Display panel, preparation method thereof and display device

Abstract

The invention provides a display panel, a preparation method thereof and a display device. The display panel comprises a driving backboard, a plurality of sub-pixels emitting light of different colors are formed on one side of the driving backboard, each sub-pixel comprises a pixel defining layer, the pixel defining layer is located on one side of the driving backboard and provided with a pixel opening, and a light-emitting function layer of the sub-pixels is formed in the pixel opening; the display panel further comprises a plurality of light absorption structures, the light absorption structures correspond to at least part of the sub-pixels, the light absorption structures are located on the pixel defining layer and surround the corresponding sub-pixels in the circumferential direction, and the minimum light absorption wavelength of each light absorption structure is smaller than or equal to the minimum light emitting wavelength of the corresponding sub-pixel. And the maximum light absorption wavelength of the light absorption structure is greater than or equal to the maximum light emitting wavelength of the sub-pixel corresponding to the light absorption structure.

Description

Technical Field

[0001] The present disclosure relates to the field of display technology, and in particular, to a display panel and a method for manufacturing the same, and a display device. Background Art

[0002] Active matrix organic electroluminescent device (AMOLED) is a new generation of new display technology with great application prospects. OLED display devices are self-luminous and have the advantages of low driving voltage, high luminous efficiency, short response time, high clarity and contrast, nearly 180° viewing angle, wide operating temperature range and transparent preparation, which can realize flexible display and large-area full-color display. AMOLED is composed of three primary colors RGB to form array sub-pixels, and different chromaticities are displayed by controlling the luminous brightness of RGB sub-pixels. Usually, the terminal device installs an ambient light sensor on the back of the AMOLED panel to sense the brightness of the user's usage scene, so as to automatically adjust the display brightness of the terminal device, protect the user's eyesight and reduce its own power consumption. In the related technology, there is a problem of low sensing accuracy.

[0003] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present disclosure, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Summary of the invention

[0004] The purpose of the present disclosure is to overcome the above-mentioned deficiencies of the prior art and to provide a display panel and a method for manufacturing the same, and a display device.

[0005] According to one aspect of the present disclosure, a display panel is provided, comprising: a driving backplane, a plurality of sub-pixels emitting light of different colors being formed on one side of the driving backplane; a pixel defining layer located on one side of the driving backplane, the pixel defining layer having a pixel opening, a light-emitting functional layer of the sub-pixel being formed in the pixel opening; and a plurality of light absorption structures arranged corresponding to at least some of the sub-pixels, the light absorption structures being located on the pixel defining layer and circumferentially arranged around the corresponding pixel openings, the minimum light absorption wavelength of the light absorption structures being less than or equal to the minimum light emission wavelength of the sub-pixels corresponding thereto, and the maximum light absorption wavelength of the light absorption structures being greater than or equal to the maximum light emission wavelength of the sub-pixels corresponding thereto.

[0006] In an exemplary embodiment of the present disclosure, the display panel has a photosensitive area, and the photosensitive area has a photoelectric sensor; wherein the light absorption structure is arranged corresponding to at least part of the sub-pixels of the photosensitive area.

[0007] In an exemplary embodiment of the present disclosure, the photosensitive area includes an R sub-pixel, a G sub-pixel and a B sub-pixel, and the light absorption structure includes a first light absorption structure; the first light absorption structure is arranged corresponding to at least part of the G sub-pixels, the minimum light absorption wavelength of the first light absorption structure is less than or equal to the minimum light emission wavelength of the G sub-pixels, and the maximum light absorption wavelength of the first light absorption structure is greater than or equal to the maximum light emission wavelength of the G sub-pixels.

[0008] In an exemplary embodiment of the present disclosure, the minimum absorption wavelength of the first light absorption structure is also less than or equal to the minimum emission wavelength of the B sub-pixel, and the maximum absorption wavelength of the first light absorption structure is also greater than or equal to the maximum emission wavelength of the B sub-pixel.

[0009] In an exemplary embodiment of the present disclosure, the photosensitive area includes R sub-pixels, G sub-pixels and B sub-pixels, and the light absorption structure includes two light absorption structures among a first light absorption structure, a second light absorption structure and a third light absorption structure; wherein the first light absorption structure is arranged corresponding to at least part of the G sub-pixels, the second light absorption structure is arranged corresponding to at least part of the R sub-pixels, and the third light absorption structure is arranged corresponding to at least part of the B sub-pixels.

[0010] In an exemplary embodiment of the present disclosure, the photosensitive area includes R sub-pixels, G sub-pixels and B sub-pixels, and the light absorption structure includes a first light absorption structure, a second light absorption structure and a third light absorption structure; wherein the first light absorption structure is arranged corresponding to at least part of the G sub-pixels, the second light absorption structure is arranged corresponding to at least part of the R sub-pixels, and the third light absorption structure is arranged corresponding to at least part of the B sub-pixels.

[0011] In an exemplary embodiment of the present disclosure, the minimum absorption wavelengths of the first light absorption structure, the second light absorption structure and the third light absorption structure are the same, and the maximum absorption wavelengths are also the same, and the minimum absorption wavelength of any light absorption structure is greater than or equal to the minimum light emission wavelength of the B sub-pixel, and the maximum absorption wavelength is also greater than or equal to the maximum light emission wavelength of the B sub-pixel.

[0012] In an exemplary embodiment of the present disclosure, the material of the light absorption structure includes a compound represented by the following structural formula (1):

[0013]

[0014] Alternatively, the material of the light absorption structure is a black material.

[0015] In an exemplary embodiment of the present disclosure, the display panel also includes: a first electrode layer, including a plurality of first electrodes distributed in an array, the pixel defining layer having the pixel opening at the first electrode, and the light-emitting functional layer is formed on a side of the first electrode facing away from the driving backplane; wherein the orthographic projection of the light absorption structure on the driving backplane at least partially overlaps with the orthographic projection of the first electrode on the driving backplane.

[0016] In an exemplary embodiment of the present disclosure, the display panel also includes: a first electrode layer, including a plurality of first electrodes distributed in an array, the pixel defining layer having the pixel opening at the first electrode, and the light-emitting functional layer is formed on a side of the first electrode facing away from the driving backplane; wherein the orthographic projection of the light absorption structure on the driving backplane does not overlap with the orthographic projection of the first electrode on the driving backplane.

[0017] In an exemplary embodiment of the present disclosure, the display panel also includes: a first electrode layer, including a plurality of first electrodes distributed in an array, the pixel defining layer having the pixel opening at the first electrode, and the light-emitting functional layer is formed on a side of the first electrode away from the driving backplane; wherein the light absorption structure contacts the side wall of the corresponding first electrode.

[0018] In an exemplary embodiment of the present disclosure, the display panel also includes: a first electrode layer, including a plurality of first electrodes distributed in an array, the pixel defining layer having the pixel opening at the first electrode, and the light-emitting functional layer being formed on a side of the first electrode facing away from the driving backplane; wherein the minimum width of the light absorption structure on the orthographic projection of the driving backplane is a first width, and there is a gap between the light absorption structure and the corresponding first electrode, and the gap width is less than or equal to the first width.

[0019] In an exemplary embodiment of the present disclosure, a ratio of the gap width to the first width is greater than 0 and less than or equal to 1.

[0020] In an exemplary embodiment of the present disclosure, the light absorption structure penetrates the pixel defining layer in a thickness direction of the driving backplane.

[0021] In an exemplary embodiment of the present disclosure, the light absorption structure has a bottom surface and a top surface arranged opposite to each other in the thickness direction of the driving backplane, the bottom surface is located on the side of the top surface close to the driving backplane, and the pixel defining layer covers the top surface of the light absorption structure.

[0022] In an exemplary embodiment of the present disclosure, the display panel also includes: a second electrode layer, located on the side of the pixel defining layer away from the driving backplane, and at least one side of at least a portion of the pixel defining layer contacts the second electrode layer and the other side contacts the driving backplane; wherein, in the thickness direction of the driving backplane, the light absorption structure has a first thickness between the top and bottom surfaces, the pixel defining layer has a second thickness at a position contacting the second electrode layer, and the ratio of the first thickness to the second thickness is greater than or equal to 0.6.

[0023] In an exemplary embodiment of the present disclosure, the light absorbing structure includes a first structural layer and a second structural layer parallel to the driving backplane, and the first structural layer is located at any position of the second structural layer on a side away from the driving backplane; wherein the orthographic projection of the first structural layer on the driving backplane is located within the orthographic projection of the second structure on the driving backplane, or the orthographic projection of the first structural layer on the driving backplane overlaps with the orthographic projection of the second structure on the driving backplane.

[0024] In an exemplary embodiment of the present disclosure, the light absorption structure includes a first structural layer and a second structural layer parallel to the driving backplane, and the first structural layer is located at any position of the second structural layer on a side away from the driving backplane; wherein the orthographic projection of the second structural layer on the driving backplane is located within the orthographic projection of the first structural layer on the driving backplane.

