Patent Publication Number: US-2023161189-A1

Title: Display device

Description:
FIELD OF INVENTION 
     The present disclosure relates to the field of display technology, and particularly relates to a display device. 
     BACKGROUND OF INVENTION 
     Currently, mainstream display panels include liquid crystal display (LCD) panels and organic light emitting diode (OLED) displays. Wherein, LCD is a passive light emitting technology that needs irradiation of a backlight module to make a liquid crystal cell realize control of brightness or darkness of light. 
     As illustrated in  FIG.  1   , in an LCD in-display sensing solution, collimation backlights are mainly used. Part of display light having a certain collimation characteristic is reflected at a crest of a finger  20 ′ and then enters into a glass cover plate  100  to form reflected light  101 . The reflected light  101  has an angle distribution which is same as the display light, that is, has a smaller angle distribution. In a process of collecting fingerprint signals, reflected light of fingerprints of a small angle region can be obtained, thereby having a better signal-to-noise ratio. Another part of light  102  directly penetrates into an air surface from a surface of the cover plate  100 . Reflection of the light at this position is not full diffuse scattering, that is, a main direction of the reflected light and an angle distribution of incident light have a certain similarity. However, overall the incident light is dispersed, and noise signals are presented in the process of collecting fingerprint signals. It can be understood that excessive collimation will limit viewing angles of displays, that is, viewing angles are reduced while improving signal-to-noise ratios of current displays. 
     Therefore, it is necessary to provide a display device to solve a problem existing in the prior art. 
     SUMMARY OF INVENTION 
     A purpose of the present disclosure is to provide a display device, which is able to improve signal-to-noise ratios and simultaneously enlarges viewing angles. 
     In order to solve the technical problem mentioned above, the present disclosure provides a display device, which includes: 
     a backlight module, wherein a reverse prism structure is disposed on top of the backlight module; and 
     a display module disposed above the backlight module, wherein the display module includes a display panel and a sensor component, the sensor component is embedded in the display panel, the sensor component includes a plurality of sensors, a plurality of diffraction gratings are disposed on surfaces of the plurality of sensors, a grating direction of the plurality of diffraction gratings is perpendicular to a grating direction of the reverse prism structure, a material of the plurality of diffraction gratings is an inorganic material, the display panel includes a plurality of pixel units, and the plurality of sensors correspond to the plurality of pixel units. 
     The present disclosure further provides a display device, including: 
     a backlight module, wherein a reverse prism structure is disposed on top of the backlight module; and 
     a display module disposed above the backlight module, wherein the display module includes a display panel and a sensor component, the sensor component is embedded in the display panel, the sensor component includes a plurality of sensors, a plurality of diffraction gratings are disposed on surfaces of the plurality of sensors, a grating direction of the plurality of diffraction gratings is perpendicular to a grating direction of the reverse prism structure. 
     The display device of the present disclosure includes a backlight module, wherein a reverse prism structure is disposed on top of the backlight module; and a display module disposed above the backlight module, wherein the display module includes a display panel and a sensor component, the sensor component is embedded in the display panel, the sensor component includes a plurality of sensors, a plurality of diffraction gratings are disposed on surfaces of the plurality of sensors, and a grating direction of the plurality of diffraction gratings is perpendicular to a grating direction of the reverse prism structure; therefore, a reduction of display viewing angles is prevented while improving the signal-to-noise ratios, thereby and improving display effect and accuracy of signals. 
    
    
     
