DISPLAY PANEL

A display panel includes a first display area. The first display area includes a display substrate and an optical layer. The display substrate includes a pixel defining layer and a cathode layer disposed on the pixel defining layer. The pixel defining layer includes a plurality of pixel openings and a plurality of supporting portions each disposed between two adjacent pixel openings. A thickness of a part of the cathode layer on each of the pixel opening is greater than a thickness of a part of the cathode layer on each of the supporting portions. The optical layer is disposed on the cathode layer and includes a plurality of first optical structures corresponding to the supporting portions. Each of the first optical structures includes a first surface close to the cathode layer, a second surface opposite to the first surface, and a side surface that is a total reflective surface.

FIELD OF INVENTION

The present disclosure relates to the technical field of display, and particularly to a display panel.

BACKGROUND

Organic light-emitting diode (OLED) display technology has received more and more attention from scientific researchers, and has been widely applied in the field of display such as mobile phones, flat panels, and televisions. With the rapid development of display devices, users have higher and higher requirements for screen-to-body ratios of display devices, so that large-size and high-resolution full-screen display devices become a future development direction.

In the prior art, in order to increase screen-to-body ratios as much as possible, optical components such as front cameras and facial recognition devices are usually disposed under screens. However, in a current OLED full-screen display device, a cathode electrode is disposed on an entire surface. The cathode electrode has a low light transmittance, so that optical components disposed under a screen cannot receive sufficient light signals, which affects normal operations of the optical components.

SUMMARY OF DISCLOSURE

The present disclosure provides a display panel that can solve the problem that optical components disposed under screens cannot receive sufficient light signals, which affects normal operations of the optical components.

In order to solve the aforementioned problem, the present disclosure provides the following technical solutions.

The present disclosure provides a display panel comprising a first display area and a second display area surrounding the first display area. A light transmittance of the first display area is greater than a light transmittance of the second display area. The first display area comprises:a display substrate comprising a pixel defining layer and a cathode layer disposed on the pixel defining layer, wherein the pixel defining layer comprises a plurality of pixel openings spaced apart from each other and a plurality of supporting portions each disposed between two adjacent pixel openings, and a thickness of a part of the cathode layer on each of the pixel openings is greater than a thickness of a part of the cathode layer on each of the supporting portions; andan optical layer disposed on a side of the cathode layer away from the pixel defining layer, and comprising a plurality of first optical structures each correspondingly disposed between two adjacent pixel openings, wherein each of the first optical structures comprises a first surface close to the cathode layer, a second surface opposite to the first surface, and a side surface that is a total reflective surface.

Optionally, in some embodiments, the optical layer further comprises at least two optical sub-layers with different refractive indices, and at least one of the at least two optical sub-layers forms the first optical structures.

Optionally, in some embodiments, the refractive indices of the at least two optical sub-layers decrease sequentially from a side close to the display substrate to a side away from the display substrate. A cross-sectional width of a side of each of the first optical structures away from the display substrate is greater than or equal to a cross-sectional width of a side of each of the first optical structures close to the display substrate.

Optionally, in some embodiments, the optical layer further comprises a plurality of second optical structures corresponding to the pixel openings. The second optical structures are disposed in a same layer as the first optical structures. Each of the second optical structures comprises a first surface close to the cathode layer, a second surface opposite to the first surface, and a side surface that is a total reflective surface.

Optionally, in some embodiments, a cross-sectional width of a side of each of the second optical structures away from the display substrate is greater than or equal to a cross-sectional width of a side of each of the second optical structures close to the display substrate.

Optionally, in some embodiments, the first optical structures and/or the second optical structures comprise at least two of the at least two optical sub-layers. One optical sub-layer on the side away from the display substrate covers one optical sub-layer on the side close to the display substrate. The at least two optical sub-layers in the first optical structures and/or the second optical structures have a same cross-sectional shape in a direction perpendicular to the display substrate.

Optionally, in some embodiments, the cathode layer comprises a plurality of first cathode portions corresponding to the pixel openings and a plurality of second cathode portions corresponding to the supporting portions, and a thickness of the first cathode portions is greater than a thickness of the second cathode portions.

Optionally, in some embodiments, the display substrate further comprises a plurality of anode electrodes, a first auxiliary layer, an organic light-emitting layer, a second auxiliary layer, and a cathode suppression layer. The anode electrodes are disposed corresponding to the first cathode portions. The first auxiliary layer is disposed on a side of each of the anode electrodes close to the cathode layer. The organic light-emitting layer is disposed on a side of the first auxiliary layer close to the cathode layer. The second auxiliary layer is disposed on a side of the organic light-emitting layer close to the cathode layer. The cathode suppression layer is disposed on each of the supporting portions. A thickness of the cathode suppression layer is less than a thickness of the cathode layer. An adhesion force between the cathode suppression layer and the cathode layer is less than an adhesion force between the cathode layer and the second auxiliary layer. The cathode suppression layer is made of a transparent material.

Optionally, in some embodiments, an orthographic projection of the cathode suppression layers on the optical layer is separated from an orthographic projection of the anode electrodes on the optical layer.

Optionally, in some embodiments, when the cross-sectional width of each of the first optical structures on the side away from the display substrate is greater than or equal to the cross-sectional width of each of the first optical structures on the side close to the display substrate, an orthographic projection of the first optical structures on the display substrate overlaps with the cathode suppression layers.

