Patent Publication Number: US-2022238617-A1

Title: Display device

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application claims the benefits of the Chinese Patent Application Serial Number 201610809206.8, filed on Sep. 8, 2016, the subject matter of which is incorporated herein by reference. 
     This application is a continuation (CA) of U.S. patent application for “Display device”, U.S. application Ser. No. 16/995,867 filed Aug. 18, 2020; U.S. application Ser. No. 16/995,867 is a continuation (CA) of U.S. application Ser. No. 16/264,761 filed Feb. 1, 2019; U.S. application Ser. No. 16/264,761 is a continuation (CA) of U.S. application Ser. No. 15/695,051 filed Sep. 5, 2017; and the subject matters of which are incorporated herein by reference. 
    
    
     BACKGROUND 
     1. Field 
     The present disclosure relates to a display device and, more particularly, to a display device with improved manufacture yield. 
     2. Description of Related Art 
     With the continuous advancement of technologies related to displays, all the display devices are now developed toward compactness, thinness, and lightness. This trend makes thin displays, such as liquid crystal display devices, organic light-emitting diode display devices and inorganic light-emitting diode display devices, replacing cathode-ray-tube displays as the mainstream display devices on the market. Applications of thin displays are numerous. Most electronic products for daily use, such as mobile phones, notebook computers, video cameras, still cameras, music displays, mobile navigators, and TV sets, employ such display panels. 
     The organic light-emitting diode (OLED) display devices has advantages of: light weight, thin thickness, high brightness, fast response, large viewing angle, no need for backlight, low manufacturing cost and flexibility, and is considered as a next-generation display device. 
     During the manufacturing process of the OLED display device, light emitting layers capable of emitting different colors are formed by vapor depositions. However, if pixel units with different colors are too close, the mask used for vapor depositions has to be finer, and color mix of adjacent pixel units with different colors may be occurred. 
     Therefore, it is desirable to provide an OLED display device, wherein the design of the pixel units is modified to improve the manufacture yield of the OLED display device. 
     SUMMARY 
     An object of the present disclosure is to provide a display device, wherein the manufacture yield of the display device can be improved. 
     In one aspect of the present disclosure, the display device comprises: a first substrate; a data line disposed on the first substrate and extending along a data-line-extension direction; and plural pixel units disposed on the first substrate. Herein, each of the plural pixel units comprises: a transistor disposed on the first substrate; a first insulating layer disposed on the transistor, wherein the first insulating layer comprises an upper surface, and at least a via hole passing through the first insulating layer; a first electrode disposed on the upper surface of the first insulating layer, wherein the first electrode electrically connects to the transistor through the via hole; a pixel defining layer disposed on the first electrode and the first insulating layer, wherein the pixel defining layer exposes a part of the first electrode to define a light emitting region; a light emitting layer disposed on the first electrode and in the light emitting region; and a second electrode disposed on the light emitting layer. Herein, in a normal direction view of the first substrate, and in a first pixel unit of the pixel units, the via hole has a first outline on the upper surface of the first insulating layer, and the light emitting region has a second outline on the upper surface of the first insulating layer; and the first outline has a first point, the second outline has a second point, a minimum distance between the first outline and the second outline is a distance between the first point and the second point, a first extension direction is an extending direction of a connecting line between the first point and the second point, an acute angle is included between the first extension direction and the data-line-extension direction, and the acute angle is greater than or equal to 10 degrees and less than or equal to 80 degrees. 
     In another aspect of the present disclosure, the display device comprises: a first substrate; a data line disposed on the first substrate and extending along a data-line-extension direction; and plural pixel units disposed on the first substrate. Herein, each of the plural pixel units comprises: a transistor disposed on the first substrate, wherein the transistor comprises a first metal layer, a semiconductor layer and a second metal layer, the second metal layer is disposed on the semiconductor layer, and the first metal layer corresponds to the semiconductor layer; a first insulating layer disposed on the transistor, wherein the first insulating layer comprises an upper surface, and at least a via hole passing through the first insulating layer; a first electrode disposed on the first insulating layer, wherein the first electrode electrically connects to the second metal layer through the via hole; a pixel defining layer disposed on the first electrode and the first insulating layer, wherein the pixel defining layer exposes a part of the first electrode to define a light emitting region; a light emitting layer disposed on the first electrode; and a second electrode disposed on the light emitting layer. Herein, in a first pixel unit of the pixel units, the via hole has a first outline on the upper surface of the first insulating layer, and the light emitting region has a second outline on the upper surface of the first insulating layer; and the first outline has a first point, the second outline has a second point, a minimum distance between the first outline and the second outline is a distance between the first point and the second point, a first extension direction is an extending direction of a connecting line between the first point and the second point, and the first extension direction is not perpendicular and not parallel to the data-line-extension direction. 