[0025] In an exemplary embodiment of the present disclosure, the orthographic projection of the light absorption structure on the driving back plate is a circular ring or a regular polygonal ring.

[0026] In an exemplary embodiment of the present disclosure, the light absorption structure has a minimum width of a first width in an orthographic projection on the driving backplane, and the first width is greater than or equal to 0.5 μm and less than or equal to 2 μm.

[0027] In an exemplary embodiment of the present disclosure, a slope angle formed by a side wall and a bottom surface of the light absorption structure is greater than or equal to 20° and less than or equal to 90°.

[0028] In an exemplary embodiment of the present disclosure, a slope angle formed by a side wall and a bottom surface of the light absorption structure is greater than 90° and less than or equal to 160°.

[0029] In an exemplary embodiment of the present disclosure, the sub-pixel includes at least a first light-emitting unit and a second light-emitting unit stacked on one side of the driving backplane, and the first light-emitting unit is connected in series through a charge generating layer; the sub-pixel has a light-emitting phase and a non-light-emitting phase, and the photoelectric sensor located in the photosensitive area has a sensing phase and a non-sensing phase, wherein the sensing phase of the photoelectric sensor does not overlap with the light-emitting phase of the sub-pixel.

[0030] According to the second aspect of the present disclosure, a method for preparing a display panel is also provided, which is used to prepare the display panel described in any embodiment of the present disclosure, and the method includes: providing a driving backplane; forming a plurality of light absorption structures in at least a partial area on one side of the driving backplane, wherein the minimum light absorption wavelength of the light absorption structure is less than or equal to the minimum light emission wavelength of the sub-pixel corresponding thereto, and the maximum light absorption wavelength of the light absorption structure is greater than or equal to the maximum light emission wavelength of the sub-pixel corresponding thereto; forming a pixel defining layer on one side of the driving backplane; forming pixel openings in the pixel defining layer using a composition process, wherein the light absorption structures are circumferentially arranged around the corresponding pixel openings; and forming a light-emitting functional layer in the pixel openings using a vapor deposition process.

[0031] According to a third aspect of the present disclosure, a display device is also provided, comprising the display panel described in any embodiment of the present disclosure.

[0032] The display panel provided by the present disclosure has a light absorption structure disposed on the pixel defining layer, the minimum light absorption wavelength of the light absorption structure is less than or equal to the minimum light emission wavelength of the corresponding sub-pixel, and the maximum light absorption wavelength of the light absorption structure is greater than or equal to the maximum light emission wavelength of the corresponding sub-pixel, so that the light absorption structure has an absorption effect on the light emitted by the sub-pixel corresponding thereto. The light absorption structure is disposed circumferentially around the pixel opening, so that the light absorption structure can absorb the lateral light leakage generated by the corresponding sub-pixel, and prevent the lateral light leakage from being transmitted to the photoelectric sensor for detecting ambient light in the display panel, thereby reducing the non-ambient light interference on the photoelectric sensor, and improving the sensing accuracy of the photoelectric sensor for ambient light.

[0033] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The accompanying drawings herein are incorporated into the specification and constitute a part of the specification, illustrate embodiments consistent with the present disclosure, and together with the specification are used to explain the principles of the present disclosure. Obviously, the accompanying drawings described below are only some embodiments of the present disclosure, and for ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without creative work.

[0035] Figure 1 is a schematic structural diagram of a display panel according to an embodiment of the present disclosure;

[0036] Figure 2 for Figure 1 A partial magnified image of the middle photosensitive area;

[0037] Figure 3 for Figure 2 A cross-sectional view along the dotted line AA;

[0038] Figure 4 A schematic diagram of the lateral light leakage of a sub-pixel being sensed by a photosensor in the related art;

[0039] Figure 5 is a schematic diagram of a stack of sub-pixels according to an embodiment of the present disclosure;

[0040] Figure 6 is a circuit diagram of a pixel driving circuit according to an embodiment of the present disclosure;

[0041] Figure 7 for Figure 6 A timing diagram of each node in a driving method of a pixel driving circuit;

[0042] Figure 8 is a brightness attenuation curve diagram of a sub-pixel in an EM-off stage according to an embodiment of the present disclosure;

[0043] Figure 9-Figure 20 is a schematic diagram of the distribution of the light-absorbing structure in the photosensitive area according to one embodiment of the present disclosure;

[0044] Fig.21 is an absorption spectrum curve of a compound according to one embodiment of the present disclosure;

[0045] Fig. 22 is a cross-sectional view of a light absorption structure and a sub-pixel according to an embodiment of the present disclosure;

[0046] Fig.23 is a cross-sectional view of a light absorption structure and a sub-pixel according to another embodiment of the present disclosure;

[0047] Fig.24 A cross-sectional view of a light absorption structure and a sub-pixel according to another embodiment of the present disclosure

[0048] Fig.25 is a top view of a light absorption structure and a sub-pixel according to another embodiment of the present disclosure;

[0049] Fig.26 for Fig.25 A cross-sectional view along the dotted line AA;

[0050] Figure 27-Figure 29 for Fig.25 A partial magnified image of a light-absorbing structure;

[0051] Fig.30 is a cross-sectional view of a light absorption structure and a sub-pixel according to an embodiment of the present disclosure;

[0052] Fig.31 for Fig.30 A partial magnified image of the light-absorbing structure;

[0053] Fig.32 is a cross-sectional view of a light absorption structure and a sub-pixel according to another embodiment of the present disclosure;

[0054] Fig.33 for Fig.32 A partial magnified image of the light-absorbing structure;

[0055] Fig.34 is a cross-sectional view of a light absorption structure and a sub-pixel according to another embodiment of the present disclosure;

[0056] Fig.35 for Fig.34 A partial magnified image of the light-absorbing structure;

[0057] Figure 36-Figure 39 The present invention is a flow chart of a method for preparing a display panel according to an embodiment of the present invention. DETAILED DESCRIPTION

[0058] Example embodiments will now be described more fully with reference to the accompanying drawings. However, the example embodiments can be implemented in a variety of forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that the present disclosure will be comprehensive and complete and fully convey the concepts of the example embodiments to those skilled in the art. The same reference numerals in the figures represent the same or similar structures, and thus their detailed description will be omitted. In addition, the drawings are only schematic illustrations of the present disclosure and are not necessarily drawn to scale.

[0059] In the related technology, terminal devices usually install ambient light sensing photoelectric sensors on the back of the AMOLED panel to identify the brightness of the user's usage scene, so as to dynamically adjust the display brightness of the terminal device, protect the user's eyesight while also reducing its own power consumption.

[0060] The light released by the OLED during the discharge process of the device after power failure is refracted and reflected by the anode, cathode, and organic and inorganic film layers, passes through the blank area of ​​the driving backplane wiring, and is received by the ambient light sensing photoelectric sensor under the backplane, thereby affecting the sensitivity of the ambient light sensing photoelectric sensor.

[0061] Figure 1 is a schematic structural diagram of a display panel according to an embodiment of the present disclosure, Figure 2 for Figure 1 A partial enlarged view of the middle photosensitive area. Figure 3 for Figure 2 The cross-sectional view along the dotted line AA is as follows: Figure 2 and Figure 3As shown, the display panel may include a driving backplane 110, a pixel defining layer PDL and a plurality of light absorption structures 120, wherein a plurality of sub-pixels emitting light of different colors are formed on one side of the driving backplane 110, the pixel defining layer PDL is located on one side of the driving backplane 110, the pixel defining layer PDL has a pixel opening, and a light-emitting functional layer of the sub-pixel is formed in the pixel opening; the light absorption structure 120 is arranged corresponding to at least part of the sub-pixels, the light absorption structure 120 is located in the pixel defining layer PDL and is circumferentially arranged around the corresponding pixel opening, the minimum light absorption wavelength of the light absorption structure 120 is less than or equal to the minimum light emission wavelength of the sub-pixel corresponding thereto, and the maximum light absorption wavelength of the light absorption structure 120 is greater than or equal to the maximum light emission wavelength of the sub-pixel corresponding thereto.

[0062] The display panel provided by the present disclosure has a light absorption structure 120 disposed in the pixel definition layer PDL, the minimum light absorption wavelength of the light absorption structure 120 is less than or equal to the minimum light emission wavelength of the corresponding sub-pixel, and the maximum light absorption wavelength of the light absorption structure 120 is greater than or equal to the maximum light emission wavelength of the corresponding sub-pixel, so that the light absorption structure 120 has an absorption effect on the light emitted by the sub-pixel corresponding thereto. The light absorption structure 120 is disposed circumferentially around the pixel opening, so that the light absorption structure 120 can absorb the lateral light leakage generated by the corresponding sub-pixel, and prevent the lateral light leakage from transmitting to the photoelectric sensor 101 in the display panel that detects ambient light, thereby reducing the non-ambient light interference on the photoelectric sensor 101 and improving the sensing accuracy of the photoelectric sensor 101 for ambient light.