Optionally, in some embodiments, sides of the first optical structures close to the cathode suppression layers are bottoms, and a boundary of the bottom of each of the first optical structures corresponds to a boundary of one corresponding cathode suppression layer.

Optionally, in some embodiments, an orthographic projection of the second optical structures on the display substrate overlaps with the first cathode portions.

Optionally, in some embodiments, a width of the pixel openings is L, and a height of the pixel openings is H. An included angle between the side surface and the first surface of each of the first optical structures is a first included angle, and an included angle between the side surface and the first surface of each of the second optical structures is a second included angle. The first included angle and the second included angle are both greater than a threshold angle and less than or equal to 90°, and the threshold angle is arctan(H/L)*180°/π.

Optionally, in some embodiments, the first included angle is equal to the second included angle.

Optionally, in some embodiments, a boundary of a bottom of each of the second optical structures close to the cathode layer is located between a boundary of one corresponding pixel opening and a boundary beyond the boundary of the corresponding pixel opening by a predetermined distance, and the predetermined distance is a vertical distance from the pixel defining layer to the optical layer divided by a tangent value of the threshold angle.

Optionally, in some embodiments, the refractive indices of the at least two optical sub-layers increase sequentially from a side close to the display substrate to a side away from the display substrate. A cross-sectional width of a side of each of the first optical structures away from the display substrate is less than or equal to a cross-sectional width of a side of each of the first optical structures close to the display substrate.

Optionally, in some embodiments, the cathode layer comprises a plurality of first cathode portions corresponding to the pixel openings and a plurality of second cathode portions corresponding to the supporting portions, and a thickness of the first cathode portions is greater than a thickness of the second cathode portions.

Optionally, in some embodiments, the display substrate further comprises a plurality of anode electrodes, a first auxiliary layer, an organic light-emitting layer, a second auxiliary layer, and a cathode suppression layer. The anode electrodes are disposed corresponding to the first cathode portions. The first auxiliary layer is disposed on a side of each of the anode electrodes close to the cathode layer. The organic light-emitting layer is disposed on a side of the first auxiliary layer close to the cathode layer. The second auxiliary layer is disposed on a side of the organic light-emitting layer close to the cathode layer. The cathode suppression layer is disposed on each of the supporting portions. A thickness of the cathode suppression layer is less than a thickness of the cathode layer. An adhesion force between the cathode suppression layer and the cathode layer is less than an adhesion force between the cathode layer and the second auxiliary layer. The cathode suppression layer is made of a transparent material.

Optionally, in some embodiments, the first display area further comprises a plurality of light-transmitting areas each disposed between two adjacent pixel openings. When the cross-sectional width the side of each of the first optical structures away from the display substrate is less than or equal to the cross-sectional width of the side of each of the first optical structures close to the display substrate, an orthographic projection of each of the first optical structures on the display substrate is located between one of the pixel openings and one of the light-transmitting areas.

Optionally, in some embodiments, sides of the first optical structures close to the cathode suppression layers are bottoms, a side of the bottom of each of the first optical structures close to one adjacent pixel opening corresponds to a side of the adjacent pixel opening, and a side of the bottom of each of the first optical structures close to one adjacent light-transmitting area corresponds to a side of the adjacent cathode suppression layer.

In the display panel provided by the present disclosure, the cathode layer is patterned so that a part of the cathode layer correspondingly disposed between the pixel openings is thinner or there is no cathode layer deposited, which greatly improves a light transmittance of the first display area. Furthermore, the optical layer is disposed above a light-emitting surface of the display substrate. The optical layer comprises the first optical structures each disposed between two adjacent pixel openings. The first optical structures can reflect more external light into the first display area of the display panel, thereby further increasing an amount of light incident in the first display area. Therefore, optical components disposed in the first display area can receive sufficient light signals, thereby improving performances of the components.

DETAILED DESCRIPTION

Technical solutions in embodiments of the present disclosure will be clearly and completely described below in conjunction with accompanying drawings in the embodiments of the present disclosure. It is apparent that the described embodiments are merely a part of the embodiments of the present disclosure and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present disclosure without creative labor are within claimed scope of the present disclosure. In addition, it should be understood that specific embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention. In the present disclosure, unless otherwise stated, directional terms used herein specifically indicate directions of the accompanying drawings. For example, directional terms “upper” and “lower” generally refer to upper and lower positions of a device in actual use or working conditions, and directional terms “inside” and “outside” refer to positions relative to a profile of the device.

Reference numerals and/or letters may be repeated in different examples of the present disclosure. Such repetitions are for simplicity and clarity, which per se do not indicate relations among the discussed embodiments and/or settings.

The following embodiments of the present disclosure can solve the problem that optical components disposed under screens cannot receive sufficient light signals, which affects normal operations of the optical components.

Please refer toFIG.1, the present disclosure provides a display panel comprising a first display area11and a second display area12. The second display area12surrounds the first display area11. The first display area11may be disposed at any position on the display panel.

The display panel is a full-screen display panel. The first display area11is provided with a plurality of first sub-pixels13. The second display area12is provided with a plurality of second sub-pixels14.

It should be noted that the first display area11is a function additional area. The first display area11is configured to display images, so that the display panel displays in full screen. The first display area11is also configured to install optical components such as a camera, an optical touch component, and a fingerprint recognition sensor, thereby improving user experience. The second display area12is a main display area. The second display area12is configured to display images.