     In the display device of the present disclosure, when the first extension direction, which is belonged to an extending direction of a connecting line defined by a minimum distance between the first outline of the via hole and the second outline of the light emitting region on the upper surface of the first insulating layer, is not perpendicular and not parallel to the data-line-extension direction, the connecting line between the via hole and the light emitting region is not aligned with the data line. When the connecting line between the via hole and the light emitting region is designed to be not aligned with the data line, the gaps between the pixel units can be maintained; therefore, the manufacture yield of the display device can be improved. 
     More specifically, when the connecting line between the via hole and the light emitting region is disposed to be perpendicular or parallel to the data-line-extension direction (which means the first extension direction of the minimum distance between the first outline of the via hole and the second outline of the light emitting region is perpendicular or parallel to the data-line-extension direction) and the arrangement of the light emitting regions in the display region is maintained, the via hole is too close to the present pixel unit or the adjacent pixel unit, the short circuit or color mix between adjacent pixel units may be occurred, resulting in the manufacture yield of the display device decreased. In addition, the mask for forming the light emitting layer has to be finer and more delicate. However, if the gaps between the light emitting regions are increased to prevent the color mix, the number of the pixel units in the display region of the display device has to be decreased. Hence, in the display device of the present disclosure, by designing the connecting line between the via hole and the light emitting region to be not aligned with the data line, the manufacture yield of the display device can be improved without decreasing the number of the pixel units when the area of the display region is limited. 
     Other objects, advantages, and novel features of the disclosure will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a cross sectional view of an OLED display device according to Embodiment 1 of the present disclosure. 
         FIG. 2  is a cross sectional view of a display region of an OLED display device according to Embodiment 1 of the present disclosure. 
         FIG. 3  is a top view showing a part of a display region of an OLED display device according to Embodiment 1 of the present disclosure. 
         FIG. 4  is an enlarge view of a region comprising a first pixel unit shown in  FIG. 3 . 
         FIG. 5  is an enlarge view of a region comprising a first pixel unit, a second pixel unit and a third pixel unit shown in  FIG. 3 . 
         FIG. 6  is a top view showing a part of a display region of an OLED display device according to Embodiment 2 of the present disclosure. 
         FIG. 7  is a top view showing a part of a display region of an OLED display device according to Embodiment 3 of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENT 
     The following embodiments when read with the accompanying drawings are made to clearly exhibit the above-mentioned and other technical contents, features and effects of the present disclosure. Through the exposition by means of the specific embodiments, people would further understand the technical means and effects the present disclosure adopts to achieve the above-indicated objectives. Moreover, as the contents disclosed herein should be readily understood and can be implemented by a person skilled in the art, all equivalent changes or modifications which do not depart from the concept of the present disclosure should be encompassed by the appended claims. 
     Furthermore, the ordinals recited in the specification and the claims such as “first”, “second” and so on are intended only to describe the elements claimed and imply or represent neither that the claimed elements have any proceeding ordinals, nor that sequence between one claimed element and another claimed element or between steps of a manufacturing method. The use of these ordinals is merely to differentiate one claimed element having a certain designation from another claimed element having the same designation. 
     Furthermore, the ordinals recited in the specification and the claims such as “above”, “over”, or “on” are intended not only directly contact with the other substrate or film, but also intended indirectly contact with the other substrate or film. 
