CN112993184A

CN112993184A - Display substrate and display device

Info

Publication number: CN112993184A
Application number: CN202110166665.XA
Authority: CN
Inventors: 任怀森; 侯鹏; 夏维; 李�杰
Original assignee: BOE Technology Group Co Ltd; Chengdu BOE Optoelectronics Technology Co Ltd
Current assignee: BOE Technology Group Co Ltd; Chengdu BOE Optoelectronics Technology Co Ltd
Priority date: 2021-02-04
Filing date: 2021-02-04
Publication date: 2021-06-18
Anticipated expiration: 2041-02-04
Also published as: CN112993184B

Abstract

A display substrate comprises a base, a photosensitive device and a light-emitting device, wherein the photosensitive device and the light-emitting device are arranged on the base, the display substrate further comprises a reflecting structure and a light shielding structure which correspond to the photosensitive device, the reflecting structure is configured to reflect light rays incident from the reflecting structure far away from the base side, and at least part of the reflected light rays face the corresponding photosensitive device; the light shielding structure is arranged on one side, far away from the substrate, of the photosensitive device, and on a plane parallel to the substrate, the orthographic projection of the photosensitive device is at least partially located in the orthographic projection of the light shielding structure. According to the scheme provided by the embodiment, the light is shielded by the light shielding structure, and the reflection structure enables the reflected light to enter the photosensitive device, so that the signal to noise ratio can be improved.

Description

Display substrate and display device

Technical Field

Embodiments of the present disclosure relate to, but not limited to, display technologies, and more particularly, to a display substrate and a display device.

Background

Not only application fields of the organic light emitting display device are diversified, but also some products are gradually developed to be multifunctional, such as optical in-screen fingerprints. At present, the fingerprint identification technology mainly comprises a capacitance type, an optical type and an ultrasonic type. The capacitance can only be integrated on a Cover plate (Cover) due to the limitation of the penetration distance and cannot be used under a screen; ultrasonic type is not easy to integrate into the screen due to material limitation. The screen only conforms to the optical type and the ultrasonic type of the full screen, and not only conforms to the full screen and the large screen, but also can be integrated, and the optical type is preferred.

Disclosure of Invention

The following is a summary of the subject matter described in detail herein. This summary is not intended to limit the scope of the claims.

The embodiment of the application provides a display substrate and a display device, and improves fingerprint identification signal-to-noise ratio

In one aspect, embodiments of the present application provide a display substrate, which includes a substrate, a photosensitive device and a light emitting device disposed on the substrate, and further includes a reflective structure and a light blocking structure corresponding to the photosensitive device, where the reflective structure is configured to reflect light incident from the reflective structure away from the substrate side, and the reflected light is at least partially directed toward the corresponding photosensitive device; the light shielding structure is arranged on one side, far away from the substrate, of the photosensitive device, and on a plane parallel to the substrate, the orthographic projection of the photosensitive device is at least partially located in the orthographic projection of the light shielding structure.

In an exemplary embodiment, the reflective structure includes a reflective layer, the photosensitive device is disposed between the substrate and the light emitting device, and the reflective layer is disposed between the photosensitive device and the substrate.

In an exemplary embodiment, the display substrate further includes a thin film transistor disposed between the base and the light emitting device, the thin film transistor including an active layer, a gate electrode, a source electrode, and a drain electrode sequentially disposed on the base, and the reflective layer is disposed at the same layer as the gate electrode.

In an exemplary embodiment, the display substrate further includes a thin film transistor disposed between the base and the light emitting device, and a light shielding layer disposed on a side of the thin film transistor close to the base, and the reflective layer and the light shielding layer are disposed in the same layer.

In an exemplary embodiment, the light shielding structure includes a light shielding layer, the light shielding layer is provided with a light transmitting portion corresponding to the photosensitive device, an orthographic projection of the photosensitive device is located inside an orthographic projection of the light shielding layer, and the orthographic projection of the light transmitting portion is located outside the orthographic projection of the photosensitive device on a plane parallel to the substrate.

In an exemplary embodiment, the light emitting device includes a first electrode, a light emitting layer, and a second electrode sequentially disposed, the first electrode is disposed on a side of the light emitting layer close to the substrate, and the first electrode is multiplexed as the light shielding layer.

