Patent Publication Number: US-11662633-B2

Title: Display panel

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a Divisional Application (DA) of U.S. Ser. No. 17/038,860, filed on Sep. 30, 2020, which is a Divisional Application (DA) of U.S. Ser. No. 16/510,159, filed on Jul. 12, 2019, which is a Divisional Application (DA) of U.S. Ser. No. 15/645,471, filed on Jul. 10, 2017, which is a continuation application (CA) of U.S. Ser. No. 14/729,661, filed on Jun. 3, 2015, which claims priority under 35 U.S.C. § 119(a) on Patent Application No(s). 103122681, filed in Taiwan, Republic of China on Jul. 1, 2014, the entire contents of which are hereby incorporated by reference. 
    
    
     BACKGROUND 
     Field of Invention 
     The disclosure relates to a display panel. 
     Related Art 
     The display panel is popularized and matured in technology nowadays, and recently the development direction thereof is towards the higher resolution, lower power consumption and larger size. One of the factors that affects the resolution is the uneven surface of the color filter material, which will cause a reduced transmittance. Furthermore, the above factor will also become more prominent when the pixel size is getting smaller and smaller (i.e. the smaller interval of the black matrix). 
       FIG.  1 A  is a schematic enlarged diagram of a second substrate of a conventional display panel, and  FIG.  1 B  is a schematic enlarged diagram of the region A 1  in  FIG.  1 A . 
     As shown in  FIGS.  1 A and  1 B , the conventional display panel at least includes a first substrate (not shown), a display medium (not shown), a second substrate S 2 , a black matrix B and a color filter material C. The color filter material C is disposed between the black matrix B by corresponding to each of the pixel areas (not shown). It is clear from the figure that the color filter material C has a height difference at the overlap of the color filter material C and the black matrix B, and the height difference at the overlap of the color filter material C and the black matrix B will result in the scattered light. Therefore, if the height difference at the overlap of the color filter material C and the black matrix B has a larger proportion of the color filter material C, the transmittance will be reduced more. 
     By taking a full HD product as an example, the ratio of the flat portion to bulge portion is about 86/14 for the portion of the color filter material C corresponding to a single sub-pixel. Moreover, for the WQHD product having a higher resolution and a smaller sub-pixel than the full HD product, the ratio of the flat portion to the bulge portion for the portion of the color filter material C corresponding to a single sub-pixel will be reduced to 82/18. Furthermore, for the recently developed 4K2K product of high resolution, the ratio of the flat portion to the bulge portion for the portion of the color filter material C corresponding to a single sub-pixel will be even reduced to 72/28. 
     So, due to the increased resolution and less size of sub-pixel, the bulge C 1  of the color filter material C at the vicinity to the black matrix B will become more significant for the transmittance. 
     In addition to the above problem, the smaller sub-pixel (smaller interval of the black matrix) also will cause the developer solution to be easily left between the black matrixes during the process, and therefore the photoresist will be hard to be completely clean and the carbon will be left. This problem also affects the transmittance of the display panel. 
     Therefore, it is an important subject to provide a display panel with the black matrix structure which can achieve a higher transmittance, when applied to a high-resolution product, and a reduced amount of the carbon remaining between the black matrixes during the process. 
     SUMMARY 
     An objective of the disclosure is to provide a display panel which can achieve a higher transmittance, when applied to a high-resolution product, and a reduced amount of the carbon remaining between the black matrixes during the process. 
     To achieve the above objective, a display panel according to the disclosure comprises a first substrate, a second substrate and a black matrix disposed between the first substrate and the second substrate. 
     The first substrate includes a plurality of pixel areas arranged in a matrix, and each of the pixel areas has a plurality of sub-pixel areas. The second substrate is disposed on the first substrate. 
     The black matrix comprises a plurality of row shading bars and a plurality of column shading bars. The row shading bars are disposed between the two adjacent pixel areas and extend along a first direction, and at least one of the row shading bars has a first thickness. The column shading bars are disposed between the two adjacent sub-pixel areas and extend along a second direction, and at least one of the column shading bars has a second thickness. The second thickness is different from the first thickness and the first direction is different from the second direction. 
     In one embodiment, the second thickness is less than the first thickness. 