     Embodiment 1 
       FIG. 1  is a cross sectional view of an OLED display device of the present embodiment. In the process for preparing the OLED display device, a first substrate  11  and a second substrate  12  are provided. Organic light emitting diodes  15  and pixel defining layer  16  are disposed on the first substrate  11 , wherein a part of the pixel defining layer  16  is disposed between two adjacent organic light emitting diodes  15 . In addition, the display device may further comprise at least a spacer  14  disposed on the pixel defining layer. In this embodiment, plural spacers  14  are disposed between the first substrate  11  and the second substrate  12 . In this embodiment, a glue material  13  (in the present embodiment, a frit) is disposed adjacent to edges of the second substrate  12  in advance, which is adhered onto the second substrate  12  through a dispensing process and an annealing process. Next, the first substrate  11  and the second substrate  12  are assembled, wherein the spacers  14  are disposed correspondingly to parts of the pixel defining layer  16  without pixel openings  161 . After a laser annealing process, the glue material  13  is adhered between the first substrate  11  and the second substrate  12 , and the OLED display device of the present embodiment is obtained. 
     In the present embodiment, the first substrate  11  and the second substrate  12  can be a glass substrate, a plastic substrate, or other flexible substrate or film, such us polyimide, but other embodiments of the present disclosure are not limited thereto. When the first substrate  11  and the second substrate  12  are flexible substrates or films, the OLED display device is a flexible OLED display device. Furthermore, in some embodiment of the present disclosure, the OLED display device is not equipped with the second substrate  12 . 
     In addition, as shown in  FIG. 1 , the OLED display device of the present embodiment comprises a display region AA and a border region B, wherein the border region B is a region with circuits formed thereon, and the display region AA is a region with organic light emitting diodes  15  and transistors (not shown in the figure) formed thereon. Furthermore, in the present embodiment, the organic light emitting diodes  15  can respectively emit red, green or blue light, but other embodiments of the present disclosure are not limited thereto. For example, the organic light emitting diodes  15  can be white organic light emitting diodes; and in this case, one of the first substrate  11  and the second substrate  12  is disposed with a color filter layer (not shown in the figure). 
     In addition, as shown in  FIG. 1 , in the OLED display device of the present embodiment, the organic light emitting diode  15  comprises: a first electrode  151 , a light emitting layer  152  and a second electrode  153  sequentially disposed on the first substrate  11 . The first electrode  151  electrically connects to a transistor (not shown in the figure) disposed on the first substrate  11 . The pixel defining layer  16  is disposed on a part of the first electrode  151 , and a light emitting region is defined by the pixel opening  161  of the pixel defining layer  16 . Herein, the organic light emitting diode  15  containing only the first electrode  151 , the light emitting layer  152  and the second electrode  153  is exemplified, but the present disclosure is not limited thereto. Other elements capable of using in the organic light emitting diode can also be used in the organic light emitting diode of the present disclosure. For example, the elements such as an electron transporting layer, an electron injection layer, a hole transporting layer, a hole injection layer, and other layers capable of facilitating the transporting or combination of the holes and the electrons can also be used in the organic light emitting diode of the present disclosure. 
     Hereinafter, the structure of the pixel units on the display region AA of the first substrate in the OLED display device of the present embodiment and a manufacturing process thereof are illustrated in detail. 
       FIG. 2  is a cross sectional view of a display region of the OLED display device of the present embodiment. In the display device of the present embodiment, a transistor TFT is disposed on the first substrate  11 , and the manufacturing process of the transistor TFT are briefly described below. First, a first substrate  11  is provided. A semiconductor layer  21  is formed on the first substrate  11 , wherein the semiconductor layer  21  is a polysilicon layer formed by amorphous silicon after laser annealing. However, other embodiments of the present disclosure are not limited thereto. Next, a gate insulating layer  22 , a first metal layer  23  and a second insulating layer  24  are sequentially formed on the first substrate  11 . The first metal layer  23  is used as a gate electrode. The gate insulating layer  22  and the second insulating layer  24  can be prepared by any insulting material such as silicon oxide or silicon nitride. However, other embodiments of the present disclosure are not limited thereto. Then, a second metal layer  25  is formed on the second insulating layer  24 . Herein, the second metal layer  25  of the transistor TFT further penetrates through the second insulating layer  24  and used as a source electrode and a drain electrode. Part of the second metal layer  25  locating outside the transistor TFT further comprises a data line  251 . 