In an exemplary embodiment, the display substrate further includes an encapsulation layer disposed on a side of the light emitting device away from the base, the reflective structure is disposed on a side of the encapsulation layer away from the base, the reflective structure includes a first reflective layer and a second reflective layer disposed in sequence, the first reflective layer is located on a side of the second reflective layer close to the base, the light emitting device includes a light emitting layer, an orthographic projection of the first reflective layer overlaps with an orthographic projection of the second reflective layer on a plane parallel to the base, the orthographic projection of the first reflective layer is located outside the orthographic projection of the second reflective layer, and the orthographic projection of the first reflective layer and the orthographic projection of the second reflective layer are located outside the orthographic projection of the light emitting layer.

In an exemplary embodiment, the second reflective layer is multiplexed as the light shielding structure.

In an exemplary embodiment, an orthographic projection of the first reflective layer on a plane parallel to the substrate is annular, and the orthographic projection of the first reflective layer surrounds the orthographic projection of the photosensitive device.

In an exemplary embodiment, the display substrate further includes a first touch electrode layer and a second touch electrode layer sequentially disposed on a side of the encapsulation layer away from the substrate, the first reflective layer and the first touch electrode layer are disposed on the same layer, and the second reflective layer and the second touch electrode layer are disposed on the same layer.

In an exemplary embodiment, the light emitting device further includes a first electrode and a second electrode respectively disposed on two sides of the light emitting layer, the first electrode is disposed on one side of the light emitting layer close to the substrate, the photosensitive device and the light emitting device are disposed in the same layer, a pixel defining layer is disposed between the first electrode and the light emitting layer, and the pixel defining layer is made of an opaque material.

In an exemplary embodiment, the display substrate further includes: and the condenser is arranged on one side of the reflecting structure, which is far away from the substrate, and at least part of light rays condensed by the condenser are incident to the reflecting structure.

In another aspect, an embodiment of the present disclosure provides a display device, including the display substrate.

The embodiment of the application comprises a display substrate and a display device, wherein the display substrate comprises a base, a photosensitive device and a light-emitting device which are arranged on the base, and the display substrate further comprises a reflecting structure and a shading structure which correspond to the photosensitive device, the reflecting structure is configured to reflect light rays incident from the reflecting structure far away from the base side, and at least part of the reflected light rays face the corresponding photosensitive device; the light shielding structure is arranged on one side, far away from the substrate, of the photosensitive device, and on a plane parallel to the substrate, the orthographic projection of the photosensitive device is at least partially located in the orthographic projection of the light shielding structure. According to the scheme provided by the embodiment, the light is shielded by the light shielding structure, and the reflection structure enables the reflected light to enter the photosensitive device, so that the signal to noise ratio can be improved.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the written description and drawings.

Other aspects will be apparent upon reading and understanding the attached drawings and detailed description.

Drawings

The accompanying drawings are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the example serve to explain the principles of the invention and not to limit the invention.

FIG. 1 is a schematic diagram of a display substrate according to an exemplary embodiment (a reflective layer and a gate metal layer are disposed on the same layer);

FIG. 2 is a schematic plan view of a display substrate provided in accordance with an exemplary embodiment;

FIG. 3 is a schematic illustration of a display substrate provided in an exemplary embodiment (anode expanded);

FIG. 4 is a schematic diagram of a display substrate (with a light concentrator) provided in accordance with an exemplary embodiment;

FIG. 5 is a schematic diagram of a display substrate according to an exemplary embodiment (a reflective layer and a light shielding layer are disposed on the same layer);

FIG. 6 is a schematic diagram of a display substrate provided in an exemplary embodiment (with a photosensitive device disposed on a substrate surface);

FIG. 7 is a schematic illustration of a display substrate provided in an exemplary embodiment (anode expanded);

FIG. 8 is a schematic illustration of a display substrate provided in an exemplary embodiment (anode expanded);

FIG. 9 is a schematic diagram of a display substrate provided in an exemplary embodiment (with a reflective layer and a light shielding layer on the same layer);

FIG. 10 is a schematic diagram of a display substrate according to an exemplary embodiment (with a reflective structure on a touch layer);

FIG. 11 is a schematic plan view of a first reflective layer and a photosensitive device provided in accordance with an exemplary embodiment;

FIG. 12 is a schematic diagram of a display substrate provided in accordance with an exemplary embodiment;

FIG. 13 is a schematic diagram of a display substrate (with a light concentrator) according to an exemplary embodiment.

Detailed Description

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the present application, the embodiments and features of the embodiments may be arbitrarily combined with each other without conflict.

