Patent Publication Number: US-10777580-B2

Title: Display panel having a color block not overlapping openings in light shielding layer

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a Continuation Application (CA) of an earlier filed, pending, application, having application U.S. Ser. No. 14/806,484 and filed on Jul. 22, 2015, the content of which, including drawings, is expressly incorporated by reference herein. 
    
    
     BACKGROUND 
     Technical Field 
     The invention relates to a display panel, in particular to a display panel having high reliability. 
     Related Art 
     As the progressive of technology, flat display panels are widely applied to various fields. Because it has advantages of compact volume, low power consumption, and non-radiation, it gradually replaces traditional CRT (cathode ray tube) display device and applies to various electronic products, for example, mobile phone, portable multimedia device, notebook computer, LCD (liquid crystal display) TV or LCD monitor, etc. 
     Taking LCD device for example, the LCD device includes a display panel and a backlight module. The display panel includes a thin film transistor (TFT) substrate, a color filter substrate and a liquid crystal layer sandwiched between both the substrates. During manufacturing the conventional display panel, for example, sealant is applied to the periphery of the TFT substrate, and the liquid crystals are injected into the space formed by the sealant. Then, the TFT substrate is attached correspondingly to the color filter substrate in vacuum environment and the sealant is solidified to obtain an LCD panel. 
     Because numerous enterprises have entered the market of LCD device, this market is very competitive. Therefore, each enterprise is determined to enhance display quality and reliability thus raising competitiveness and increasing its market share. 
     SUMMARY 
     A display panel is provided with better display quality and reliability to raise product competitiveness. 
     A display panel includes a first substrate, a light shielding layer, a first color block and a second color block adjacent to the first color block, a second substrate, and a display medium layer. The light shielding layer is disposed on the first substrate and has a first opening adjacent to a first edge of the first substrate and a second opening adjacent to the first opening. The first color block and the second color block are respectively disposed on the light shielding layer along a first direction. The first opening is filled with partial of the first color block, and the first color block overlaps partial of the light shielding layer. The second opening is filled with partial of the second color block, and the second color block overlaps partial of the shielding layer. The first color block on the light shielding layer has a first overlap portion adjacent to the first edge, the second color block on the light shielding layer has a second overlap portion adjacent to the first edge, and the area of the first overlap portion and the area of the second overlap portion are different. The display medium layer is sandwiched between the first substrate and the second substrate. 
     A display panel includes a first substrate, a light shielding layer, a second substrate, a display medium layer, a first color block and a second color block adjacent to the first color block, a third color block closest to a second edge of the first substrate. The light shielding layer is disposed on the first substrate and has a first opening closest to a first edge of the first substrate, a second opening adjacent to the first opening and a third opening relatively away from the first edge along a first direction. The first color block and the second color block are respectively disposed on the light shielding layer along the first direction. The first opening and the third opening are filled with partial of the first color block, and the first color block overlaps partial of the shielding layer. The second opening is filled with partial of the second color block, and the second color block overlaps partial of the light shielding layer. The third color block is disposed on the light shielding layer along the first direction, the second edge connects to the first edge. Along a second direction substantially perpendicular to the first direction, the shortest distance from the portion of the third color block corresponding to the first opening to the second edge is different from the shortest distance from the portion of the third color block corresponding to the third opening to the second edge. The display medium layer is sandwiched between the first substrate and the second substrate. 
     A display panel includes a first substrate, a light shielding layer, a second substrate and a display medium layer, a first color block and a second color block adjacent to the first color block. The light shielding layer is disposed on the first substrate and has a first opening adjacent to a first edge of the first substrate and a second opening adjacent to the first opening. The first color block and the second color block are respectively disposed on the light shielding layer along a first direction. The first opening is filled with partial of the first color block, and the first color block overlaps partial of the light shielding layer. The second opening is filled with partial of the second color block, and the second color block overlaps partial of the light shielding layer. The first color block on the light shielding layer has a first overlap portion closest to the first edge. The second color block on the light shielding layer has a second overlap portion closest to the first edge. There is a first shortest distance from the first overlap portion to the first edge, there is a second shortest distance from the second overlap portion to the first edge, and the first shortest distance and the second shortest distance are different. The display medium layer is sandwiched between the first substrate and the second substrate. 
