Abstract:
A liquid crystal display (LCD) panel comprising a signal line, a first dielectric layer, a liquid crystal layer, a pixel electrode, and a thin film transistor (TFT) is provided. The first dielectric layer with a first permittivity ε 1  is formed on the signal line and the TFT. An average permittivity of the liquid crystal layer is a second permittivity ε 2  greater than the first permittivity ε 1.  The pixel electrode neighbors with the signal line. The distance between the signal line and a side of the first dielectric layer is a first distance d 1,  and the distance between a side of the first dielectric layer and a side of the pixel electrode is a second distance d 2,  wherein the second permittivity ε 2,  the first permittivity ε 1,  the first distance d 1  and the second distance d 2  are conformed to the following equation: 
     
       
         
           
             
               
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Description:
[0001]    This application claims the benefit of Taiwan application Serial No. 102106256, filed Feb. 22, 2013, the subject matter of which is incorporated herein by reference. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The invention relates in general to a display panel, and more particularly to a liquid crystal display (LCD) panel. 
         [0004]    2. Description of the Related Art 
         [0005]    In recent years, liquid crystal display (LCD) panel has been widely used in display screen of electronic products. The LCD panel has many different implementations such as twister nematic (TN) display, super twisted nematic (STN) display, in-plane switching (IPS) display, and multi-domain vertical alignment (MVA) display. A vertical electrical field or a horizontal electrical field can be applied to the LCD panel for controlling the rotation direction of liquid crystal molecules and adjusting the polarizing direction of the light. Consequentially, light flux is affected and contrast effect of bright state and dark state can be achieved. 
         [0006]    The LCD panel comprises a plurality of pixel regions. Each of the pixel regions can be divided into a non-opening area and an opening area. The non-opening area, defined as the area outside the opening area, has a thin film transistor (TFT) and a plurality of signal traces. The black matrix (BM) of conventional LCD panel is disposed in the non-opening area. The size of the black matrix is equivalent to the non-opening area such that the light will not be leaked via the non-opening area. However, the design of the black matrix and the non-opening area having equivalent size deteriorates aperture ratio, increase manufacturing cost, and accordingly jeopardize market competitiveness. 
       SUMMARY OF THE INVENTION 
       [0007]    The invention is directed to a liquid crystal display (LCD) panel whose black matrix only needs to be disposed in a transistor area of a pixel region and does not need to be extended to a non-transistor area, hence increasing aperture ratio, reducing the manufacturing cost, and accordingly enhancing market competitiveness. 
         [0008]    According to one embodiment of the present invention, a liquid crystal display (LCD) panel comprising a signal line, a first dielectric layer, a liquid crystal layer, a pixel electrode, and a thin film transistor (TFT) is provided. The first dielectric layer has a first permittivity ε 1  is formed on the signal line and the TFT. An average permittivity of the liquid crystal layer is the second permittivity ε 2 , wherein the second permittivity ε 2  is greater than the first permittivity ε 1 . The pixel electrode neighbors with the signal line. The distance between the signal line and a side of the first dielectric layer is a first distance d 1 , and the distance between a side of the first dielectric layer and a side of the pixel electrode is a second distance d 2 . The second permittivity ε 2 , the first permittivity ε 1 , the first distance d 1  and the second distance d 2  are conformed to the following equation: 
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         [0000]    The threshold voltage Vth is a threshold voltage making the transmittance of the liquid crystal layer start to increase. The Vd is a driving voltage making the transmittance of the LCD panel reach a maximum transmittance if the signal line is a data line, and the Vd is a voltage difference between VGL and the pixel electrode if the signal line is a scan line. The VGL is a gate low voltage of the scan line and a transmittance of a region between the signal line and the side of the pixel electrode is less than 0.1% and more than 0%. 