In an embodiment, a light transmittance of the first display area11is greater than a light transmittance of the second display area12.

It is understandable that the light transmittance of the first display area11has a great influence on works of the optical components. The light transmittance of the first display area11is related to a layer structure of the first display area11. Taking a camera as an optical component as an example, the higher the light transmittance of the first display area11, the better the imaging quality of the camera when the camera is shooting.

Please refer toFIG.2toFIG.10, the first display area11of the display panel comprises a display substrate100and an optical layer200. The display substrate100has a light-emitting surface. The optical layer200is disposed above the light-emitting surface of the display substrate100.

The display substrate100comprises a pixel defining layer1031and a cathode layer1034disposed on the pixel defining layer1031. The pixel defining layer1031comprises a plurality of pixel openings1001spaced apart from each other and a plurality of supporting portions1031aeach disposed between two adjacent pixel openings1001. A thickness of a part of the cathode layer1034on each of the pixel openings1001is greater than a thickness of a part of the cathode layer1034on each of the supporting portions1031a. When the thickness of the part of the cathode layer1034on each of the supporting portions1031ais 0, that is, no cathode layer is deposited between any two corresponding pixel openings1001.

Furthermore, the first display area11further comprises a plurality of light-transmitting areas111each disposed between two adjacent pixel openings1001. The light-transmitting areas111are configured to allow external light to pass through the display panel to the optical components. The thickness of the part of the cathode layer1034on each of the pixel openings1001is greater than a thickness of a part of the cathode layer1034in each of the light-transmitting areas111.

Furthermore, the optical layer200comprises a plurality of first optical structures200aeach correspondingly disposed between two adjacent pixel openings1001. Each of the first optical structures200acomprises a first surface close to the cathode layer1034, a second surface opposite to the first surface, and a side surface200a′. The side surfaces200a′ of the first optical structures200aare total reflective surfaces.

In the present disclosure, a portion of the cathode layer1034in the first display area11is patterned, so that the part of the cathode layer1034on each of the supporting portions1031adisposed between two corresponding pixel openings1001is thinner or there is no cathode layer deposited, thereby improving the light transmittance of the first display area11. Furthermore, in the present disclosure, the optical layer200is disposed above the light-emitting surface of the display substrate100. In the optical layer200, light is totally reflected on the side surfaces200a′ of the first optical structures200a. Therefore, external light emitted to outsides of the light-transmitting areas111is reflected into the light-transmitting areas111through the side surfaces200a′ of the first optical structures200a, so as to further increase an amount of light incident in the first display area11. Therefore, the optical components disposed in the first display area11can receive sufficient light signals, thereby improving performances of the optical components.

Please refer to the following embodiments for details. It should be noted that a description order of the following embodiments is not intended to limit a preferred order of the embodiments.

First Embodiment

Please refer toFIG.2, in this embodiment, a first display area11of a display panel comprises a display substrate100and an optical layer200disposed above a light-emitting surface of the display substrate100. The optical layer200comprises a first optical sub-layer201and a second optical sub-layer202. The second optical sub-layer202is disposed on a side of the first optical sub-layer201away from a base substrate101. A refractive index of the first optical sub-layer201is greater than a refractive index of the second optical sub-layer202.

Exemplarily, the refractive index of the first optical sub-layer201is 1.5-2, for example, it may be 1.5, 1.7, 1.8, or 2. The refractive index of the second optical sub-layer202is 1-1.4, for example, it may be 1, 1.1, 1.2, 1.3, or 1.4.

In this embodiment, the first optical sub-layer201forms a plurality of first optical structures200a. The display substrate100comprises a pixel defining layer1031and a cathode layer1034disposed on the pixel defining layer1031. The pixel defining layer1031comprises a plurality of pixel openings1001spaced apart from each other and a plurality of supporting portions1031aeach disposed between two adjacent pixel openings1001. The first optical structures200aare correspondingly disposed on the supporting portions1031aeach disposed between two adjacent pixel openings1001.

In other embodiments, the first optical structures200amay be formed from the second optical sub-layer202. At this time, portions of the first optical sub-layer201corresponding to the first optical structures200aneed to be provided with recesses that match the first optical structures200a. The first optical structures200aare embedded in the recesses.

In an embodiment, the optical layer200is a transparent layer.

Please refer toFIG.3, in this embodiment, a second display area12of the display panel comprises the display substrate100and a touch layer300. The touch layer300is disposed above the light-emitting surface of the display substrate100. The touch layer300comprises a first insulating layer301, a second insulating layer302, a third insulating layer303, a plurality of touch electrodes304, and a plurality of touch electrode connecting wires305. The first insulating layer301is disposed on a surface of the display substrate100. The touch electrode connecting wires305are disposed on a side of the first insulating layer301away from the display substrate100. The second insulating layer302is disposed on sides of the touch electrode connecting wires305away from the display substrate100. The touch electrodes304are disposed on a side of the second insulating layer302away from the display substrate100. The third insulating layer303is disposed on sides of the touch electrodes304away from the display substrate100.

