Patent Publication Number: US-2023161203-A1

Title: Pixel electrode, driving method of pixel electrode, and liquid display panel

Description:
BACKGROUND OF INVENTION 
     Field of Invention 
     The present application relates to a field of display, and particularly to a pixel electrode, a driving method of the pixel electrode, and a crystal liquid display panel. 
     Description of Prior Art 
     Liquid crystals in a type of high-quality vertical alignment (HVA) of thin film transistor liquid crystal displays (TFT-LCDs) are negative liquid crystals. Before putting the liquid crystals into use, an electric field and a polymerization technology is needed to align them. Since metal wires in the HVA of the TFT-LCDs will occupy space of pixels, a length-width ratio of a pixel electrode is large, and the larger length-width ratio usually cause an abnormal alignment of the liquid crystals, which seriously damages a light transmittance of the pixel electrode. 
     SUMMARY OF INVENTION 
     The application provides a pixel electrode, a driving method of the pixel electrode, and a liquid crystal display panel, so as to solve a problem that when a length-width ratio of an existing pixel electrode is large, it causes an abnormal alignment of liquid crystals, which seriously damage a light transmittance of the pixel electrode. 
     Firstly, the present application provides a pixel electrode, wherein the pixel electrode comprises a frame electrode and a keel electrode, the frame electrode forms a closed region, the keel electrode is located in the closed region, the keel electrode comprises at least a first trunk and a second trunk vertically intersecting the first trunk, the first trunk and the second trunk divide the closed region into four sub areas, and a shape of an area composed of any two adjacent sub areas is pagoda shaped, to improve a light transmittance of the pixel electrode. 
     In some embodiments, the first trunk and the second trunk divide the frame electrode into four segments, the four segments are arranged symmetrical to an intersection of the first trunk and the second trunk, each of the four segments comprises a first sub segment parallel to the first trunk, a second sub segment parallel to the second trunk, and a connection segment connecting the first sub segment and the second sub segment, the connection segment comprises a group of connection sub segments, the connection sub segments comprise a third sub segment parallel to the second sub segment and a fourth sub segment parallel to the first sub segment, the third sub segment and the fourth sub segment are vertically connected, a free end of the third sub segment is connected with the first sub segment, a free end of the fourth sub segment is connected with the second sub segment, a distance between the first sub segment and the first trunk is greater than a distance between the fourth sub segment and the first trunk, and a distance between the second sub segment and the second trunk is greater than a distance between the third sub segment and the second trunk. 
     In some embodiments, the first trunk and the second trunk divide the frame electrode into four segments, the four segments are arranged to be symmetrical to an intersection of the first trunk and the second trunk, each of the four segments comprises a first sub segment parallel to the first trunk, a second sub segment parallel to the second trunk, and a connection segment connecting the first sub segment and the second sub segment, the connection segment comprises N groups of connection sub segments, the number N is an integer greater than or equal to 2, each of the connection sub segments comprises a third sub segment parallel to the second sub segment and a fourth sub segment parallel to the first sub segment, the third sub segment and the fourth sub segment are vertically connected, a free end of the third sub segment of a first connection sub segment group is connected with the first sub segment, a free end of the fourth sub segment of a N th  connection sub segment group is connected with the second sub segment, and a free end of the third sub segment of a M th  connection sub segment group is connected with a free end of the fourth sub segment of a (M−1) th  connection sub segment group, wherein the number M is any integer greater than 1 and less than or equal to the number N, a distance between the first sub segment and the first trunk is greater than a distance between any of the fourth sub segments and the first trunk, and a distance between the fourth sub segment of the M th  connection sub segment group and the first trunk is less than a distance between the fourth sub segment of the (M−1) th  connection sub segment group and the first trunk, a distance between the second sub segment and the second trunk is greater than a distance between any of the third sub segments and the second trunk, and a distance between the third sub segment of the M th  connection sub segment group and the second trunk is greater than a distance between the third sub segment of the (M−1) th  connection sub segment group and the second trunk. 
     In some embodiments, a ratio of the distance between the fourth sub segment and the first trunk to the distance between the second sub segment and the second trunk is greater than or equal to 1 and less than or equal to 2.5, and a ratio of the distance between the first sub segment and the fourth sub segment to the distance between the third sub segment and the second trunk is greater than or equal to 2 and less than or equal to 3. 