         [0009]    The above and other aspects of the invention will become better understood with regard to the following detailed description of the preferred but non-limiting embodiment(s). The following description is made with reference to the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]      FIG. 1  is a cross-sectional view of an LCD panel; 
           [0011]      FIG. 2  is a schematic diagram illustrating transmittance varying with voltage; 
           [0012]      FIG. 3  is a cross-sectional view of an LCD panel according to a first embodiment; 
           [0013]      FIG. 4  is a cross-sectional view of an LCD panel according to a second embodiment; 
           [0014]      FIG. 5  is a cross-sectional view of an LCD panel according to a third embodiment; 
           [0015]      FIG. 6  is a cross-sectional view of an LCD panel according to a fourth embodiment; 
           [0016]      FIG. 7  is a cross-sectional view of an LCD panel according to a fifth embodiment; 
           [0017]      FIG. 8  is a cross-sectional view of an LCD panel according to a sixth embodiment. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0018]    Referring to  FIG. 1  and  FIG. 2  at the same time.  FIG. 1  is a cross-sectional view of an LCD panel.  FIG. 2  is a schematic diagram illustrating transmittance varying with voltage. The LCD panel  1  comprises a metal layer  9 , a protection layer  10 , a signal line  11 , a first dielectric layer  12 , a liquid crystal layer  13 , a pixel electrode  14 , a pixel electrode  14 ′, a thin film transistor (TFT)  15 , a first substrate  16 , a second substrate  17 , a black matrix (BM)  18 , a protrusion  21 , a polarizer  22  and a polarizer  23 . The LCD panel  1  can be divided into a non-opening area and an opening area  1   c.  The non-opening area further comprises a transistor area  1   a  and a non-transistor area  1   b.  The non-transistor area  1   b  refers to a region between a side of the transistor area  1   a  and a side of the pixel electrode  14  closest to the transistor area  1   a.  The non-transistor area  1   b  is between the transistor area  1   a  and the opening area  1   c.    
         [0019]    It should be noted that the transistor area  1   a  is different from the non-opening area of a conventional LCD panel, and the non-transistor area  1   b  is different from the opening area of the conventional LCD panel. The non-opening area of the conventional LCD panel must comprise a TFT  15  and a signal line  11 . Relatively, the transistor area  1   a  defined in the LCD panel  1  of the present invention only comprises a TFT  15  but not the signal line  11 . The non-transistor area  1   b  is defined as a region between a side of the TFT  15  and the side of the pixel electrode  14  closest to the signal line  11 . The transistor area  1   a  is less than the non-opening area of the conventional LCD panel. 
         [0020]    The black matrix  18  is disposed in the transistor area  1   a  instead of the non-transistor area  1   b.  The metal layer  9 , the protection layer  10 , the signal line  11 , the first dielectric layer  12 , the liquid crystal layer  13 , the pixel electrode  14 , the pixel electrode  14 ′, the TFT  15 , the black matrix  18  and the protrusion  21  are located between the first substrate  16  and the second substrate  17 . The first substrate  16  and the second substrate  17  are located between the polarizer  22  and the polarizer  23 . The first dielectric layer  12  is formed on the signal line  11  and the TFT  15 . The first dielectric layer  12  is a transparent material, and can be realized by such as an insulating layer, a color filter or a combination thereof. The first dielectric layer  12  has a first permittivity ε 1 . The first permittivity ε 1  is greater than 0 and less than or equal to 10. 
         [0021]    The first substrate  16  and the second substrate  17  are formed by a transparent material, and the transparency of the first substrate  16  and the second substrate  17  is above 90%. When the first dielectric layer  12  is realized by an insulating layer formed by a transparent material, the transparency of the first dielectric layer  12  is above 90%. When the first dielectric layer  12  is realized by a color filter, the first dielectric layer  12  still allows a light with a specific waveband to pass through. The transparency of the color filter is about ⅓ of that of the insulating layer. 
         [0022]    The protrusion  21  and the first dielectric layer  12  can be formed by the same or different materials. Besides, the protrusion  21  and the first dielectric layer  12  can be formed in the same manufacturing process or separate processes. Moreover, the shape of the protrusion  21  can be semi-circular, polygonal or other shapes, and the invention is not limited thereto. Furthermore, the protrusions  21  can have the same or different heights. 