     In one embodiment, the row shading bars are connected to at least a part of the column shading bars. 
     In one embodiment, the column shading bars disposed between the two adjacent row shading bars are separated from the two adjacent row shading bars. 
     In one embodiment, the column shading bars disposed between the two adjacent row shading bars are connected to one of the two adjacent row shading bars. 
     In one embodiment, the widths of the column shading bars along the first direction are varied along the second direction. 
     In one embodiment, the second thicknesses of the column shading bars are varied along the second direction. 
     In one embodiment, the column shading bars include a first column shading bar and a second column shading bar, the first column shading bar has a third thickness, the second column shading bar has a fourth thickness, and the third thickness is greater than the fourth thickness, and the third thickness of the first column shading bar is less than or equal to the first thickness of the row shading bar. 
     In one embodiment, the first thickness is between 1.2 μm and 2.0 μm. 
     In one embodiment, the second thickness is between 0.5 μm and 1.0 μm. 
     In one embodiment, the display panel further comprises a plurality of color filter blocks, each of which is disposed between the two adjacent column shading bars. 
     In one embodiment, an end of one of the column shading bars disposed between the two adjacent row shading bars is connected to one of the two adjacent row shading bars, and another end of the one of column shading bars is separated from the other one of the two adjacent row shading bars. 
     In one embodiment, two ends of one of the column shading bars disposed between the two adjacent row shading bars are connected to the two adjacent row shading bars, and the width of the two ends of the one of the column shading bars are less than the width of a central part of the one of the column shading bars. 
     In one embodiment, the column shading bars include a third column shading bar and a fourth column shading bar disposed between the two adjacent row shading bars, the third column shading bar is adjacent to the fourth shading bar, the third column shading bar is separated from one of the two adjacent row shading bars, and the fourth column shading bar is separated from the other one of the two adjacent row shading bars. 
     In one embodiment, the adjacent two first column shading bars are disposed on the opposite sides of one of the sub-pixel areas. 
     As mentioned above, this disclosure adjusts the thickness, shape and layout of the column shading bars of the black matrix to make the pixel areas evener. Thereby, the developer solution or carbon will be not easily left in the pixel areas during the process, and the remaining photoresist problem can be reduced. Therefore, the transmittance of the high-resolution product can be enhanced. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The disclosure will become more fully understood from the detailed description and accompanying drawings, which are given for illustration only, and thus are not limitative of the present disclosure, and wherein: 
         FIG.  1 A  is a schematic enlarged diagram of a second substrate of a conventional display panel; 
         FIG.  1 B  is a schematic enlarged diagram of the region A 1  in  FIG.  1 A ; 
         FIG.  2 A  is a schematic exploded diagram of a display panel of an embodiment of the disclosure; 
         FIG.  2 B  is a schematic enlarged diagram of the first substrate in  FIG.  2 A ; 
         FIG.  3    is a schematic partial enlarged diagram of the color filter block and the black matrix in  FIG.  2 A  according to the first embodiment of the disclosure; 
         FIG.  4 A  is a schematic partial enlarged diagram of the second substrate of the display panel of this embodiment; 
         FIG.  4 B  is a schematic enlarged diagram of the region A 2  in  FIG.  4 A ; 
         FIG.  5 A  is a schematic diagram of the black matrix according to the second embodiment of the disclosure; 
         FIG.  5 B  is a schematic top-view diagram of the black matrix according to the second embodiment of the disclosure; 
         FIG.  6    is a schematic top-view diagram of the black matrix according to the third embodiment of the disclosure; 
         FIG.  7    is a schematic top-view diagram of the black matrix according to the fourth embodiment of the disclosure; 
         FIG.  8    is a schematic top-view diagram of the black matrix according to the fifth embodiments of the disclosure; 
         FIG.  9    is a schematic top-view diagram of the black matrix according to the sixth embodiments of the disclosure; 
         FIG.  10    is a schematic top-view diagram of the black matrix according to the seventh embodiments of the disclosure; 
         FIG.  11    is a schematic diagram of the black matrix of the eighth embodiment of the disclosure; and 
         FIG.  12    is a schematic diagram of the black matrix of the ninth embodiment of the disclosure. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present disclosure will be apparent from the following detailed description, which proceeds with reference to the accompanying drawings, wherein the same references relate to the same elements. 
