel electrode from the source wiring based on a signal voltage supplied from the gate wiring;   a common wiring formed between the two adjacent gate wirings;   an opposing electrode being electrically connected to the common wiring and generating an electric field for driving the electro-optic substance between the opposing electrode and the pixel electrode whereto a voltage is applied; and   an intermediate electrode disposed between the pixel electrode and the opposing electrode,   wherein the intermediate electrode has a transmittance either higher or lower than both the pixel electrode and the opposing electrode.   
   
   
       22 . The display device according to  claim 21 , wherein the pixel electrode and the opposing electrode are formed out of the same material, and the intervals between the pixel electrode and the intermediate electrode and between the intermediate electrode and the opposing electrode are substantially the same. 
   
   
       23 . The display device according to  claim 21 , wherein the intermediate electrode is resistively connected to the pixel electrode and the opposing electrode. 
   
   
       24 . The display device according to  claim 21 , wherein the intermediate electrode is subjected to capacity coupling with the pixel electrode and the opposing electrode. 
   
   
       25 . The display device according to  claim 21 , wherein the electric potential of the intermediate electrode becomes the average value of the electric potential of the pixel electrode whereto a voltage applied and the electric potential of the opposing electrode which functions as a standard electric potential. 
   
   
       26 . The display device according to  claim 1  wherein the electro-optic substance is liquid crystal. 
   
   
       27 . The display device according to  claim 26 , wherein an alternating voltage is applied to the pixel electrode. 
   
   
       28 . A method of driving a display device having:
 an array substrate;   an opposing substrate facing the array substrate; and   an electro-optic substance held between the array substrate and the opposing substrate,   the array substrate being provided with:   a plurality of gate wirings and a plurality of source wirings intersecting each other;   a pixel electrode disposed in each region defined by two adjacent gate wirings and two adjacent source wirings;   a switching element for switching a voltage applied to the pixel electrode from the source wiring based on a signal voltage supplied from the gate wiring;   a common wiring formed between the two adjacent gate wirings; and   an opposing electrode being electrically connected to the common wiring and generating an electric field for driving the electro-optic substance between the opposing electrode and the pixel electrode whereto a voltage is applied,   in the two adjacent regions each defined by two adjacent gate wirings and two adjacent source wirings the transmittance of the pixel electrode disposed in each region being higher than that of the opposing electrode disposed in the same region and the transmittance of the pixel electrode disposed in other region being lower than that of the opposing electrode disposed in that region,   said method comprising the step of inverting the voltage applied to the pixel electrode for every predetermined adjacent region.   
   
   
       29 . The method of driving a display device according to  claim 28 , wherein the predetermined regions are adjacent to each other in two directions, along the gate wiring and the source wiring. 
   
   
       30 . The method of driving a display device according to  claim 28 , wherein each predetermined region corresponds to a dot. 
   
   
       31 . The method of driving a display device according to  claim 28 , wherein the predetermined region corresponds to two dots adjacent in a direction either along the gate wiring or the source wiring. 
   
   
       32 . The method of driving a display device according to  claim 28 , wherein the predetermined region corresponds to a pixel composed of three dots of red, green and blue. 
   
   
       33 . The method of driving a display device according to  claim 28 , wherein the predetermined region corresponds to two pixels each composed of three dots of red, green and blue, adjacent in a direction either along the gate wiring or the source wiring. 
   
   
       34 - 35 . (canceled) 
   
   
       36 . A method of driving a display device having:
 an array substrate;   an opposing substrate facing the array substrate; and   an electro-optic substance held between the array substrate and the opposing substrate,   the array substrate being provided with:   a plurality of gate wirings and a plurality of source wirings intersecting each other;   a pixel electrode disposed in each region defined by two adjacent gate wirings and two adjacent source wirings;   a switching element for switching a voltage applied to the pixel electrode from the source wiring based on a signal voltage supplied from the gate wiring;   a common wiring formed between the two adjacent gate wirings; and   an opposing electrode being electrically connected to the common wiring and generating an electric field for driving the electro-optic substance between the opposing electrode and the pixel electrode whereto a voltage is applied,   the pixel electrode comprising a first pixel electrode and a second pixel electrode, and the opposing electrode comprising a first opposing electrode and a second opposing electrode,   a plurality of first regions generating an electric field between the first pixel electrode and the first opposing electrode having a lower light transmittance than the first pixel electrode being formed,   a plurality of second regions generating an electric field between the second pixel electrode and the second opposing electrode having a higher light transmittance than the second pixel electrode being formed,   said method comprising a step of inverting a voltage applied to the first pixel electrode and the second pixel electrode based on the arrangement cycles of the first region and the second region so as to flicker polarities cyclically change along both the gate wiring and the source wiring.   
   
   
       37 . The method of driving a display device according to  claim 36 , wherein said step of inverting the voltage comprises the step of inverting the flicker polarities at every dot along both the gate wiring and the source wiring. 
   
   
       38 . The method of driving a display device according to  claim 36 , wherein said step of inverting the voltage comprises the step of inverting the flicker polarities at every plurality of dots along one or both of the gate wiring and the source wiring. 
   
   
       39 . The method of driving a display device according to  claim 28 , wherein the driving frequency of the voltage applied to the pixel electrode is 60 Hz or higher. 
   
   
       40 . The display device according to  claim 21 , wherein the electro-optic substance is liquid crystal. 
   
   
       41 . The method of driving a display device according to  claim 36 , wherein the driving frequency of the voltage applied to the pixel electrode is 60 Hz or higher.