     In one embodiment, along the first direction, there is a first shortest distance from the first overlap portion to the first edge, there is a second shortest distance from the second overlap portion to the first edge, and the first shortest distance and the second shortest distance are different. 
     In one embodiment, the first color block and the second color block have different colors. 
     In one embodiment, the thickness of the first overlap portion is thinner than the thickness of partial of the first color block at the first opening. 
     In one embodiment, the ratio of the area of the first overlap portion to the area of the first opening is between 0.3 to 1.2. 
     In one embodiment, the light shielding layer further comprises a third opening relatively away from the first edge along the first direction, the third opening is filled with partial of the first color block, and the area of the third opening is greater than the area of the first opening. 
     In one embodiment, the first color block overlaps the light shielding layer and has a third overlap portion. The second color block overlaps the light shielding layer and has a fourth overlap portion. The first overlap portion is located between the third overlap portion and the first edge. The second overlap portion is located between the fourth overlap portion and the first edge. A spacer disposed across partial of the third overlap portion and the fourth overlap portion. The overlap area between the spacer and the third overlap portion is different from the overlap area between the spacer and the fourth overlap portion. 
     In one embodiment, the display panel further includes a third color block closest to a second edge. The third color block is disposed on the light shielding layer along the first direction. The light shielding layer further has a third opening relatively away from the first edge. The second edge connects to the first edge. Along a second direction substantially perpendicular to the first direction, there is a third shortest distance from the portion of the third color block corresponding to the first opening to the second edge, and there is a fourth shortest distance from the portion of the third color block corresponding to the third opening to the second edge, the third shortest distance and the fourth shortest distance are different. 
     In one embodiment, the first overlap portion connects to the second overlap portion to form a concave portion, there is a first longest distance from the concave portion to the first edge along the first direction, there is a fifth shortest distance from the first color block or the second color block to the first edge along the first direction, the ratio of the difference between the first longest distance and the fifth shortest distance to the length of the first opening is between 0.05 to 0.5. 
     As mentioned above, as to the display panel, the first color block and the second color block are respectively disposed on the light shielding layer along the first direction. The first opening is filled with partial of the first color block, and the first color block overlaps partial of the light shielding layer. The second opening is filled with partial of the second color block, and the second color block overlaps partial of the light shielding layer. The area of the first overlap portion of the first color block on the light shielding layer closest to the first edge is different from the area of the second overlap portion of the second color block on the light shielding layer closest to the first edge; alternatively, the first shortest distance from the first overlap portion to the first edge is different from the second shortest distance from the second overlap portion to the first edge; alternatively, the third color block closest to the second edge is disposed on the light shielding layer along the first direction, along the second direction substantially perpendicular to the first direction, the shortest distance from the portion of the third color block corresponding to the first opening to the second edge is different from the shortest distance from the portion of the third color block corresponding to the third opening to the second edge. Therefore, the border between the light shielding layer and the color block of the display panel is not aligned evenly. It can form a heterogeneous boundary to block the external particle or moisture from entering the panel through the border between the light shielding layer and the color block. It can prevent the particle pollution by external particle, and therefore raises product reliability and competitiveness. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The embodiments 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 invention, and wherein: 
         FIG. 1A  is a schematic top view showing a display panel according to the embodiment of the invention; 
         FIG. 1B  is a sectional view along line A-A in  FIG. 1A ; 
         FIG. 1C  is a schematic bottom view showing the display panel in  FIG. 1B ; 
         FIG. 1D  and  FIG. 1E  are sectional views respectively along line B 1 -B 1  and line B 2 -B 2  in  FIG. 1C ; 
         FIG. 1F  is an enlarged schematic view showing the zone C in  FIG. 1C ; 
         FIG. 2  is a schematic bottom view showing a display panel according to another embodiment of the invention; and 
         FIG. 3  is a schematic view showing a display panel according to the embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The embodiments of the invention 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. 