[0063] The light absorption structure 120 of the present disclosure is arranged correspondingly to at least some of the sub-pixels, which can be understood as at least some of the sub-pixels in the display panel are provided with the light absorption structure 120, for example, the light absorption structure 120 is arranged one-to-one with some of the sub-pixels. Figure 1 As shown, the display panel may have a photosensitive area 200, which may be located in the display area. A photoelectric sensor 101 for identifying the brightness of the environment may be provided in the photosensitive area 200, and the display brightness of the display device may be automatically adjusted based on the sensing signal of the photoelectric sensor 101. Therefore, the multiple light absorption structures 120 of the present disclosure are provided corresponding to at least some of the sub-pixels, and specifically, the multiple light absorption structures 120 may be provided corresponding to at least some of the sub-pixels in the photosensitive area 200. Figure 1 As shown, the photosensitive area 200 of the present disclosure is located in the display area. In addition to being provided with the photoelectric sensor 101 and the light absorption structure 120, the photosensitive area 200 may have all the features of other areas of the display area, which will not be repeated here.

[0064] like Figure 2As shown, the light absorption structure 120 is arranged around the corresponding pixel opening, that is, the light absorption structure 120 forms an area around the pixel opening, and the corresponding pixel opening is located in the area. For example, the orthographic projection of the light absorption structure 120 on the driving backplane 110 is a ring, and the orthographic projection of the pixel opening on the driving backplane 110 is located within the orthographic projection of the ring.

[0065] like Figure 3 As shown, the light absorption structure 120 is arranged in the circumferential direction of the corresponding pixel opening, so that the lateral light leakage generated by the sub-pixel in the pixel opening (including the light directly generated by the sub-pixel and the light reflected by other film layers) will be transmitted to the light absorption structure 120, that is, the light absorption structure 120 is equivalent to being located on the propagation path of the lateral light leakage of the sub-pixel. In this way, the lateral light leakage generated by the sub-pixel will be absorbed by the light absorption structure 120 located on the light transmission path, thereby preventing the lateral light leakage generated by the sub-pixel from being transmitted to the photoelectric sensor 101, so that the photoelectric sensor 101 only senses the ambient light during the sensing stage, thereby eliminating the influence of the lateral light leakage of the sub-pixel on the ambient light detection result, and improving the sensing accuracy of the ambient light. In contrast, Figure 4 Schematic diagram of the lateral light leakage of a sub-pixel being sensed by a photoelectric sensor in the related art, such as Figure 4 As shown, after being reflected by the second electrode layer (which may be a cathode layer), light a and light b are transmitted through the organic layer below to the ambient light sensor below the driving backplane, while light c is refracted by the pixel definition layer and the organic layer and directly transmitted to the photosensor 101 below, thus making the detection result of the photosensor 101 inaccurate. Figure 3 It can be seen that after setting the light absorption structure, light a, light b and light c originating from the lateral light leakage of the sub-pixel will all be absorbed by the circumferentially arranged light absorption structure 120, so that the detection result of the photosensor 101 is no longer affected by the lateral light leakage of the sub-pixel. Therefore, the present disclosure can improve the sensing accuracy of ambient light by setting the light absorption structure 120.

[0066] The light absorption structure 120 of the present disclosure includes a light absorption material to absorb light of a specific wavelength through the light absorption material. The minimum absorption wavelength and the maximum absorption wavelength are the limit absorption wavelengths of the light absorption structure 120, and the minimum absorption wavelength is the minimum wavelength of light that the light absorption structure 120 can absorb, that is, light less than the minimum absorption wavelength cannot be absorbed by the light absorption structure 120. The maximum absorption wavelength is the maximum wavelength that the light absorption structure 120 can absorb, that is, light greater than the maximum absorption wavelength cannot be absorbed by the light absorption structure 120. In other words, light with a wavelength between the minimum absorption wavelength and the maximum absorption wavelength will be absorbed by the light absorption structure 120. In the present disclosure, the minimum absorption wavelength of the light absorption structure 120 is greater than or equal to the minimum emission wavelength of the corresponding sub-pixel, and the maximum absorption wavelength of the light absorption structure 120 is greater than or equal to the maximum emission wavelength of the corresponding sub-pixel, that is, the light absorption structure 120 can absorb the full-band light emitted by the corresponding sub-pixel. The display panel block disclosed in the present invention can be an OLED display panel, which can have an organic electroluminescent layer. The minimum emission wavelength and the maximum emission wavelength of the sub-pixel can be obtained by measuring the luminous intensity of light of different wavelengths emitted by the organic electroluminescent layer material forming the sub-pixel, wherein the minimum emission wavelength is the minimum wavelength of the band in which the light emitted by the organic electroluminescent layer material is located, and the maximum emission wavelength is the maximum wavelength of the band in which the light emitted by the organic electroluminescent layer material is located.

[0067] The display panel of the present disclosure may include a pixel definition layer PDL, a first electrode layer, a light emitting function layer, and a second electrode layer in the display area. Figure 3 As shown, the pixel defining layer PDL and the first electrode layer are arranged on the same surface of the driving backplane 110, and the pixel defining layer PDL exposes each first electrode ANO. Specifically, the pixel defining layer PDL may be provided with a plurality of pixel openings exposing each first electrode ANO. The orthographic projection of any pixel opening on the substrate substrate may be located within the first electrode ANO exposed therefrom, that is, the pixel opening is not larger than the first electrode ANO exposed therefrom. For example: the boundary of the pixel opening is located on the inner side of the boundary of the first electrode ANO exposed therefrom, that is, the area of ​​the pixel opening is smaller than the area of ​​the first electrode ANO exposed therefrom. The shape of the pixel opening may be a polygon such as a rectangle, a pentagon, or a hexagon, but it is not necessarily a regular polygon. The shape of the pixel opening may also be other shapes such as an ellipse, which is not specifically limited here. The first electrode layer may be an anode layer, and the second electrode layer may be a cathode layer. The present disclosure is only exemplified by taking the first electrode layer as an anode layer and the second electrode layer as a cathode layer as an example. Of course, in other embodiments, the first electrode layer may also be a cathode layer, and the second electrode layer may also be an anode layer.

[0068] like Figure 3As shown, the light-emitting functional layer covers the pixel definition layer PDL and the first electrode ANO, and the area where the light-emitting functional layer and the first electrode ANO overlap is used to form a sub-pixel. The light-emitting functional layer is located in the pixel opening, and the light absorption structure is arranged circumferentially around the pixel opening, which is equivalent to the light absorption structure being arranged circumferentially around the sub-pixel.

[0069] The sub-pixel disclosed in the present invention may be a tandem OLED device, that is, a tandem OLED device including a plurality of light-emitting devices OLED connected in series. Compared with a single OLED device, a tandem OLED device has the characteristics of high efficiency and long life. Figure 5 FIG. 1 is a schematic diagram of a stack of sub-pixels according to an embodiment of the present disclosure, as shown in FIG. Figure 5 As shown, each sub-pixel includes a first electrode ANO, a second electrode CAT, and a plurality of sub-light-emitting layers between the first electrode ANO and the second electrode CAT (the figure only takes the sub-pixel including the first sub-light-emitting layer 10 and the second sub-light-emitting layer 20 as an example for illustrative explanation), and each light-emitting device of the same sub-pixel can share the same first electrode ANO and the same second electrode CAT, that is, the same sub-pixel can have only one first electrode ANO and one second electrode CAT.

[0070] For example, Figure 5 As shown, the light-emitting functional layer may include multiple sub-light-emitting layers connected in series in a direction away from the driving backplane 110, and at least one sub-light-emitting layer is connected in series with an adjacent sub-light-emitting layer through the charge generation layer CGL. When an electrical signal is applied to the first electrode ANO and the second electrode CAT, each sub-light-emitting layer can emit light, and different sub-light-emitting layers can be used to emit light of different colors.

[0071] Any sub-light-emitting layer may include a hole injection layer HIL, a hole transport layer HTL, an organic electroluminescent layer EML, an electron transport layer ETL and an electron injection layer EIL distributed along the thickness direction away from the driving backplane 110. The specific light-emitting principle is not described in detail here, wherein the number of the hole injection layer HIL, the hole transport layer HTL, the electron transport layer ETL and the electron injection layer EIL is not specifically limited here, and adjacent sub-light-emitting layers may share one or more of the hole injection layer HIL, the hole transport layer HTL, the electron transport layer ETL and the electron injection layer EIL. At the same time, a charge generation layer CGL may be provided between at least two adjacent sub-light-emitting layers, so that the two sub-light-emitting layers are connected in series to form a Tandem OLED device.