     In some embodiments, a ratio of a distance between the fourth sub segment of the N th  connection sub segment group and the first trunk and the distance between the second sub segment and the second trunk is greater than or equal to 1 and less than or equal to 2.5, a ratio of a distance between the first sub segment and the fourth sub segment of the first connection sub segment group and a distance between the third sub segment of the first connection sub segment group and the second trunk is greater than or equal to 2 and less than or equal to 3, and a ratio of a distance between the fourth sub segment of the (M−1) th  connection sub segment group and the fourth sub segment of the M th  connection sub segment group and a distance between the third sub segment of the (M−1) th  connection sub segment group and the second trunk is greater than or equal to 2 and less than or equal to 3. 
     In some embodiments, a distance between the second sub segment and the third sub segment is greater than or equal to 5 μm. 
     In some embodiments, a distance between the second sub segment and the third sub segment of the N th  connection sub segment group is greater than or equal to 5 μm, and a distance between the third sub segment of the M th  connection sub segment group and the third sub segment of the (M−1) th  connection sub segment group is greater than or equal to 5 μm. 
     In some embodiments, connection points of the third sub segments and the fourth sub segments of the connection sub segment are defined as target connection points, the keel electrode further comprises at least one third trunk, and the third trunk is connected with two of the target connection points which are symmetrical to the second trunk. 
     In some embodiments, the pixel electrode further comprises a plurality of branch electrodes, the branch electrodes are respectively located in the four sub areas, and the branch electrodes in the same sub area are disposed in interval and arranged in parallel. 
     Secondly, the present application provides a driving method of a pixel electrode, wherein the driving method of the pixel electrode is used for driving the pixel electrode according to any one of the pixel electrode mentioned above, the pixel electrode comprises a right angle area located in an edge of the pixel electrode and a waist area located in a middle of the pixel electrode, and the driving method of the pixel electrode comprises: 
     applying a voltage to the pixel electrode so that a deflection electric field of the right angle area guides a deflection of liquid crystals of the waist area to improve the penetration rate of the pixel electrode. 
     Thirdly, the present application provides a liquid crystal display panel, wherein the liquid crystal display panel comprises a pixel electrode, the pixel electrode comprises a frame electrode and a keel electrode, the frame electrode forms a closed region, the keel electrode is located in the closed region, the keel electrode comprises at least a first trunk and a second trunk vertically intersecting the first trunk, the first trunk and the second trunk divide the closed region into four sub areas, and a shape of an area composed of any two adjacent sub areas is pagoda shaped, to improve a light transmittance of the pixel electrode. 
     In some embodiments, the first trunk and the second trunk divide the frame electrode into four segments, the four segments are arranged symmetrical to an intersection of the first trunk and the second trunk, each of the four segments comprises a first sub segment parallel to the first trunk, a second sub segment parallel to the second trunk, and a connection segment connecting the first sub segment and the second sub segment, the connection segment comprises a group of connection sub segments, the connection sub segments comprise a third sub segment parallel to the second sub segment and a fourth sub segment parallel to the first sub segment, the third sub segment and the fourth sub segment are vertically connected, a free end of the third sub segment is connected with the first sub segment, a free end of the fourth sub segment is connected with the second sub segment, a distance between the first sub segment and the first trunk is greater than a distance between the fourth sub segment and the first trunk, and a distance between the second sub segment and the second trunk is greater than a distance between the third sub segment and the second trunk. 
     In some embodiments, the first trunk and the second trunk divide the frame electrode into four segments, the four segments are arranged to be symmetrical to an intersection of the first trunk and the second trunk, each of the four segments comprises a first sub segment parallel to the first trunk, a second sub segment parallel to the second trunk, and a connection segment connecting the first sub segment and the second sub segment, the connection segment comprises N groups of connection sub segments, the number N is an integer greater than or equal to 2, each of the connection sub segments comprises a third sub segment parallel to the second sub segment and a fourth sub segment parallel to the first sub segment, the third sub segment and the fourth sub segment are vertically connected, a free end of the third sub segment of a first connection sub segment group is connected with the first sub segment, a free end of the fourth sub segment of a N th  connection sub segment group is connected with the second sub segment, and a free end of the third sub segment of a M th  connection sub segment group is connected with a free end of the fourth sub segment of a (M−1) th  connection sub segment group, wherein the number M is any integer greater than 1 and less than or equal to the number N, a distance between the first sub segment and the first trunk is greater than a distance between any of the fourth sub segments and the first trunk, and a distance between the fourth sub segment of the M th  connection sub segment group and the first trunk is less than a distance between the fourth sub segment of the (M−1) th  connection sub segment group and the first trunk, a distance between the second sub segment and the second trunk is greater than a distance between any of the third sub segments and the second trunk, and a distance between the third sub segment of the M th  connection sub segment group and the second trunk is greater than a distance between the third sub segment of the (M−1) th  connection sub segment group and the second trunk. 