         [0023]    The metal layer  9  is formed on the second substrate  17 . The protection layer  10  is formed on the metal layer  9  in the transistor area  1   a,  and is formed on the second substrate  17  in the non-transistor area  1   b  and the opening area  1   c.  The liquid crystal layer  13  is formed on the first dielectric layer  12  and located between the first substrate  16  and the second substrate  17 . The liquid crystal layer  13  is driven by such as a horizontal electrical field or a vertical electrical field. When the liquid crystal layer  13  is driven by the vertical electrical field, the first substrate  16  can have an electrode layer (not illustrated). The electrode layer, composed of such as full electrodes or patterned electrodes, is formed by a transparent material whose transmittance is above 90%. The liquid crystal layer  13  is formed by a liquid crystal material with a second permittivity. The liquid crystal material is such as a blue phase liquid crystal, other liquid crystal with high polar functional group, or a liquid crystal containing a high proportion of chiral material. The second permittivity ε 2  is such as an average permittivity. The liquid crystal is formed by a dielectric anisotropic material whose average permittivity is expressed as the second permittivity 
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         [0000]    The permittivity ε //  represents a permittivity of a long axis of liquid crystal. The permittivity ε ⊥  represents a permittivity of a short axis of liquid crystal. The liquid crystal layer  13  has the second permittivity ε 2  greater than the first permittivity ε 1 . The second permittivity ε 2  is greater than or equal to 20 and less than or equal to 500. The ratio of the second permittivity ε 2  to the first permittivity ε 1  is greater than or equal to 5 and less than or equal to 100. 
         [0024]    Referring to  FIG. 2 .  FIG. 2  illustrates a relationship of transmittance vs. voltage as a voltage Vd is applied to a liquid crystal layer  13  via a data line. In the present embodiment, the average permittivity of the liquid crystal layer  13  is about 100, and the permittivity of the first dielectric layer  12  is about 5. The Vth is a threshold voltage when the transmittance of the liquid crystal layer  13  is about 0.1% and more than 0%. When the liquid crystal layer reaches a maximum transmittance, the voltage Vd driving the liquid crystal layer is defined as Vac. In the present embodiment, the threshold voltage Vth and the driving voltage Vd satisfy the condition: 
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         [0025]    Referring to  FIG. 1  again. The pixel electrode  14  neighbors with the signal line  11 . The pixel electrode  14  is closer to the signal line  11  than the pixel electrode  14 ′ is. The voltages at the pixel electrode  14  and the pixel electrode  14 ′ can have the same or different electrical potentials. For instance, the pixel electrode  14 ′ is a common voltage, but the pixel electrode  14  is not a common voltage. As indicated in  FIG. 1 , in comparison to the pixel electrode  14 ′, the pixel electrode  14  is the pixel electrode closest to the signal line  11 . The distance between the signal line  11  and a side of the first dielectric layer  12  is d 1 , and the distance between the side of the first dielectric layer  12  and the side of the pixel electrode  14  is d 2 . The distance d 1  is greater than or equal to 1 μm and less than or equal to 20 μm. The distance between the first dielectric layer  12  and the pixel electrode  14  via the liquid crystal layer  13  is d 2 . The distance d 2  is greater than or equal to 1 μm and less than or equal to 20 μm. A sum of the distance d 1  and the distance d 2  is greater than or equal to 2 μm and less than or equal to 20 μm. The distance d 1  and the distance d 2  can be calculated in many different ways. For convenience of elaboration, as indicated in  FIG. 1 , the distance between a central point of the height of a side of the signal line  11  and a central point of the height of the side of the first dielectric layer  12  is d 1 , and the distance between a central point of the height of the side of the first dielectric layer  12  and a central point of the height of the side of the pixel electrode  14  is d 2 . 
         [0026]    The first parasitic capacitance Cgd 1  is formed between the signal line  11  and the side of the first dielectric layer  12 , and the second parasitic capacitance Cgd 2  is formed between the side of the first dielectric layer  12  and the side of the pixel electrode  14 . The first permittivity ε 1 , the second permittivity ε 2 , the first distance d 1 , the second distance d 2 , the threshold voltage Vth and the voltage Vd must satisfy the condition 
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         [0000]    When the condition of Equation 1 is conformed, the transmittance of the region between the signal line  11  and the side of the pixel electrode  14  is less than 0.1% and more than 0%. The Vd is a driving voltage Vac making the LCD panel  1  reach the maximum transmittance ( FIG. 2 ) if the signal line  11  is a data line, and is a voltage difference between VGL and the pixel electrode if the signal line  11  is a scan line. The voltage VGL is a gate low voltage of the scan line. 