The display substrate100comprises the pixel defining layer1031and the cathode layer1034disposed on the pixel defining layer1031. The pixel defining layer1031comprises the pixel openings1001spaced apart from each other and the supporting portions1031aeach disposed between two adjacent pixel openings1001. Each of the touch electrodes304and the touch electrode connecting wires305is correspondingly disposed between two adjacent pixel openings1001. Each of portions of the second insulating layer302corresponding to the touch electrode connection wires305is provided with a via hole penetrating the second insulating layer302. When the touch layer300is a mutual capacitive touch layer, each of the touch electrodes304comprises a first electrode and a second electrode that form a mutual capacitance. Two adjacent first electrodes or two adjacent second electrodes are electrically connected by one corresponding touch electrode connection wire305through one corresponding via hole.

As shown inFIG.2andFIG.3, in this embodiment, the display substrate100comprises the base substrate101, a thin-film transistor (TFT) device layer102, an organic light-emitting display (OLED) device layer103, and a thin film encapsulation layer104.

The base substrate101may be a flexible base substrate. The flexible base substrate may be made of organic materials such as polyimide. The base substrate101may also be a rigid base substrate. For example, the rigid base substrate may be made of glass, metal, plastic, etc. The base substrate101may have a single-layer structure or a multi-layer structure.

The TFT device layer102is disposed above the base substrate101. The display substrate100further comprises a buffer layer105between the TFT device layer102and the base substrate101. The buffer layer105is made of silicon oxide or silicon nitride that can block water and oxygen. The TFT device layer102comprises an active layer1021, a first gate insulating layer1022covering the active layer1021, a plurality of gate electrodes1023disposed on a side of the first gate insulating layer1022away from the base substrate101, a second gate insulating layer1024covering the gate electrodes1023, a plurality of second gate electrodes1025disposed on a side of the second gate insulating layer1024away from the base substrate101, an interlayer dielectric layer1026covering the second gate electrodes1025, a plurality of source/drain electrodes1027disposed on a side of the interlayer dielectric layer1026away from the base substrate101, and a planarization layer1028covering the source/drain electrodes1027.

The OLED device layer103is disposed on a side of the TFT device layer102away from the base substrate101. The OLED device layer103comprises the pixel defining layer1031, a plurality of anode electrodes1032, a plurality of organic light emitting layers1033, and a cathode layer1034. The pixel defining layer1031defines the pixel openings1001. The organic light emitting layers1033are disposed corresponding to the pixel openings1001. The organic light emitting layers1033are disposed between the anode electrodes1032and the cathode layer1034. The anode electrodes1032are disposed on a side of the cathode layer1034away from the optical layer200.

The thin film encapsulation layer104is disposed on a side of the OLED device layer103away from the base substrate101. The thin film encapsulation layer104is configured to protect devices in the display panel from influence of water and oxygen, thereby prolonging a service life of the display panel. The thin film encapsulation layer104comprises a first inorganic layer1041, a first organic layer1042, and a second inorganic layer1043. The first organic layer1042is disposed between the first inorganic layer1041and the second inorganic layer1043. The first inorganic layer1041is disposed on a side of the first organic layer1042close to the base substrate101. The second inorganic layer1043is disposed on a side of the first organic layer1042away from the base substrate101.

A difference between a portion of the display substrate100in the first display area11and a portion of the display substrate100in the second display area12is as follows. In the second display area12, the cathode layer1034is disposed as a whole layer without patterning, that is, its thickness remains uniform. In the first display area11, the cathode layer1034is patterned to have different thicknesses. That is, the cathode layer1034comprises a plurality of first cathode portions1034acorresponding to the pixel openings1001and a plurality of second cathode portions (not shown) corresponding to the supporting portions1031a, and a thickness of the first cathode portions1034ais greater than a thickness of the second cathode portions.

In this embodiment, the portion of the cathode layer1034in the first display area11is patterned into the first cathode portions1034a, and the first cathode portions1034aare disposed corresponding to the pixel openings1001.

As shown inFIG.2, in this embodiment, the first display area11further comprises a plurality of light-transmitting areas111each disposed between two adjacent pixel openings1001. The light-transmitting areas111are configured to allow external light to pass through the display panel to optical components.

The display substrate100further comprises a plurality of first auxiliary layers (not shown) disposed between the anode electrodes1032and the organic light-emitting layers1033, and a plurality of second auxiliary layers (not shown) disposed between the organic light-emitting layers1033and the first cathode portions1034a. The first auxiliary layers may be hole transport layers. The second auxiliary layers may be electron transport layers.

The first display area11further comprises a plurality of cathode suppression layers1035. The cathode suppression layers1035are disposed on the support portions1031a. An orthographic projection of the cathode suppression layers1035on the optical layer200is separated from an orthographic projection of the anode electrodes1032on the optical layer200, that is, does not overlap with the orthographic projection of the anode electrodes1032on the optical layer200. Furthermore, an adhesion force between the cathode suppression layers1035and the cathode layer1034is less than an adhesion force between the cathode layer1034and the second auxiliary layers.

The cathode layer1034may be made of magnesium. The cathode suppression layers1035may be made of at least one of bis(2-methyl-8-hydroxyquinoline)-4-(p-phenylphenol)-aluminum (BAlq), 3-(4-biphenylyl)-4-phenyl-5-(4-tert-butylphenyl)-1,2,4-triazole (TAZ), and indium oxide (OTI). Magnesium has poor adhesion on BAlq, TAZ, and OTI. When magnesium is deposited to form the cathode layer1034, the cathode suppression layers1035suppress magnesium from forming films on the cathode suppression layers1035. Because the cathode suppression layers1035are made of a transparent material, a light transmittance of the first display area11is improved.