     Herein, the transistor TFT on the first substrate  11  is a low temperature polysilicon thin film transistor. However, in other embodiment of the present disclosure, the aspect and the structure of the thin film transistor is not limited to the transistor TFT shown in  FIG. 2 . In addition, in other embodiment of the present disclosure, the components of the transistor are not limited to the layers shown in  FIG. 2 , and may comprise other layers such as a buffer layer or another insulating layer to facilitate the adhesion between layers and the electric property of the transistor. In other embodiment of the present disclosure, the transistor can be a bottom gate transistor, wherein a first metal layer  23  is formed on the first substrate  11 , followed by disposing the gate insulating layer  22  and the semiconductor layer  21 , and then disposing other layers. 
     After forming the second metal layer  25 , a first insulating layer  26 , a first electrode layer  151 , a pixel defining layer  16 , an organic layer  152  and a second electrode layer  153  are sequentially formed on the first substrate  11 , and the organic light emitting diode  15  of the present embodiment is obtained. Herein, the first insulating layer  26  can be prepared by any material for a planer layer, but the present disclosure is not limited thereto. The pixel defining layer  16  can be prepared by any insulating material such as a resin, and the pixel opening  161  for defining the light emitting region E is formed by a patterning process. The first electrode layer  151  can be a reflective electrode, a transparent electrode or a semi-transparent electrode. In the present embodiment, the first electrode layer  151  is the reflective electrode. The second electrode layer  153  can be a transparent electrode or a semi-transparent electrode. 
     Herein, the reflective electrode can be, for example, an electrode prepared by Ag, Ge, Al, Cu, Mo, Ti, Sn, AlNd, ACX, APC and so on. The transparent electrode can be a transparent conductive oxide electrode, such as an ITO electrode, an IZO electrode or an ITZO electrode. The semi-transparent electrode can be a metal thin film electrode, for example, an Mg/Ag alloy thin film electrode, an Au thin film electrode, a Pt thin film electrode, or an Al thin film electrode. In addition, if it is necessary, the second electrode layer  153  of the present embodiment can be a composite electrode containing a transparent electrode and a semi-transparent electrode, for example, a composite electrode of a TCO electrode and a Pt thin film electrode. It should be noted that the material of the first electrode layer  151  and the second electrode layer  153  are not limited thereto in other embodiment of the present disclosure. 
     In the present disclosure, the aforementioned layers can be prepared by any patterning process to form a specific pattern containing an opening. 
       FIG. 3  is a top view showing a part of a display region of an OLED display device of the present embodiment, wherein  FIG. 2  is a cross sectional view of  FIG. 3  according to the line L 1 -L 1 ′, and  FIG. 3  is a normal direction view of the first substrate shown in  FIG. 2 . As shown in  FIG. 3 , the display device of the present embodiment comprises plural pixel units, for example: a first pixel unit Px 1 , a second pixel unit Px 2 , a third pixel unit Px 3  and a fourth pixel unit Px 4 .  FIG. 4  is an enlarge view of a region comprising a first pixel unit Px 1  shown in  FIG. 3 . As shown in  FIG. 2  to  FIG. 4 , the display device of the present embodiment comprises: a first substrate  11 ; a data line  251  disposed on the first substrate  11  and extending along a data-line-extension direction Y; and plural pixel units (including a first pixel unit Px 1 , a second pixel unit Px 2 , a third pixel unit Px 3  and a fourth pixel unit Px 4 ) disposed on the first substrate  11 . Each of the plural pixel units comprise: a transistor TFT disposed on the first substrate  11 , wherein the transistor TFT comprises a first metal layer  23 , a semiconductor layer  21  and a second metal layer  25 , the second metal layer  25  is disposed on the semiconductor layer  21 , and the first metal layer  23  corresponds to the semiconductor layer  21 ; a first insulating layer  26  disposed on the transistor TFT, wherein the first insulating layer  26  comprises an upper surface  261 , at least a via hole  262  passing through the first insulating layer  26 ; a first electrode  151  disposed on the upper surface  261  of the first insulating layer  26 , wherein the first electrode  151  electrically connects to the second metal layer  25  through the via hole  262  (more specifically, parts of the first electrode  151  extends into the via hole  262  and electrically connects to the second metal layer  25 ); a pixel defining layer  16  disposed on the first electrode  151  and the first insulating layer  26 , wherein the pixel defining layer  16  exposes a part of the first electrode  151  to define a light emitting region E; a light emitting layer  152  disposed on the first electrode  151  and in the light emitting region E; and a second electrode  153  disposed on the light emitting layer  152 . 