     To be noted, the following embodiments shown in the figures are just for the illustrative purpose but not for representing the actual dimensions and size relation. 
     As shown in  FIGS.  2 A and  2 B , a display panel  1  can at least include a first substrate  100 , a second substrate  120  and a black matrix  130 . The display panel  1  can further include a display medium  110  disposed between the first substrate  100  and the second substrate  120 . The display medium  110  can be liquid crystal material, plasma material or organic electroluminescent material for example. Therefore, with different types of the display medium  110 , the display panel  1  can be a liquid crystal display panel, plasma display panel or organic light emitting display panel. The liquid crystal display panel will be taken as an example in the following embodiments, but those skilled in the art can analogize other display panels. 
     The first substrate  100  can be an active array substrate, but this disclosure is not limited thereto. The first substrate  100  includes a plurality of scan lines  100   a  and a plurality of data lines  100   b  which cross each other. The scan lines  100   a  and the data lines  100   b  are substantially perpendicular to each other to define a pixel matrix  101  including a plurality of pixel areas  1012 . The pixel areas  1012  are arranged in a matrix, and each of the pixel area  1012  has a plurality of sub-pixel areas  1012   a ,  1012   b ,  1012   c . In other words, in this embodiment, the sub-pixel areas  1012   a ,  1012   b ,  1012   c  can form a pixel area  1012 . 
     Besides, those skilled in the art can comprehend that the patterned conductive layer includes a plurality of thin film transistors  100   c  and a plurality of pixel electrodes  100   d.    
     The second substrate  120  is disposed on the first substrate  100 . Herein, the second substrate  120  and the first substrate  100  are disposed oppositely, and that is, the second substrate  120  is disposed on the opposite side of the first substrate  100 . 
     The first substrate  100  or second substrate  120  of this embodiment can be made by glass, quartz, organic polymer or other applicable material. 
     Besides, the display panel  1  can further include an electrode layer  111 . The liquid crystal molecules of the display medium  110  can be driven by the electric field formed by the electrode layer  111  and the pixel matrix  101  to achieve different display effects. 
     The black matrix  130  is disposed between the first substrate  100  and the second substrate  120 . Furthermore, the black matrix  130  is disposed between the second substrate  120  and the display medium  110 . The black matrix  130  includes a plurality of row shading bars  131  and a plurality of column shading bars  132 . Each of the row shading bars  131  is disposed corresponding to the position between the two adjacent rows of the pixel areas  1012 , and for example, corresponding to the scan line  100   a  of the first substrate  100 . The column shading bars  132  are disposed between the two adjacent row shading bars  131  and disposed corresponding to the position between the two adjacent sub-pixel areas  1012   a ,  1012   b ,  1012   c . For example, some of the column shading bars  132  are disposed corresponding to the data lines  100   b  of the first substrate  100 . Moreover, the scan lines  100   a  and the data lines  100   b  of the first substrate  100  cross each other and are substantially perpendicular to each other. 
     The black matrix  130  is made by black resin and formed into a grid structure for shading the light. The black matrix  130  can be disposed corresponding to the pixel matrix  101 , and each of the meshes of the grid structure of the black matrix  130  is disposed corresponding to a pixel area or sub-pixel area of the first substrate  100 . The detailed structure of the black matrix  130  will be illustrated later. 
     The display panel  1  of this embodiment can further include the color filter blocks  114  disposed between the display medium  110  and the second substrate  120 . The color filter blocks  114  are disposed corresponding to the pixel areas  1012 . The color filter blocks  114  can be the combination of red color filter blocks, green color filter blocks and blue color filter blocks. In other embodiments, the color filter blocks  114  may have another colorful combination, as long as the full color display effect can be achieved. 
     The structure of the black matrix layer is illustrated below. 
       FIG.  3    is a schematic partial enlarged diagram of the color filter block and the black matrix in  FIG.  2 A  according to the first embodiment of the disclosure,  FIG.  4 A  is a schematic partial enlarged diagram of the second substrate of the display panel of this embodiment, and  FIG.  4 B  is a schematic enlarged diagram of the region A 2  in  FIG.  4 A . 