[0072] In addition, the display panel may further include a color filter layer (not shown in the figure), which may be arranged on the side of the second electrode CAT away from the driving backplane 110, and includes a plurality of filter parts, each first electrode ANO and each filter part are arranged one by one in a direction perpendicular to the driving backplane 110, that is, the positive projection of a filter part on the driving backplane 110 overlaps at least partially with a first electrode ANO. Each filter part includes at least three color filter parts, for example, it may include a filter part that transmits red light, a filter part that transmits green light, and a filter part that transmits blue light. After the light emitted by each light-emitting unit passes through the filter part, monochromatic light of different colors can be obtained, thereby realizing color display, wherein a filter part and its corresponding light-emitting unit can constitute a sub-pixel, and the color of light emitted by any sub-pixel is the color of the light transmitted by its filter part, and multiple sub-pixels can constitute a pixel, and the light-emitting colors of each sub-pixel of the same pixel are different. The color filter layer may also include a shading part that separates the filter part, the shading part is not light-transmissive, and blocks the area between the two light-emitting units.

[0073] The above-mentioned light-emitting functional layer structure is only for illustrative purposes and does not constitute a limitation on its film layer. It may include only two sub-light-emitting layers, or more, or only one sub-light-emitting layer, as long as it can cooperate with the color filter layer to achieve color display.

[0074] The driving backplane may include a plurality of transistors forming a pixel driving circuit, and the pixel driving circuit may be, for example, 7T1C, 8T1C, etc. Taking 7T1C as an example, Figure 6 FIG. 1 is a circuit diagram of a pixel driving circuit according to an embodiment of the present disclosure, as shown in FIG. Figure 6As shown, the pixel driving circuit may include: a first transistor T1, a second transistor T2, a driving transistor T3, a fourth transistor T4, a fifth transistor T5, a sixth transistor T6, a seventh transistor T7, and a capacitor C. Among them, the first electrode of the first transistor T1 is connected to the node N, the second electrode is connected to the first initial signal terminal Vinit1, and the gate is connected to the reset signal terminal Re1; the first electrode of the second transistor T2 is connected to the first electrode of the driving transistor T3, the second electrode is connected to the node N; the gate is connected to the gate driving signal terminal Gate; the gate of the driving transistor T3 is connected to the node N; the first electrode of the fourth transistor T4 is connected to the data signal terminal Da, the second electrode is connected to the second electrode of the driving transistor T3, and the gate is connected to the gate driving signal terminal Gate; the first electrode of the fifth transistor T5 is connected to the second electrode of the driving transistor T3, the second electrode is connected to the first power supply terminal VDD, and the gate is connected to the enable signal terminal EM; the first electrode of the sixth transistor T6 is connected to the first electrode of the driving transistor T3, and the gate is connected to the enable signal terminal EM; the first electrode of the seventh transistor T7 is connected to the second electrode of the sixth transistor T6, the second electrode is connected to the second initial signal terminal Vinit2, and the gate is connected to the reset signal terminal Re2. The capacitor C is connected between the gate of the driving transistor T3 and the first power supply terminal VDD. The pixel driving circuit can be connected to a light-emitting unit OLED (the light-emitting unit OLED can be, for example, the above-mentioned Tandem OLED) to drive the light-emitting unit OLED to emit light. The light-emitting unit OLED can be connected between the second electrode of the sixth transistor T6 and the second power supply terminal VSS. Among them, the transistors T1 to T7 can all be P-type transistors or N-type transistors, or some are P-type transistors and some are N-type transistors. For example, the first transistor T1 to the seventh transistor T7 are all P-type transistors or all are N-type transistors, or the first transistor T1 and the second transistor T2 are P-type transistors, and the third transistor T3 to the seventh transistor T7 are N-type transistors, etc.

[0075] It should be noted that the transistors used in each embodiment of the present disclosure can be thin film transistors or field effect transistors or other devices with the same characteristics. In this specification, the first electrode can be a drain electrode and the second electrode can be a source electrode, or the first electrode can be a source electrode and the second electrode can be a drain electrode.

[0076] Figure 7 for Figure 6A timing diagram of each node in a driving method of a pixel driving circuit. Wherein, Gate represents the timing of the gate driving signal terminal Gate, Re1 represents the timing of the reset signal terminal Re1, Re2 represents the timing of the reset signal terminal Re2, EM represents the timing of the enable signal terminal EM, and Da represents the timing of the data signal terminal Da. The driving method of the pixel driving circuit may include a reset stage t1, a compensation stage t2, and a light-emitting stage t3. In the reset stage t1: the reset signal terminal Re1 outputs a low-level signal, the first transistor T1 is turned on, and the first initial signal terminal Vinit1 inputs an initial signal to the node N. In the compensation stage t2: the reset signal terminal Re2 and the gate driving signal terminal Gate output low-level signals, the fourth transistor T4, the second transistor T2, and the seventh transistor T7 are turned on, and at the same time, the data signal terminal Da outputs a driving signal to write a voltage Vdata+Vth to the node N, wherein Vdata is the voltage of the driving signal, Vth is the threshold voltage of the driving transistor T3, and the second initial signal terminal Vinit2 inputs an initial signal to the second electrode of the sixth transistor T6. Light-emitting stage t3: the enable signal terminal EM outputs a low-level signal, the sixth transistor T6 and the fifth transistor T5 are turned on, and the light-emitting unit OLED emits light under the voltage Vdata+Vth stored in the capacitor C. According to the output current formula of the driving transistor I=(μWCox / 2L)(Vgs-Vth) 2 , where μ is carrier mobility; Cox is the gate capacitance per unit area, W is the width of the driving transistor channel, L is the length of the driving transistor channel, Vgs is the gate-source voltage difference of the driving transistor, and Vth is the threshold voltage of the driving transistor. The output current of the driving transistor in the pixel driving circuit of the present disclosure is I = (μWCox / 2L)(Vdata+Vth-Vdd-Vth) 2 The pixel driving circuit can avoid the influence of the threshold voltage of the driving transistor on its output current.

[0077] The dimming mode of the AMOLED display panel is mainly PWM (Pulse width modulation) dimming, and the display brightness of the display device can be adjusted by controlling the duty cycle of the Emission signal. Figure 8 is a brightness attenuation curve diagram of a sub-pixel in the EM signal off stage according to an embodiment of the present disclosure, such as Figure 8As shown, the photoelectric sensor 101 of the present disclosure is turned on during the off phase of the enable signal terminal EM to sense ambient light. The OLED device can be regarded as an equivalent circuit of a resistor and a capacitor in parallel. The capacitance of the device itself will affect its response speed to the voltage, that is, the larger the device capacitance, the longer the time it takes for the OLED device to reach the start-up potential under the same current. Similarly, under the condition of a constant discharge current, the discharge time also increases with the increase of the device capacitance. The capacitance of the Tandem OLED device itself is larger than that of the Single OLED device, which is affected by the larger capacitance of the Tandem OLED device itself, such as Figure 8 As shown in the t0 stage in FIG, after receiving the shutdown signal from the enable signal terminal EM, the discharge process of the Tandem OLED device will be slow, and the OLED brightness cannot be quickly reduced to the target value. As a result, the photoelectric sensor 101 senses the lateral light leakage of the sub-pixel when the enable signal terminal EM outputs the shutdown signal, thereby reducing the sensing accuracy of the ambient light.

[0078] The structure and principle of the display panel disclosed in the present invention are described in detail below.

[0079] In an exemplary embodiment, the multiple sub-pixels formed on the driving backplane 110 may generally include R sub-pixels, G sub-pixels and B sub-pixels, and the light absorption structure 120 disclosed herein may be arranged in a one-to-one correspondence with only one of the three sub-pixels in the above-mentioned photosensitive area 200. For example, the light absorption structure 120 may include a first light absorption structure 121, a second light absorption structure 122 and a third light absorption structure 123, wherein the first light absorption structure 121 is a light absorption structure arranged circumferentially around the G sub-pixel, the second light absorption structure 122 is a light absorption structure arranged circumferentially around the R sub-pixel, and the third light absorption structure 123 is a light absorption structure arranged circumferentially around the B sub-pixel.

[0080] For example, Figure 2 As shown, the display panel may include only the first light absorption structure 121, that is, the display panel includes only the light absorption structure arranged circumferentially around the G sub-pixel, and the first light absorption structure 121 may be arranged in a one-to-one correspondence with the G sub-pixel. Fig. 9 and Fig.10 As shown, Fig.10 for Fig. 9 In the cross-sectional view along the dotted line AA, the display panel may include only the third light absorption structure 123, that is, the display panel includes only the light absorption structure arranged circumferentially around the B sub-pixel, and the third light absorption structure 123 may be arranged one-to-one with the B sub-pixel. Or, Fig.11 and Fig.12 As shown, Fig.12 for Fig.11In the cross-sectional view along the dotted line AA, the display panel may include only the second light absorption structure 122, that is, the display panel includes only the light absorption structure circumferentially arranged around the R sub-pixel, and the second light absorption structure 122 may be arranged in a one-to-one correspondence with the R sub-pixel.