     As shown in  FIG. 3 , in the display device of the present embodiment, one of the pixel units is a first pixel unit Px 1 . As shown in  FIG. 2  and  FIG. 4 , in the first pixel unit Px 1 , the via hole  2621  (which is equal to the via hole  262  shown in  FIG. 2 ) has a first outline  2631  on the upper surface  261  of the first insulating layer  26 , and the light emitting region E 1  (which is equal to the light emitting region E shown in  FIG. 2 ) has a second outline  1611  on an upper surface of the first electrode  1511  (which is equal to the first electrode  151  shown in  FIG. 2 , and the second outline  1611  on an upper surface of the first electrode  1511  is equal to that on the upper surface  261  of the first insulating layer  26 ). Herein, in the normal direction view of the first substrate  11 , the first outline  2631  has a first point P 1 , the second outline  1611  has a second point P 2 , a minimum distance between the first outline  2631  and the second outline  1611  is a distance between the first point P 1  and the second point P 2 , a first extension direction Dir 1  is an extending direction of a connecting line between the first point P 1  and the second point P 2 , and the first extension direction Dir 1  is not perpendicular and not parallel to the data-line-extension direction Y. In another embodiment of the present disclosure, an acute angle θ 1  is included between the data-line-extension direction Y and the first extension direction Dir 1  defined by the extending direction of the connecting line between the first point P 1  and the second point P 2 , and the acute angle θ 1  is greater than or equal to 10 degrees and less than or equal to 80 degrees. Herein, the acute angle θ 1  is measured by the acute angle included by the first extension direction Dir 1  and the data-line-extension direction Y. It should be noted that the data line can be a linear line, a curved line or a line with a bending potion, and any data lines are fallen into the scope of the present disclosure as long as the data line has a substantial data-line-extension direction Y. In the display device of the present embodiment, when the first extension direction Dir 1  defined by the connecting line with the minimum distance between the first outline  2631  of the via hole  2621  (which is equal to the via hole  262  shown in  FIG. 2 ) on the upper surface  261  of the first insulating layer  26  and the second outline  1611  of the light emitting region E 1  (which is equal to the light emitting region E shown in  FIG. 2 ) in the normal view of the first substrate  11  is different from the data-line-extension direction Y, and an acute angle is formed between the first extension direction Dir 1  and the data-line-extension direction Y, the connecting line between the via hole  2621  and the light emitting region E 1  is not aligned with the data line  251 . When the connecting line between the via hole  2621  and the light emitting region E 1  is designed to be not aligned with the data line  251 , the distance between the light emitting region E 1  and the data line  251  can be maintained; therefore, the manufacture yield of the display device can be improved. 
