Patent Publication Number: US-2018039144-A1

Title: Liquid crystal panels and display devices

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present disclosure relates to liquid crystal display technology, and more particularly to a liquid crystal panel and a display device. 
     2. Discussion of the Related Art 
     The liquid crystal display panel is the most widely used flat panel display, which has been adopted as high-resolution color display in a variety of electronic devices such as mobile phones, personal digital assistants (PDA), a digital camera, a laptop computer screen. With the development and progress of the liquid crystal display panel technology, higher demands toward display performance, design, low cost and high transmittance are increased. 
     With respect to the LCD IPS mode (flat control) display panel, viewers can only see the short axis of the liquid crystal molecules at any moments, such that the images remain quite the same when the viewing angles are different. As such, the viewing angle of the liquid crystal panel of IPS mode may be enhanced. However, as shown in  FIGS. 1 and 2 , within the internal structure of the liquid crystal panel, the ITO layer includes a pixel electrode layer  121  and a common electrode layer  122 . The driving voltages applied to the pixel electrode layer  121  are equal such that the voltage differences between the common electrode layer  122  and the adjacent pixel electrode layer  121  are the same. In addition, as the common electrode layer  122  and the pixel electrode layer  121  are arranged on the same side of the substrate, the strength of the horizontal electrical field above the common electrode layer  122  is weak and it is difficult for the liquid crystals to rotate. As such, the transmission rate of the liquid crystal panel of IPS mode is low, and the display performance may be affected. 
     In view of the above, it is necessary to provide a liquid crystal panel and a display device to overcome the above problems. 
     SUMMARY 
     The present disclosure relates to a liquid crystal panel and a display device for enhancing the strength of the horizontal electrical field above the common electrode layer so as to enhance the display performance. 
     In one aspect, a liquid crystal panel includes: a first substrate, a second substrate spaced apart from the first substrate, and a liquid crystal layer between the first substrate and the second substrate, the second substrate includes an ITO layer facing toward the liquid crystal layer, the ITO layer includes at least one first pixel electrode layer, at least one common electrode layer, and at least one second pixel electrode layer spaced apart from each other, and a first voltage difference between the first pixel electrode layer and the common electrode layer is different from a second voltage difference between the second pixel electrode layer and the common electrode layer; wherein the first voltage difference between the first pixel electrode layer and the common electrode layer is opposite to the second voltage difference between the second pixel electrode layer and the common electrode layer; the common electrode layer is arranged between the first pixel electrode layer and the second pixel electrode layer, and the first pixel electrode layer or the second pixel electrode layer is arranged between two common electrode layers; and the liquid crystal panel is the liquid crystal panel of IPS mode. 
     Wherein a first driving voltage value of the first pixel electrode layer is different from a second driving voltage value of the second pixel electrode layer. 
     Wherein a voltage value of the common electrode layer is larger than the first driving voltage value of the adjacent first pixel electrode layer, and is smaller than the second driving voltage value of the adjacent second pixel electrode layer. 
     Wherein the first substrate is a color filter array substrate, and the second substrate is a thin film transistor (TFT) array substrate. 
     In another aspect, a liquid crystal panel includes: a first substrate, a second substrate spaced apart from the first substrate, and a liquid crystal layer between the first substrate and the second substrate, the second substrate includes an ITO layer facing toward the liquid crystal layer, the ITO layer includes at least one first pixel electrode layer, at least one common electrode layer, and at least one second pixel electrode layer spaced apart from each other, and a first voltage difference between the first pixel electrode layer and the common electrode layer is different from a second voltage difference between the second pixel electrode layer and the common electrode layer. 
     Wherein the common electrode layer is arranged between the first pixel electrode layer and the second pixel electrode layer, and the first pixel electrode layer or the second pixel electrode layer is arranged between two common electrode layers. 
     Wherein a first driving voltage value of the first pixel electrode layer is different from a second driving voltage value of the second pixel electrode layer. 
     Wherein a voltage value of the common electrode layer is larger than the first driving voltage value of the adjacent first pixel electrode layer, and is smaller than the second driving voltage value of the adjacent second pixel electrode layer. 
     Wherein the first voltage difference is in a range between 0 and 10V and the second voltage difference is in a range between −10 and 0 V. 
     Wherein the second voltage difference is in a range between 0 and 10 V, and the first voltage difference is in a range between −10 and 0 V. 
     Wherein the liquid crystal panel is the liquid crystal panel of IPS mode. 
     Wherein the first substrate is a color filter array substrate, and the second substrate is a TFT array substrate. 
     In another aspect, a display device includes: a liquid crystal panel including a first substrate, a second substrate spaced apart from the first substrate, and a liquid crystal layer between the first substrate and the second substrate, the second substrate includes an ITO layer facing toward the liquid crystal layer, the ITO layer includes at least one first pixel electrode layer, at least one common electrode layer, and at least one second pixel electrode layer spaced apart from each other, and a first voltage difference between the first pixel electrode layer and the common electrode layer is different from a second voltage difference between the second pixel electrode layer and the common electrode layer. 
