Display panel and display device

The display panel addresses stray light issues by using light-blocking and filter layers to improve fingerprint recognition accuracy in OLED displays by reducing ambient light impact on thin film transistors and photosensitive elements.

JP7776990B2Active Publication Date: 2025-11-27BOE TECHNOLOGY GROUP CO LTD
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Patent Information

Application Number
JP2021567868
Authority / Receiving Office
JP · JP
Patent Type
Patents
Current Assignee / Owner
Filing Date
2020-02-13
Publication Date
2025-11-27
Estimated Expiration
2040-02-13

AI Technical Summary

Technical Problem

Existing OLED displays with integrated fingerprint sensors face issues due to high stray light transmittance, which saturates the sensor's photodiode and reduces contrast, and thin film transistors experience increased leakage current under strong light, affecting fingerprint recognition performance.

Method used

The display panel incorporates a light-blocking element between the driving circuit layer and light-emitting elements, a photosensitive element between adjacent light-emitting elements, and a filter layer to block ambient light, reducing stray light impact on the photosensitive element and thin film transistors.

Benefits of technology

This configuration effectively reduces ambient light saturation and leakage current, enhancing the sensitivity and accuracy of fingerprint recognition by minimizing stray light interference.

✦ Generated by Eureka AI based on patent content.

Smart Images

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Patent Text Reader

Abstract

A display panel and a display device are disclosed, the display panel including a substrate, a plurality of first thin film transistors and second thin film transistors disposed on the substrate, the second thin film transistors being disposed between adjacent first thin film transistors of the plurality of first thin film transistors, a driving circuit layer disposed on a side of the driving circuit layer away from the substrate and electrically connected to the plurality of first thin film transistors, a plurality of light-emitting elements disposed between adjacent light-emitting elements of the plurality of light-emitting elements and electrically connected to the second thin film transistors, and a light-shielding element disposed in an optical path along which ambient light from outside the display panel propagates to a thin film transistor channel of the second thin film transistor within the display panel, thereby reducing the ambient light propagating to the thin film transistor channel of the second thin film transistor.
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Description

[Technical Field]

[0001] The present disclosure relates to the field of display technology, and more particularly to display panels and display devices. [Background technology]

[0002] In some related technologies, fingerprint recognition function is integrated into an organic light-emitting diode (OLED) display, where a photosensitive element as a fingerprint sensor is disposed above an OLED backplate and between multiple OLED light-emitting pixels. Summary of the Invention [Means for solving the problem]

[0003] According to one aspect of the present disclosure, A substrate; a driving circuit layer including a plurality of first thin film transistors and second thin film transistors disposed on the substrate, the second thin film transistors being disposed between adjacent first thin film transistors of the plurality of first thin film transistors; a plurality of light-emitting elements disposed on a side of the driving circuit layer away from the substrate, the light-emitting elements being electrically connected to the plurality of first thin film transistors, respectively; a photosensitive element disposed between adjacent light-emitting elements among the plurality of light-emitting elements and electrically connected to the second thin film transistor; a light-blocking element disposed in an optical path along which ambient light from outside the display panel propagates to a thin film transistor channel of the second thin film transistor within the display panel, thereby reducing the ambient light propagating to the thin film transistor channel of the second thin film transistor; Including, Regarding the display panel.

[0004] In some embodiments, at least one of the plurality of light-emitting elements is an organic light-emitting diode, the organic light-emitting diode includes an anode layer electrically connected to a first electrode of the first thin film transistor, a second electrode of the second thin film transistor is disposed in the same layer as the first electrode of the first thin film transistor, the light-shielding element includes an extension portion of the second electrode extending toward the first electrode, and an orthogonal projection of the extension portion onto the substrate at least partially overlaps with an orthogonal projection of the anode layer onto the substrate.

[0005] In some embodiments, an orthogonal projection of the photosensitive element onto the substrate does not overlap with an orthogonal projection of the anode layer onto the substrate.

[0006] In some embodiments, the organic light-emitting diode further includes a planarization layer disposed between the driving circuit layer and the plurality of light-emitting elements, the photosensitive element being disposed within the planarization layer, and an anode layer of the organic light-emitting diode being disposed on a side of the planarization layer away from the driving circuit layer and electrically connected to a first electrode of the first thin film transistor through a via hole in the planarization layer.

[0007] In some embodiments, the substrate is a glass substrate, and the light blocking element includes a light absorbing layer disposed on a surface of the glass substrate away from the drive circuit layer.