[0081] In other embodiments, the light absorption structure 120 may also be arranged in one-to-one correspondence with any two of the three sub-pixels in the photosensitive area 200, for example. Fig.13 and Fig.14 As shown, Fig.14 for Fig.13 In the cross-sectional view along the dotted line AA, the display panel may include a first light absorption structure 121 and a second light absorption structure 122 at the same time, and the first light absorption structure 121 may be arranged in a one-to-one correspondence with the G sub-pixel, and the second light absorption structure 122 may be arranged in a one-to-one correspondence with the R sub-pixel. Fig.15 and Fig.16 As shown, Fig.16 for Fig.15 In the cross-sectional view along the dotted line AA, the display panel may include both the second light absorption structure 122 and the third light absorption structure 123. The second light absorption structure 122 may be arranged in a one-to-one correspondence with the R sub-pixels, and the third light absorption structure 123 may be arranged in a one-to-one correspondence with the B sub-pixels. Fig.17 and Fig.18 As shown, Fig.18 for Fig.17 In the cross-sectional view along the dotted line AA, the display panel may also include a first light absorption structure 121 and a third light absorption structure 123, and the first light absorption structure 121 may be arranged in a one-to-one correspondence with the G sub-pixels, and the third light absorption structure 123 may be arranged in a one-to-one correspondence with the B sub-pixels.

[0082] In other embodiments, Fig.19 and Fig. 20 As shown, Fig. 20 for Fig.19 In the cross-sectional view along the dotted line AA, the display panel can also include a first light absorption structure 121, a second light absorption structure 122 and a third light absorption structure 123, that is, the three sub-pixels of R, G, and B in the photosensitive area 200 are all provided with a light absorption structure 120 corresponding thereto.

[0083] Generally, green light accounts for the largest proportion of white light and is mainly sensed by the photoelectric sensor 101. However, in the device structure, green light decays the slowest, so green light has the greatest impact on the sensing accuracy of the photoelectric sensor 101. Therefore, in the preferred embodiment of the present disclosure, when the photosensitive area 200 includes only one light absorption structure, it can be Figure 2As shown, the light absorption structure 121 is arranged one by one in the circumferential direction of the G sub-pixel to improve the lateral light leakage of the green light and enhance the sensing accuracy of the photosensor 101 for the ambient light. Alternatively, when the photosensitive area 200 includes two light absorption structures, it can be Fig.10 As shown in FIG. 1 , the second light absorption structure 122 is arranged one by one in the circumference of the R sub-pixel and the first light absorption structure 121 is arranged one by one in the circumference of the G sub-pixel, or as shown in FIG. Fig.12 As shown, the first light absorption structures 121 are arranged one-to-one around the G sub-pixels and the third light absorption structures 123 are arranged one-to-one around the B sub-pixels, and the sensing accuracy of the ambient light is improved by improving the light absorption effect of the green light.

[0084] like Figure 2 As shown, in an exemplary embodiment, when the photosensitive area 200 includes only the first light absorption structure 121, the minimum absorption wavelength of the first light absorption structure 121 is less than or equal to the minimum light emission wavelength of the G sub-pixel, and the maximum absorption wavelength of the first light absorption structure 121 is greater than or equal to the maximum light emission wavelength of the G sub-pixel.

[0085] For example, the material of the first light absorption structure 121 includes a compound represented by the following structural formula (1):

[0086]

[0087] For example, the compound of the structural formula (1) can be added to a polyimide precursor and the first light absorption structure 121 can be prepared through an exposure process. Fig.21 The absorption spectrum curve of the compound is shown as Fig.21 As shown, the compound has a strong absorption effect on the green light band. The first light absorption structure 121 formed in this way can absorb the lateral light leakage of the G sub-pixel to prevent the light from leaking to the photosensor 101.

[0088] In addition, the material of the first light absorption structure 121 can also be a black material. For example, the black material can be a black polyimide glue (PI), which can also be prepared by an exposure process to form the first light absorption structure 121. The black PI glue has strong light absorption in the 300-700nm band. Therefore, the first light absorption structure 121 formed can also absorb the lateral light leakage of the G sub-pixel to prevent light leakage to the photoelectric sensor 101. Furthermore, the material of the second light absorption structure 122 and the third light absorption structure 123 can also be a black material. The second light absorption structure 122 and the third light absorption structure 123 formed by black materials also have a good light absorption effect on the lateral light leakage of the R sub-pixel and the B sub-pixel.

[0089] Fig. 22FIG. 1 is a cross-sectional view of a light absorption structure and a sub-pixel according to an embodiment of the present disclosure, and shows three sub-pixels of R, G, and B. Fig. 22 As shown, the inner wall of the light absorption structure 120 can be in contact with the side wall of the first electrode ANO of the corresponding sub-pixel. Specifically, the inner wall of the light absorption structure 120 refers to the side wall of the light absorption structure 120 facing the sub-pixel surrounded by the light absorption structure 120. The first electrode ANO has a certain thickness in the thickness direction of the driving backplane 110, so that the first electrode ANO has a side wall facing the light absorption structure 120. The inner wall of the light absorption structure 120 is in contact with the side wall of the first electrode ANO of the corresponding sub-pixel, that is, the light absorption structure 120 is arranged circumferentially in contact with the side wall of the first electrode ANO of the corresponding sub-pixel. Therefore, under this structure, there is no gap between the light absorption structure 120 and the first electrode ANO surrounded by it. This structure can prevent some light at a specific angle from entering the photoelectric sensor 101 on the non-display side through the gap between the light absorption structure 120 and the first electrode ANO, so this structure can fully ensure the light absorption effect of the light absorption structure 120 for the lateral light leakage of the sub-pixel.

[0090] For example, due to the mask shadow problem, organic electroluminescent layer materials are usually left on the pixel definition layer PDL. The remaining luminescent layer materials will emit light under the lateral leakage of the OLED device. Figure 4 As shown, the light c generated by the residual light-emitting layer material may just pass through the gap between the light absorption structure 120 and the corresponding sub-pixel at a specific angle and be transmitted to the photosensor 101 on the non-display side. In this exemplary embodiment, because the inner wall of the light absorption structure 120 directly contacts the side wall of the first electrode ANO of the sub-pixel surrounded by it, the light absorption structure 120 can absorb light at extreme angles such as the light c, so that the light absorption structure 120 has the best light absorption effect.

[0091] Fig.23 is a cross-sectional view of a light absorption structure and a sub-pixel according to another embodiment of the present disclosure, Fig.24 is a cross-sectional view of a light absorption structure and a sub-pixel according to another embodiment of the present disclosure, as shown in FIG. Fig.23 and Fig.24 As shown, in an exemplary embodiment, the light absorption structure 120 may also partially overlap with the first electrode ANO, for example, Fig.23 As shown, part of the light absorption structure 120 is located on the first electrode ANO and part of it is located on the driving backplane; or as shown in FIG. Fig.24 As shown, the light absorption structure 120 is entirely located on the first electrode ANO. These all belong to the protection scope of the present disclosure.

[0092] Fig.25 is a top view of a light absorption structure and a sub-pixel according to another embodiment of the present disclosure, Fig.26for Fig.25 The cross-sectional view along the dotted line AA in FIG. 1 shows three sub-pixels in a pixel unit, and an exemplary description is given by taking the example that all three sub-pixels are provided with a light absorption structure 120. Fig.25 and Fig.26 As shown, in an exemplary embodiment, there may be a gap between the inner wall of the light absorption structure 120 and the side wall of the first electrode ANO of the corresponding sub-pixel, that is, the inner wall of the light absorption structure 120 does not contact the side wall of the first electrode ANO of the sub-pixel surrounded by it. Fig.25 As shown, the orthographic projection of the light absorption structure 120 on the driving backplane 110 is a ring, which surrounds the periphery of the orthographic projection of the corresponding sub-pixel on the driving backplane 110. In some embodiments, the orthographic projection of the light absorption structure 120 on the driving backplane 110 may be a circular ring or a regular polygonal ring, and the regular polygonal ring may be, for example, a rectangular ring, a regular pentagonal deformed ring, a regular hexagonal ring, etc. In other embodiments, the orthographic projection of the light absorption structure 120 on the driving backplane 110 may also be an irregular ring.

[0093] Fig. 27 for Fig.25 A partial enlarged view of a light-absorbing structure in Fig. 27 As shown, the light absorption structure 120 has a relative inner side L1 and outer side L2 on the positive projection of the driving backplane 110, and a first straight line k passing through any first node on the inner side L1 and extending along the first direction intersects with the outer side L2 at a second node, and the first node and the second node have a third width d3 in the first direction; there is a gap between the inner side L1 of the positive projection of the light absorption structure 120 on the driving backplane 110 and the edge of the positive projection of the first electrode ANO of the corresponding sub-pixel on the driving backplane 110, and the first straight line k intersects with the edge of the positive projection of the first electrode ANO on the driving backplane 110 at a third node, and the first node and the third node have a second width d2 in the first direction, and the second width d2 is less than or equal to the third width d3.