Furthermore, a boundary of each of the cathode suppression layers1035coincides with a boundary of one corresponding light-transmitting area111.

In an embodiment, a thickness of the cathode suppression layers1035is not greater than a thickness of the cathode layers1034.

As shown inFIG.2,FIG.4, andFIG.5, a first included angle α1between a side surface200a′ and a first surface of each of the first optical structures200ais 0° to 90°. For example, the first included angle α1is 15°, 30°, 45°, 60°, 70°, 80°, or 90°.

As shown inFIG.4, an orthographic projection of the first optical structures200aon the display substrate100overlaps with the cathode suppression layers1035. Specifically, sides of the first optical structures200aclose to the thin film encapsulation layer104are bottoms, and a boundary of each of the bottoms corresponds to a boundary of one corresponding cathode suppression layer1035. In a direction perpendicular to the display substrate100, a cross-sectional width w2 of a side of each of the first optical structures200aaway from the display substrate100is greater than a cross-sectional width w1 of a side of each of the first optical structures200aclose to the display substrate100. Because the refractive index of the second optical sub-layer202is greater than a refractive index of the first optical structures200a(that is, the first optical sub-layer), an interface (that is, the side surface200a′) between each of the first optical structures200aand the second optical sub-layer202is a total reflective surface. When external light enters the first optical structures200a, the external light directed to the side surfaces200a′ is totally reflected on inner surfaces of the side surfaces200a′, thereby changing a path of the external light. Therefore, the external light originally directed outside the light-transmitting areas111enters the light-transmitting areas111after being totally reflected, thereby increasing an amount of light incident in the light-transmitting areas111and increasing the light transmittance of the first display area11.

As shown inFIG.5, when the first included angle α1between the side surface200a′ and the first surface of each of the first optical structures200ais 90°, in the direction perpendicular to the display substrate100, the cross-sectional width w2 of the side of each of the first optical structures200aaway from the display substrate100is equal to the cross-sectional width w1 of the side of each of the first optical structures200aclose to the display substrate100. Because the external light is natural light, the external light can illuminate the side surfaces200a′ when the first included angle α1is 90°. When the external light enters the first optical structures200a, the external light directed to the side surfaces200a′ is totally reflected on inner surfaces of the side surfaces200a′, thereby changing the path of the external light. Therefore, the external light originally directed outside the light-transmitting areas111enters the light-transmitting areas111after being totally reflected, thereby increasing the amount of the light incident in the light-transmitting areas111and increasing the light transmittance of the first display area11.

Please refer toFIG.2toFIG.5. For convenience of production, the first display area11may share the first insulating layer301, the second insulating layer302, and the third insulating layer303in the second display area12. That is, the second optical sub-layer202and the third insulating layer303may be a same layer.

In an embodiment, a thickness of the optical layer200is 1 μm to 3.5 μm. A thickness of the first optical sub-layer201is 0.2 μm to 1.5 μm. A thickness of the second optical sub-layer202is 1 μm to 2 μm.

In an embodiment, the side surface200a′ of each of the first optical structures200ais an inclined surface or a curved surface.

Furthermore, when the side surface200a′ of each of the first optical structures200ais a curved surface, a radius of curvature of the curved surface is 1.5 μm to 5 μm.

Second Embodiment

Please refer toFIG.2,FIG.3, andFIG.6, a structure of a display panel of this embodiment is similar to a structure of the display panel of the first embodiment. This embodiment differs from the first embodiment in that an optical layer200of the display panel of this embodiment comprises a plurality of optical sub-layers with different refractive indices, and at least two of the optical sub-layers form first optical structures200a. Refractive indices of the optical sub-layers decrease sequentially from a side close to a display substrate100to a side away from the display substrate100. One optical sub-layer on the side away from the display substrate100covers one optical sub-layer on the side close to the display substrate100, and the at least two optical sub-layers in the first optical structures200ahave a same cross-sectional shape in a direction perpendicular to the display substrate100.

Please refer toFIG.6for details. A region shown inFIG.6is equivalent to a region A inFIG.2. For convenience of description,FIG.6only illustrates three optical sub-layers. The optical layer200comprises a first optical sub-layer201, a second optical sub-layer202, and a third optical sub-layer203. A refractive index of the first optical sub-layer201is greater than a refractive index of the second optical sub-layer202, and a refractive index of the third optical sub-layer203is greater than the refractive index of the second optical sub-layer202. The first optical sub-layer201and the second optical sub-layer202constitute the first optical structures200a, and the third optical sub-layer203covers the first optical structures200a.

Each of the first optical structures200acomprises two optical sub-layers, wherein the second optical sub-layer202covers the first optical sub-layer201. For convenience of production, when forming the first optical sub-layer201and the second optical sub-layer202, similar types of masks with different apertures may be used to pattern the first optical sub-layer201and the second optical sub-layer202to form the first optical sub-layer201and the second optical sub-layer202with different sizes but a same shape, which is not limited herein.