The steps illustrated in the flow charts of the figures may be performed in a computer system such as a set of computer-executable instructions. Also, while a logical order is shown in the flow diagrams, in some cases, the steps shown or described may be performed in an order different than here.

Unless defined otherwise, technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which this invention belongs.

In the drawings, the size of each component, the thickness of layers, or regions may be exaggerated for clarity. Therefore, the embodiments of the present disclosure are not necessarily limited to the dimensions, and the shapes and sizes of the respective components in the drawings do not reflect a true scale. Further, the drawings schematically show ideal examples, and the embodiments of the present disclosure are not limited to the shapes or numerical values shown in the drawings.

The ordinal numbers such as "first", "second", "third", etc., in this disclosure are provided to avoid confusion among the constituent elements, and do not indicate any order, number, or importance.

In the present disclosure, for convenience, terms indicating orientation or positional relationship such as "middle", "upper", "lower", "front", "rear", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like are used to explain positional relationship of constituent elements with reference to the drawings, only for convenience of description and simplification of description, and do not indicate or imply that the device or element referred to must have a specific orientation, be configured in a specific orientation, and be operated, and thus, should not be construed as limiting the present disclosure. The positional relationship of the components is changed as appropriate in accordance with the direction in which each component is described. Therefore, the words described in the disclosure are not limited thereto, and may be replaced as appropriate.

In this disclosure, the terms "mounted," "connected," and "connected" are to be construed broadly unless otherwise specifically stated or limited. For example, it may be a fixed connection, or a removable connection, or an integral connection; can be a mechanical connection, or an electrical connection; either directly or indirectly through intervening components, or both may be interconnected. The specific meaning of the above terms in the present disclosure can be understood in specific instances by those of ordinary skill in the art.

In the present disclosure, a transistor refers to an element including at least three terminals of a gate electrode, a drain electrode, and a source electrode. The transistor has a channel region between a drain electrode (drain electrode terminal, drain region, or drain electrode) and a source electrode (source electrode terminal, source region, or source electrode), and current can flow through the drain electrode, the channel region, and the source electrode. In the present disclosure, the channel region refers to a region through which current mainly flows. In the present disclosure, "source electrode" and "drain electrode" may be interchanged with each other.

In the present disclosure, "film" and "layer" may be interchanged with one another. For example, the "conductive layer" may be sometimes replaced with a "conductive film". Similarly, the "insulating film" may be replaced with an "insulating layer".

In a current Organic Light Emitting Diode (OLED) film, the transmittance of an inorganic layer and an Organic layer is substantially greater than 90%, and the reflectance after the aluminum (Al) metal Pattern (Pattern) is tested is substantially greater than 80%. Therefore, fingerprint recognition can be achieved by light reflection.

In the optical method, the photosensitive device receives signal light to realize photoelectric conversion, so that the function of optical fingerprint identification is realized. However, the photosensor receives noise light (i.e., light other than the signal light) outside the panel in addition to the signal light, and therefore it is necessary to increase the ratio of the signal light to the noise light to improve the signal-to-noise ratio. In the embodiment of the disclosure, the reflective layer pattern and the light shielding layer pattern are prepared by using a Back Plate (BP) process segment or a metal film layer of a Flexible Multi-layer on cell (FMLOC) process segment, so as to enhance the signal-to-noise ratio.

The embodiment of the disclosure provides a display substrate, which comprises a substrate, a photosensitive device and a light-emitting device, wherein the photosensitive device and the light-emitting device are arranged on the substrate, and the display substrate further comprises a reflecting structure and a light shielding structure which correspond to the photosensitive device, the reflecting structure is configured to reflect light rays incident from the reflecting structure far away from the substrate side, and at least part of the reflected light rays face the corresponding photosensitive device; the light shielding structure is arranged on one side, far away from the substrate, of the photosensitive device, and on a plane parallel to the substrate, the orthographic projection of the photosensitive device is at least partially located in the orthographic projection of the light shielding structure. The reflective structure may comprise one reflective layer, or alternatively, a plurality of reflective layers. The light shielding structure may use an existing film layer of the display substrate, or a newly added film layer, or one of the plurality of reflective layers.

In an exemplary embodiment, the reflective layer pattern may be prepared using a metal film layer of a BP process, such as a gate metal layer gate or a light blocking Layer (LS), and the photosensitive device may be prepared under the anode and the light Emitting Layer (EL) and on the reflective layer. Light emitted from the light-emitting layer is reflected by the finger to the reflective layer and reflected by the reflective layer to the photosensitive device (i.e., signal light); in addition, the light blocking effect of the anode metal is utilized to prevent the photosensitive device from receiving light directly emitted from the light emitting layer and external ambient light, thereby reducing noise light. The scheme provided by the embodiment can enhance the signal-to-noise ratio.