[0094] Among them, there is a third width d3 between the first node and the second node, and there is a second width d2 between the first node and the third node. The second width d2 reflects the gap width between the inner wall of the light absorption structure 120 and the first electrode ANO of the corresponding sub-pixel, and the third width d3 reflects the wall thickness of the light absorption structure 120. As described above, the orthographic projection of the light absorption structure 120 on the driving backplane 110 can be a circular ring or a polygonal ring. When the orthographic projection of the light absorption structure 120 on the driving backplane 110 is a circular ring, the first straight line k is not tangent to the inner side L1; when the orthographic projection of the light absorption structure 120 on the driving backplane 110 is a polygonal ring, the first straight line k intersects with the inner side L1. In this way, it is ensured that the first straight line k can have intersections with the inner side L1, the outer side L2 and the orthographic projection edge of the first electrode ANO.

[0095] The second width d2 is less than or equal to the third width d3, indicating that the thickness of the light absorption structure 120 is greater than the gap width between the light absorption structure 120 and the first electrode ANO of the corresponding sub-pixel.

[0096] In particular, such as Fig.28 As shown in FIG. 1 , when the positive projection of the light absorption structure 120 on the driving back plate 110 is a ring and the first straight line k passes through the center of the ring, or as shown in FIG. Fig.29 As shown, when the positive projection of the light absorbing structure 120 on the driving backplane 110 is a polygonal ring and the first straight line k is perpendicular to the inner side L1, the third width d3 has a minimum value recorded as the first width d1. Obviously, the first width d1 is the wall thickness of the light absorbing structure 120. At this time, the second width d2 is less than or equal to the first width d1, that is, the wall thickness of the light absorbing structure 120 must be greater than or equal to the gap width between the light absorbing structure 120 and the first electrode ANO of the corresponding sub-pixel. Because the wall thickness of the light absorbing structure 120 is small, when the first width d1 is less than or equal to the second width d2, it indicates that the gap between the light absorbing structure 120 and the corresponding sub-pixel is also small, so that the amount of light transmitted to the photoelectric sensor 101 through the gap can be reduced, which is conducive to improving the absorption effect of the light absorbing structure 120 on the lateral light leakage of the sub-pixel.

[0097] In some embodiments, the ratio of the second width d2 to the first width d1 may be greater than or equal to 0 and less than or equal to 1, for example, it may be 0, 1 / 10, 1 / 9, 1 / 8, 1 / 7, 1 / 6, 1 / 5, 1 / 4, 1 / 3, 1 / 2, 1, etc. In particular, when there is no gap between the inner wall of the light absorption structure 120 and the first electrode ANO of the corresponding sub-pixel, that is, when the inner wall of the light absorption structure 120 directly contacts the edge of the first electrode ANO of the corresponding sub-pixel, the second width d2 is 0, and accordingly, the ratio of the second width d2 to the first width d1 is 0. When the wall thickness of the light absorption structure 120 is small, the wall thickness of the light absorption structure 120 may be the same as the gap width between the inner wall of the light absorption structure 120 and the first electrode ANO of the corresponding sub-pixel.

[0098] By setting the gap width between the inner wall of the light absorption structure 120 and the side wall of the first electrode ANO in accordance with the width of the light absorption structure 120 in accordance with the above-mentioned proportional relationship, the distance between the inner wall of the light absorption structure 120 and the edge of the first electrode ANO of the corresponding sub-pixel can be made small enough, thereby avoiding the situation where the gap width between the inner wall of the light absorption structure 120 and the first electrode ANO is too large, causing part of the light to be transmitted to the photoelectric sensor 101 through the gap, thereby improving the absorption effect of lateral light leakage generated by the sub-pixel.

[0099] For example, in some embodiments, the first width d1 may be greater than or equal to 0.5 μm and less than or equal to 2 μm, for example, it may be 0.5 μm, 0.6 μm, 0.8 μm, 1 μm, 1.2 μm, 1.4 μm, 1.5 μm, 1.6 μm, 1.8 μm, 2.0 μm, etc. Correspondingly, the second width d2 may be greater than or equal to 0 and less than or equal to 0.5 μm, for example, it may be 0, 0.2 μm, 0.4 μm, 0.5 μm, etc.

[0100] In addition, it should be understood that in the thickness direction of the driving back plate 110, the wall thickness of the light absorption structure 120 may be gradual, for example, it may be a structure that is narrow at the top and wide at the bottom, or it may be a structure that is wide at the top and narrow at the bottom. In this case, the wall thickness of the light absorption structure 120 refers to the maximum thickness of the light absorption structure 120. For example, the wall thickness of the light absorption structure 120 gradually decreases in the direction away from the driving back plate 110, and the first width d1 is the thickness of the bottom surface of the light absorption structure 120 in contact with the driving back plate 110; or, the wall thickness of the light absorption structure 120 gradually increases in the direction away from the driving back plate 110, and the first width d1 is the thickness of the top surface of the light absorption structure 120 away from the driving back plate 110.

[0101] Fig.30 is a cross-sectional view of a light absorption structure and a sub-pixel according to an embodiment of the present disclosure, Fig.31 for Fig.30 A partial enlarged view of the light-absorbing structure in the Fig.30 and Fig.31 As shown, the light absorption structure 120 may include a first structure layer M1 and a second structure layer M2 parallel to the driving backplane 110, the first structure layer M1 is located at any position on the side of the second structure layer M2 away from the driving backplane 110, and the orthographic projection of the first structure layer M1 on the driving backplane 110 is located within the orthographic projection of the second structure on the driving backplane 110. Among them, the first structure layer M1 and the second structure layer M2 can be understood as a planar structure formed by cutting the light absorption structure 120 with a plane parallel to the driving backplane 110. The first structure layer M1 is located at any position on the side of the second structure layer M2 away from the driving backplane 110, that is, at Fig.30 In the structure shown, the first structure layer M1 is located on the upper part of the second structure layer M2. The orthographic projection of the first structure layer M1 on the driving backplane 110 is located within the orthographic projection of the second structure layer M2 on the driving backplane 110, indicating that the light absorption structure 120 is a structure that is narrow at the top and wide at the bottom. In other words, the sidewall of the light absorption structure 120 forms a climbing structure from the bottom close to the driving backplane 110 to the top away from the driving backplane 110.

[0102] Fig.32 is a cross-sectional view of a light absorption structure and a sub-pixel according to another embodiment of the present disclosure, Fig.33 for Fig.32 A partial enlarged view of the light-absorbing structure in the Fig.32 and Fig.33 As shown, the light absorption structure 120 includes a first structure layer M1 and a second structure layer M2 parallel to the driving backplane 110, the first structure layer M1 is located at any position on the side of the second structure layer M2 away from the driving backplane 110, and the orthographic projection of the first structure layer M1 on the driving backplane 110 overlaps with the orthographic projection of the second structure on the driving backplane 110. At this time, the size of the light absorption structure 120 at different positions in the thickness direction of the driving backplane 110 is the same, that is, the light absorption structure 120 is a structure of equal width from top to bottom. The structure of equal width from top to bottom is easy to realize in process, which can reduce the difficulty of the preparation process.

[0103] Continue to refer Figure 30 to Figure 33 , there is a slope angle α between the side wall and the bottom surface of the light absorbing structure 120, and the slope angle α is greater than or equal to 20° and less than or equal to 90°, for example, it can be 20°, 30°, 40°, 45°, 50°, 60°, 70°, 80°, etc. As described above, the light absorbing structure 120 has a bottom surface close to the driving back plate 110 and a top surface away from the driving back plate 110 in the thickness direction of the driving back plate 110. In this exemplary embodiment, the slope angle α can be understood as: the first tangent plane perpendicular to the driving back plate 110 in the thickness direction of the driving back plate 110 intersects with the outer side wall of the light absorbing structure 120 at the fourth side L4 and intersects with the bottom surface of the light absorbing structure 120 at the fifth side L5, and there is a first angle between the fourth side L4 and the fifth side L5, and the first angle is the slope angle α of the light absorbing structure 120. The first cutting plane is perpendicular to the plane where the driving backplane 110 is located, which is equivalent to cutting the light absorbing structure 120 with the first cutting plane to form a fourth side L4 and a fifth side L5 on the side and bottom of the light absorbing structure 120, respectively. Therefore, the first angle between the fourth side L4 and the fifth side L5 is the slope angle α of the light absorbing structure 120. When the slope angle α is 90°, it is formed. Fig.33 The light absorption structure 120 shown in the figure has the same width at the top and bottom. When the slope angle α is less than 90°, a Fig.31 The light absorbing structure 120 shown is narrow at the top and wide at the bottom.

[0104] It is understandable that, when the height of the light absorption structure 120 is constant, the smaller the slope angle of the light absorption structure 120, the wider the lateral width of the light absorption structure 120, resulting in a larger space between two adjacent first electrodes ANO occupied by the light absorption structure 120, resulting in a reduction in the effective light transmission area of ​​the pixel definition layer PDL in the photosensitive area 200, which is equivalent to reducing the aperture ratio of the photosensitive area 200, resulting in a reduction in the light transmittance of the photosensitive area 200. In display products, for example, in some terminal devices, the photosensitive area 200 usually corresponds to the distance sensor area, or in some terminals, the photosensitive area 200 has an overlapping area with the under-screen fingerprint area. When the light transmittance of the pixel definition layer PDL in the photosensitive area 200 is reduced, it will affect the normal operation of the distance sensor and the under-screen fingerprint sensor. Therefore, this exemplary embodiment sets the slope angle α of the light absorption structure 120 based on the above-mentioned angle range, which can shrink the lateral width of the light absorption structure 120, thereby reducing the space between adjacent first electrodes ANO occupied by the light absorption structure 120 and reducing the impact on the transmittance of the photosensitive area 200, thereby ensuring that the photosensitive area 200 has better transmittance.