[0008] In some embodiments, the second thin film transistor further includes an active layer disposed on a side of the substrate closer to the photosensitive element and a first gate layer disposed on a side of the active layer away from the substrate, and the light-shielding element includes a second gate layer disposed between the substrate and the active layer, and at least a portion of an orthogonal projection onto the substrate overlaps with an orthogonal projection of the first gate layer onto the substrate.

[0009] In some embodiments, the light-shielding element includes a first light-shielding layer, which is disposed between the driving circuit layer and the plurality of light-emitting elements as a planarization layer and is used to block ambient light from entering the driving circuit layer.

[0010] In some embodiments, the photosensitive element is disposed in the first light-shielding layer and is exposed on a side of the first light-shielding layer away from the drive circuit layer.

[0011] In some embodiments, the pixel array further includes a planarization layer disposed between the driving circuit layer and the plurality of light-emitting elements, and a pixel definition layer disposed on a side of the planarization layer away from the driving circuit layer, wherein a material of at least one of the planarization layer and the pixel definition layer is a filter material configured to block light having a wavelength higher than a set wavelength and to transmit light having a wavelength equal to or lower than the set wavelength.

[0012] In some embodiments, the device further includes a filter layer arranged on a side of the photosensitive element away from the drive circuit layer, the material of the filter layer being a filter material configured to block light of wavelengths higher than a set wavelength and transmit light of wavelengths equal to or lower than the set wavelength, and at least a portion of an orthogonal projection of the filter layer onto the substrate overlaps with an orthogonal projection of the photosensitive element onto the substrate.

[0013] In some embodiments, the light-blocking element includes a second light-blocking layer, the second light-blocking layer being disposed as a pixel definition layer on a side of the driving circuit layer away from the substrate, and the filter layer being provided in the second light-blocking layer and exposed on a side of the second light-blocking layer away from the driving circuit layer.

[0014] In some embodiments, the set wavelength is between 550 nm and 620 nm.

[0015] In some embodiments, the set wavelength is 600 nm.

[0016] In some embodiments, at least one of the plurality of light-emitting elements is an organic light-emitting diode, and the organic light-emitting diode includes: an anode layer disposed between the pixel definition layer and the planarization layer and having a portion exposed to at least one of the plurality of openings; an organic light-emitting layer disposed in at least one of the plurality of openings and covering a surface of the exposed portion of the anode layer; and a cathode layer covering surfaces of the pixel definition layer and the organic light-emitting layer.

[0017] In some embodiments, the photosensitive element includes an N-type amorphous silicon layer, an amorphous silicon layer, and a P-type amorphous silicon layer stacked in order along a direction away from the driving circuit layer.

[0018] In some embodiments, the photosensitive element is used for fingerprint authentication.

[0019] Another aspect of the present disclosure relates to a display device including a display panel as described above.

[0020] The drawings which form a part of the specification illustrate embodiments of the present disclosure and, together with the description, serve to explain the principles of the disclosure.

[0021] The present disclosure can be more clearly understood from the following detailed description, taken in conjunction with the drawings, in which: [Brief explanation of the drawings]

[0022] [Figure 1] 1 is a schematic cross-sectional view of an embodiment of a display panel according to the present disclosure. [Figure 2] 1 is a schematic cross-sectional view of an embodiment of a display panel according to the present disclosure. [Figure 3] 1 is a schematic cross-sectional view of an embodiment of a display panel according to the present disclosure. [Figure 4] 1 is a schematic cross-sectional view of an embodiment of a display panel according to the present disclosure. [Figure 5] 1 is a schematic cross-sectional view of an embodiment of a display panel according to the present disclosure. [Figure 6]1 is a schematic cross-sectional view of an embodiment of a display panel according to the present disclosure. [Figure 7] 1 is a schematic cross-sectional view of an embodiment of a display panel according to the present disclosure. [Figure 8] 1 is a schematic cross-sectional view of an embodiment of a display panel according to the present disclosure. [Figure 9] 1 is a schematic cross-sectional view of an embodiment of a display panel according to the present disclosure. [Figure 10] 1 is a schematic cross-sectional view of an embodiment of a display panel according to the present disclosure.

[0023] It should be understood that the dimensions of the various parts shown in the drawings are not drawn to scale, and the same or similar reference numerals denote the same or similar components. DETAILED DESCRIPTION OF THE INVENTION

[0024] Various exemplary embodiments of the present disclosure will be described in detail with reference to the drawings. The description of the exemplary embodiments is merely illustrative and does not limit the present disclosure and its application or use. The present disclosure is not limited to the embodiments described herein, but can be embodied in many different forms. These embodiments are provided to make the disclosure thorough and complete, and to fully convey the scope of the disclosure to those skilled in the art. It should be noted that, unless otherwise specified, the relative arrangement of parts and steps, material components, formulas, and numerical values ​​described in these embodiments should be construed as merely illustrative, not limiting.