     As shown in  FIGS.  3 ,  4 A,  4 B , the black matrix  130  can be applied to the display panel and includes a plurality of row shading bars  131  and a plurality of column shading bars  132 . The row shading bars  131  connect to the column shading bars  132  correspondingly. Each of the column shading bars  132  is disposed between the two adjacent row shading bars  131 , and two ends of the column shading bar  132  connect to the two adjacent row shading bars  131 . 
     The row shading bars  131  extend towards the X direction (the first direction) and has a first thickness h 1 . Each of the row shading bars  131  is disposed corresponding to the position between the two adjacent rows of the pixel areas of the pixel matrix (not shown). 
     The column shading bars  132  extend towards the Y direction (the second direction) and has a second thickness h 2 . Each of the column shading bars  132  is disposed corresponding to the position between the two adjacent sub-pixel areas. The second thickness h 2  is different from the first thickness h 1 . In this embodiment, the second thickness h 2  is less than the first thickness h 1 , and the X direction (the first direction) and the Y direction (the second direction) are substantially perpendicular to each other. In this embodiment, the first direction is different from the second direction. 
     Furthermore, the row shading bars  131  of this embodiment are disposed corresponding to the scan lines of the first substrate  100 , and the column shading bars  132  are disposed corresponding to the data lines of the first substrate  100 . Besides, the scan lines and data lines of the first substrate  100  cross each other. 
     In this embodiment, the first thickness h 1  of the row shading bar  131  can be between 1.2 μm and 2.0 μm, and the second thickness h 2  of the column shading bar  132  can be between 0.5 μm and 1.0 μm. 
     In other words, the second thickness h 2  of the column shading bar  132  can be adjusted in this embodiment so as to be less than the first thickness h 1 , and therefore when the color filter blocks  114  are disposed on the black matrix  130 , the overlap  114   b  of the color filter blocks  114  and the black matrix  130  will have a less proportion than the flat portion  114   a  of the color filter block  114  corresponding to a single pixel area (sub-pixel area). Hence, the surface of the color filter block  114  will be more even (also referring to  FIG.  1 B ). Thereby, the light will be less scattered and shifted when passing through the color filter blocks  114  so that the transmittance of the display panel can be enhanced. 
     In this embodiment, the row shading bar  131  and column shading bar  132  of the black matrix  130  can be formed with two different thicknesses by the halftone mask or optical proximity correction (OPC) mask. 
     Moreover, this embodiment only adjusts the second thickness h 2  of the column shading bar  132 , so that the light shading ability of the row shading bar  131  and column shading bar  132  won&#39;t be affected and the entire optical density also won&#39;t be affected. Therefore, the entire contrast also won&#39;t be affected. 
     Then, refer to  FIGS.  5 A and  5 B , which are schematic perspective and top-view diagrams of the black matrix according to the second embodiment of the disclosure. 
     Like the first embodiment of  FIG.  3   , the black matrix  230  of this embodiment includes a plurality of row shading bars  231  and a plurality of column shading bars  232 . The row shading bars  231  have a first thickness h 1 . The column shading bars  232  have a second thickness h 2 . The second thickness h 2  is less than the first thickness h 1 . 
     The main difference from the above embodiment is that each of the column shading bars  232  disposed between the two adjacent row shading bars  231  is connected to one of the two adjacent row shading bars  231 . In other words, one end of the column shading bar  232  is connected to one of the adjacent row shading bars  231 , but the other end is separated from the other adjacent row shading bar  231 . In this embodiment, the connection of the two adjacent row shading bars  231  and the column shading bars  232  is implemented in an alternate manner. The column shading bars  232  include a third column shading bar and a fourth column shading bar disposed between the two adjacent row shading bars  231 , the third column shading bar is adjacent to the fourth shading bar, the third column shading bar is separated from one of the two adjacent row shading bars  231 , and the fourth column shading bar is separated from the other one of the two adjacent row shading bars  231 . For example, the odd-numbered column shading bars  232  are connected to one of the two adjacent row shading bars  231 , and the even-numbered column shading bars  232  are connected to the other one of the two adjacent row shading bars  231 . 
     As shown in  FIG.  5 B , a gap G is formed between the column shading bar  232  and the row shading bars  231 , and can be between 0.5 μm and 5.0 μm according to different requirements. The gap G of this embodiment is 3.0 μm, but this disclosure is not limited thereto. 