     In some embodiments, a ratio of the distance between the fourth sub segment and the first trunk to the distance between the second sub segment and the second trunk is greater than or equal to 1 and less than or equal to 2.5, and a ratio of the distance between the first sub segment and the fourth sub segment to the distance between the third sub segment and the second trunk is greater than or equal to 2 and less than or equal to 3. 
     In some embodiments, a ratio of a distance between the fourth sub segment of the N th  connection sub segment group and the first trunk and the distance between the second sub segment and the second trunk is greater than or equal to 1 and less than or equal to 2.5, a ratio of a distance between the first sub segment and the fourth sub segment of the first connection sub segment group and a distance between the third sub segment of the first connection sub segment group and the second trunk is greater than or equal to 2 and less than or equal to 3, and a ratio of a distance between the fourth sub segment of the (M−1) th  connection sub segment group and the fourth sub segment of the M th  connection sub segment group and a distance between the third sub segment of the (M−1) th  connection sub segment group and the second trunk is greater than or equal to 2 and less than or equal to 3. 
     In some embodiments, a distance between the second sub segment and the third sub segment is greater than or equal to 5 μm. 
     In some embodiments, a distance between the second sub segment and the third sub segment of the N th  connection sub segment group is greater than or equal to 5 μm, and a distance between the third sub segment of the M th  connection sub segment group and the third sub segment of the (M−1) th  connection sub segment group is greater than or equal to 5 μm. 
     In some embodiments, connection points of the third sub segments and the fourth sub segments of the connection sub segment are defined as target connection points, the keel electrode further comprises at least one third trunk, and the third trunk is connected with two of the target connection points which are symmetrical to the second trunk. 
     In some embodiments, the pixel electrode further comprises a plurality of branch electrodes, the branch electrodes are respectively located in the four sub areas, and the branch electrodes in the same sub area are disposed in interval and arranged in parallel. 
     In some embodiments, the liquid crystal display panel further comprises a thin film transistor array substrate, a color film substrate arranged opposite to the thin film transistor array substrate, the pixel electrode arranged on one side of the thin film transistor array substrate facing the color film substrate, a common electrode arranged on one side of the color film substrate facing the thin film transistor array substrate, and a liquid crystal layer sandwiched between the pixel electrode and the common electrode. 
     In the present application, the right angle area is arranged near the waist area of the rectangular pixel electrode to form the new pixel electrode, so that a strong deflection electric field generated in the right angle area can extend to the waist area of the new pixel electrode, thus, when a length-width ratio of the pixel electrode is large, liquid crystals in a corresponding liquid crystal region can be aligned normally, and a light transmittance of the pixel electrode can be improved. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG.  1    is a schematic diagram of an existing pixel electrode. 
         FIG.  2    is a schematic diagram of a deflection of liquid crystals in a corresponding liquid crystal region under an action of a specific electric field when a length-width ratio of the pixel electrode as shown in  FIG.  1    is less than 3.5. 
         FIG.  3    is a schematic diagram of a deflection of liquid crystals in a corresponding liquid crystal region under an action of a specific electric field when a length-width ratio of the pixel electrode as shown in  FIG.  1    is greater than or equal to 3.5. 
         FIG.  4    is a schematic diagram of a first structure of a pixel electrode in an embodiment of the invention. 
         FIG.  5    is a schematic diagram of a deflection of liquid crystals in a liquid crystal region corresponding to the pixel electrode shown in  FIG.  4    under an action of different electric fields. 
         FIG.  6    is a schematic diagram of a second structure of the pixel electrode provided in an embodiment of the invention. 
         FIG.  7    is a schematic diagram of a third structure of the pixel electrode provided in an embodiment of the invention. 
         FIG.  8    is a schematic diagram of a fourth structure of the pixel electrode provided in an embodiment of the invention. 
         FIG.  9    is a schematic diagram of a deflection of the liquid crystals in the liquid crystal region corresponding to the pixel electrode shown in  FIG.  1    under an action of different electric fields. 
         FIG.  10    is a schematic diagram of a liquid crystal display panel provided in an embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
     In order to make the purpose, technical solutions and effects of the present application more clear and definite, the present application is further described in detail with reference to attached drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application. 