[0025] As used in this disclosure, "first," "second," and similar words do not denote order, number, or importance, but are merely used to distinguish different parts. Similar words such as "comprise" or "contain" mean that the elements preceding the term cover the elements listed after the term, and do not exclude the possibility of covering other elements. "Top," "bottom," "left," "right," and the like, denote only relative positional relationships; if the absolute positions of the described objects are changed, the relative positional relationships may also be changed accordingly.

[0026] In this disclosure, when it is described that a specific device is disposed between a first device and a second device, there may or may not be an intermediate device between the specific device and the first or second device. When it is described that a specific device is connected to another device, the specific device may be directly connected to the other device without an intermediate device, or may be connected to the other device without an intermediate device.

[0027] Unless otherwise defined, all terms used in this disclosure (including technical or scientific terms) have the same meaning as understood by a person skilled in the art to which this disclosure belongs. It should also be understood that terms defined in a general dictionary should be interpreted as having a meaning consistent with the meaning in the context of the relevant art, and should not be interpreted in an idealized or overly formalized sense, unless explicitly defined herein.

[0028] Techniques, methods, and apparatus known to those skilled in the relevant art may not be described in detail, but where appropriate, said techniques, methods, and apparatus should be considered part of the specification.

[0029] The fingerprint sensor of the OLED display in the related art is located above the OLED back plate, so it has high transmittance, and accordingly, the stray light in the external environment that enters the fingerprint sensor is greatly increased. Generally, the illuminance of the RGB signal light after reaching the fingerprint sensor is 10 -1 lx, but stray light in the external environment is stronger than RGB signal light, reaching a maximum of 100,000 lx. Even if stray light passes through a finger and reaches the fingerprint sensor, it is only 10 1 ~10 2 lx, which makes the signal light difficult to identify by the fingerprint sensor.

[0030] After investigation, it was found that stray light in the environment has two effects on sensor performance. When stray light is irradiated onto a fingerprint sensor, it can saturate the fingerprint sensor's photodiode PIN, and even if it is not saturating, it can significantly reduce the contrast between the ridges and valleys of the fingerprint. On the other hand, the thin film transistors (TFTs) of some OLED displays use the low temperature polysilicon (LTPS) process, and the leakage current (Ioff) of LTPS TFTs increases significantly when exposed to strong light, resulting in a decrease in the signal level of the fingerprint sensor and an increase in noise.

[0031] The present invention has been made in view of the above-mentioned problems, and embodiments of the present disclosure provide a display panel and a display device that can improve the adverse effects of stray light in the environment on the photosensitive elements in the display panel.

[0032] 1 to 10 are schematic cross-sectional views of several embodiments of display panels of the present disclosure.

[0033] 1 to 10, in some embodiments, a display panel includes a substrate 1, a driving circuit layer 2, a plurality of light-emitting elements 5, a photosensitive element 6, and a light-shielding element. The substrate may be made of glass or ceramic. The driving circuit layer 2 is used to provide driving currents to devices in the display panel to realize device control functions. In FIG. 1, the driving circuit includes a plurality of first TFTs 26 and a second TFT 27 formed on the substrate 1. The second TFT 27 is disposed between adjacent first TFTs 26 among the plurality of first TFTs 26.

[0034] 1 to 4 and 8 to 10, the first TFT 26 includes an active layer 26a, a first gate layer 26b, a second gate layer 26c, a first source / drain layer 26d, and a second source / drain layer 26e. The first source / drain layer 26d is used to form the source and drain of the first TFT 26. The second source / drain layer 26e is electrically connected to the first source / drain layer 26d.

[0035] In some embodiments, the drive circuit layer 2 further includes a first gate insulating layer 21, a second gate insulating layer 22, an interlayer insulating layer 23, a first passivation layer 24, and a second passivation layer 25. Along a direction away from the substrate (i.e., the vertical direction from bottom to top shown in FIG. 1 ), an active layer 26a is disposed on the substrate 1, and a first gate insulating layer 21 is also disposed on the substrate 1 and covers the active layer 26a. A first gate layer 26b is disposed on the first gate insulating layer 21, and a second gate insulating layer 22 is disposed on the first gate insulating layer 21 and covers the first gate layer 26b. A second gate layer 26c is disposed on the second gate insulating layer 22, and an interlayer insulating layer 23 is disposed on the second gate insulating layer 22 and covers the second gate layer 26b. A first source / drain layer 26d is disposed on the interlayer insulating layer 23 and is electrically connected to the first active layer 26a through a via hole. The first passivation layer 24 is provided on the interlayer insulating layer 23 and covers the first source / drain layer 26d. The second source / drain layer 26e is provided on the first passivation layer 24 and is electrically connected to the first source / drain layer 26d through a via hole.

