Liquid crystal display and driving method thereof

Abstract

The present invention discloses a liquid crystal display and a driving method thereof to speed up a bend alignment at an initial operation such as right after power on in the liquid crystal display with OCB mode. According to the present invention, the LCD, which includes a LCD panel, a source driver outputting image signals and a gate driver sequentially outputting scanning signals, at an initial operation, is controlled to output external bias voltages to common electrode lines and simultaneously to stop the driving of the gate driver and the source driver, according as a first time passes, is controlled to output specific common electrode voltages thereto instead of the external bias voltages and simultaneously to perform a driving of the source driver and the gate driver. As a result, at an initial operation, by applying high-level bias voltages instead of the common electrode voltages to the common electrode lines and simultaneously stopping the driving of the gate driver, the source driver and a back light, the speed of the initial bend alignment of a liquid crystal with OCB mode can be made to be high.

1 - 16 . (canceled)  
   
   
       17 . A liquid crystal display comprising: 
 an LCD panel;    a source driver outputting image signals to the LCD panel; and    a gate driver sequentially outputting scanning signals to the LCD panel,    wherein at the same time of power on, high-level bias voltages are applied to a common electrode line of the LCD panel, and simultaneously, driving of the source driver and the gate driver are stopped and after a specific time has passed, common electrode voltages are applied to the common electrode lines of the liquid crystal display instead of the high-level bias voltages and signals for driving the source driver and the gate driver.    
   
   
       18 . The liquid crystal display of  claim 17 , wherein the LCD panel has a liquid crystal with an OCB mode.  
   
   
       19 . The liquid crystal display of  claim 17 , wherein the high-level bias voltages are provided from an external device.  
   
   
       20 . The liquid crystal display of  claim 17 , wherein the high-level bias voltages are generated on the basis of supply voltages provided to the gate driver.  
   
   
       21 . A liquid crystal display comprising: 
 an LCD panel; and    a back light unit to output a light to the LCD panel;    wherein high-level bias voltages are applied to a common electrode of the LCD panel, and simultaneously, and the back light unit is stopped, and after a specific time has passed, common electrode voltages are applied to the common electrode of the liquid crystal display instead of the high-level bias voltages.    
   
   
       22 . The liquid crystal display of  claim 21 , wherein the high-level bias voltages are applied to the common electrode of the LCD panel at the same time of power on.  
   
   
       23 . The liquid crystal display of  claim 21 , further comprising; 
 a source driver outputting image signals to the LCD panel; and    a gate driver sequentially outputting scanning signals to the LCD panel,    wherein the high-level bias voltages are applied to the common electrode of the LCD panel, and simultaneously, driving of the source driver, the gate driver are stopped.    
   
   
       24 . The liquid crystal display of  claim 21 , wherein signals for driving the source driver, the gate driver and the back light unit are outputted, respectively when the common electrode voltages are applied to the common electrode of the liquid crystal display.  
   
   
       25 . The liquid crystal display of  claim 21 , wherein at an initial operation of the liquid crystal display, voltages applied to the common electrode lines are high-level bias voltages repeating on and off.  
   
   
       26 . The liquid crystal display of  claim 21 , wherein at an initial operation of the liquid crystal display, the voltages applied to the common electrode lines are voltages that either the high level bias voltages or the common electrode voltages are repeatedly applied.  
   
   
       27 . The liquid crystal display of  claim 21 , wherein at an initial operation, the LCD panel is kept in a floating state.  
   
   
       28 . The liquid crystal display of  claim 27 , wherein the LCD panel comprises pixel electrodes kept in the floating state until the liquid crystal substantially turns into a bend alignment.  
   
   
       29 . A method for driving a liquid crystal display comprising an LCD panel having a liquid crystal, a gate driver and a source driver, the method comprising: 
 (a) forcibly stopping the driving of the gate driver and the source driver simultaneously as initially starting the LCD;    (b) applying high-level bias voltages supplied independently to the common electrode lines of the LCD panel to substantially induce a tilt angle of a liquid crystal molecules in a center of a liquid crystal layer 90°;    (c) driving the gate driver and the source driver after a certain time has passed; and    (d) applying common electrode voltages to the common electrode lines instead of the high-level bias voltages.    
   
   
       30 . The method of  claim 29 , wherein the liquid crystal display further comprises back light unit and the method further comprises forcibly stopping the back light unit simultaneously as initially starting the LCD.  
   
   
       31 . The method of  claim 30 , the method further comprising, after step (d), applying a specific back light driving voltage to the back light.  
   
   
       32 . The method of  claim 29 , wherein the LCD panel has a liquid crystal with an OCB mode.  
   
   
       33 . The method of  claim 29 , wherein at an initial operation of the LCD, the voltages applied to the common electrode lines are high-level bias voltages applied once thereto.  
   
   
       34 . The method of  claim 29 , wherein at an initial operation of the liquid crystal display, the voltages applied to the common electrode lines are high-level bias voltages repeating on and off.  
   
   
       35 . The method of  claim 29 , wherein at an initial operation of the liquid crystal display, the voltages applied to the common electrode lines are voltages that either the high-level bias voltages or the common electrode voltages repeatedly applied.