     Referring to  FIG. 1A  to  FIG. 1F ,  FIG. 1A  is a schematic top view showing a display panel  1  according to the embodiment of the invention.  FIG. 1B  is a sectional view along line A-A in  FIG. 1A .  FIG. 1C  is a schematic bottom view showing the display panel in  FIG. 1B .  FIG. 1D  and  FIG. 1E  are sectional views respectively along line B 1 -B 1  and line B 2 -B 2  in  FIG. 1C .  FIG. 1F  is an enlarged schematic view showing the zone C in  FIG. 1C . 
     In  FIG. 1B , the display panel  1  includes a first substrate  11 , a second substrate  12  and a display medium layer  13 . In addition, the display panel  1  further includes a light shielding layer  14 , a filter layer and a protection layer  18 . In  FIG. 1A ,  FIG. 1C ,  FIG. 1D  and  FIG. 1E , the second substrate  12 , the display medium layer  13  and the protection layer  18  are not shown. Besides, a first direction D 1 , a second direction D 2  and a third direction D 3  are shown in the figure, and the first direction D 1 , the second direction D 2  and the third direction D 3  are substantially perpendicular to each other. The first direction D 1  can be substantially parallel to the extension direction of the data line. The second direction D 2  can be substantially parallel to the extension direction of the scan line. The third direction D 3  is another direction which is substantially perpendicular to the first direction D 1  and the second direction D 2 . 
     The first substrate  11  is disposed opposite to the second substrate  12 . The display medium layer  13  is sandwiched between the first substrate  11  and the second substrate  12 . The display panel  1  can be an LCD (liquid crystal display) panel or an OLED (Organic Light-Emitting Diode) display panel. Here, the display panel  1  is the LCD panel for example, and the display medium layer  13  is a liquid crystal layer. Alternatively, if the display panel  1  is an OLED display device, the display medium layer  13  can be an organic light emitting layer, and the first substrate  11  can be a cover plate to protect the organic light emitting layer from external moisture or particle pollution. The first substrate  11  or the second substrate  12  can be made of transparent material, for example, glass, quartz or the like, plastic, rubber, fiberglass, or other polymer material; alternatively, the first substrate  11  or the second substrate  12  can be made of opaque material, for example metal-fiberglass composite plate, metal-ceramic composite plate, printed circuit board, or other material. In the embodiment, the material of the first substrate  11  or the second substrate  12  is transparent glass for example. 
     The light shielding layer  14  and the filter layer are disposed on the first substrate  11 . In the embodiment, the light shielding layer  14  and the filter layer are included in a color filter array disposed on the first substrate  11 , so the first substrate  11  with the color filter array becomes a color filter substrate. In addition, a TFT (thin film transistor) array can be disposed on the second substrate  12 , so the second substrate  12  with the TFT array becomes a TFT substrate. Alternatively in other embodiments, the light shielding layer  14  and/or the filter layer may be respectively disposed on the second substrate  12 , so it becomes a BOA (black matrix on array) substrate or becomes a COA (color filter on array) substrate, and it is not limited thereto. 
     The light shielding layer  14  includes a plurality of openings O. The openings O are the regions which the light could be transmitted (the region other than the opening O is light shielding layer  14 ). The light shielding layer  14  can be a black matrix and made of opaque material, for example metal or resin. For example, metal can be chromium, chromic hydroxide, or nitrogen oxide chromium compounds. Because the light shielding layer  14  is opaque, it forms an opaque region on the substrate  11  to further define a region with light transmittance. Referring to  FIG. 1C , the openings O includes a first opening O 1  adjacent to a first edge  111  of the first substrate  11  and a second opening O 2  adjacent to the first opening O 1 . In the embodiment, among the openings O of the shielding layer  14 , the first opening O 1  and the second opening O 2  are the adjacent openings closest to the first edge  111  of the first substrate  11 . The dimensions of the first opening O 1  and the second opening O 2  are relatively smaller than other openings O that are not closest to the first edge  111  of the first substrate  11 . 