       DESCRIPTION OF DRAWINGS 
         FIG.  1    is a light path schematic diagram of light propagation of an under-screen sensing solution. 
         FIG.  2    is a structural schematic diagram of a display device of the present disclosure. 
         FIG.  3    is a first top view of the display device of the present disclosure. 
         FIG.  4    is a second top view of the display device of the present disclosure. 
         FIG.  5    is a light path schematic diagram of light propagation of the display device of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     The descriptions of embodiments below refer to accompanying drawings in order to illustrate certain embodiments which the present disclosure can implement. The directional terms of which the present disclosure mentions, for example, “top”, “bottom”, “front”, “rear”, “left”, “right”, “inside”, “side”, etc., only refer to directions of the accompanying figures. Therefore, the used directional terms are for illustrating and understanding the present disclosure, but not for limiting the present disclosure. In the figures, units with similar structures are indicated by the same reference numerals. 
     Please refer to  FIG.  2    to  FIG.  5   ,  FIG.  2    is a structural schematic diagram of a display device of the present disclosure. 
     As illustrated in  FIG.  2   , the display device of the present disclosure includes a backlight module  10  and a display module  200 . 
     A reverse prism structure  14  is disposed on top of the backlight module  10 , thereby making an outgoing light angle of an angle of the prism perpendicular to a direction of the reverse prism structure be compressed. In an embodiment, sequentially from bottom to top, the backlight module  10  includes a reflective sheet  11 , a light guide plate  12 , a diffusion sheet  13 , and the reverse prism structure  14 . That is, the reverse prism structure  14  is located above the diffusion sheet  13 . Furthermore, the reverse prism structure  14  constitutes a one-dimensional backlight structure. 
     In addition, the backlight module  10  can further include a light source  15 . The light source  15  is disposed on a side of the light guide plate  12 . In an embodiment, in order to make the angles of the outgoing light compress, a half-intensity angle of light emitted from the backlight module  10  ranges from 10 degrees to 20 degrees. Preferably, the half-intensity angle ranges from 10 degrees to 15 degrees. 
     The display module  200  is disposed above the backlight module  10 . The display module  200  includes a display panel and a sensor component  40 . 
     Furthermore, a sectional structure of the display panel can include a lower polarizer  21 , an array substrate  22 , a liquid crystal layer  24 , a color film substrate  25 , and a top polarizer  26 , and of course, can also include a cover plate. The color film substrate  25  is located above the array substrate  22 . The color film substrate  25  includes a plurality of color resists  251  and a plurality of black matrices  252 . Combined with  FIG.  3    and  FIG.  4   , the display panel includes a plurality of pixel units  30 . The pixel units include a plurality of subpixels  31  to subpixels  33 , for example, red subpixels, green subpixels, and blue subpixels are included. 
     Combined with  FIG.  3    and  FIG.  4   , the sensor component  40  is embedded in the display panel. In an embodiment, in order to improve the signal-to-noise ratios, the sensor component  40  can be located between the array substrate  22  and the liquid crystal layer  24 . In other embodiments, the sensor component  40  is located between the array substrate  22  and the lower polarizer  21 , and of course, the sensor component  40  can also be located on an inner surface of a lower base substrate of the color film substrate  25 , or the sensor component  40  is located between the color film substrate  25  and the top polarizer  26 . It can be understood that configuration manners of the sensor component  40  are not limited thereto. 
     Combined with  FIG.  3    and  FIG.  4   , the sensor component  40  includes a plurality of sensors  41 . A plurality of diffraction gratings  411  are disposed on surfaces of the plurality of sensors  41 . Furthermore, the diffraction gratings  411  can be manufactured in a direction of the sensors  41  facing reflected light signals (such as fingerprints) by a nano-imprinting manner. Furthermore, a grating direction of the plurality of diffraction gratings  411  is perpendicular to a grating direction of the reverse prism structure  14 . 
     In an embodiment, in order to further enlarge the display viewing angles, a material of the diffraction gratings  411  is an inorganic material. Furthermore, the material of the plurality of diffraction gratings  411  can include at least one of SiOx, SiNx, or TaOx. In an embodiment, a period of the plurality of diffraction gratings  411  ranges from 100 nm to 1000 nm. In an embodiment, a duty cycle of the plurality of diffraction gratings  411  ranges from 0.3 to 0.8. 
     In an embodiment, the sensors  41  can correspond to the pixel units  30 . As illustrated in  FIG.  3   , the sensors  41  are parallel to the subpixels  31  to subpixel  33 . As illustrated in  FIG.  4   , the sensors  41  are perpendicular to the subpixels  31  to subpixel  33 . 
     Preferably, positions of the plurality of sensors  41  correspond to positions of the plurality of black matrices  252  located in a first direction, and the first direction is parallel to a plurality of scanning lines. That is, the sensors  41  overlap with the positions of the black matrices in a direction of scanning lines, thereby preventing an aperture ratio from being affected. 
     In an embodiment, the sensors  41  include at least one of face recognition sensors, distance sensors, light sensors, or three-dimensional sensors. 
     As illustrated in  FIG.  5   , when incident light a with a certain angle distribution passes through the diffraction gratings  411 , by diffraction effect of the diffraction gratings  411 , light of certain diffraction levels are made to compress into small-angle lights b, and light with other angles is reflected, thereby having collimation-like effect. 
     Taking the sensor as a fingerprint sensor as an example, because the reverse prism structure is used in the backlight module, the reverse prism structure makes reflected light of fingerprints have a feature of near collimation in one direction, meanwhile prevents full compression of the display viewing angles, and has anti-peep effect in the direction. Because the diffraction gratings are disposed on the surfaces of the fingerprint sensors, and the grating direction of the diffraction gratings is perpendicular to a grating direction of the reverse prism structure, the light entering the surfaces of the diffraction gratings by reflection has an angle filter effect in another direction. Because the diffraction gratings only have patterning structure on the surfaces of the sensors, the display viewing angles in the direction are not affected, that is, the light entering into the sensors by reflection constitute collimation-like structures on two dimensions by the structures mentioned above, which prevents a reduction of display viewing angles while improving the signal-to-noise ratio of the fingerprint signals. That is, a better balance is obtained between the signal-to-noise ratios of the fingerprint signals and the display viewing angles, which improves display effect and accuracy of fingerprint signals, and other signals are similar to this. 
     The display device of the present disclosure includes a backlight module, wherein a reverse prism structure is disposed on top of the backlight module; and a display module disposed above the backlight module, wherein the display module includes a display panel and a sensor component, the sensor component is embedded in the display panel, the sensor component includes a plurality of sensors, a plurality of diffraction gratings are disposed on surfaces of the plurality of sensors, and a grating direction of the plurality of diffraction gratings is perpendicular to a grating direction of the reverse prism structure. Therefore, a reduction of display viewing angles is prevented while improving the signal-to-noise ratios, thereby improving display effect and accuracy of signals. 
     In summary, although the present disclosure has disclosed the preferred embodiments as above, however the above-mentioned preferred embodiments are not to limit to the present disclosure. A person skilled in the art can make any change and modification, therefore the scope of protection of the present disclosure is subject to the scope defined by the claims.