     Wherein the common electrode layer is arranged between the first pixel electrode layer and the second pixel electrode layer, and the first pixel electrode layer or the second pixel electrode layer is arranged between two common electrode layers. 
     Wherein a first driving voltage value of the first pixel electrode layer is different from a second driving voltage value of the second pixel electrode layer. 
     Wherein a voltage value of the common electrode layer is larger than the first driving voltage value of the adjacent first pixel electrode layer, and is smaller than the second driving voltage value of the adjacent second pixel electrode layer. 
     Wherein the first voltage difference is in a range between 0 and 10V and the second voltage difference is in a range between −10 and 0 V. 
     Wherein the second voltage difference is in a range between 0 and 10 V, and the first voltage difference is in a range between −10 and 0 V. 
     Wherein the liquid crystal panel is the liquid crystal panel of IPS mode. 
     Wherein the first substrate is a color filter array substrate, and the second substrate is a TFT array substrate. 
     In view of the above, the first voltage difference between the common electrode layer and the first pixel electrode layer is different from the second voltage difference between the common electrode layer and the second pixel electrode layer. The intensity of the horizontal electrical field above the common electrode layer may be increased and the transmission rate of the liquid crystal panel may also be enhanced. In addition, the performance of the liquid crystal panel may be enhanced, and the design cost may be reduced. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic view of the conventional liquid crystal panel. 
         FIG. 2  is a schematic view of the transmission rate of the liquid crystal panel of  FIG. 1  along the locations of the electrode layer of 
         FIG. 3  is a schematic view of the liquid crystal panel in accordance with one embodiment. 
         FIG. 4  is a schematic view of the transmission rate of the liquid crystal panel of  FIG. 3  along the locations of the electrode layer of 
         FIG. 5  is a comparison diagram of the transmission rates of the liquid crystal panel of the claimed invention and of the conventional liquid crystal panel. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Embodiments of the invention will now be described more fully hereinafter with reference to the accompanying drawings, in which embodiments of the invention are shown. 
     The present disclosure relates to a display device including a liquid crystal panel. Preferably, the liquid crystal panel is the liquid crystal panel of IPS mode. Specifically, the liquid crystal panel may be the liquid crystal panel adopting a brand new liquid crystal configuration for overcoming the shortages of the TN mode regarding the first generation IPS, so as to realize a better visible angle. In another example, the liquid crystal panel may be the liquid crystal panel adopting the second generation IPS technology, i.e., S-IPS or Super-IPS, which includes “ ”-shaped electrode and a dual-domains mode. With such configuration, the grayscale reverse phenomenon at some specific angles may be enhanced. In another example, the liquid crystal panel may be the liquid crystal panel adopting the third generation IPS technology, i.e., AS-IPS or Advanced Super-IPS, which decreases the gap between the liquid crystal molecules to increase the aperture rate and to enhance the brightness. 
       FIG. 3  is a schematic view of the liquid crystal panel in accordance with one embodiment. The liquid crystal panel includes a first substrate  21 , a second substrate  22  spaced apart from the first substrate  21 , and a liquid crystal layer  23  between the first substrate  21  and the second substrate  22 . In the embodiment, the first substrate  21  is a color filter array substrate, and the second substrate  22  is a thin film transistor (TFT) array substrate. 
     The second substrate  22  includes an ITO layer facing toward the liquid crystal layer. The ITO layer includes a plurality of first pixel electrode layers  221 , common electrode layers  222 , and second pixel electrode layers  223  spaced apart from each other. Preferably, the common electrode layer  222  is arranged between the first pixel electrode layer  221  and the second pixel electrode layer  223 . One first pixel electrode layer  221  or one second pixel electrode layer  223  is arranged between two common electrode layers  222 . Specifically, the ITO layer is configured with the cyclical sequence including first pixel electrode layer  221 , the common electrode layer  222 , and the second pixel electrode layer  223 , and the common electrode layer  222 . 
     It should be understood that the ITO layer is not limited to the above sequence. In other embodiments, the common electrode layer  222  is arranged between two first pixel electrode layers  221 , and the common electrode layer  222  is arranged between the two second pixel electrode layers  223 . 
     A first driving voltage value of the first pixel electrode layer  221  is different from a second driving voltage value of the second pixel electrode layer  223 , and the driving voltage values of each of the common electrode layers  222  are equal. Thus, in the embodiment, the first voltage difference between the first pixel electrode layer  221  and the common electrode layer  222  is different from the second voltage difference between the second pixel electrode layer  223  and the common electrode layer  222 . Thus, as the first driving voltage value is different from the second driving voltage value, the magnetic field above the common electrode layer  222  may change. Compared to the original magnetic field, the magnetic field above the common electrode layer  222  increases greatly so as to change the transmission rate around and above the common electrode layer  222 , which also increases the transmission rate of the liquid crystal panel. 