       FIG.  1    is a schematic diagram of an existing pixel electrode. Please refer to  FIG.  1   , where existing pixel electrodes are mostly rectangular. Please refer to  FIG.  2   , when a length-width ratio of the rectangular pixel electrode is less than 3.5, liquid crystals in a liquid crystal region corresponding to the rectangular pixel electrode can be normally aligned in a process of being illuminated by a gradually rising voltage difference, and a cross shaped dark lines appear in the liquid crystal region. Please refer to  FIG.  3   , when the length-width ratio of the rectangular pixel electrode is greater than or equal to 3.5, an alignment of the liquid crystals in the liquid crystal region corresponding to the rectangular pixel electrode is abnormal, abnormal dark lines appear in the liquid crystal region. That is, a middle part of an original cross shaped dark lines (an inner area of a dotted box shown in  FIG.  3   ) is distorted, which seriously damages a light transmittance of the pixel electrode. In order to solve a problem existing in the prior art, embodiments of the invention provide a new pixel electrode, a driving method thereof, and a liquid crystal display panel having the pixel electrode. 
     Please refer to  FIG.  4   ,  FIG.  6   ,  FIG.  7   , and  FIG.  8   , the new pixel electrode provided by an embodiment of the invention comprises a frame electrode  11  and a keel electrode  12 , the frame electrode  11  forms a closed region, the keel electrode  12  is located in the closed region, the keel electrode comprises at least a first trunk  121  and a second trunk  122  vertically intersecting the first trunk  121 . The first trunk  121  and the second trunk  122  divide the closed region into four sub areas, namely a first sub area  1111 , a second sub area  2222 , a third sub area  3333 , and a fourth sub area  4444 , wherein the first sub area  1111  is adjacent to the second sub area  2222 , the second sub area  2222  is adjacent to the third sub area  3333 , the third sub area  3333  is adjacent to the fourth sub area  4444 , and the fourth sub area  4444  is adjacent to the first sub area  1111 . A shape of an area composed of any two adjacent sub areas is pagoda shaped, that is, a shape of an area composed of the first sub area  1111  and the second sub area  2222  is pagoda shaped, a shape of an area composed of the second sub area  2222  and the third sub area  3333  is pagoda shaped, a shape of an area composed of the third sub area  3333  and the fourth sub area  4444  is pagoda shaped, and a shape of an area composed of the fourth sub area  4444  and the first sub area  1111  is pagoda shaped, to improve light transmittance of the pixel electrode. 
     The frame electrode  11  located in each of the four sub areas is in a ladder shape. Further, frame electrodes in any two adjacent sub areas are symmetrical to the first trunk  121  or the second trunk  122 . The pixel electrode shown in  FIG.  4    is used for illustration. In  FIG.  4   , the frame electrode  11  located in each of the four sub areas is in the ladder shape composed of two steps, for example, the frame electrode  11  located in the first sub area  1111  and the frame electrode  11  located in the second sub area  2222  are symmetrical to the first trunk  121 . The frame electrode  11  located in the second sub area  2222  and the frame electrode  11  located in the third sub area  3333  are symmetrical to the second trunk  122 . The frame electrode  11  located in the third sub area  3333  and the frame electrode  11  located in the fourth sub area  4444  are symmetrical to the first trunk  121 , and the frame electrode  11  located in the fourth sub area  4444  and the frame electrode  11  located in the first sub area  1111  are symmetrical to the second trunk  122 . 
       FIG.  4    is a schematic diagram of a first structure of a pixel electrode provided by an embodiment of the invention. Referring to  FIG.  4   , the pixel electrode  10  comprises the frame electrode  11  and the keel electrode  12 , the frame electrode  11  forms the closed region, the keel electrode  12  is located in the closed region, the keel electrode  12  comprises at least the first trunk  121  and the second trunk  122  vertically intersecting the first trunk  121 , the first trunk  121  and the second trunk  122  divide the frame electrode  11  into four segments, and the four segments are arranged symmetrical to an intersection of the first trunk  121  and the second trunk  122 . The first trunk  121  shown in  FIG.  4    is arranged along a horizontal direction, the second trunk  122  is arranged along a vertical direction, and the four segments are a first segment  111 , a second segment  112 , a third segment  113 , and a fourth segment  114  respectively. 
     Each of the four segments (take the first segment  111  as an example) comprises a first sub segment  100  parallel to the first trunk  121 , a second sub segment  200  parallel to the second trunk  122 , and a connection segment connecting the first sub segment  100  and the second sub segment  200 , the connection segment comprises a group of connection sub segments, the connection sub segments comprise a third sub segment  300  parallel to the second sub segment  200  and a fourth sub segment  400  parallel to the first sub segment  100 , the third sub segment  300  and the fourth sub segment  400  are vertically connected, a free end of the third sub segment  300  is connected with the first sub segment  100 , a free end of the fourth sub segment  400  is connected with the second sub segment  200 , a distance between the first sub segment  100  and the first trunk  121  is greater than a distance between the fourth sub segment  400  and the first trunk  121 , and a distance between the second sub segment  200  and the second trunk  122  is greater than a distance between the third sub segment  300  and the second trunk  122 . 
     The pixel electrode  10  provided by the embodiment of the invention will be further explained through a specific experiment. 
     It should be noted that a pixel electrode used for the experiment adopts a structure of the pixel electrode  10  as shown in  FIG.  4   , and a length-width ratio L 2 /W 1  of the pixel electrode  10  is 3.5. Please refer to  FIG.  5   , parts (a), (b), (c), (d), (e), and (f) in  FIG.  5    respectively show a deflection of liquid crystals in a liquid crystal region corresponding to the pixel electrode  10  when a voltage difference is 2.5V, 2.6V, 2.7V, 2.8V, 5V, and 8V respectively. Obviously, under any of the above voltage differences, the liquid crystals in the liquid crystal region corresponding to the pixel electrode  10  can be aligned normally, and dark lines in the liquid crystal region are all cross shaped dark lines. 
     To sum up, the pixel electrode  10  provided by the embodiment of the invention is provided with the connection sub segments in the frame electrode  11 , and each of the connection sub segments comprises the third sub segment  300  and the fourth sub segment  400  which are vertically connected. In this way, when the length-width ratio of the pixel electrode  10  is large, the liquid crystals in the corresponding liquid crystal region can be aligned normally, and the light transmittance of the pixel electrode can be improved. 
     Based on the above embodiment, please continue to refer to  FIG.  4   , a ratio of the distance between the fourth sub segment  400  and the first trunk  121  (L 1 /2) to the distance between the second sub segment  200  and the second trunk  122  (W 1 /2) is greater than or equal to 1 and less than or equal to 2.5, and a ratio of the distance between the first sub segment  100  and the fourth sub segment  400  ((l 2 −l 1 )/2) to the distance between the third sub segment  300  and the second trunk  122  (W 2 /2) is greater than or equal to 2 and less than or equal to 3. 
     Based on the above embodiment, please continue to refer to  FIG.  4   , a distance between the second sub segment  200  and the third sub segment  300  is greater than or equal to 5 μm. 
       FIG.  6    is a schematic diagram of a second structure of the pixel electrode provided by an embodiment of the invention. Referring to  FIG.  6   , the structure of the pixel electrode  10  shown in  FIG.  6    is similar to the pixel electrode  10  shown in  FIG.  4   , a difference is that a keel electrode  12  of the pixel electrode  10  shown in  FIG.  6    further comprises at least one third trunk  123 , connection points of the third sub segments  300  and the fourth sub segments  400  of the connection sub segment are defined as target connection points, and the third trunk  123  is connected with two of the target connection points which are symmetrical to the second trunk  122 . 
     Specifically, the pixel electrode  10  shown in  FIG.  6    comprises two third trunks  123 , one end of one of the third trunks  123  connects a connection point A of the third sub segment  300  and the fourth sub segment  400  in the fourth segment  114 , and the other end connects a connection point B of the third sub segment  300  and the fourth sub segment  400  in the first segment  111 ; one end of another one of the third trunks  123  connects a connection point C of the third sub segment  300  and the fourth sub segment  400  of the third segment  113 , and the other end connects a connection point D of the third sub segment  300  and the fourth sub segment  400  in the second segment  112 . 
       FIG.  7    is a schematic diagram of a third structure of the pixel electrode provided by an embodiment of the invention. Referring to  FIG.  7   , the structure of the pixel electrode  10  shown in  FIG.  7    is similar to the pixel electrode  10  shown in  FIG.  4   , a difference is that a connection segment of the pixel electrode  10  shown in  FIG.  7    comprises N groups of connection sub segments, the number N is an integer greater than or equal to 2, each of the connection sub segments comprises a third sub segment  300  parallel to the second sub segment  200  and a fourth sub segment  400  parallel to the first sub segment  100 , the third sub segment  300  and the fourth sub segment  400  are vertically connected, a free end of the third sub segment  300  of a first connection sub segment group is connected with the first sub segment  100 , a free end of the fourth sub segment  400  of a N th  connection sub segment group is connected with the second sub segment  200 , and a free end of the third sub segment  300  of a M th  connection sub segment group is connected with a free end of the fourth sub segment  400  of a (M−1) th  connection sub segment group, wherein the number M is any integer greater than 1 and less than or equal to the number N, a distance between the first sub segment  100  and the first trunk  121  is greater than a distance between any of the fourth sub segments  400  and the first trunk  121 , and a distance between the fourth sub segment  400  of the M th  connection sub segment group and the first trunk  121  is less than a distance between the fourth sub segment  400  of the (M−1) th  connection sub segment group and the first trunk  121 , a distance between the second sub segment  200  and the second trunk  122  is greater than a distance between any of the third sub segments  300  and the second trunk  122 , and a distance between the third sub segment  300  of the M th  connection sub segment group and the second trunk  122  is greater than a distance between the third sub segment  300  of the (M−1) th  connection sub segment group and the second trunk  122 . 
     Specifically, the connection segment of the pixel electrode  10  shown in  FIG.  7    comprises two groups of connection sub segments, a free end of the third sub segment  300  of the first connection sub segment group is connected with the first sub segment  100 , a free end of the fourth sub segment  400  of a second connection sub segment group is connected with the second sub segment  200 , and a free end of the third sub segment  300  of the second connection sub segment group is connected with a free end of the fourth sub segment  400  of the first connection sub segment group. The distance between the first sub segment  100  and the first trunk  121  is greater than the distance between any of the fourth sub segments  400  and the first trunk  121 , the distance between the fourth sub segment  400  of the second connection sub segment group and the first trunk  121  is less than the distance between the fourth sub segment  400  of the first connection sub segment group and the first trunk  121 , the distance between the second sub segment  200  and the second trunk  122  is greater than the distance between any of the third sub segments  300  and the second trunk  122 , and the distance between the third sub segment  300  of the second connection sub segment group and the second trunk  122  is greater than the distance between the third sub segment  300  of the first connection sub segment group and the second trunk  122 . 
     It can be understood that the structure in  FIG.  7    is generally applied to a pixel electrode with a larger length-width ratio than the pixel electrode shown in  FIG.  4   , so as to improve the light transmittance of the pixel electrode. 
     Based on the above embodiment, please continue to refer to  FIG.  7   , a ratio of a distance between the fourth sub segment  400  of the N th  connection sub segment group and the first trunk  121  and a distance between the second sub segment  200  and the second trunk  122  is greater than or equal to 1 and less than or equal to 2.5; a ratio of a distance between the first sub segment  100  and the fourth sub segment  400  of the first connection sub segment group and a distance between the third sub segment  300  of the first connection sub segment group and the second trunk  122  is greater than or equal to 2 and less than or equal to 3; and a ratio of a distance between the fourth sub segment  400  of the (M−1) th  connection sub segment group and the fourth sub segment  400  of the M th  connection sub segment group and a distance between the third sub segment  300  of the (M−1) th  connection sub segment group and the second trunk  122  is greater than or equal to 2 and less than or equal to 3. 
     Specifically, in the pixel electrode  10  shown in  FIG.  7   , a ratio of a distance between the fourth sub segment  400  of the second connection sub segment group and the first trunk  121  and a distance between the second sub segment  200  and the second trunk  122  is greater than or equal to 1 and less than or equal to 2.5; a ratio of a distance between the first sub segment  100  and the fourth sub segment  400  of the first connection sub segment group and a distance between the third sub segment  300  of the first connection sub segment group and the second trunk  122  is greater than or equal to 2 and less than or equal to 3; and a ratio of a distance between the fourth sub segment  400  of the second connection sub segment group and the fourth sub segment  400  of the first connection sub segment group and a distance between the third sub segment  300  of the first connection sub segment group and the second trunk  122  is greater than or equal to 2 and less than or equal to 3. 
     Based on the above embodiment, please continue to refer to  FIG.  7   , a distance between the second sub segment  200  and the third sub segment  300  of the N th  connection sub segment group is greater than or equal to 5 μm, and a distance between the third sub segment  300  of the M th  connection sub segment group and the third sub segment  300  of the (M−1) th  connection sub segment group is greater than or equal to 5 μm. 
     Specifically, in the pixel electrode  10  shown in  FIG.  7   , the distance between the second sub segment  200  and the third sub segment  300  of the second connection sub segment group is greater than or equal to 5 μm, and the distance between the third sub segment  300  of the second connection sub segment group and the third sub segment  300  of the first connection sub segment group is greater than or equal to 5 μm. 
       FIG.  8    is a schematic diagram of a fourth structure of the pixel electrode provided by an embodiment of the invention. Referring to  FIG.  8   , the structure of the pixel electrode  10  shown in  FIG.  8    is similar to the pixel electrode  10  shown in  FIG.  7   , a difference is that a keel electrode  12  of the pixel electrode  10  shown in  FIG.  8    further comprises at least one third trunk  123 , connection points of the third sub segments  300  and the fourth sub segments  400  of the connection sub segment are defined as target connection points, and the third trunk  123  is connected with two of the target connection points which are symmetrical to the second trunk  122 . 
     Specifically, the pixel electrode  10  shown in  FIG.  8    comprises four third trunks  123 , one end of a first one of the third trunks  123  connects a connection point E of the third sub segment  300  and the fourth sub segment  400  in the fourth segment  114 , and the other end connects a connection point F of the third sub segment  300  and the fourth sub segment  400  in the first segment  111 ; one end of a second one of the third trunks  123  connects a connection point G of the third sub segment  300  and the fourth sub segment  400  in the fourth segment  114 , and the other end connects a connection point H of the third sub segment  300  and the fourth sub segment  400  in the first segment  111 ; one end of a third one of the third trunks  123  connects a connection point I of the third sub segment  300  and the fourth sub segment  400  in the third segment  113 , and the other end connects a connection point J of the third sub segment  300  and the fourth sub segment  400  in the second segment  112 ; and one end of a fourth one of the third trunks  124  connects a connection point K of the third sub segment  300  and the fourth sub segment  400  in the third segment  113 , and the other end connects a connection point L of the third sub segment  300  and the fourth sub segment  400  in the second segment  112 . 
     Based on the above embodiment, widths of the first trunk  121 , the second trunk  122  and the third trunk  123  in the embodiments of the invention are all 6 μm. 
     Based on the above embodiment, please refer to  FIG.  4   ,  FIG.  6   ,  FIG.  7    or  FIG.  8   , in an embodiment of the invention, the first trunk  121  and the second trunk  122  divide the closed region into the four sub areas, the pixel electrode further comprises a plurality of branch electrodes  13 , the branch electrodes  13  are respectively located in the four sub areas, and the branch electrodes  13  in the same sub area are disposed in interval and arranged in parallel. 
     Specifically, the four sub areas of the pixel electrode  10  shown in  FIG.  4   ,  FIG.  6   ,  FIG.  7    or  FIG.  8    are respectively the first sub area  1111 , the second sub area  2222 , the third sub area  3333  and the fourth sub area  4444 , wherein the first sub area  1111  is surrounded by the first trunk  121 , the second trunk  122  and the first segment  111 , the second sub area  2222  is surrounded by the first trunk  121 , the second trunk  122  and the second segment  112 , the third sub area  3333  is surrounded by the first trunk  121 , the second trunk  122  and the third segment  113 , and the fourth sub area  4444  is surrounded by the first trunk  121 , the second trunk  122  and the fourth segment  114 . Several branch electrodes  13  are respectively arranged in the four sub areas, namely, the several branch electrodes  13  are divided into four branch electrode groups, and the four branch electrode groups are defined as a first branch electrode group, a second branch electrode group, a third branch electrode group and a fourth branch electrode group respectively, all of the branch electrodes  13  in the first branch electrode group are disposed in interval and arranged in parallel in the first sub area  1111 , all of the branch electrodes  13  in the second branch electrode group are disposed in interval and arranged in parallel in the second sub area  2222 , all of the branch electrodes  13  in the third branch electrode group are disposed in interval and arranged in parallel in the third sub area  3333 , and all of the branch electrodes  13  in the fourth branch electrode group are disposed in interval and arranged in parallel in the fourth sub area  4444 . 
     It should be noted that the structure of the pixel electrode  10  shown in  FIG.  4    is similar to that of the pixel electrode  10  shown in  FIG.  6   , a difference is that the pixel electrode  10  shown in  FIG.  4    lacks the third trunk  123  compared with the pixel electrode  10  shown in  FIG.  6   . Therefore, the pixel electrode  10  shown in  FIG.  4    is more conducive to forming an electric field in a same direction as an extension direction of the several branch electrodes  13 , which is more conducive to the deflection of the liquid crystals and can improve the liquid crystals efficiency. 
     The structure of the pixel electrode  10  shown in  FIG.  7    is similar to that of the pixel electrode  10  shown in  FIG.  8   , a difference is that the pixel electrode  10  shown in  FIG.  7    lacks the third trunk  123  compared with the pixel electrode  10  shown in  FIG.  8   . Therefore, the pixel electrode  10  shown in  FIG.  7    is more conducive to forming an electric field in a same direction as an extension direction of the several branch electrodes  13 , which is more conducive to the deflection of the liquid crystals and can improve the liquid crystals efficiency. 
     As a preferred embodiment, an embodiment of the invention illustrates a theoretical derivation process of the pixel electrode  10  with the above structure in combination with  FIG.  9   . It should be noted that firstly, the rectangular pixel electrode shown in  FIG.  1    is provided, as shown in part (a) of  FIG.  9   , when liquid crystals in the liquid crystal region corresponding to the rectangular pixel electrode is illuminated by a gradually rising voltage difference, there are “strong deflection electric field area” (located in inner areas of dotted boxes of the four right angle areas) which are easy to be normally aligned in the liquid crystal region, and “weak deflection electric field area” (located in inner areas of dotted boxes of the waist area) which are difficult to be normally aligned. Specifically, in a process of a gradual rise of an electric field, as shown in parts (b), (c), (d) and (e) in  FIG.  9   , the liquid crystals at the four right angles of the pixel electrode first begin to deflect under an action of the electric field, and its long axis deflection angle is consistent with a direction of several branch electrodes in the pixel electrode, under an action of a polarizer, it first transmits light, and with a further rise of the electric field, the “strong deflection electric field area” gradually guides the liquid crystals in the “weak deflection electric field area” to deflect, so a light transmission area gradually diffuses from the four right angle areas of the pixel electrode to the waist area of the pixel electrode, wherein, parts (b), (c), (d) and (e) in  FIG.  9    show the deflection of the liquid crystals in the liquid crystal region corresponding to the pixel electrode when the voltage difference is 2.5V, 2.6V, 2.7V, and 5V, respectively. 
     However, in the pixel electrode, when the right angle area is too far away from the waist area, the strong deflection electric field of the right angle area is difficult to extend to the waist area, so that the deflection of the liquid crystals in the waist area is random, and uncontrollable abnormal dark lines as shown in  FIG.  3    appear. Therefore, the pixel electrode  10  as shown in  FIG.  4   ,  FIG.  6   ,  FIG.  7    or  FIG.  8    can be formed by configuring the right angle area near the “deflection electric field weak area” to reduce a distance between the right angle area and the waist area, so that the strong deflection electric field generated by the configured right angle area can extend to the waist area, thus, liquid crystals in the liquid crystal region corresponding to the rectangular pixel electrode can be normally aligned in the process of being illuminated by the gradually rising voltage difference, and the dark lines in the liquid crystal region can be in a regular cross shape, thereby improving the light transmittance of the pixel electrode. 
     The pixel electrode  10  as shown in  FIG.  4    is formed after the right angle area is arranged near the “deflection electric field weak area”, during the gradual rise of the electric field, numbers of the “strong deflection electric field area” in the liquid crystal region corresponding to the pixel electrode  10  increases to 8 as shown in  FIG.  5   , in which, the strong deflection electric field in the right angle area near the waist area can guide the deflection of the liquid crystals in the “weak deflection electric field area” of the waist area, so that the liquid crystals in the liquid crystal region corresponding to the pixel electrode  10  can be normally aligned in the process of being illuminated by the gradually rising voltage difference, thereby the dark lines in the liquid crystal region are in a regular cross shape, thus improving the light transmittance of the pixel electrode. 
     Based on the above embodiment, an embodiment of the invention also provides a driving method of the pixel electrode. The driving method of the pixel electrode is used to drive the pixel electrode described in any of the above embodiments. The pixel electrode comprises a right angle area in an edge of the pixel electrode and a waist area located in a middle of the pixel electrode. The driving method of the pixel electrode comprises: 
     Applying a voltage to the pixel electrode so that a deflection electric field of the right angle area guides a deflection of liquid crystals of the waist area to improve the penetration rate of the pixel electrode. It should be noted that a working principle of the above-mentioned pixel electrode after applying voltage has been described in detail in the embodiment, and it will not be described here. 
     Based on the above embodiment, please refer to  FIG.  10   , an embodiment of the invention also provides a liquid crystal display panel  1 , the liquid crystal display panel  1  comprises the pixel electrode  10  described in any of the above embodiments. It should be noted that the above embodiments have described a structure and a function of the pixel electrode  10  in detail, and it will not be repeated here. 
     Based on the above embodiment, the liquid crystal display panel  1  of the embodiment of the invention also comprises a thin film transistor array substrate  201 , a color film substrate  202  arranged opposite to the thin film transistor array substrate  201 , the pixel electrode  10  arranged on one side of the thin film transistor array substrate  201  facing the color film substrate  202 , and a common electrode  203  arranged on one side of the color film substrate  202  facing the thin film transistor array substrate  201 , and a liquid crystal layer  204  sandwiched between the pixel electrode  10  and the common electrode  203 . 
     It can be understood that for those skilled in the art, equivalent replacements or changes can be made according to the technical solutions of the present application and its application concept, and all these changes or replacements shall fall within a protection scope of claims attached to the present application.