[0036] 1 to 4 and 8 to 10, the second TFT 27 includes an active layer 27a, a first gate layer 27b, a first source / drain layer 27d, and a second source / drain layer 27e. The first source / drain layer 27d is used to form the source and drain of the second TFT 27. The second source / drain layer 27e is electrically connected to the first source / drain layer 27d.

[0037] 1, an active layer 27a is disposed on the substrate 1, and a first gate insulating layer 21 is also disposed on the substrate 1 and covers the active layer 27a. A third gate layer 27b is disposed on the first gate insulating layer 21, and a second gate insulating layer 22 is disposed on the first gate insulating layer 21 and covers the first gate layer 27b. A first source / drain layer 27d is disposed on the interlayer insulating layer 23 and is electrically connected to the active layer 27a through a via hole. A first passivation layer 24 is disposed on the interlayer insulating layer 23 and covers the first source / drain layer 27d. A second source / drain layer 27e is disposed on the first passivation layer 24 and is electrically connected to the first source / drain layer 27d through a via hole.

[0038] 5 to 7, in another embodiment, the first TFT 26 or the second TFT 27 may include one or more gate layers and corresponding gate insulating layers. Referring to FIGS. 1 to 10, in some embodiments, a plurality of light-emitting elements 5 are disposed on the side of the driving circuit layer 2 away from the substrate 1 and are electrically connected to the plurality of first thin film transistors, respectively.

[0039] In some embodiments, at least one of the plurality of light-emitting elements 5 is an OLED. The OLED includes an anode layer 51, an organic light-emitting layer 52, and a cathode layer 53. In FIGS. 1 to 7, the display panel further includes a planarization layer 3 disposed between the drive circuit layer 2 and the plurality of light-emitting elements 5. The anode layer 51 is disposed on a side of the planarization layer 3 away from the drive circuit layer 2, and is electrically connected to a first electrode of a first TFT 26 (e.g., a second source / drain layer 26e of the first TFT 26) through a via hole in the planarization layer 3.

[0040] The organic light-emitting layer 52 is provided on the side of the anode layer 51 away from the drive circuit layer 2, and the cathode layer 53 is provided on the side of the organic light-emitting layer 52 away from the drive circuit layer 2. The organic light-emitting layer 52 may include a light-emitting functional layer such as an electron injection layer, an electron blocking layer, an electron transport layer, an light-emitting layer, a hole injection layer, a hole blocking layer, or a hole transport layer. In another embodiment, the light-emitting element 5 may be a light-emitting diode (LED), a quantum dot light-emitting diode (QLED), or the like.

[0041] The plurality of light-emitting elements 5 are electrically connected to the corresponding plurality of first TFTs 26 through via holes. For example, each light-emitting element 5 corresponds to one first TFT 26 in the driving circuit layer 2, and correspondingly, the planarization layer 3 arranged below each light-emitting element 5 is provided with a via hole for realizing electrical connection between the light-emitting element 5 and the first electrode of the corresponding first TFT 26.

[0042] In some embodiments, the photosensitive element 6 is used to realize fingerprint detection in the display panel and is used as a fingerprint sensor, while in other embodiments the photosensitive element 6 can also be used in other aspects, such as gesture recognition.

[0043] 1 to 10 , in some embodiments, a photosensitive element 6 is disposed between adjacent light-emitting elements 5 of the plurality of light-emitting elements 5 in the planarization layer and is electrically connected to the second TFT 27. Along the vertical direction from bottom to top shown in FIG. 1 , the photosensitive element 6 may include an N-type amorphous silicon layer 61, an amorphous silicon layer 62, and a P-type amorphous silicon layer 63, which are stacked in sequence. In FIGS. 1 to 10 , the photosensitive element 6 may include an indium tin oxide (ITO) anode conductive layer 64 and a top electrode layer 65. The N-type amorphous silicon layer 61 contacts and is electrically connected to a second electrode of the second TFT 27 (e.g., a second source / drain layer 27e of the second TFT 27). In other embodiments, the photosensitive element 6 may have other structures, such as providing a silicon dioxide layer between the N-type amorphous silicon layer 61 and the P-type amorphous silicon layer 63, or replacing the ITO anode conductive layer with an IZO or AZO anode conductive layer.