     More specifically, when the connecting line with the minimum distance between the via hole  2621  and the light emitting region E 1  is disposed to be perpendicular to the data-line-extension direction Y, which means the first extension direction Dir 1  defined by the connecting line with the minimum distance between the first outline  2631  of the via hole  2621  (which is equal to the via hole  262  shown in  FIG. 2 ) on the upper surface  261  of the first insulating layer  26  and the second outline  1611  of the light emitting region E 1  (which is equal to the light emitting region E shown in  FIG. 2 ) is substantially perpendicular to the data-line-extension direction Y, color mix between adjacent pixel units may be occurred if the gap between the via hole  2621  (which is equal to the via hole  262  shown in  FIG. 2 ) and the light emitting region E 1  is maintained; and therefore, the manufacture yield of the display device is reduced. In addition, in the aforementioned situation, the mask for forming the light emitting layer  152  has to be finer and more delicate. It could influence the overall light emitting efficiency of the OLED device. When the connecting line between the via hole  2621  and the light emitting region E 1  is disposed to be parallel to the data-line-extension direction Y, which means the first extension direction Dir 1  defined by the extending direction of the connecting line with the minimum distance between the first outline  2631  of the via hole  2621  (which is equal to the via hole  262  shown in  FIG. 2 ) and the second outline  1611  of the light emitting region E 1  (which is equal to the light emitting region E shown in  FIG. 2 ) is substantially parallel to the data-line-extension direction Y, the region that the first electrode can be exposed therefrom is reduced if the arrangement of the via hole  2621  (which is equal to the via hole  262  shown in  FIG. 2 ) in the display region is maintained; which means the area of the light emitting region E 1  is reduced, resulting in the overall light emitting efficiency is reduced. However, if the gap between the light emitting regions E 1  (which is equal to the light emitting region E shown in  FIG. 2 ) and the via hole  2621  is increased to prevent the aforementioned situation, the numbers of the pixel units disposed in the display region is reduced. Hence, in the display device of the present disclosure, when the connecting line with the minimum distance between the via hole  2621  and the light emitting regions E 1  is not aligned with the data line  251  which means that the light emitting regions E 1  is not aligned with the via hole  2621 , the manufacture yield of the display device can be improved without reducing the number of the pixel units in a limited display region. 
     In addition, as shown in  FIG. 4 , in the present embodiment, in the normal direction view of the first substrate, the first outline  2631  has an arc edge. In particular, the first outline  2631  has an ellipse like shape. Herein, a maximum width of the first outline  2631  in the data-line-extension direction Y is defined as a first maximum width W 1 , a maximum width of the first outline  2631  in a direction X perpendicular to the data-line-extension direction Y is defined as a second maximum width W 2 , and the first maximum width W 1  is different from the second maximum width W 2 . In another embodiment, the first maximum width W 1  is greater than the second maximum width W 2 ; in this case, a direction of the long axis of the ellipse like shape of the first outline  2631  is approximately parallel to the data-line-extension direction Y. If the first maximum width W 1  is less than the second maximum width W 2 , the direction of the long axis of the ellipse like shape of the first outline  2631  is approximately perpendicular to the data-line-extension direction Y, resulting in the edge of the first outline  2631  is too close to the data line  251  (please refer to  FIG. 3 ). If there is a mismatch occurred in the lithography process for forming the via hole  2621 , a short circuit may be easily occurred. 
       FIG. 5  is an enlarge view of a region comprising a first pixel unit Px 1 , a second pixel unit Px 2  and a third pixel unit Px 3  shown in  FIG. 3 . As shown in  FIG. 2  and  FIG. 5 , in the display device of the present embodiment, the second pixel unit Px 2  of the plural pixel units which is adjacent to the first pixel unit Px 1 , and is the closest pixel unit near to the first pixel unit Px 1 . In the second pixel unit Px 2 , the via hole  2622  (which is equal to the via hole  262  shown in  FIG. 2 ) has a third outline  2632  on the upper surface  261  of the first insulating layer  26 , and the light emitting region E 2  (which is equal to the light emitting region E shown in  FIG. 2 ) has a fourth outline  1612  on the upper surface  261  of the first insulating layer  26 ; wherein, the third outline  2632  has a third point P 3 , the fourth outline  1612  has a fourth point P 4 , a minimum distance between the third outline  2632  and the fourth outline  1612  is a distance between the third point P 3  and the fourth point P 4  in the normal direction view of the first substrate  11 , a second extension direction Dir 2  is an extending direction of the connecting line between the third point P 3  and the fourth point P 4 , and the second extension direction Dir 2  is different from the first extension direction Dir 1  defined by the extending direction of the connecting line between the first point P 1  and the second point P 2 . In another embodiment of the present disclosure, an angle θ 2  included between the first extension direction Dir 1  and the second extension direction Dir 2  is greater than or equal to 60 degrees and less than or equal to 120 degrees. 