     Besides, the filter in the embodiment for example but not limited to includes color blocks in three kinds of colors which are arranged repeatedly (R represents red color, G represents green color and B represents blue color in the figure). Its material can be transparent material for example pigment or dye. The filter layer can include a first color block  15  and a second color block  16  adjacent to the first color block  15 . The first color block  15  and the second color block  16  have different colors. In the embodiment for example, the first color block  15  is red R, the second color block  16  is green G, but they are not limited thereto. The first color block  15  and the second color block  16  are respectively disposed along a first direction D 1  and cover partial of the light shielding layer  14 . In manufacturing process, after forming the light shielding layer  14  having a plurality of openings O on the first substrate  11 , along the first direction D 1  the first color block  15  and the second color block  16  are respectively formed on the light shielding layer  14 . Thus, the first opening O 1  is filled with partial of the first color block  15  along the first direction D 1  and the first color block  15  overlaps partial of the shielding layer  14 , and the second opening O 2  is filled with partial of the second color block  16  along the first direction D 1  and the second color block  16  overlaps partial of the shielding layer  14 . 
     The first color block  15  overlaps partial of the shielding layer  14 . Thus, the first color block  15  on the shielding layer  14  has a first overlap portion  151  closest to the first edge  111  (the first overlap portion  151  is adjacent and connected to the first opening O 1 , the side of the first opening O 1  closest to the first edge  111  has a tangent line parallel to the first edge  111 , and the tangent line also acts as a virtual border of the first overlap portion  151 ). The second color block  16  overlaps partial of the shielding layer  14 . Thus, the second color block  16  on the shielding layer  14  has a second overlap portion  161  closest to the first edge  111  (the second overlap portion  161  is adjacent and connected to the second opening O 2 , and the side of the second opening O 2  closest to the first edge  111  has a tangent line parallel to the first edge  111 , and the tangent line also acts as a virtual border of the second overlap portion  161 ). Referring to  FIG. 1F , the area of the first overlap portion  151  and the area of the second overlap portion  161  are different. Here, the area of the first overlap portion  151  is smaller than the area of the second overlap portion  161 . 
     In other words, in the embodiment, as to the same color block (for example color block R), it forms a plurality of overlap portions when disposed on the light shielding layer  14 . The overlap portion closest to the first edge  111  is regarded as the first overlap portion  151 . Similarly, as to color block G, it also forms a plurality of overlap portions when disposed on the light shielding layer  14 . The overlap portion closest to the first edge  111  is regarded as the second overlap portion  161 . Because the area of the first overlap portion  151  is different from the area of the second overlap portion  161 , a heterogeneous edge is formed. In addition, referring to  FIG. 1D  and  FIG. 1E , along the first direction D 1 , there is a first shortest distance d 1  between the first overlap portion  151  and the first edge  111 , there is a second shortest distance d 2  between the second overlap portion  161  and the first edge  111 , and the first shortest distance d 1  and the second shortest distance d 2  are different. Here, the first shortest distance d 1  is greater than the second shortest distance d 2 . Therefore, in this embodiment, the edge of the first color block  15  and the second color block  16  closet to the first edge  111  of the first substrate  11  are not aligned evenly and thus to form a heterogeneous boundary. It is easier to block external particle or moisture from entering the display panel  1  through the edge of the color block. It prevents the pollution by external particle, and therefore raises product reliability and competitiveness. 
     Besides, referring to  FIG. 1D , the thickness of the first overlap portion  151  is thinner than the thickness of the partial of the first color block  15  at the first opening O 1 . In one embodiment for example, the thickness of the first overlap portion  151  is about 1.1 μm, and the thickness of the first color block  15  at the first opening O 1  is about 1.8 μm. Similarly, the thickness of the second overlap portion  161  is also thinner than the thickness of the partial of the second color block  16  at the second opening O 2 . Therefore, the filter layer has better flatness. 
     Besides, as to the same color block, when the ratio of the area of the overlap portion closest to the first edge  111  of the first substrate  11  with respect to the area of the first opening O 1  is within a specific range, an adhesion between the color block and the light shielding layer  14  can be increased (if the ratio is too high, it can not form the heterogeneous edge to block external particle; if the ratio is too low, the reliability is poor). In the embodiment, the ratio of the area of the first overlap portion  151  to the area of the first opening O 1  is between 0.3 and 1.2. Here, the area of the first opening O 1  is equal to the projected area of the first color block  15  which the first opening O 1  is filled with. 