It is understandable that a side of each of the optical sub-layers in the first optical structures200aclose to the cathode suppression layer1035is a bottom, and a side of each of the optical sub-layers in the first optical structures200aaway from the cathode suppression layer1035is a top. A boundary of a bottom of the innermost optical sub-layer (such as the first optical sub-layer201) in each of the first optical structures200acorresponds to a boundary of one corresponding cathode suppression layer1035(that is, one corresponding light-transmitting area111). A boundary of a top of the outermost optical sub-layer (such as the second optical sub-layer202) in each of the first optical structures200ais correspondingly located between a boundary of one adjacent cathode suppression layer1035and a boundary of one adjacent pixel opening1001.

A structure of the display substrate in the display panel of this embodiment is same as a structure of the display substrate100in the display panel of the first embodiment, and a structure of a second display area of the display panel of this embodiment is same as a structure of the second display area12of the display panel of the first embodiment, which will not be described in detail herein.

In this embodiment, a side surface of each of the optical sub-layers in the first optical structures200amay be formed as a total reflective surface. In this way, when external light enters the first optical structures200a, the external light directed to the side surface of each of the optical sub-layers is totally reflected on an inner surface of the side surface of each of the optical sub-layers, thereby changing a path of the external light. Therefore, the external light originally directed outside light-transmitting areas111enters the light-transmitting areas111after being totally reflected, thereby increasing the amount of the light incident in the light-transmitting areas111. Accordingly, compared with the first embodiment, this embodiment can further increase a light transmittance of a first display area11.

Third Embodiment

Please refer toFIG.3,FIG.6,FIG.7, andFIG.8, a structure of a display panel of this embodiment is similar to the structure of the display panel of the first/second embodiment. A structure of a display substrate100in the display panel of this embodiment is same as a structure of the display substrate100in the display panel of the first embodiment, and a structure of a second display area12of the display panel of this embodiment is same as a structure of the second display area12of the display panel of the first embodiment, which will not be described in detail herein. This embodiment differs from the first/second embodiment in that in a first display area11, an optical layer200further comprises a plurality of second optical structures200bcorresponding to pixel openings1001. The second optical structures200bare disposed in a same layer as a first optical structures200a. Each of the second optical structures200bcomprises a first surface close to a cathode layer1034, a second surface opposite to the first surface, and a side surface200b′. An included angle between the side surface200b′ and the first surface of each of the second optical structures200bis a second included angle α2. The second included angle α2is 0° to 90°.

As shown inFIG.7, an orthographic projection of the second optical structures200bon the display substrate100overlaps with first cathode portions1034a. A cross-sectional shape of each of the second optical structures200bis same as or similar to a cross-sectional shape of each of the first optical structures200a. In a direction perpendicular to the display substrate100, a cross-sectional width of a side of each of the second optical structures200baway from the display substrate100is greater than or equal to a cross-sectional width of a side of each of the second optical structures200bclose to the display substrate100.

In an embodiment, sides of the second optical structures200bclose to a thin film encapsulation layer104are bottoms, and sides of the second optical structures200baway from the thin film encapsulation layer104are tops. A boundary of the bottom of each of the second optical structures200bcorresponds to a boundary of one corresponding pixel opening1001. A boundary of the top of each of the second optical structures200bis located between a boundary of one adjacent pixel opening1001and a boundary of one adjacent light-transmitting area111. Furthermore, the second optical structures200bare disposed alternately with the first optical structures200a.

As shown inFIG.2andFIG.3, in the second display area12of the display panel, each of touch electrodes304and touch electrode connecting wires305of a touch layer300is generally disposed between two adjacent pixel openings1001. Furthermore, the touch electrodes304and the touch electrode connecting wires305are made of a reflective and conductive metal. Therefore, a light emitted by organic light-emitting layers1033and directed between two adjacent pixel openings1001is reflected on surfaces of the touch electrodes304and the touch electrode connecting wires305(please refer to a light path shown inFIG.3). That is, a light emitted from second sub-pixels in the second display area12at a large viewing angle is blocked by the touch electrodes304and the touch electrode connecting wires305. However, in the first display area11, the touch electrodes304and the touch electrode connecting wires305are not disposed between two adjacent pixel openings1001. Therefore, a light emitted from first sub-pixels in the first display area11and directed between two adjacent pixel openings1001is not blocked. This results in a brightness difference between the first display area11and the second display area12.

In view of this technical problem, in this embodiment, the second optical structures200bare disposed at positions of the first display area11corresponding to the pixel openings1001. As shown inFIG.7andFIG.8, because a refractive index of the second optical structures200b(i.e. a first optical sub-layer201) is greater than a refractive index of a second optical sub-layer202, an interface (that is, the side surface200a′) between each of the second optical structures200band the second optical sub-layer202is a total reflective surface. When the light emitted by the organic light-emitting layers1033enters the second optical structures200b, the light directed to the side surfaces200b′ is totally reflected on inner surfaces of the side surfaces200b′, thereby changing a path of the light. In this way, the light originally emitted at the large viewing angle shifts to a normal viewing angle direction after being totally reflected, thereby increasing an amount of light emitted in a normal direction in the first sub-pixels and improving the brightness difference between the first display area11and the second display area12.

In an embodiment, when the second included angle α2between the side surface200b′ of each of the second optical structures200band a plane of the display substrate100is 90°, in the direction perpendicular to the display substrate100, the cross-sectional width of the side of each of the second optical structures200baway from the display substrate100is equal to the cross-sectional width of the side of each of the second optical structures200bclose to the display substrate100. Similar toFIG.5in the first embodiment, when the light emitted from the first sub-pixels enters the second optical structures200b, the light directed to the side surfaces200b′ is totally reflected on the inner surfaces of the side surfaces200b′, thereby changing the path of the light. In this way, the light originally emitted at the large viewing angle shifts to the normal viewing angle direction after being totally reflected, thereby increasing the amount of the light emitted in the normal direction in the first sub-pixels and improving the brightness difference between the first display area11and the second display area12.

As shown inFIG.8, theoretically, a minimum value of the second included angle α2is limited by a width and height of the pixel openings1001formed from a pixel defining layer1031. The width of the pixel openings1001is L, and the height of the pixel openings1001is H. The light emitted by the organic light-emitting layers1033disposed in the pixel openings1001has a certain viewing angle range after exiting the pixel openings1001. Lights a1 and a2 are lights with a maximum angle emitted by the organic light emitting layers1033from an edge of the pixel defining layer1031. It is understandable that when the second included angle α2is greater than a threshold angle α between the lights (such as the lights a1 or a2) with the maximum angle and the plane of the display substrate100, the light emitted by the organic light-emitting layers1033irradiates the side surfaces200b′ of the second optical structures200b.

The threshold angle α is arctan(H/L)*180°/π.

In an embodiment, the second included angle α2is greater than the threshold angle α, and less than or equal to 90°.

In an embodiment, in order to simplify a manufacturing process, the first included angle α1and the second included angle α2are same. That is, a shape and size of the first optical structures200aand a shape and size of the second optical structures200bare same.

In an embodiment, in order to maximize utilization of the second optical structures200b, a boundary of a bottom of each of the second optical structures200bclose to the cathode layer1034is located between a boundary of one corresponding pixel opening1001and a boundary beyond the boundary of the corresponding pixel opening1001by a predetermined distance d. When the boundary of the bottom of each of the second optical structures200bis located at an intersection (point A or point A′) of the light (such as lights a1 or a2) with the maximum angle and the optical layer200, the light with the maximum angle just irradiates a bottom of the side surface200b′ of one corresponding second optical structure200b, and the light emitted from one corresponding organic light-emitting layer1033just irradiates the entire side surfaces200b′.

The predetermined distance d is a vertical distance h from the pixel defining layer to the optical layer divided by a tangent value of the threshold angle α.

In an embodiment, the side surface200b′ of each of the second optical structure200bis an inclined surface or a curved surface.

Furthermore, when the side surface200b′ of each of the second optical structure200bis a curved surface, a radius of curvature of the curved surface is 1.5 μm to 5 μm.

InFIG.7, the first optical structures200aand the second optical structures200bhave a single-layer structure of an optical sub-layer. It is understandable that in other embodiments, the first optical structures200aand the second optical structures200bmay comprise at least two optical sub-layers with different refractive indices, and refractive indices of the optical sub-layers of the optical layer200decrease sequentially from a side close to the display substrate100to a side away from the display substrate100. For example, the first optical structures200aand the second optical structures200bcomprise at least two optical sub-layers, one optical sub-layer on the side away from the display substrate100covers one optical sub-layer on the side close to the display substrate100, and the at least two optical sub-layers in the first optical structures200aand the second optical structures200bhave a same cross-sectional shape in the direction perpendicular to the display substrate100. For details, please refer to a design of the first optical structures200ain the second embodiment andFIG.6, which will not be described in detail herein. Adopting such a design can further increase a light transmittance of the first display area and the amount of the light emitted in the normal direction in the first sub-pixels.

Compared with the first and second embodiments, in this embodiment, the second optical structures that can increase the amount of the light emitted in the normal direction are disposed above the pixel openings. Therefore, while increasing the light transmittance of the first display area, this embodiment can further increase the amount of the light emitted in the normal direction in the first sub-pixels in the first display area, thereby improving the brightness difference between the first display area and the second display area.

Fourth Embodiment

Please refer toFIG.3andFIG.9, a structure of a display panel of this embodiment is similar to the structure of the display panel of the first embodiment. A structure of a display substrate100in the display panel of this embodiment is same as the structure of the display substrate100in the display panel of the first embodiment, and a structure of a second display area12of the display panel of this embodiment is same as the structure of the second display area12of the display panel of the first embodiment, which will not be described in detail herein. This embodiment differs from the first/second embodiment in that an optical layer200comprises a first optical sub-layer201and a second optical sub-layer202, the second optical sub-layer202is disposed on a side of the first optical sub-layer201away from a base substrate101, and a refractive index of the first optical sub-layer201is less than a refractive index of the second optical sub-layer202.

Exemplarily, the refractive index of the first optical sub-layer201is 1-1.4, for example, it may be 1, 1.1, 1.2, 1.3, or 1.4. The refractive index of the second optical sub-layer202is 1.5-2, for example, it may be 1.5, 1.7, 1.8, or 2.

The first optical sub-layer201forms a plurality of first optical structures200a. A pixel defining layer1031of the display substrate100comprises a plurality of pixel openings1001spaced apart from each other and a plurality of supporting portions1031aeach disposed between two adjacent pixel openings1001. The first optical structures200aare correspondingly disposed on the supporting portions1031aeach disposed between two adjacent pixel openings1001. A surface of the display substrate100facing the first optical structures200ais provided with a plurality of cathode suppression layers1035. The cathode suppression layers1035are located on the supporting portions1031aeach disposed between two adjacent pixel openings1001. A light-transmitting area111is provided between every two adjacent pixel openings1001. Each of the cathode suppression layers1035is disposed corresponding to one light-transmitting area111.

Furthermore, each of the first optical structures200ais located between one pixel opening1001and one cathode suppression layer1035. In addition, in a direction perpendicular to the display substrate100, a cross-sectional width w2 of a side of each of the first optical structures200aaway from the display substrate100is less than or equal to a cross-sectional width w1 of a side of each of the first optical structures200aclose to the display substrate100.

In an embodiment, an orthographic projection of the first optical structures200aon the display substrate100does not overlap with the cathode suppression layers1035.

In an embodiment, a boundary of each of the first optical structures200ais located between a boundary of one adjacent pixel opening1001and a boundary of one adjacent cathode suppression layer1035.

Furthermore, sides of the first optical structures200aclose to the cathode suppression layers1035are bottoms, and sides of the first optical structures200aaway from the cathode suppression layers1035are tops. A side of the bottom of each of the first optical structures200aclose to one adjacent pixel opening1001corresponds to a side of the adjacent pixel opening1001, and a side of the bottom of each of the first optical structures200aclose to one adjacent light-transmitting area111corresponds to a side of the adjacent cathode suppression layer1035.

A first included angle α1between a side surface200a′ of each of the first optical structures200aand a plane of the display substrate100is 0° to 90°. For example, the first included angle α1is 15°, 30°, 45°, 60°, 70°, 80°, or 90°.

In this embodiment, the first optical structures200ahave functions of increasing an amount of light incident in the light-transmitting areas111and increasing an amount of light emitted in a normal direction in first sub-pixels. Considering the above comprehensively, the first included angle α1is greater than a threshold angle and less than or equal to 90°.

In this embodiment, because the refractive index of the second optical sub-layer202is greater than a refractive index of the first optical structures200a(that is, the first optical sub-layer), an interface (that is, the side surface200a′) between each of the first optical structures200aand the second optical sub-layer202is a total reflective surface. When external light is directed to a portion of the side surface200a′ of each of the first optical structures200aclose to one adjacent light-transmitting area111, the external light is totally reflected on an outer surface of the side surface200a′, thereby changing a path of the external light. Therefore, the external light originally directed outside the light-transmitting areas111enters the light-transmitting areas111after being totally reflected, thereby increasing an amount of light incident in the light-transmitting areas111and increasing the light transmittance of the first display area11.

Furthermore, when a light emitted by organic light-emitting layers1033is directed to a portion of the side surface200a′ of each of the second optical structures200bclose to one adjacent pixel openings1001, the light is totally reflected on an outer surface of the side surface200b′, thereby changing a path of the light. In this way, the light originally emitted at the large viewing angle shifts to a normal viewing angle direction after being totally reflected, thereby increasing an amount of light emitted in a normal direction in the first sub-pixels and improving the brightness difference between the first display area11and the second display area12.

Accordingly, compared with the first embodiment, this embodiment can increase the light transmittance of the first display area, and increase the amount of the light emitted in the normal direction in the first sub-pixels in the first display area, thereby improving the brightness difference between the first display area and the second display area.

Fifth Embodiment

Please refer toFIG.3andFIG.10, a structure of a display panel of this embodiment is similar to the structure of the display panel of the fourth embodiment. This embodiment differs from the fourth embodiment in that an optical layer200of the display panel of this embodiment comprises a plurality of optical sub-layers with different refractive indices, and at least two of the optical sub-layers form first optical structures200a. Refractive indices of the optical sub-layers increase sequentially from a side close to a display substrate100to a side away from the display substrate100. One optical sub-layer on a side away from the display substrate100covers one optical sub-layer on a side close to the display substrate100, and the at least two optical sub-layers in the first optical structures200ahave a same cross-sectional shape in a direction perpendicular to the display substrate100.

Please refer toFIG.10for details. For convenience of description,FIG.10only illustrates three optical sub-layers. The optical layer200comprises a first optical sub-layer201, a second optical sub-layer202, and a third optical sub-layer203. A refractive index of the first optical sub-layer201is less than a refractive index of the second optical sub-layer202, and the refractive index of the second optical sub-layer202is less than a refractive index of the third optical sub-layer203. The first optical sub-layer201and the second optical sub-layer202constitute the first optical structures200a, and the third optical sub-layer203covers the first optical structures200a.

A structure of the display substrate100in the display panel of this embodiment is same as a structure of the display substrate100in the display panel of the first embodiment, and a structure of a second display area12of the display panel of this embodiment is same as the structure of the second display area12of the display panel of the first embodiment, which will not be described in detail herein.

In this embodiment, a side surface of each of the optical sub-layers in the first optical structures200amay be formed as a total reflective surface. Therefore, on the basis of the fourth embodiment, this embodiment can further increase the light transmittance of the first display area and the amount of the light emitted in the normal direction in the first sub-pixels.

The present invention is described in detail above. The present disclosure uses specific examples to describe principles and embodiments of the present invention. The above description of the embodiments is only for helping to understand solutions of the present invention and its core ideas. Furthermore, those skilled in the art may make modifications to the specific embodiments and applications according to ideas of the present invention. In conclusion, the present specification should not be construed as a limitation to the present invention.