         [0027]    When a voltage difference is formed between the signal line and the pixel electrode, the distribution of voltage difference is dependent on the permittivity of each material layer between the signal line and the pixel electrode. In the present embodiment, since the second permittivity ε 2  is greater than the first permittivity ε 1 , the capacitance of the second parasitic capacitance Cgd 2  is greater than the capacitance of the first parasitic capacitance Cgd 1 , and the voltage difference between two ends of the second parasitic capacitance Cgd 2  is far less than the voltage difference between two ends of the first parasitic capacitance Cgd 1 . This implies that when a voltage difference is formed between the signal line and the pixel electrode, the voltage difference of the second parasitic capacitance Cgd 2  will be very small. When the voltage difference between two ends of the second parasitic capacitance Cgd 2  is less than the threshold voltage Vth driving the liquid crystal layer  13 , the liquid crystal in the non-transistor area  1   b  will not be driven. Particularly, the liquid crystal layer in a region between a side of the TFT  15  and the side of the pixel electrode  14  closest to the signal line  11  will not be driven, so the light will not be leaked via the liquid crystal layer, and the transmittance of the non-transistor area  1   b  is less than 0.1% and more than 0%. That is, the liquid crystal layer in the said area does not generate light leakage, so the black matrix  18  only needs to be disposed in the transistor area  1   a  and does not need to be extended to the non-transistor area  1   b.  Since the disposition of the black matrix  18  has to consider alignment error, an area for alignment error needs to be added to the disposition area, hence affecting aperture ratio. In the present embodiment, since the black matrix  18  only needs to be disposed in the transistor area  1   a,  the transistor area  1   a  is less than the non-opening area. Thus, the disposition area of the black matrix  18  can be smaller, not only saving material but also reducing manufacturing cost. Moreover, the non-transistor area  1   b  neighbors with the transistor area  1   a,  and the non-transistor area  1   b  does not belong to the opening area. The disposition area having considered alignment error is still within the non-transistor area  1   b  and will not affect the opening area, and aperture ratio can thus be enhanced. 
         [0028]    When the LCD panel  1  does not comprise the polarizer  22  and the polarizer  23 , there will be no gray level frames for bright state and dark state. Meanwhile, the light can pass through any areas not having a metal trace or a black matrix, and even the color filter allows the light with specific waveband to pass through. Conversely, when the LCD panel  1  comprises the polarizer  22  and the polarizer  23 , the polarized light is easily affected by the liquid crystal layer  13  and generates gray level frames for bright state and dark state. Only under such circumstances will there be transmittance changes. The area with the black matrix  18  is impermeable to the light. That is, the transmittance of the area shielded by the black matrix  18  is near 0%. In the area without the black matrix  18  or not shielded by metal traces, each layer on the optical path has high transparency, and the transmittance is mainly dependent on the liquid crystal layer  13 . 
         [0029]    In the non-transistor area  1   b  without the black matrix  18 , only the part with the signal line  11  is impermeable to the light due to the metal layer shielding the light, and the remaining parts on the optical path are transparent material layers. Therefore, with the use of the polarizer  22  and the polarizer  23 , the transmittance of the non-transistor area  1   b  not shielded by the black matrix  18  is mainly dependent on the liquid crystal layer  13 . When the condition of Equation  1  is conformed, the transmittance is less than 0.1% and more than 0%. That is, the light will not be leaked via the liquid crystal layer  13  in the non-transistor area  1   b.    
         [0030]    As indicated in  FIG. 1 , the pixel electrode  14  is formed on the protrusion  21  and goes deep into the liquid crystal layer. Thus, the electrical field can penetrate into the liquid crystal layer  13  to enhance the driving effect. However, practical application is not limited thereto. In other implementations, the pixel electrode  14  may not formed on the protrusion  21 . In addition, the black matrix  18  of  FIG. 1  neighbors with the underneath of the first substrate  16 . However, practical application is not limited thereto. In other implementations, the black matrix  18  may be formed on the TFT  15  and encapsulate the TFT  15 . 
       First Embodiment 
       [0031]    Referring to  FIG. 1  and  FIG. 3  at the same time,  FIG. 3  is a cross-sectional view of according to a first embodiment an LCD panel. In the first embodiment, the LCD panel  1  is exemplified by an LCD panel  1 ( 1 ), and the first dielectric layer  12  is exemplified by an insulating layer  12   a.  The LCD panel  1 ( 1 ) further comprises a color filter  19 , and the insulating layer  12   a  encapsulates the signal line  11  and the TFT  15 . The liquid crystal layer  13  is formed on the insulating layer  12   a.  The color filter  19  is formed on the liquid crystal layer  13 . The black matrix  18  is formed on the color filter  19  in the transistor area  1   a.  When the above condition is conformed, the light will not be leaked via the non-transistor area  1   b,  that is, the liquid crystal layer in the region between the side of the TFT  15  and the side of the pixel electrode  14  closest to the signal line  11  will be free of light leakage. The transmittance of the non-transistor area  1   b  is less than 0.1% and more than 0%. 