[0044] 1 to 10, the second passivation layer 25 covers the first passivation layer 24, the second source / drain layer 26e, the fourth source / drain layer 27e, and the upper electrode layer 65 of the photosensitive element 6 and below. The planarization layer 3 is disposed on the side of the drive circuit layer 2 away from the substrate 1. In FIG. 1, the planarization layer 3 covers the surface of the second passivation layer 25 away from the drive circuit layer 2, thereby forming a flat surface for disposing the anode layer 51 of the light-emitting element 5 and the upper electrode layer 65 of the photosensitive element 6.

[0045] 1 to 10 , in some embodiments, the display panel further includes a pixel definition layer 4. The pixel definition layer 4 is disposed on a side of the planarization layer 3 away from the drive circuit layer 2 and has a plurality of openings 41. The pixel definition layer 4 divides a light-emitting region and a non-light-emitting region by the plurality of openings 41. The anode layer 51 of the light-emitting element 5 is disposed between the pixel definition layer 4 and the planarization layer 3 and has a portion exposed to at least one of the plurality of openings 41. The organic light-emitting layer 52 is disposed in at least one of the plurality of openings 41 and covers the surface of the exposed portion of the anode layer 51. The cathode layer 53 covers the surfaces of the pixel definition layer 4 and the organic light-emitting layer 52.

[0046] 1 to 10, the pixel definition layer 4 may be provided with a support 72 for mask processing and a thin-film packaging layer 71 for packaging. A polarizing plate, a cover plate, or the like may be adhered to the side of the thin-film packaging layer 71 away from the substrate 1 using an optically transparent adhesive.

[0047] Stray light from the environment other than the display panel enters the photosensitive element 6 via two optical paths. One is ambient light a (the optical path of which is shown by a dashed line with an arrow) that travels from above the display panel in FIG. 1 through gaps between the devices of the display panel to reach the lower TFT channel of the second TFT 27 connected to the photosensitive element 6. The other is ambient light b (the optical path of which is shown by a dotted line with an arrow) that is irradiated directly onto the ITO anode conductive layer 64 of the photosensitive element 6 from above the display panel.

[0048] In some embodiments, the second TFT 27 has a top-gate structure, i.e., the first gate layer 27b is disposed above the TFT channel, making it difficult for the ambient light a to directly illuminate the TFT channel from above. On the other hand, for a medium capable of transmitting light, such as a glass substrate 1, the ambient light a can enter the substrate 1 and then be reflected by the bottom surface of the substrate 1 to enter the TFT channel.

[0049] To address the adverse effects of ambient light a on the photosensitive elements 6, in some embodiments, the display panel further includes a light-blocking element. The light-blocking element is disposed in the optical path of ambient light from outside the display panel propagating to the TFT channel of the second TFT 27 within the display panel, thereby reducing the amount of ambient light propagating to the TFT channel of the second TFT 27. In this way, defects such as saturation or increased leakage current of the photosensitive elements 6 due to ambient light can be effectively reduced or eliminated, thereby improving the sensitivity of the photosensitive elements 6.

[0050] Referring to FIG. 1 , in some embodiments, the light-shielding element includes a first light-shielding layer 91. The first light-shielding layer 91 is made of a light-absorbing material (e.g., a black photoresist material). The first light-shielding layer 91 is disposed between the driving circuit layer 2 and the plurality of light-emitting elements 5 and is used to block ambient light from entering the driving circuit layer 2. In this embodiment, the first light-shielding layer 91 is the planarization layer 3. In this manner, when ambient light is irradiated onto the planarization layer 3, it is absorbed by the light-absorbing material of the planarization layer 3, thereby preventing or reducing the ambient light from passing through the planarization layer 3 and entering the driving circuit layer 2. As a result, the ambient light entering the TFT channel of the second TFT 27 can be reduced.

[0051] 1, the photosensitive element 6 is provided in a first light-shielding layer 91. In order to prevent the light-absorbing material of the first light-shielding layer from affecting the normal photosensitivity of the photosensitive element 6, referring to FIG. 1, in some embodiments, the photosensitive element 6 is exposed on the side of the first light-shielding layer 91 away from the driving circuit layer 2 so that the first light-shielding layer 91 does not shield the ITO anode conductive layer 64 of the photosensitive element 6. In another embodiment, the photosensitive element 6 is not exposed from the first light-shielding layer 91 on the side of the first light-shielding layer 91 away from the driving circuit layer 2 so as to ensure light transmittance.

[0052] 2, 4, 6, and 7, in some embodiments, the second electrode of the second TFT 27 (e.g., the second source / drain layer 27e of the second TFT 27) is disposed in the same layer as the first electrode of the first TFT 26 (e.g., the second source / drain layer 26e of the first TFT 26). The light-blocking element includes an extension 92 of the second electrode of the second TFT 27 that extends toward the first electrode of the first TFT 26. The orthogonal projection of the extension 92 onto the substrate 1 at least partially overlaps with the orthogonal projection of the anode layer 51 onto the substrate 1. In FIG. 2, a double arrow indicates a portion c where the extension 92 of the second source / drain layer 27e and the anode layer 51 overlap in the projection. In other words, by increasing the area of ​​the second electrode of the second TFT, the second electrode partially overlaps with the anode layer of the light-emitting element in projection, thereby reducing the aperture ratio of the display panel and reducing ambient light entering through the device gaps of the display panel.

[0053] In order to make the anode layer of the light-emitting device smoother during processing, in some embodiments, the orthogonal projection of the photosensitive element 6 onto the substrate 1 does not overlap with the orthogonal projection of the anode layer 51 onto the substrate 1. In FIG. 2, the extended portion of the second source / drain layer 27e is directly below the anode layer 51, and the photosensitive element 6 is not directly below the anode layer 51.

[0054] 3 to 5 and 7, in some embodiments, the substrate 1 is a glass substrate, and the light-blocking element includes a light-absorbing layer 93. The light-absorbing layer 93 is disposed on the surface of the glass substrate away from the planarization layer 3 (i.e., the lower surface of the glass substrate in FIG. 2). In this manner, when stray light from the environment other than the display panel enters the interior of the display panel and reaches the lower surface of the substrate 1, the ambient light is absorbed by the light-absorbing layer 93, thereby minimizing the amount of ambient light reflected onto the TFT channel of the second TFT 27 and reducing the reflectance of the substrate 1. The light-absorbing layer 93 can be made of a black material with high light absorption, such as a black matrix (BM), a copper film with a graphite layer, or another film material with a graphite layer.

[0055] In FIG. 4, the extension portion 92 of the second electrode of the second TFT 27 can effectively block a portion of the ambient light incident through the device gap of the display panel, and by providing a light absorption layer 93 on the surface of the glass substrate away from the planarization layer 3, the possibility of light reflected between the second electrode and the anode layer 51 entering the TFT channel of the second TFT 27 can be further reduced.

[0056] 5 to 7 , in some embodiments, to further reduce the amount of ambient light reflected and reaching the TFT channel of the second TFT 27, the second TFT 27 includes an active layer 27a and a first gate layer 27b. The active layer 27a is disposed on a side of the substrate 1 closer to the photosensitive element 6. The first gate layer 27b is disposed on a side of the active layer 27a farther from the substrate 1. The light-blocking element may include a second gate layer 94. The second gate layer 94 is disposed between the substrate 1 and the active layer 27a. The first gate layer 27b is electrically connected to the second gate layer 94 through a via hole. At least a portion of the orthogonal projection of the second gate layer 94 onto the substrate 1 overlaps with the orthogonal projection of the first gate layer 27b onto the substrate 1. As a result, the second gate layer 94 blocks the ambient light reflected by the substrate from entering the TFT channel of the second TFT 27.

[0057] 6, in another embodiment, when the second TFT 27 adopts a dual gate structure, the light absorption layer 93 does not need to be provided on the surface of the substrate away from the planarization layer 3. Note that in FIGS. 5 to 7, the first TFT 26 further includes a third gate layer 26f, and the third gate layer 26f and the second gate layer 94 can be formed by the same deposition process. The third gate layer 26f is disposed between the first active layer 26a and the substrate 1, and is electrically connected to the first gate layer 26b through a via hole.

[0058] In the embodiment shown in FIG. 7, the light-blocking element may include the aforementioned extension 92 of the second TFT 27, the light-absorbing layer 93, and the second gate layer 94, and this triple blocking measure can prevent ambient light a from reaching the TFT channel of the second TFT 27 as much as possible.

[0059] 3 to 5 , with respect to ambient light b irradiating directly onto the ITO anode conductive layer 64 of the photosensitive element 6 from above the panel, in some embodiments, the display panel further includes a filter layer 8 disposed on the side of the photosensitive element 6 away from the driving circuit layer 2. In FIGS. 3 to 5 , the filter layer 8 is disposed within the pixel definition layer 4 and covers the side of the photosensitive element 6 away from the driving circuit layer 2. The material of the filter layer 8 is a filter material, such as a color photoresist material commonly used in liquid crystal display devices. The filter material blocks light with wavelengths higher than a specified wavelength and transmits light with wavelengths equal to or lower than a specified wavelength. Such a filter layer 8 can be formed by coating it over the photosensitive element. By forming the filter layer 8 and then fabricating the conventional pixel definition layer 4, the manufacturing process is simplified and the material requirements and process difficulties are reduced.