     Referring to  FIG. 1C  again, the openings O of the light shielding layer  14  further includes a third opening O 3  relatively away from the first edge  111  along the first direction D 1 . The third opening O 3  is filled with partial of the first color block  15 , and the area of the third opening O 3  is greater than the area of the first opening O 1 . Here, the area of the third opening O 3  greater than the area of the first opening O 1  means that: the projected area of the first color block  15  which the third opening O 3  is filled with is greater than the projected area of the first color block  15  which the first opening O 1  is filled with.  FIG. 1C  shows that the third opening O 3  and the first opening O 1  are adjacent openings. Alternatively, the third opening O 3  may be toward the first direction D 1  and it is not adjacent to the first opening O 1 , and it is not limited thereto. 
     Besides, in the embodiment, the first color block  15  overlaps the light shielding layer  14  and has a third overlap portion  152 . The second color block  16  overlaps the light shielding layer  14  and has a fourth overlap portion  162 . The first overlap portion  151  is located between the third overlap portion  152  and the first edge  111 . The second overlap portion  161  is located between the fourth overlap portion  162  and the first edge  111 . In addition, a spacer S can disposed across the third overlap portion  152  and the fourth overlap portion  162 . The material of the spacer S can be resin, silicate, fiberglass, or other photosensitive resist material, and it is not limited thereto. The spacer S keeps an interval between the first substrate  11  and the second substrate  12 , so as to supply the accommodation space filled by the liquid crystal molecules. In the embodiment, the overlap area between the spacer S and the third overlap portion  152  is different from the overlap area between the spacer S and the fourth overlap portion  162 . Here, the overlap area between the spacer S and the third overlap portion  152  is greater than the overlap area between the spacer S and the fourth overlap portion  162 . In addition, although  FIG. 1C  only shows one spacer S, actually, the display panel  1  has a plurality of the spacers S. 
     Besides, the first substrate  11  further includes a second edge  112  connecting to the first edge  111 . The color filter layer further includes a third color block  17  closest to the second edge  112 . The term “closest to” means that there is no other color block between the third color block  17  and the second edge  112 . The color of the third color block  17  may be the same with or different from that of the first color block  15  or the second color block  16 . The third color block  17  is disposed on the light shielding layer  14  along the direction D 1 . Although the third color block  17  closest to the second edge  112  is disposed, the third color block  17  will not be seen when overlooking the first substrate  11  because the third color block  17  is not injected into any opening O. But as shown in  FIG. 1C , the third color block  17  is seen when looking up and seeing the first substrate  11 . Along the second direction D 2 , there is a third shortest distance d 3  from the portion of the third color block  17  corresponding to the first opening O 1  to the second edge  112 . Along a second direction D 2 , there is a fourth shortest distance d 4  from the portion of the third color block  17  corresponding to the third opening O 3  to the second edge  112 . The third shortest distance d 3  is different from the fourth shortest distance d 4 . Thus similarly, the edge of the third color block  17  closest to the second edge  112  is also not aligned evenly. Thus, the edge of the third color block  17  also forms a heterogeneous boundary. It is easier to block external particle or moisture from entering the display panel  1  through the edge of the third color block  17 . Therefore it raises product reliability. 
     Besides, referring to  FIG. 1B  again, the protection layer  18  (for example over-coating) can cover the light shielding layer  14  and the color filter layer. The material of the protection layer  18  can be photoresist, resin material, or inorganic materials (for example SiOx/SiNx), etc. to protect the light shielding layer  14  and the color filter layer from damage due to follow-up manufacturing process. In addition, the display panel  1  further includes a sealant (not shown in the figure). The sealant is disposed between the first substrate  11  and the second substrate  12  to enclose the peripheral between the first substrate  11  and the second substrate  12 . The sealant is disposed corresponding to the periphery light shielding layer  14  of the display panel  1 . Thus, when looking down the display panel  1 , the sealant is covered by the light shielding layer  14 . The sealant may be light curing adhesive (for example UV curing adhesive) and it is applied to and surrounds the fringes of display area between the first substrate  11  and the second substrate  12  for example but not limited to. In addition, the sealant, the first substrate  11  and the second substrate  12  may form an accommodation space (not shown in the figure), and the display medium layer  13  can be disposed in the accommodation space. Here, for example but not limited to, ODF (one drop filling) is utilized to fill the accommodation space enclosed by the sealant with the liquid crystal molecules. 
     In addition, the display panel  1  may further includes a plurality of scan lines and a plurality of data lines (no shown in the figure). The scan lines and the data lines are interlaced to define a plurality of pixels. Therefore, when the scan lines of the display panel  1  receive a scan signal, the TFTs corresponding to the respective scan lines are accordingly conducted and data signals corresponding to the respective pixel of column are transmitted to the corresponding pixels by the data lines. Thus the display panel  1  can display image screen. 
     Referring to  FIG. 2 , it is a schematic bottom view showing a display panel  1   a  according to another embodiment of the invention. Here, only the first color block  15   a  and the second color block  16   a  of the color filter layer are shown in the display panel  1   a  in  FIG. 2 . Other color blocks, the second substrate  12 , the display medium layer  13  and the protection layer  18  are also not shown. 
     The display panel  1   a  has the same elements and features with those of the display panel  1 . However, the difference from the display panel  1  in  FIG. 1C  is that along the third direction D 3 , the first overlap portion  151  of the first color block  15   a  and the second overlap portion  161  of the second color block  16   a  connects to form a concave portion U (namely, along the third direction D 3 , an interval exist between the first overlap portion  151  and the second overlap portion  161 ). There is a first longest distance d 5  from the concave portion U to the first edge  111  along the first direction D 1 , there is a fifth shortest distance d 6  from the first color block  15   a  or the second color block  16   a  to the first edge  111 . Here, it shows that the ratio of the difference between the first longest distance d 5  and the fifth shortest distance d 6  with respect to the length of the first opening O 1  is between 0.05 and 0.5. The length of the first opening O 1  means the maximum length of the first opening O 1  along the first direction D 1 . The concave portion U (namely, the interval between the two) formed by the first overlap portion  151  and the second overlap portion  161  form a heterogeneous boundary at the edge of the color filter layer. Further, when the sealant is disposed here (the edge of the filter layer), it increases the contact area of the sealant and the color filter layer thus to enhance the adhesion property of the seal agent and the color filter layer. 
     Besides, the technique features of other elements of the display panel  1   a  can refer to those of the display device  1 , they are not repeated here again. 
     Besides, Referring to  FIG. 3 , it is a schematic view showing a display panel  2  according to the embodiment of the invention. 
     The display device  2  includes a display panel  3  and a backlight module  4 . The display panel  3  and the backlight module  4  are disposed opposite to each other. The display device  2  in the embodiment is an LCD device, and the display panel  3  employs one of the above mentioned display panel  1 ,  1   a , or other various implementation. Because specific technique contents can refer to the above, they are not repeated here again. When the light beam E emitted from the backlight module  4  passes through the display panel  3 , it displays colors to form an image by each pixel of the display panel  3 . 
     As mentioned above, as to the display panel, the first color block and its adjacent second color block are respectively disposed on the light shielding layer along the first direction. The first opening is filled with partial of the first color block, and the first color block overlaps partial of the light shielding layer. The second opening is filled with partial of the second color block, and the second color block overlaps partial of the light shielding layer. The area of the first overlap portion of the first color block closest to the first edge on the light shielding layer is different from the area of the second overlap portion of the second color block closest to the first edge on the light shielding layer; alternatively, the first shortest distance of the first overlap portion to the first edge is different from the second shortest distance of the second overlap portion to the first edge; alternatively, the third color block closest to the second edge is disposed on the light shielding layer along the first direction. Along the second direction substantially perpendicular to the first direction, the shortest distance from the portion of the third color block corresponding to the first opening to the second edge is different from the shortest distance from the portion of the third color block corresponding to the third opening to the second edge. Therefore, the border between the light shielding layer and the color block of the display panel is not aligned evenly. It can form a heterogeneous boundary to block the external particle or moisture from entering the panel through the border between the light shielding layer and the color block. It prevent the display panel from the pollution by external particle, and therefore raises product reliability and competitiveness. 
     Although the invention 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 invention.