       Second Embodiment 
       [0032]    Referring to  FIG. 1  and  FIG. 4  at the same time.  FIG. 4  is a cross-sectional view of according to a second embodiment an LCD panel. In the second embodiment, the LCD panel  1  is exemplified by an LCD panel  1 ( 2 ), and the first dielectric layer  12  is exemplified by a color filter  12   b.  The second embodiment and the first embodiment are different mainly in that the LCD panel  1 ( 2 ) adopts a color filter on array (COA) having a color filter. That is, the color filter  12   b  is formed above the TFT  15 . The LCD panel  1 ( 2 ) further comprises a planarization layer  20 , and the color filter  12   b  encapsulates the signal line  11  and the TFT  15 . The liquid crystal layer  13  is formed on the color filter  12   b.  The planarization layer  20  is formed on the liquid crystal layer  13 . The black matrix  18  is formed on the planarization layer  20  in the transistor area  1   a.    
         [0033]    In the second embodiment, the first dielectric layer is realized by the color filter  12   b,  and has a first permittivity ε 1 . As indicated in  FIG. 4 , the distance between the central point of the height of the side of the signal line  11  and the central point of the height of the side of the pixel electrode  14  is defined as d 1 +d 2 . The distance between the central point of the height of the side of the signal line  11  and the central point of the height of a side of the color filter  12   b  is a first distance d 1 , and the distance between the central point of the height of the side of the color filter  12   b  and the central point of the height of the side of the pixel electrode  14  is a second distance d 2 . 
         [0034]    The first parasitic capacitance Cgd 1  is formed between the side of the signal line  11  and the side of the color filter  12   b,  and the second parasitic capacitance Cgd 2  is formed between the side of the pixel electrode  14  and the side of the color filter  12   b.  In the second embodiment, the first permittivity ε 1  of the color filter  12   b,  the average permittivity of the liquid crystal layer is the second permittivity ε 2 , the distance d 1 , the distance d 2 , the threshold voltage Vth and the voltage Vd must satisfy the condition 
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         [0035]    When a voltage difference is formed between the signal line and the pixel electrode, the distribution of voltage difference is dependent on the permittivity of each material layer between the signal line and the pixel electrode. In the present embodiment, when the condition 
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         [0000]    is conformed, the second permittivity ε 2  is greater than the first permittivity ε 1 , and the capacitance of the second parasitic capacitance Cgd 2  is greater than the capacitance of the first parasitic capacitance Cgd 1 . This implies that the voltage difference of the second parasitic capacitance Cgd 2  will be very small. When the voltage difference between two ends of the second parasitic capacitance Cgd 2  is less than the threshold voltage Vth driving the liquid crystal layer  13 , the liquid crystal in the non-transistor area  1   b  will not be driven, so the light will not be leaked via the liquid crystal layer, and the transmittance of the non-transistor area  1   b  is less than 0.1% and more than 0%. Therefore, the black matrix  18  only needs to be disposed in the transistor area  1   a  and does not need to be extended to the non-transistor area  1   b.  Thus, the disposition area of the black matrix  18  can be smaller, not only saving material but also reducing manufacturing cost. The disposition area having considered alignment error is still within the non-transistor area  1   b  and will not affect the opening area, and aperture ratio can thus be enhanced. 
       Third Embodiment 
       [0036]    Referring to  FIG. 1  and  FIG. 5  at the same time,  FIG. 5  is a cross-sectional view of according to a third embodiment an LCD panel. In the third embodiment, the first dielectric layer  12  is exemplified by an insulating layer  12   c  and the color filter  12   b.  The third embodiment and the second embodiment are different mainly in that the first dielectric layer of the LCD panel  1 ( 3 ) further comprises an insulating layer  12   c  formed on a part of the color filter  12   b.  With the above conditions being conformed, the transmittance of the non-transistor area  1   b  is less than 0.1% and more than 0%, and the light will not be leaked via the non-transistor area  1   b,  particularly the liquid crystal layer in a region between the side of the signal line  11  and the side of the pixel electrode  14  closest to the signal line  11 . 
       Fourth Embodiment 
       [0037]    Referring to  FIG. 1  and  FIG. 6  at the same time.  FIG. 6  is a cross-sectional view of according to a fourth embodiment an LCD panel. In the fourth embodiment, the LCD panel  1  is exemplified by an LCD panel  1 ( 4 ). The fourth embodiment and the second embodiment are different mainly in that the LCD panel  1 ( 4 ) adopts a black matrix on array (BOA). That is, the black matrix  18  is formed above the TFT  15 . In the fourth embodiment, the black matrix  18  is located between the color filter  12   b  and the TFT  15 . In other embodiments, the black matrix  18  may be located above the color filter  12   b  (not illustrated). With the above conditions being conformed, the light will not be leaked via the non-transistor area  1   b,  particularly the liquid crystal layer in a region between the side of the signal line  11  and the side of the pixel electrode  14  closest to the signal line  11 , and the transmittance of the non-transistor area  1   b  is less than 0.1% and more than 0%. 
       Fifth Embodiment 
       [0038]    Referring to  FIG. 1  and  FIG. 7  at the same time,  FIG. 7  is a cross-sectional view of according to a fifth embodiment an LCD panel. In the fifth embodiment, the LCD panel  1  is exemplified by an LCD panel  1 ( 5 ). In the fourth embodiment, the first dielectric layer  12  is exemplified by the insulating layer  12   c  and the color filter  12   b.  The fifth embodiment and the fourth embodiment are different mainly in that the first dielectric layer of the LCD panel  1 ( 5 ) further comprises the insulating layer  12   c  formed on a part of the color filter  12   b.  The insulating layer  12   c  and the pixel electrode  14  can be the same or different layers. With the above conditions being conformed, the light will not be leaked via the non-transistor area  1   b,  particularly the liquid crystal layer in a region between the side of the signal line  11  and the side of the pixel electrode  14  closest to the signal line  11 , and the transmittance of the non-transistor area  1   b  is less than 0.1% and more than 0%. 
       Sixth Embodiment 
       [0039]    Referring to  FIG. 1  and  FIG. 8  at the same time,  FIG. 8  is a cross-sectional view of according to a sixth embodiment an LCD panel. In the sixth embodiment, the LCD panel  1  is exemplified by an LCD panel  1 ( 6 ), and the first dielectric layer  12  is exemplified by the insulating layer  12   a.  The sixth embodiment and the fourth embodiment are different mainly in that the first dielectric layer of the LCD panel  1 ( 6 ) is realized by the insulating layer  12   a,  not the color filter. In other embodiments, the black matrix  18  can be located above the insulating layer  12   a  (not illustrated). With the above conditions being conformed, the light will not be leaked via the non-transistor area  1   b,  particularly the liquid crystal layer in a region between the side of the signal line  11  and the side of the pixel electrode  14  closest to the signal line  11 , and the transmittance of the non-transistor area  1   b  is less than 0.1% and more than 0%. 
         [0040]    Since the permittivity of the first dielectric layer of the LCD panel is far less than the average permittivity of the liquid crystal layer, the parasitic capacitance formed by the first dielectric layer is smaller than the parasitic capacitance formed by the liquid crystal layer. Thus, the most of the parasitic capacitance is distributed in the first dielectric layer. That is, the voltage difference of the parasitic capacitance in a region between the side of the signal line  11  and the side of the pixel electrode  14  closest to the signal line  11  is very small and less than the threshold voltage Vth. Thus, the transmittance is less than 0.1% and more than 0%, and the light will not be leaked via the non-transistor area  1   b,  particularly the liquid crystal layer in a region between the side of the signal line  11  and the side of the pixel electrode  14  closest to the signal line  11 . Since the black matrix does not need to be extended to the non-transistor area from the transistor area, and the consideration of alignment error does not affect the opening area, manufacturing cost is reduced and aperture ratio is increased. 
         [0041]    While the invention has been described by way of example and in terms of the preferred embodiment(s), it is to be understood that the invention is not limited thereto. On the contrary, it is intended to cover various modifications and similar arrangements and procedures, and the scope of the appended claims therefore should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements and procedures.