[0105] Fig.34 is a cross-sectional view of a light absorption structure and a sub-pixel according to another embodiment of the present disclosure, Fig.35 for Fig.34 A partial enlarged view of the light-absorbing structure in the Fig.34 and Fig.35 As shown, the light absorption structure 120 includes a first structure layer M1 and a second structure layer M2 which are parallel to the driving backplane 110, and the first structure layer M1 is located at any position of the second structure layer M2 on the side away from the driving backplane 110; wherein, the orthographic projection of the second structure layer M2 on the driving backplane 110 is located within the orthographic projection of the first structure layer M1 on the driving backplane 110. That is, the light absorption structure 120 in this exemplary embodiment forms a structure which is wide at the top and narrow at the bottom. It can be understood that the lateral light leakage generated by the sub-pixels will be emitted at different angles. When some light rays are incident on the top of the pixel defining layer PDL at a certain angle, they will pass through the pixel defining layer PDL and be reflected by the second electrode layer above the pixel defining layer PDL. After being reflected by the second electrode layer, they may further be incident on the photoelectric sensor 101 on the back of the display panel via the pixel defining layer PDL. For example, Figure 4The light a and the light d in the image will be reflected back to the pixel defining layer PDL by the second electrode layer after passing through the pixel defining layer PDL, and will pass through the pixel defining layer PDL and be transmitted to the photosensor 101 on the non-display side. It can be seen that the light d is closer to the sub-pixel than the light a, that is, the incident angle of the light d is smaller, which may cause this type of light with a smaller incident angle to be reflected by the second electrode layer and transmitted to the photosensor 101, that is, this type of light with a smaller incident angle may escape the light absorption structure 120. In this exemplary embodiment, the light absorption structure 120 is formed into a structure that is wide at the top and narrow at the bottom. In this way, because the top of the light absorption structure 120 is wider, its top can cover those light with a smaller incident angle to prevent these light from escaping. That is, under this structure, the light absorption structure 120 can block the lateral light leakage of the sub-pixel within a larger angle range. Therefore, compared with the above Fig.30 or Fig.32 The light absorption structure 120 shown in the exemplary embodiment has a better light absorption effect on the lateral light leakage of the sub-pixel, which is more conducive to improving the ambient light sensing accuracy of the photosensor 101.

[0106] like Fig.34 As shown, in this exemplary embodiment, the slope angle α between the side wall and the bottom surface of the light absorption structure 120 can be greater than 90° and less than or equal to 160°, for example, it can be 100°, 110°, 120°, 130°, 140°, 150°, 160°, etc. The meaning of the slope angle can be referred to the introduction of the above embodiment, which will not be repeated here. In this exemplary embodiment, by setting the slope angle of the light absorption structure 120 to the above range, on the one hand, Fig.30 The structure shown is similar, which can shrink the width of the light absorption structure 120 and occupy a smaller pixel definition layer PDL space, thereby reducing the impact on the transmittance of the photosensitive area 200. On the other hand, the increase in the slope angle can expand the top surface width of the light absorption structure 120, thereby increasing the coverage angle of the lateral light leakage transmitted to the second electrode layer.

[0107] like Fig.30 , Fig.32 and Fig.34As shown, in an exemplary embodiment, in the thickness direction of the driving backplane 110, the light absorption structure 120 may penetrate the pixel definition layer PDL, that is, the top surface of the light absorption structure 120 and the top surface of the pixel definition layer PDL are located in the same plane parallel to the driving backplane 110. The top surface of a certain structure described here can be understood as that the structure has a first end surface and a second end surface, the first end surface is in contact with the driving backplane 110, and the second end surface is opposite to the first end surface in the thickness direction of the driving backplane 110, and the second end surface is the top surface of the structure. By setting the light absorption structure 120 to penetrate the pixel defining layer PDL, on the one hand, the light absorption structure 120 can directly absorb the light that is self-luminous due to lateral leakage of the luminescent material remaining on the pixel defining layer PDL, and on the other hand, in the thickness direction of the driving backplane, the light absorption structure 120 can block the light that leaks laterally to the second electrode layer within a larger angle range, thereby preventing this part of the light from being reflected by the second electrode layer and then transmitted to the photoelectric sensor 101. Therefore, by setting the light absorption structure 120 to penetrate the pixel defining layer PDL, it is more conducive to enhancing the light absorption effect of the light absorption structure 120 on lateral light leakage.

[0108] Of course, in other embodiments of the present disclosure, in the thickness direction of the driving backplane 110, the light absorption structure 120 may not penetrate the pixel definition layer PDL. Specifically, the light absorption structure 120 has a top surface and a bottom surface that are relatively arranged in the thickness direction of the driving backplane, and the bottom surface of the light absorption structure 120 is closer to the driving backplane than the top surface. For example, the bottom surface of the light absorption structure 120 may be located on the driving backplane and / or on the first electrode ANO, and the pixel definition layer PDL covers the top surface of the light absorption structure 120. The top surface and the bottom surface of the light absorption structure 120 may have a first thickness. As described above, the display panel may further include a second electrode layer (the second electrode layer may be, for example, a cathode layer), the second electrode layer is located on the side of the pixel definition layer away from the driving backplane, and at least one side of the pixel definition layer PDL contacts the second electrode layer and the other side contacts the driving backplane, and the pixel definition layer PDL has a second thickness at the position where it contacts the second electrode layer, and the first thickness is less than the second thickness. That is, the height of the light absorption structure is less than the thickness of the pixel definition layer PDL.

[0109] Taking into account that the light absorption structure 120 has a certain wall thickness, only a very small part of the light can be reflected by the second electrode layer to the photoelectric sensor 101. Therefore, by reducing the thickness difference between the first thickness and the second thickness, for example, the ratio of the first thickness to the second thickness is greater than or equal to 0.6, for example, it can be 0.6, 0.7, 0.8, 0.9, etc., when the top of the light absorption structure is covered by the pixel defining layer PDL, the light absorption structure 120 can also have a good light absorption effect.

[0110] The present disclosure also provides a method for preparing a display panel, which can be used to prepare the display panel described in any of the above embodiments of the present disclosure, and the method may include the following steps:

[0111] S110, such as Fig.36 As shown, a driving backplane 100 is provided. The specific structure of the driving backplane 100 is not described in detail here.

[0112] S120, such as Fig.37 As shown, a plurality of light absorption structures 120 are formed in at least a partial area of ​​one side of the driving backplane 100, wherein the minimum light absorption wavelength of the light absorption structure 120 is less than or equal to the minimum light emission wavelength of the corresponding sub-pixel, and the maximum light absorption wavelength of the light absorption structure 120 is greater than or equal to the maximum light emission wavelength of the corresponding sub-pixel.

[0113] like Fig.37 As shown, in an exemplary embodiment, before forming the light absorption structure 120, an organic material can be driven to deposit on one side of the backplane 100 to form a planarization layer PLN, and then a metal material is deposited on the planarization layer PLN to form a first electrode layer, and then the first electrode layer is patterned to form a plurality of first electrodes ANO distributed in an array, and the first electrode ANO can be an anode.

[0114] After forming the first electrode ANO, a material having a light absorbing medium can be deposited on the photosensitive area 200 by a deposition process to form a light absorbing layer, and then the light absorbing layer is patterned by an exposure mask process to obtain a light absorbing structure 120, which can be arranged around the first electrode ANO. The specific working principle and structural features of the light absorbing structure 120 can be referred to the introduction of the above embodiment, which will not be repeated here.

[0115] S130, such as Fig.38 As shown, a pixel definition layer PDL is formed on one side of the driving backplane 100 , and the pixel definition layer PDL may be formed by depositing an organic material through a deposition process.

[0116] S140 , forming pixel openings in the pixel definition layer PDL using a patterning process, wherein the light absorption structure 120 is circumferentially arranged around the corresponding pixel openings.

[0117] S150, such as Fig.39 As shown, a light-emitting functional layer is formed in the pixel opening by using an evaporation process. The formation process of the light-emitting functional layer will not be described in detail here.

[0118] In an exemplary embodiment, after forming the light-emitting functional layer, an encapsulation layer may be further formed, and the encapsulation layer may include a first inorganic encapsulation layer, an organic encapsulation layer, and a second inorganic encapsulation layer. Then, a touch control layer is formed on the encapsulation layer.

[0119] The present disclosure also provides a display device, which may include the display panel described in any of the above embodiments.