[0060] 6, in addition to employing a filter layer 8, in some embodiments, at least one of the planarization layer 3′ and the pixel definition layer 4′ can employ a filter material configured to block light with wavelengths above a set wavelength and transmit light with wavelengths below a set wavelength.

[0061] In the embodiments of Figures 3, 5, and 8 to 10, when the photosensitive element is used for fingerprint authentication, the photosensitive element used for fingerprint authentication is located under the finger during use, and ambient light with a wavelength exceeding 600 nm can usually pass through the finger. Therefore, in some embodiments, a filter material with a set wavelength of 550 nm to 620 nm (600 nm is more preferable) is used to block light with a wavelength higher than the set wavelength and transmit light with a wavelength equal to or lower than the set wavelength. As a result, in the case of fingerprint authentication, the ambient light that has passed through the finger cannot further pass through the photosensitive surface of the photosensitive element, reducing the adverse effects of ambient light on the photosensitive element.

[0062] 10 , in some embodiments, the light-shielding element includes a second light-shielding layer 95, which is disposed on the side of the driving circuit layer 2 away from the substrate 1 as the pixel definition layer 4 and is used to block ambient light from entering the driving circuit layer 2, thereby reducing or preventing the ambient light a from irradiating the TFT channel of the second TFT 27 connected to the photosensitive element 6. A light-absorbing material (e.g., a black photoresist material) is adopted as the material of the second light-shielding layer 95.

[0063] 10, the filter layer 8 is disposed within the second light-shielding layer 95. In order to reduce the ambient light b directly irradiating the photosensitive element 6, the filter layer 8 covers the side of the photosensitive element 6 away from the substrate 1, and is exposed on the side of the second light-shielding layer 95 away from the drive circuit layer 2 so as not to shield the filter layer 8. In another embodiment, the filter layer 8 is not exposed on the side of the second light-shielding layer 95 away from the drive circuit layer 2, and the light-absorbing material disposed above the filter layer 8 is very thin (e.g., less than 2000 Å thick) to ensure light transmittance.

[0064] Based on the above-mentioned embodiments of the display panel, the present disclosure further provides a display device including any of the above-mentioned embodiments of the display panel, which may be any product or component with a display function, such as a mobile phone, a tablet computer, a television, a monitor, a laptop, a digital photo frame, or a navigation system.

[0065] Up to now, each embodiment of the present disclosure has been described in detail. In order to avoid obscuring the concept of the present disclosure, some details known in the art will not be described. Those skilled in the art can fully understand how the technical solutions disclosed in this specification are realized from the above description.

[0066] Although some specific embodiments of the present disclosure have been described in detail by way of examples, those skilled in the art should understand that the above examples are merely for illustrative purposes and are not intended to limit the scope of the present disclosure. Those skilled in the art should understand that the above embodiments may be modified or some of the technical features may be substituted with equivalents without departing from the scope and spirit of the present disclosure. The scope of the present disclosure is limited by the appended claims. [Explanation of symbols]

[0067] 1 board 2. Drive circuit layer 3 Planarization layer 4 Pixel Definition Layer 5 Light-emitting element 6 Photosensitive element 21 First gate insulating layer 22 Second gate insulating layer 23 Interlayer insulating layer 24 1st passive layer 25 Second passive layer 26 1st TFT 26a Active layer 26b First gate layer 26c Second gate layer 26d First source / drain layer 26e Second source / drain layer 27 2nd TFT 27a Active layer 27b First gate layer 27d First source / drain layer 27e Second source / drain layer 51 Anode layer 52 Organic light-emitting layer 53 Cathode layer 61 N-type amorphous silicon layer 62 amorphous silicon layer 63 P-type amorphous silicon layer 64 Indium Tin Oxide (ITO) Anode Conductive Layer 65 Upper electrode layer 71 Thin Film Package Layer 91 1st light shielding layer

Claims

1. A display panel, a substrate, a driving circuit layer, a plurality of light-emitting elements, a photosensitive element, a light-shielding element, and a filter layer; Including, the driving circuit layer includes a plurality of first thin film transistors and a plurality of second thin film transistors disposed on the substrate, the second thin film transistors being disposed between adjacent first thin film transistors among the plurality of first thin film transistors; the plurality of light-emitting elements are disposed on a side of the driving circuit layer away from the substrate, and are electrically connected to the plurality of first thin film transistors, respectively; the photosensitive element is disposed between adjacent light-emitting elements among the plurality of light-emitting elements and is electrically connected to the second thin film transistor; the light-blocking element is disposed in an optical path along which ambient light from outside the display panel propagates to the thin film transistor channel of the second thin film transistor within the display panel, thereby reducing the ambient light propagating to the thin film transistor channel of the second thin film transistor; at least one of the plurality of light-emitting elements is an organic light-emitting diode, the organic light-emitting diode including an anode layer electrically connected to a first electrode of the first thin film transistor and an organic light-emitting layer located on a side of the anode layer away from the substrate, a second electrode of the second thin film transistor being disposed in the same layer as a first electrode of the first thin film transistor, and the light-blocking element including an extending portion of the second electrode extending toward the first electrode, a distance between an orthogonal projection of the first gate layer of the second thin film transistor onto the substrate and an orthogonal projection of the organic light-emitting layer onto the substrate is smaller than a distance between an orthogonal projection of the photosensitive element onto the substrate and an orthogonal projection of the organic light-emitting layer onto the substrate, so as to prevent ambient light from outside the display panel from reaching a thin film transistor channel of the second thin film transistor, and an orthogonal projection of the extended portion onto the substrate at least partially overlaps with an orthogonal projection of the anode layer onto the substrate; Display panel.

2. 2. The display panel of claim 1, wherein an orthogonal projection of the photosensitive element onto the substrate does not overlap with an orthogonal projection of the anode layer onto the substrate.

3. 2. The display panel of claim 1, further comprising a planarization layer disposed between the driving circuit layer and the plurality of light-emitting elements, the photosensitive element being disposed within the planarization layer, and an anode layer of the organic light-emitting diode being disposed on a side of the planarization layer away from the driving circuit layer and electrically connected to a first electrode of the first thin film transistor through a via hole in the planarization layer.

4. 4. The display panel according to claim 1, wherein the substrate is a glass substrate, and the light-blocking element includes a light-absorbing layer disposed on a surface of the glass substrate away from the drive circuit layer.

5. The second thin film transistor is further comprising an active layer disposed on a side of the substrate closer to the photosensitive element; the first gate layer is disposed on a side of the active layer away from the substrate; the light-blocking element includes a second gate layer disposed between the substrate and the active layer, and at least a portion of an orthogonal projection onto the substrate overlaps with an orthogonal projection of the first gate layer onto the substrate; The display panel according to claim 1 .

6. 2. The display panel of claim 1, wherein the light-shielding elements include a first light-shielding layer, the first light-shielding layer being disposed between the driving circuit layer and the plurality of light-emitting elements as a planarization layer and being used to block ambient light from entering the driving circuit layer.

7. The display panel according to claim 6 , wherein the light-sensitive elements are disposed in the first light-shielding layer and are exposed on a side of the first light-shielding layer away from the drive circuit layer.

8. a planarization layer disposed between the driving circuit layer and the plurality of light-emitting elements; a pixel definition layer disposed on a side of the planarization layer remote from the drive circuit layer; further comprising a material of at least one of the planarization layer and the pixel definition layer is a filter material, the filter material being configured to block light having a wavelength higher than a set wavelength and transmit light having a wavelength equal to or lower than a set wavelength; The display panel according to claim 1 .

9. the filter layer is disposed on a side of the photosensitive element away from the drive circuit layer, the material of the filter layer is a filter material, the filter material is configured to block light of a wavelength higher than a set wavelength and transmit light of a wavelength equal to or lower than the set wavelength, and at least a part of an orthogonal projection of the filter layer onto the substrate overlaps with an orthogonal projection of the photosensitive element onto the substrate. The display panel according to claim 1 .

10. the light-shielding element includes a second light-shielding layer, the second light-shielding layer being disposed as a pixel definition layer on a side of the driving circuit layer away from the substrate, and the filter layer being provided in the second light-shielding layer and exposed on a side of the second light-shielding layer away from the driving circuit layer; The display panel according to claim 9 .

11. 11. The display panel according to claim 8, wherein the set wavelength is 550 nm to 620 nm.

12. The display panel of claim 11 , wherein the set wavelength is 600 nm.

13. at least one of the plurality of light-emitting elements is an organic light-emitting diode; The organic light-emitting diode an anode layer disposed between the pixel definition layer and the planarization layer, the anode layer having a portion exposed to at least one of the plurality of openings in the pixel definition layer; an organic light-emitting layer disposed in at least one of the plurality of openings and covering a surface of the exposed portion of the anode layer; a cathode layer covering the pixel definition layer and the organic light-emitting layer; Including, The display panel according to claim 8 .

14. 14. The display panel of claim 1, wherein the photosensitive element includes an N-type amorphous silicon layer, an amorphous silicon layer, and a P-type amorphous silicon layer stacked in sequence along a direction away from the drive circuit layer.

15. The display panel according to claim 1 , wherein the photosensitive element is used for fingerprint authentication.

16. A display device comprising the display panel according to any one of claims 1 to 15.

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