Liquid crystal display

Abstract

Portions of a liquid crystal layer and an alignment layer in an LCD which are electrically connected to a scan signal line or to a gate electrode are protected from exposure. Such an LCD can be formed from a five step photo lithographic process. Pixel electrodes A 11 and B 11 are connected to a common display signal line Dm. TFTs M 1 and M 2 are connected in series between the pixel electrode A 11 and the display signal line Dm. A TFT M 3 is connected between the pixel electrode B 11 and the display signal line Dm. TFTs M 1 and M 3 use a scan signal line Gn+1 as respective gate electrodes thereof. TFT M 2 uses a scan signal line Gn+2′ branched from a scan signal line Gn+2 as a gate electrode thereof. The scan signal lines Gn+1 and Gn+2′ are arranged parallel to each other inside a display region. The semiconductor layer structure of the LCD is also disclosed.

1 . An image display device having pixel electrodes arranged in rows and columns of a matrix, the image display device comprising: 
 a plurality of display device elements arranged in a column, each of said display device elements including: 
 first and second pixel electrodes supplied with a display signal in a time-division multiplexed manner through a common display signal line;  
 first and second switching elements between the common display signal line and the first pixel electrode;  
 a third switching element between the common display signal line and the second pixel electrode;  
 a first scan signal line for transmitting a scan signal to the first and third switching elements; and  
 a second scan signal line parallel to the first scan signal line, for transmitting a scan signal to the second switching element, and  
 wherein the second scan signal line is branched from the first scan signal line in the display device element.  
   
   
   
       2 . The image display device according to  claim 1 ,  
     wherein the second scan signal line is branched from the first scan signal line in the display device element located downstream of that of the second scan signal line, and 
 further comprising a storage capacitor formed between each of the first and second pixel electrodes in the display device element and the first scan signal line in the display device element located upstream of that of the first and second pixel electrodes.  
 
   
   
       3 . The image display device according to  claim 1 , 
 wherein the first and second switching elements are connected in series between the first pixel electrode and the display signal line.    
   
   
       4 . The image display device according to  claim 3 , further comprising: 
 a passivation film layer for protecting the second switching element, and    wherein part of the second scan signal line connected to the second switching element is formed on the passivation film layer.    
   
   
       5 . The image display device according to  claim 1 , 
 wherein the second scan signal line is provided between the first scan signal line and the first and second pixel electrodes and intersects with the first scan signal line outside an image display region.    
   
   
       6 . The image display device according to  claim 5 , further comprising: 
 a passivation film layer for protecting the second switching element, and    wherein part of the second scan signal line connected to the second switching element is formed on the passivation film layer outside the image display region.    
   
   
       7 . The image display device according to  claim 1 , wherein 
 the second scan signal line, which is branched from the first scan signal line in the display device element located downstream of that of the second scan signal line, is provided between the first scan signal line and the first and second pixel electrodes and intersects with the first scan signal line outside an image display region,    the first and second switching elements are connected in series between the first pixel electrode and the display signal line, and    part of the second scan signal line connected to the second switching element is formed on a passivation film layer for protecting the second switching element outside the image display region, and further comprising    a storage capacitor between each of the first and second pixel electrodes and the first scan signal line in the display device element located upstream of that of the first and second pixel electrodes.    
   
   
       8 . An image display apparatus having an image display region in which pixel electrodes are arranged in rows and columns of a matrix and an image non-display region located outside of the image display region, the image display apparatus comprising: 
 a display signal supplying circuit for supplying display signals;    a scan signal supplying circuit for supplying scan signals;    a plurality of parallel display signal lines for transmitting the display signals to the pixel electrodes;    a plurality of parallel scan signal lines for transmitting the scan signals to the pixel electrodes;    first and second pixel electrodes located between the nth (where n is a positive integer) scan signal line and the (n+1)th scan signal line and receiving the display signals from a predetermined one of the display signal lines;    first and second switching elements connected in series between the predetermined display signal line and the first pixel electrode; and    a third switching element connected between the predetermined display signal line and the second pixel electrode, and    wherein the scan signal transmitted through the (n+1)th scan signal line controls ON and OFF of the first and third switching elements, and    the scan signal transmitted through a branched scan signal line which is branched from the (n+2)th scan signal line located downstream of the (n+1)th scan signal line controls ON and OFF of the second switching element.    
   
   
       9 . The image display apparatus according to  claim 8 , 
 wherein the branched scan signal line branched from the (n+2)th scan signal line in the image non-display region includes a first portion which extends in a column direction in the image non-display region and a second portion which is connected to the first portion to extend in a row direction, and    the branched scan signal line intersects with the (n+1)th scan signal line in the image non-display region.    
   
   
       10 . An image display apparatus having an image display region in which pixel electrodes are arranged in rows and columns of a matrix and an image non-display region located around the image display region, the image display apparatus comprising: 
 a display signal supplying circuit for supplying display signals;    a scan signal supplying circuit for supplying scan signals;    a plurality of parallel display signal lines for transmitting the display signals to the pixel electrodes;    a plurality of parallel scan signal lines for transmitting the scan signals to the pixel electrodes;    first and second pixel electrodes located between the nth (where n is a positive integer) scan signal line and the (n+1)th scan signal line and receiving the display signals from a predetermined one of the display signal lines;    first and second switching elements connected in series between the predetermined display signal line and the first pixel electrode; and    a third switching element connected between the predetermined display signal line and the second pixel electrode, and    wherein the scan signal transmitted through the nth scan signal line controls ON and OFF of the first and third switching elements, and    the scan signal transmitted through a branched scan signal line which is branched from the (n+1)th scan signal line controls ON and OFF of the second switching element.    
   
   
       11 - 14 . (canceled)