     As shown in  FIG. 2 ,  FIG. 3  and  FIG. 5 , in the pixel units of the display device of the present embodiment, the pixel units are arranged along the data-line-extension direction Y or/and a direction X perpendicular to the data-line-extension direction Y. The pixel units further comprise a third pixel unit Px 3 , which is adjacent to the first pixel unit Px 1  and locates in the direction X (It means a connection line between a center of the first pixel unit Px 1  and a center of the third pixel unit Px 3  is substantially along the direction X). In the third pixel unit Px 3 , the via hole  2623  (which is equal to the via hole  262  shown in  FIG. 2 ) has a fifth outline  2633  on the upper surface  261  of the first insulating layer  26 , and the light emitting region E 3  (which is equal to the light emitting region E shown in  FIG. 2 ) has a sixth outline  1613  on the upper surface  261  of the first insulating layer  26 . The fifth outline  2633  has a fifth point P 5 , the sixth outline  1613  has a sixth point P 6 , a minimum distance between the fifth outline  2633  and the sixth outline  1613  is a distance between the fifth point P 5  and the sixth point P 6  in the normal direction view of the first substrate  11 , and a third extension direction Dir 3  is an extending direction of a connecting line between the fifth point P 5  and the sixth point P 6 . Therein, a maximum width of the light emitting region E 1  of the first pixel unit Px 1  (the second outline  1611 ) in the first extension direction Dir 1  (defined by an extending direction of the connecting line with the minimum distance of the first point P 1  and the second point P 2 ) is defined as a third maximum width W 3 , a maximum width of the light emitting region E 3  of the third pixel unit Px 3  (the sixth outline  1613 ) in the third extension direction Dir 3  (defined by an extending direction of the connecting line with the minimum distance of the point P 5  and the point P 6 ) is defined as a fourth maximum width W 4 , and the third maximum width W 3  is different from the fourth maximum width W 4 . 
     In addition, in the present embodiment, the third pixel unit Px 3  and the first pixel Px 1  unit substantially have the same color; but the present disclosure is not limited thereto. 
     Furthermore, as shown in  FIG. 3  and  FIG. 5 , in the present embodiment, the light emitting region E 1  of the first pixel unit Px 1  has an ellipse like shape in the normal direction view of the first substrate  11 , and the first electrode  151  of the first pixel unit Px 1  overlaps the data line  251 . The pixel units further comprise a second pixel unit Px 2  and a fourth pixel unit Px 4 , and an area of the light emitting region E 2  of the second pixel unit Px 2  is less than an area of the light emitting region E 4  of the fourth pixel unit Px 4 . The second pixel unit Px 2  and the fourth pixel unit Px 4  respectively locate at two sides of the first pixel unit Px 1  or the data line  251  (in other words, the data line  251  is located between the second pixel unit Px 2  and the fourth pixel unit Px 4 ), the second pixel unit Px 2  and the fourth pixel unit Px 4  are arranged in the same row or the same column (it means a connection line between a center of the second pixel unit Px 2  and a center of the fourth pixel unit Px 4  is substantially along the data-extension-direction or perpendicular to the data-extension-direction), the first pixel unit Px 1  and the second pixel unit Px 2  are not arranged in the same row or the same column, and the first pixel unit Px 1  and the fourth pixel unit Px 4  are not arranged in the same row or the same column. Herein, “one pixel unit and another pixel unit are (not) arranged in the same row or the same column” refers to that a connection line between a center of one pixel unit and a center of another pixel unit is (not) along the data-extension-direction or (not) perpendicular to the data-extension-direction. The second pixel unit Px 2  is adjacent to the first pixel unit Px 1 , and an extension line of a long axis of the light emitting region E 1  of the first pixel unit Px 1  overlaps with the second pixel unit Px 2 ; wherein the fourth pixel unit Px 4  is adjacent to the first pixel unit Px 1 , and an extension line of a short axis of the light emitting region E 1  of the first pixel unit Px 1  overlaps with the fourth pixel unit Px 4 . 
     As shown in  FIG. 5 , in the present embodiment, even though both the light emitting region E 1  of the first pixel unit Px 1  and the light emitting region E 3  of the third pixel unit Px 3  have ellipse like shapes, the direction of the long axis of the light emitting region E 1  and a direction of the long axis of the light emitting region E 3  are different. In particular, when the direction of the long axis of the light emitting region E 1  of the first pixel unit Px 1  is different from the direction of the long axis of the light emitting region E 3  of the third pixel unit Px 3  (in particular, the directions of the long axes of the light emitting region E 1  of the first pixel unit Px 1  and the light emitting region E 3  of the third pixel unit Px 3  are directed to the second pixel unit Px 2  with a smaller light emitting region than the fourth pixel unit Px 4 ), the brightness of the second pixel unit Px 2  can be compensated. Therefore, the overall brightness of the display device can further be more even. 
     In the present embodiment, both the light emitting region E 1  of the first pixel unit Px 1  and the light emitting region E 3  of the third pixel unit Px 3  have ellipse like shapes, but the present disclosure is not limited thereto. The light emitting region E 1  of the first pixel unit Px 1  and the light emitting region E 3  of the third pixel unit Px 3  may have a rectangle like shape, as long as the direction of the long axis of the light emitting region E 1  and a direction of the long axis of the light emitting region E 3  are different, and the second pixel unit Px 2  with smaller area is overlapped with an extension line of the long axis of the rectangle like shape. 
     In addition, as shown in  FIG. 4 , in the first pixel unit Px 1 , in a direction perpendicular to the first extension direction Dir 1 , a first gap D 1  and a second gap D 2  are between the second outline  1611  of the light emitting region E 1  and an adjacent edge of the first electrode  1511 , and the first gap D 1  is different from the second gap D 2 . 
     Furthermore, as shown in  FIG. 5 , in second pixel unit Px 2 , in a direction perpendicular to the second extension direction Dir 2 , a first gap D 11  and a second gap D 21  are also between the second outline  1612  of the light emitting region E 2  and an adjacent edge of the first electrode  1512 , and the first gap D 11  is different from the second gap D 21 . Herein, the light emitting region of the second pixel unit Px 2  has a rectangle like shape, and has a first edge  1612   a  adjacent to the via hole  2622 , a second edge  1612   b  opposite to the first edge  1612   a , and a third edge  1612   c  and a fourth edge  1612   d  between the first edge  1612   a  and the second edge  1612   b . The first gap D 11  is the distance between the third edge  1612   c  and the adjacent edge of the first electrode  1512 , and the second gap D 21  is the distance between the fourth edge  1612   d  and the adjacent edge of the first electrode  1512 . 
     In addition, as shown in  FIG. 4 , in a direction perpendicular to the first extension direction Dir 1 , the first electrode  1511  of the first pixel unit Px 1  corresponding to the first outline  2631  has a fifth width W 5 , the first electrode  1511  has a sixth width W 6  between the first outline  2631  and the second outline  1611 , and the sixth width W 6  is greater than the fifth width W 5 . In this case, the width of the first electrode  1511  is gradually increased from the first outline  2631  to the second outline  1611 . Thus, the heat generated at the first electrode  1511  between the first outline  2631  and the second outline  1611  can be decreased. In another embodiment of the present disclosure, the first electrode  1511  of the first pixel unit Px 1  corresponding to the second outline  1611  has a seventh width W 7  in the direction perpendicular to the first extension direction Dir 1 , and the seventh width W 7  is greater than the sixth width W 6 . 
     Embodiments 2 and 3 
       FIG. 6  and  FIG. 7  are respectively top views showing a part of a display region of an OLED display device of Embodiments 2 and 3, wherein  FIG. 6  and  FIG. 7  are respectively a normal direction view of the first substrate shown in  FIG. 2 . Herein, the structure of the OLED display devices of Embodiments 2 and 3 are similar to that of Embodiment 1, except the shapes and the positions of the first electrode, the light emitting regions and the via holes. 
     A display device made as described in any of the embodiments of the present disclosure as described previously may be integrated with a touch panel to form a touch display device. Moreover, a display device or touch display device made as described in any of the embodiments of the present disclosure as described previously may be applied to any electronic devices known in the art that need a display screen, such as displays, mobile phones, laptops, video cameras, still cameras, music players, mobile navigators, TV sets, and other electronic devices that display images. 
     Although the present disclosure has been explained in relation to its embodiment, it is to be understood that many other possible modifications and variations can be made without departing from the spirit and scope of the disclosure as hereinafter claimed.