     The advantage of this embodiment is that the flow guiding channels can be formed during the process to allow the developer solution to flow out easily, so that the remaining carbon and photoresist will be avoided and the transmittance of the display panel can be thus enhanced. 
     The disposition and effect of other elements can be comprehended by referring to the above embodiment and therefore are not described here for conciseness. 
       FIGS.  6  and  7    are schematic top-view diagrams of the black matrix according to the third embodiment and fourth embodiment of the disclosure. 
     Like the second embodiment, the black matrix  330  of the third embodiment includes a plurality of row shading bars  331  and a plurality of column shading bars  332 . The row shading bars  331  have a first thickness (not shown). The column shading bars  332  have a second thickness (not shown). The second thickness is less than the first thickness. Moreover, the row shading bars  331  of this embodiment are connected to a part of the column shading bars  332 , and that is, one end of the column shading bar  332  is connected to the row shading bar  331  but the other end is separate from the other row shading bars  331 . 
     The main difference from the second embodiment is that the column shading bars  332  disposed between the two adjacent row shading bars  331  are connected to one of the two adjacent row shading bars  331  at the same side and are separated from the other one of the two adjacent row shading bars  331  at the other side, so that the gaps G are formed on the same side. 
     The black matrix  430  of the fourth embodiment also includes a plurality of row shading bars  431  and a plurality of column shading bars  432 . The row shading bars  431  have a first thickness (not shown). The column shading bars  432  have a second thickness (not shown). The second thickness is less than the first thickness. 
     The main difference from the second and third embodiments is that the column shading bars  432  disposed between the two adjacent row shading bars  431  are separated from the two adjacent row shading bars  431 . 
     The disposition and effect of other elements can be comprehended by referring to the above embodiments and therefore are not described here for conciseness. 
       FIGS.  8  to  10    are schematic top-view diagrams of the black matrix according to the fifth, sixth and seventh embodiments of the disclosure. 
     Refer to the fifth embodiment shown in  FIG.  8   . Like the first embodiment in  FIG.  3   , the black matrix  530  of the this embodiment includes a plurality of row shading bars  531  and a plurality of column shading bars  532 . The row shading bars  531  have a first thickness (not shown). The column shading bars  532  have a second thickness (not shown). The second thickness is less than the first thickness. 
     The main difference from the first embodiment is that the two ends of the column shading bars  532  disposed between the two adjacent row shading bars  531  are connected to the two adjacent row shading bars  531 , and the width w of the column shading bars  532  varies along the Y direction (the second direction). Herein for example, the width of the two ends of the one of the column shading bars  532  are less than the width of a central part of the one of the column shading bars  532 . In detail, the two ends of the column shading bar  532  at the vicinity to the row shading bars  531  have a narrower width, so that the developer solution can flow out more easily. Therefore, the remaining carbon and photoresist will be reduced or avoided and the transmittance of the display panel can be thus enhanced. 
     Then, refer to the sixth embodiment of  FIG.  9   . Like the fifth embodiment, the black matrix  630  of the this embodiment includes a plurality of row shading bars  631  and a plurality of column shading bars  632 . The row shading bars  631  have a first thickness (not shown). The column shading bars  632  have a second thickness (not shown). The second thickness is less than the first thickness. 
     The main difference from the fifth embodiment is that only one end of the column shading bar  632  of this embodiment at the vicinity to the row shading bar  631  has a narrower width. Besides, the narrower ends of the column shading bars  632  are disposed in an alternate manner. 
     Then, refer to the seventh embodiment of  FIG.  10   . Like the fifth embodiment, the black matrix  730  of the this embodiment includes a plurality of row shading bars  731  and a plurality of column shading bars  732 . The row shading bars  731  have a first thickness (not shown). The column shading bars  732  have a second thickness (not shown). The second thickness is less than the first thickness. 
     The main difference from the fifth embodiment is that only one end of the column shading bar  732  of this embodiment at the vicinity to the row shading bar  731  has a narrower width. Besides, the narrower ends of the column shading bars  732  are disposed at the same side. 
     The disposition and effect of other elements can be comprehended by referring to the above embodiments and therefore are not described here for conciseness. 
       FIG.  11    is a schematic diagram of the black matrix of the eighth embodiment of the disclosure. 