Fig. 1 is a schematic diagram of a display substrate according to an exemplary embodiment. The display substrate may include a plurality of photosensitive devices and a plurality of reflective layers, only one photosensitive device and one reflective layer being illustrated in fig. 1. As shown in fig. 1, the display substrate may include: a substrate, which may include a first substrate 10a and a second substrate 10b disposed on the first substrate 10 a. The display substrate further comprises an active layer 11 arranged on the substrate, a first insulating layer 12 arranged on one side of the active layer 11 far away from the substrate, a first gate metal layer arranged on one side of the first insulating layer 12 far away from the substrate, wherein the first gate metal layer may comprise a gate electrode 13 and a reflecting layer 14, a second insulating layer 15 arranged on one side of the first gate metal layer far away from the substrate, a third insulating layer 16 arranged on one side of the second insulating layer 15 far away from the substrate, a source drain electrode layer arranged on one side of the third insulating layer 16 far away from the substrate, the source drain electrode layer may comprise a source electrode 17, a drain electrode 18 and a photosensitive device 19, a fourth insulating layer 20 arranged on one side of the source drain electrode layer far away from the substrate, an anode 21 arranged on one side of the fourth insulating layer 20 far away from the substrate, and a pixel defining layer 22 arranged on one side of the anode 21 far away from the substrate, a light emitting layer 23 disposed on a side of the pixel defining layer 22 away from the substrate, an encapsulation layer 24 disposed on a side of the light emitting layer 23 away from the substrate, and a cover plate 25 disposed on a side of the encapsulation layer 24 away from the substrate. A cathode (not shown in fig. 1) is also provided between the light-emitting layer 23 and the encapsulation layer 24.

According to the scheme provided by the embodiment, the signal light emitted by the light emitting layer 23 is reflected to the reflecting layer 14 through the finger 30, the reflecting layer 14 reflects the light to the light incident side of the photosensitive device 19, light path optimization is effectively realized through light reflection, the finger reflected light enters the photosensitive device after being reflected once, light loss is small, and detection sensitivity is high. In addition, in the embodiment, the existing film layer is used for preparing the reflecting layer, a new film layer is not added, the process is simplified, and the cost is reduced.

The principle of fingerprint identification of the display substrate is as follows: when fingerprint identification is performed, a finger 30 of a user presses the cover plate 25, and light emitted from the light-emitting layer 23 irradiates the cover plate 25. Because the valleys of the finger are not actually contacted with the cover plate 25, the critical angles of total reflection of the light at the valleys and the ridges of the fingerprint are different, and the light intensity of the light received by the photosensitive device 19 is different, so that electric signals with different intensities are generated, the valleys and the ridges of the fingerprint can be judged, and the fingerprint pattern is generated.

In the present embodiment, the active layer 11, the gate electrode 13, the source electrode 17, and the drain electrode 18 constitute a thin film transistor, which is electrically connected to the anode 21. In this embodiment, the thin film transistor has a top gate structure, but is not limited thereto, and the thin film transistor may have a bottom gate structure.

In an exemplary embodiment, the substrate is, for example, a flexible substrate, and the first substrate 10a may be made of a flexible material, which may be Polyimide (PI), polyethylene terephthalate (PET), or a surface-treated polymer film. The second substrate 10b is a buffer layer, and may be a single layer or a multilayer structure of silicon nitride/silicon oxide, and may be made of silicon nitride SiNx or silicon oxide SiOx. In other embodiments, the substrate may be other structures, for example, the substrate further includes a third substrate disposed on the second substrate 10b, and the third substrate may be made of a flexible material.

In an exemplary embodiment, the active layer 11 includes a semiconductor. For example, polycrystalline silicon, single crystal silicon, amorphous silicon, or a non-silicon based material such as an oxide semiconductor.

In an exemplary example, the first, second, third, and fourth insulating

layers

12, 15, 16, and 20 may employ silicon oxide (SiOx), silicon nitride (SiNx), silicon oxynitride (SiON), or the like, may have a single-layer structure, or may have a multi-layer composite structure.

In an exemplary embodiment, the gate electrode 13, the source electrode 17, and the drain electrode 18 may be made of a metal material, such as Ag, