Patent Publication Number: US-2023146528-A1

Title: Display substrate, display panel and display device

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application claims priority to Chinese Patent Application No. 202010074996.6 filed in China on Jan. 22, 2020, which is incorporated herein by reference in its entirety. 
     TECHNICAL FIELD 
     The present disclosure relates to the technical field of display, in particular to a display substrate, a display panel and a display device. 
     BACKGROUND 
     Some display panels need to be provided with a light sensor, for example, a light sensor for detecting the display brightness of a display panel may be provided, and these light sensors may occupy an opening area of the display panel, which may cause decrease of the opening area of the display panel, accordingly may cause decrease of the resolution of the display panel and may affect the display effect. 
     SUMMARY 
     Embodiments of the present disclosure provide a display substrate, a display panel, and a display device to solve the problem that a light sensor may cause a decrease of resolution of the display panel, affecting the display effect. 
     In a first aspect, the embodiments of the present disclosure provide a display substrate, including a substrate, a plurality of sub-pixels located on the substrate, a plurality of driving circuits and a plurality of light sensors. An orthographic projection of the light sensor on the substrate is within the range of the orthographic projection of the driving circuit on the substrate. 
     Optionally, a detection range of each of the light sensors corresponds to a plurality of the sub-pixels, and the light sensors are configured to detect the brightness of the corresponding sub-pixels. 
     Optionally, an orthographic projection of each of the light sensors on the substrate is within a range of an orthographic projection of the driving circuit of the plurality of sub-pixels corresponding to the light sensors on the substrate. 
     Optionally, the plurality of sub-pixels corresponding to each of the light sensors are respectively arranged on two opposite sides of the light sensor in a first direction parallel to the substrate. 
     Optionally, the plurality of light sensors includes a first light sensor and a second light sensor, and the driving circuit includes a first driving circuit and a second driving circuit; 
     the first driving circuit is configured to drive a first sub-pixel group of the plurality of sub-pixels, and the second driving circuit is configured to drive a second sub-pixel group of the plurality of sub-pixels except the first sub-pixel group; the first light sensor is configured to detect the brightness of the first sub-pixel group, and the second light sensor is configured to detect the brightness of the second sub-pixel group; 
     the orthographic projection of the first light sensor on the substrate is within the range of the orthographic projection of the first driving circuit on the substrate, the orthographic projection of the second light sensor on the substrate is within the range of the orthographic projection of the second driving circuit on the substrate. 
     Optionally, the first light sensor, the first sub-pixel group, the second light sensor, and the second sub-pixel group are arranged sequentially along the first direction. 
     Optionally, in the first direction, the first sub-pixel group is located between the first light sensor and the second light sensor, the second sub-pixel group is located on a side, away from the first sub-pixel group, of the second light sensor, the second light sensor is located between the first sub-pixel group and the second sub-pixel group. 
     Optionally, the plurality of sub-pixels in the first sub-pixel group are arranged in a second direction, and the plurality of sub-pixels in the second sub-pixel group are arranged in the second direction, wherein the second direction is parallel to the substrate and perpendicular to the first direction. 
     Optionally, the light sensor is electrically connected to the driving circuit via a via-hole on the display substrate, the orthographic projection of the via-hole opened on the substrate is within the range of the orthographic projection of the driving circuit on the substrate. 
     Optionally, the orthographic projection of the via-hole on the substrate is within the range of the orthographic projection of the light sensors on the substrate. 
     Optionally, the sub-pixels of different colors are made by a single patterning process. 
     In a second aspect, embodiments of the present disclosure also provide a display panel including a display substrate as described in any of the above. 
     In a third aspect, embodiments of the present disclosure also provide a display device including a display panel as described above. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In order that the manner in which the embodiments of the present disclosure are recited in detail, a brief description of the drawings that accompany the detailed description of the embodiments of the present disclosure is provided below. It is to be understood that the appended drawings are illustrative of only some embodiments of the present disclosure. For a person of ordinary skill in the art, other figures can also be obtained according to these figures without involving any inventive effort. 
         FIG.  1    is a schematic structural diagram of a display substrate provided by embodiments of the present disclosure; 
         FIG.  2 A  is a schematic structural diagram of a display substrate in the related art; 
         FIG.  2 B  is another schematic structural diagram of a display substrate in the related art; 
         FIG.  3 A  is another schematic structural diagram of a display substrate provided by an embodiment of the present disclosure; 
         FIG.  3 B  is another schematic structural diagram of a display substrate provided by an embodiment of the present disclosure; and 
         FIG.  3 C  is another schematic structural diagram of a display substrate provided by an embodiment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     The technical solution of embodiments of the present disclosure will now be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all embodiments of the disclosure are shown. Based on the embodiments of the present disclosure, all other embodiments obtained by a person of ordinary skill in the art without inventive effort fall within the scope of protection of this disclosure. 
     Embodiments of the present disclosure provide a display substrate. 
     In one embodiment of the present disclosure, as shown in  FIGS.  1 ,  3 A and  3 B , the display substrate includes a substrate, a plurality of sub-pixels  10  located on the substrate, a driving circuit  20  and a plurality of light sensors  30 . 
     The light sensors  30  in the present embodiment are configured to detect the intensity of light, and specifically, for example, may be configured to detect the display brightness of the sub-pixels  10  and perform brightness compensation on the display brightness of the sub-pixels  10  according to a detection result, and may also be used as a scene such as fingerprint recognition. Structures of the light sensors  30  can be referred to the related art, and their specific structure are not limited in this embodiment. 
     The driving circuit  20  refers to various circuit structures on the display substrate, may refer to, for example, a transistor that controls the sub-pixels  10 , and specifically may be a thin film transistor (TFT), etc. or a thin film transistor that controls the light sensors  30 , etc. These driving circuits  20  occupy a certain opening area. 
     A bottom-emitting display substrate is further described in this embodiment. 
     As shown in  FIG.  1   , the display substrate in one embodiment includes a substrate  101 , a shield  102 , a buffer  103  and an active  104 , a gate insulation layer (GI)  105 , a gate layer (Gate)  106 , a dielectric layer (ILD)  107 , a first source-drain electrode structure (SD1)  108 , a second source-drain electrode structure (SD2)  109 , an organic insulation layer (sog)  110 , a first passivation layer (PVX1)  111 , a second passivation layer (PVX2)  112 , a third passivation layer (PVX3)  113 , a PIN type photodiode  114  used as the light sensors  30 , a first transparent electrode layer (ITO1)  115 , A second transparent electrode layer (ITO2)  116 , a filling structure (RESIN)  117 , a pixel definition layer (PDL)  118 , an electroluminescent layer (EL)  119  and a third electrode layer  120 , which are arranged on the substrate. 
     It is to be understood that adaptive adjustment can be made to the structure of the display substrate in this embodiment, and the structure of the display substrate is not further limited in this embodiment. 
     Referring to  FIGS.  2 A and  2 B , a display substrate in the related art is shown in  FIGS.  2 A and  2 B . As shown in  FIGS.  2 A and  2 B , the PIN type photodiode  114  used as the light sensors  20  and the driving circuit  20  are arranged in a staggered way, so that a large opening area is occupied. 
     Since the driving circuit  20  is located in an area outside the opening area, the orthographic projection of the light sensors  30  on the substrate is located within the range of the orthographic projection of the driving circuit  20  on the substrate by adjusting the position of the light sensors  30 , which can reduce the occupation of the opening area of the display panel and help to improve the resolution of the display panel. 
     Thus, according to the technical solution of the embodiment of the present disclosure, the orthographic projection of the light sensors  30  on the substrate is controlled to be within the range of the orthographic projection of the driving circuit  20  on the substrate, which can reduce the occupation of the opening area of the pixel, help to save the pixel space, improve the resolution of the display panel, and then contribute to improving a display effect of the display panel. 
     Optionally, the detection range of each light sensor  30  corresponds to a plurality of sub-pixels  10 , and is configured to detect the brightness of the corresponding sub-pixel  10 . 
     It should be understood that the larger the area of the light sensors  30 , the higher the signal-to-noise ratio of a detection result of the light sensors  30  and the higher the detection accuracy of the light sensors  30 . In this embodiment, the brightness of the plurality of sub-pixels  10  is detected by using one light sensor  30 . With respect to providing a larger number of sensors, it is possible to reduce the required driving circuit  20  and actually increase the detection area of the light sensors  30 , which is advantageous for improving the accuracy of the detection result. 
     More specifically, the orthographic projection of the light sensors  30  onto the substrate is within the range of the orthographic projection of the driving circuit  20  of the plurality of sub-pixels  10  corresponding to the light sensors  30  onto the substrate. 
     Optionally, the plurality of sub-pixels  10  corresponding to the light sensors  30  are respectively arranged on two opposite sides of the light sensors  30 , in a first direction parallel to the substrate. 
     As shown in  FIG.  3 A , taking eight sub-pixels  10  corresponding to each light sensor  30  as an example, four sub-pixels  10  are arranged on each side of the light sensor  30 , so that the light sensor  30  actually occupies an area corresponding to the driving circuit  20  of the eight sub-pixels  10 . This makes space more available. 
     Optionally, in a direction parallel to the substrate, the plurality of sub-pixels  10  corresponding to the same light sensor  30  are arranged on the same side of the light sensor  30 , and the light sensor  30  and a sub-pixel group  10  corresponding to the same light sensor  30  are arranged at intervals in sequence. 
     As shown in  FIG.  3 B , taking four sub-pixels  10  corresponding to each light sensor  30  as an example to explain, the four sub-pixels  10  are in a group and all are arranged on the same side of the light sensor  30 , and each sub-pixel group  10  and the light sensor  30  are arranged on the display substrate at intervals in sequence in the form of a sub-pixel group  10 , a light sensor  30 , a sub-pixel group  10 , a light sensor  30 , etc., so that local sub-pixels  10  can be avoided to be too concentrated, and thus the distribution of the sub-pixels  10  can be more dispersed, which helps to improve the uniformity of display. 
     Specifically, as shown in  FIG.  3 C , the plurality of light sensors  30  include a first light sensor  301  and a second light sensor  302 , and the driving circuit  20  includes a first driving circuit  201  and a second driving circuit  202 . 
     The first driving circuit  201  is configured to drive a first sub-pixel group  101  of the plurality of sub-pixels, and the second driving circuit  202  is configured to drive a second sub-pixel group  102  of the plurality of sub-pixels except the first sub-pixel group  101 ; the first light sensor  301  is arranged to detect the brightness of the first sub-pixel group  101  and the second light sensor  302  is arranged to detect the brightness of the second sub-pixel group  102 . 
     The orthographic projection of the first light sensor  301  on the substrate is within the range of the orthographic projection of the first driving circuit  201  on the substrate, the orthographic projection of the second light sensor  302  onto the substrate is within the range of the orthographic projection of the second driving circuit  202  onto the substrate. 
     In the first direction, the first light sensor  301 , the first sub-pixel group  101 , the second light sensor  302 , and the second sub-pixel group  102  are sequentially arranged. 
     In the first direction, the first sub-pixel group  101  is located between the first light sensor  301  and the second light sensor  302 , and the second sub-pixel group  102  is located on a side, away from the first sub-pixel group  101 , of the second light sensor  302 , the second light sensor  302  is located between the first sub-pixel group  101  and the second sub-pixel group  102 . 
     The plurality of sub-pixels in the first sub-pixel group  101  are arranged along a second direction, and the plurality of sub-pixels in the second sub-pixel group  102  are arranged along the second direction, wherein the second direction is parallel to the substrate and perpendicular to the first direction. 
     Optionally, the light sensor  30  is electrically connected to the driving circuit  20  through a via-hole  40  opened on the display substrate, the orthographic projection of the via-hole  40  on the substrate is within the range of the orthographic projection of the driving circuit  20  on the substrate. 
     As shown in  FIG.  2 B , in the related art, in order to electrically connect the light sensors  30  to the driving circuit  20 , a connection line needs to occupy a certain space, and in this embodiment, since the orthographic projection of the light sensors  30  onto the substrate is within the range of the orthographic projection of the driving circuit  20  onto the substrate, the via-hole  40  can be placed within a corresponding range of the driving circuit  20 , which helps to save space. Further, the orthographic projection of the via-hole  40  onto the substrate is within the range of the orthographic projection of the light sensors  30  onto the substrate, which can further facilitate the electrical connection of the light sensors  30 . 
     Further, sub-pixels  10  of different colors are manufactured by a single patterning process. 
     As shown in  FIG.  3 A  and  FIG.  3 B , it should be understood that the structure of each sub-pixel  10  is quite different because the connection line between the light sensors  30  and the driving circuit  20  occupies a certain space in a design scheme of the related art. Therefore, sub-pixels  10  of different colors need to be made respectively, for example, for a display substrate including sub-pixels  10  of three colors of RGB (red, green and blue), sub-pixels  10  of different colors need to be made through three times of mask process (mask exposure process); however, in the technical solution of the present embodiment, since the wiring via-hole  40  is located in the range of the orthographic projection of the driving circuit  20  on the substrate, the structure of each sub-pixel  10  is not affected by the connection line between the light sensors  30  and the driving circuit  20 ; therefore, fabrication of the three color sub-pixels  10  can be accomplished by a single patterning process, which helps to save process steps and costs. 
     After testing, the resolution of a display panel is about 94 PPI (the number of pixels per inch, or called pixel density). After the light sensors  30  are added, because the light sensors  30  need to occupy a certain opening area, based on the design method in the related art, the resolution of the display panel is about 80 PPI, and after the technical solution proposed in the present application is adopted, the resolution of display panel is about 88 PPI, which can effectively improve the resolution of a display panel with respect to the related art. 
     At the same time, in the design scheme of the related art, the area of the light sensor  30  corresponding to each sub-pixel  10  is about 1300 square microns, and after the technical solution proposed in the present application is adopted, the area of the light sensor  30  corresponding to each sub-pixel  10  is increased to 2100 square microns, and the area of the light sensor  30  corresponding to each sub-pixel  10  is increased, which helps to improve the signal-to-noise ratio of a signal collected by the light sensors  30 . 
     Embodiments of the present disclosure also provide a display panel and a display device, wherein the display panel includes a display substrate as described in any of the above, and the display device includes the display panel. 
     Since the technical solution of the present embodiment includes all the technical solutions of the above-mentioned display substrate embodiments, at least all the above-mentioned technical effects can be achieved, and description thereof will not be repeated here. 
     The above embodiments are merely specific implementation modes of the present disclosure, but the scope of protection of the present disclosure is not limited thereto, and any modification and substitution being apparent to those skilled in the art without departing from the technical scope of the present disclosure shall covered by the scope protection of the present disclosure. Accordingly, the scope of protection of the present disclosure is as set forth in the claims.