     As shown in  FIG.  11   , like the first embodiment of  FIG.  3   , the black matrix  830  of the this embodiment includes a plurality of row shading bars  831  and a plurality of column shading bars  832 . The main difference from the first embodiment is that the row shading bars  831  have a first thickness, and the column shading bars  832  have different thicknesses which are less than or equal to the thickness of the row shading bars  831 . 
     In this embodiment, the row shading bars  831  have a first thickness h 1 . The column shading bars  832  include a first column shading bar  832   a  and a second column shading bar  832   b . The first column shading bar  832   a  has a third thickness h 3 , and the second column shading bar  832   b  has a fourth thickness h 4 . The third thickness h 3  is greater than the fourth thickness h 4 , and is less than or equal to the first thickness h 1 . 
     The first column shading bar  832   a  and the second column shading bar  832   b  are disposed corresponding to the positions between the adjacent sub-pixel areas  1012   a ,  1012   b ,  1012   c . The above disposition has an advantage of reducing the optical interference between the unit pixels  1012 . 
     In order to help understanding the relative positions of the pixel areas  1012 , sub-pixel areas  1012   a ,  1012   b , or  1012   c , row shading bars  831  and column shading bars  832 , the positions of the pixel area  1012  and sub-pixel areas  1012   a ,  1012   b ,  1012   c  are marked by the dotted line. 
     In this embodiment, the first column shading bar  832   a  is disposed between the two adjacent row shading bars  831  and between the two adjacent pixel areas  1012 . The second column shading bars  832   b  are disposed between the two first column shading bars  832   a  and between the two adjacent sub-pixel areas  1012   a ,  1012   b , or  1012   c . In this embodiment, the color mix problem between the pixel areas  1012  can be avoided by the disposition of the first column shading bars  832   a.    
     In another embodiment, the first column shading bars  832   a  can be disposed between the two adjacent row shading bars  831  and on the opposite sides of the single sub-pixel area, for example, the red sub-pixel area  1012   a . Since the human eye is more sensitive to the red color mix, such disposition can avoid the color mix of the red color with other colors of the sub-pixel areas. 
     To be noted, although this embodiment shows the column shading bars of the two thicknesses, another embodiment may show the regular or irregular variation of the second thicknesses of the column shading bars. For example, the adjacent thicknesses are different, or the thickness of the adjacent column shading bars have a periodic variation. 
     The disposition and effect of other elements can be comprehended by referring to the above embodiments and therefore are not described here for conciseness. 
       FIG.  12    is a schematic diagram of the black matrix of the ninth embodiment of the disclosure. 
     As shown in  FIG.  12   , like the first embodiment of  FIG.  3   , the black matrix  930  of the this embodiment includes a plurality of row shading bars  931  and a plurality of column shading bars  932 . The row shading bars  931  have a first thickness. The column shading bars  932  have a second thickness. The second thickness is less than the first thickness. 
     The main difference from the first embodiment is that the second thicknesses of the column shading bars  932  are varied along the Y direction (the second direction). Herein for example, the thickness of the column shading bar  932  is lessened at the connection with the row shading bar  931  to form a sectional difference  9321 . Such design also can achieve the similar effect of the flow guiding channel as the above-mentioned second and third embodiments. 
     Although this embodiment shows the sectional difference  9321  of the column shading bar  932  is disposed at the connection, the position of the sectional difference is not limited thereto and another embodiment may show the periodic variation of the thickness of the column shading bar to form a wave-like column shading bar. 
     The disposition and effect of other elements can be comprehended by referring to the above embodiments and therefore are not described here for conciseness. 
     Summarily, this disclosure adjusts the thickness, shape and layout of the column shading bars of the black matrix to make the pixel areas evener. Thereby, the developer solution or carbon will be not easily left in the pixel areas during the process, and the remaining photoresist problem can be reduced. Therefore, the transmittance of the high-resolution product can be enhanced. 
     Although the disclosure has been described with reference to specific embodiments, this description is not meant to be construed in a limiting sense. Various modifications of the disclosed embodiments, as well as alternative embodiments, will be apparent to persons skilled in the art. It is, therefore, contemplated that the appended claims will cover all modifications that fall within the true scope of the disclosure.