     In the embodiment, the first voltage difference is in a range between 0 and 10V and the second voltage difference is in a range between −10 and 0 V. In other embodiments, the second voltage difference may be in a range between 0 and 10 V, and the first voltage difference may be in a range between −10 and 0 V. The voltage difference may be configured in accordance with real scenarios. 
     In the embodiment, the voltage value of the common electrode layer  222  is larger than the first driving voltage value of the adjacent first pixel electrode layer  221 , and is smaller than the second driving voltage value of the adjacent second pixel electrode layer  223 . It can be understood that, in the other embodiment, the voltage value of the common electrode layer  222  is smaller than the first driving voltage value of the adjacent first pixel electrode layer  221 , and is greater than the second driving voltage value of the adjacent second pixel electrode layer  223   
     Preferably, the first voltage difference between the first pixel electrode layer  221  and the common electrode layer  222  is opposite to the second voltage difference between the second pixel electrode layer  223  and the common electrode layer  222 . For instance, the first voltage difference between the first pixel electrode layer  221  and the common electrode layer  222  is 5V, and the second voltage difference between the second pixel electrode layer  223  and the common electrode layer  222  is −5V. The voltage difference may be configured in accordance with real scenarios. As the locations of the first pixel electrode layer  221 , the common electrode layer  222 , and the second pixel electrode layer  223  are different, in order to enhance the transmission rate, the first voltage difference between the first pixel electrode layer  221  and the common electrode layer  222  may be configured to be not opposite to the second voltage difference between the second pixel electrode layer  223  and the common electrode layer  222 . For instance, the first voltage difference between the first pixel electrode layer  221  and the common electrode layer  222  is 5V, and the second voltage difference between the second pixel electrode layer  223  and the common electrode layer  222  is −6V. That is, the voltage difference may be configured in accordance with real scenarios. 
     As shown in  FIG. 4 , the x-axis represents the locations of the pixel electrode layers and the common electrode layers on the second substrate, the left y-axis represents the distance between the first substrate  21  and the second substrate  22 , and the right y-axis represents the transmission rate of the display panel. As the first driving voltage value of the first pixel electrode layer  221  is different from the second driving voltage value of the second pixel electrode layer  223 , the first voltage difference (V 1 ) between the common electrode layer  222  and the first pixel electrode layer  221  is different from the second voltage difference (V 2 ) between the common electrode layer  222  and the second pixel electrode layer  223 . In this way, the horizontal electrical field above the common electrode layer  222  increases and the liquid crystal may be rotated easily, which increases the transmission rate above the common electrode layer  222 . Specifically, referring to  FIG. 2 , the transmission rate above the common electrode layer  122  is 0.5. Referring to  FIG. 3 , in the embodiment, the transmission rate above the common electrode layer  222  reaches 0.8. that is, the transmission rates of the first pixel electrode layer  221  and the second pixel electrode layer  223  remain the same, and the transmission rate above the common electrode layer  222  increases about 0.5 times. That is, the transmission rate above the common electrode layer  222  increases from the 0.5 toward 0.8. Conventionally, the pixel electrode layer and the common electrode layer are arranged on the TFT array substrate, and the transmission rate of those far away from the TFT array substrate is low. With the increase of the altitude, the transmission rate decreases. On the contrary, the present disclosure may control the driving voltage of the pixel electrode layer such that the transmission rate may not decrease when the altitude increases, which can effectively reduce the cost. 
     Further, not only the transmission rate may be increased, the power consumption of the display panel may be reduced. As shown in  FIG. 5 , the x-axis represents the driving voltage, the y-axis represents the transmission rate, solid lines represent the curve of the present disclosure, and the dashed lines represents the curve of the conventional technology. In view of  FIG. 5 , the driving voltage is about 5.5V when the transmission rate in one embodiment reaches the maximum value, i.e., one. With respect to the conventional technology, the driving voltage is about 6V when the transmission rate reaches the maximum value, i.e., 0.95. It is clear that the driving voltage may be reduced for 0.5 V. In addition, not only the transmission rate is increased, the power consumption of the display panel may be reduced also. 
     In view of the above, the liquid crystal panel includes the first substrate, the second substrate spaced apart from the first substrate, and the liquid crystal layer between the first substrate and the second substrate. The second substrate includes the ITO layer facing toward the liquid crystal layer. The ITO layer includes the first pixel electrode layer, the common electrode layer, and the second pixel electrode layer spaced apart from each other. The first voltage difference between the common electrode layer and the first pixel electrode layer is different from the second voltage difference between the common electrode layer and the second pixel electrode layer. In view of the above, the intensity of the horizontal electrical field above the common electrode layer may be increased and the transmission rate of the liquid crystal panel may also be enhanced. In addition, the performance of the liquid crystal panel may be enhanced, and the design cost may be reduced. 
     It is believed that the present embodiments and their advantages will be understood from the foregoing description, and it will be apparent that various changes may be made thereto without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the examples hereinbefore described merely being preferred or exemplary embodiments of the invention.