[0120] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing the invention disclosed herein. The present disclosure is intended to cover any variations, uses or adaptations of the present disclosure, which follow the general principles of the present disclosure and include common knowledge or customary techniques in the art that are not disclosed in the present disclosure. The description and examples are intended to be exemplary only, and the true scope and spirit of the present disclosure are indicated by the appended claims.

Claims

1. A display panel, characterized in that: include: A driving backplane, wherein a plurality of sub-pixels emitting light of different colors are formed on one side of the driving backplane; A pixel defining layer, located on one side of the driving backplane, the pixel defining layer having a pixel opening, and a light-emitting functional layer of the sub-pixel is formed in the pixel opening; A plurality of light absorption structures are arranged corresponding to at least some of the sub-pixels, the light absorption structures are located in the pixel definition layer and are arranged circumferentially around the corresponding pixel openings, the minimum light absorption wavelength of the light absorption structure is less than or equal to the minimum light emission wavelength of the sub-pixel corresponding thereto, and the maximum light absorption wavelength of the light absorption structure is greater than or equal to the maximum light emission wavelength of the sub-pixel corresponding thereto.

2. The display panel according to claim 1, characterized in that: The display panel has a photosensitive area, and the photosensitive area has a photoelectric sensor; Wherein, the light absorption structure is arranged corresponding to at least part of the sub-pixels of the photosensitive area.

3. The display panel according to claim 1, characterized in that: The photosensitive area includes an R sub-pixel, a G sub-pixel and a B sub-pixel, and the light absorption structure includes a first light absorption structure; The first light absorption structure is arranged corresponding to at least part of the G sub-pixels, the minimum light absorption wavelength of the first light absorption structure is less than or equal to the minimum light emission wavelength of the G sub-pixels, and the maximum light absorption wavelength of the first light absorption structure is greater than or equal to the maximum light emission wavelength of the G sub-pixels.

4. The display panel according to claim 3, characterized in that: The minimum absorption wavelength of the first light absorption structure is also less than or equal to the minimum emission wavelength of the B sub-pixel, and the maximum absorption wavelength of the first light absorption structure is also greater than or equal to the maximum emission wavelength of the B sub-pixel.

5. The display panel according to claim 1, characterized in that: The photosensitive area includes an R sub-pixel, a G sub-pixel and a B sub-pixel, and the light absorption structure includes two light absorption structures among a first light absorption structure, a second light absorption structure and a third light absorption structure; The first light absorption structure is arranged at least corresponding to a part of the G sub-pixels, the second light absorption structure is arranged at least corresponding to a part of the R sub-pixels, and the third light absorption structure is arranged at least corresponding to a part of the B sub-pixels.

6. The display panel according to claim 1, characterized in that: The photosensitive area includes an R sub-pixel, a G sub-pixel and a B sub-pixel, and the light absorption structure includes a first light absorption structure, a second light absorption structure and a third light absorption structure; The first light absorption structure is arranged at least corresponding to a part of the G sub-pixels, the second light absorption structure is arranged at least corresponding to a part of the R sub-pixels, and the third light absorption structure is arranged at least corresponding to a part of the B sub-pixels.

7. The display panel according to any one of claims 3 to 6, characterized in that: The first light absorption structure, the second light absorption structure and the third light absorption structure have the same minimum absorption wavelength and the same maximum absorption wavelength, and the minimum absorption wavelength of any light absorption structure is greater than or equal to the minimum light emission wavelength of the B sub-pixel, and the maximum absorption wavelength is also greater than or equal to the maximum light emission wavelength of the B sub-pixel.

8. The display panel according to claim 1, characterized in that: The material of the light-absorbing structure includes a compound represented by the following structural formula (1): Alternatively, the material of the light absorption structure is a black material.

9. The display panel according to claim 1, characterized in that: The display panel further includes: A first electrode layer, comprising a plurality of first electrodes distributed in an array, wherein the pixel defining layer has the pixel opening at the first electrode, and the light-emitting functional layer is formed on a side of the first electrode away from the driving backplane; The orthographic projection of the light absorption structure on the driving backplane at least partially overlaps with the orthographic projection of the first electrode on the driving backplane.

10. The display panel according to claim 1, characterized in that: The display panel further includes: A first electrode layer, comprising a plurality of first electrodes distributed in an array, wherein the pixel defining layer has the pixel opening at the first electrode, and the light-emitting functional layer is formed on a side of the first electrode away from the driving backplane; The orthographic projection of the light absorption structure on the driving backplane does not overlap with the orthographic projection of the first electrode on the driving backplane.

11. The display panel according to claim 1, characterized in that: The display panel further includes: A first electrode layer, comprising a plurality of first electrodes distributed in an array, wherein the pixel defining layer has the pixel opening at the first electrode, and the light-emitting functional layer is formed on a side of the first electrode away from the driving backplane; Wherein, the light absorption structure contacts the side wall of the corresponding first electrode.

12. The display panel according to claim 1, characterized in that: The display panel further includes: A first electrode layer, comprising a plurality of first electrodes distributed in an array, wherein the pixel defining layer has the pixel opening at the first electrode, and the light-emitting functional layer is formed on a side of the first electrode away from the driving backplane; The minimum width of the light absorption structure on the orthographic projection of the driving backplane is the first width, and there is a gap between the light absorption structure and the corresponding first electrode, and the gap width is less than or equal to the first width.

13. The display panel according to claim 12, characterized in that: A ratio of the gap width to the first width is greater than 0 and less than or equal to 1.

14. The display panel according to claim 1, characterized in that: The light absorption structure penetrates the pixel defining layer in the thickness direction of the driving backplane.

15. The display panel according to claim 1, characterized in that: The light absorption structure has a bottom surface and a top surface which are arranged opposite to each other in the thickness direction of the driving backplane, the bottom surface is located on a side of the top surface close to the driving backplane, and the pixel defining layer covers the top surface of the light absorption structure.

16. The display panel according to claim 15, characterized in that: The display panel further includes: A second electrode layer is located on a side of the pixel definition layer away from the driving backplane, and at least one side of a portion of the pixel definition layer contacts the second electrode layer and the other side contacts the driving backplane; Among them, in the thickness direction of the driving backplane, the light absorption structure has a first thickness between the top and bottom surfaces, the pixel defining layer has a second thickness at a position contacting the second electrode layer, and the ratio of the first thickness to the second thickness is greater than or equal to 0.

6.

17. The display panel according to claim 1, characterized in that: The light absorption structure comprises a first structure layer and a second structure layer which are parallel to the driving backplane, and the first structure layer is located at any position of the second structure layer on a side away from the driving backplane; The orthographic projection of the first structure layer on the driving backplane is located within the orthographic projection of the second structure layer on the driving backplane, or, The orthographic projection of the first structure layer on the driving backplane overlaps with the orthographic projection of the second structure layer on the driving backplane.

18. The display panel according to claim 1, characterized in that: The light absorption structure comprises a first structure layer and a second structure layer which are parallel to the driving backplane, and the first structure layer is located at any position of the second structure layer on a side away from the driving backplane; The orthographic projection of the second structural layer on the driving backplane is located within the orthographic projection of the first structural layer on the driving backplane.

19. The display panel according to claim 17 or 18, characterized in that: The orthographic projection of the light absorbing structure on the driving back plate is a circular ring or a regular polygonal ring.

20. The display panel according to claim 17 or 18, characterized in that: The light absorption structure has a first width as a minimum width of an orthographic projection on the driving backplane. The first width is greater than or equal to 0.5 μm and less than or equal to 2 μm.

21. The display panel according to claim 17, characterized in that: The slope angle formed by the side wall and the bottom surface of the light absorption structure is greater than or equal to 20° and less than or equal to 90°.

22. The display panel according to claim 18, characterized in that: The slope angle formed by the side wall and the bottom surface of the light absorption structure is greater than 90° and less than or equal to 160°.

23. The display panel according to claim 2, characterized in that: The sub-pixel at least includes a first light-emitting unit and a second light-emitting unit stacked on one side of the driving backplane, and the first light-emitting unit is connected in series via a charge generation layer; The sub-pixel has a light-emitting phase and a non-light-emitting phase, and the photosensor located in the photosensitive area has a sensing phase and a non-sensing phase, wherein the sensing phase of the photosensor does not overlap with the light-emitting phase of the sub-pixel.

24. A method for preparing a display panel, characterized in that: For preparing the display panel according to any one of claims 1 to 23, the method comprises: Provide drive backplane; A plurality of light absorption structures are formed in at least a portion of a side of the driving backplane, wherein the minimum light absorption wavelength of the light absorption structure is less than or equal to the minimum light emission wavelength of the sub-pixel corresponding thereto, and the maximum light absorption wavelength of the light absorption structure is greater than or equal to the maximum light emission wavelength of the sub-pixel corresponding thereto; forming a pixel defining layer on one side of the driving backplane; Forming a pixel opening in the pixel definition layer by a patterning process, wherein the light absorption structure is circumferentially arranged around the corresponding pixel opening; A light-emitting functional layer is formed in the pixel opening by using an evaporation process.

25. A display device, characterized in that: A display panel comprising any one of claims 1-23.

Images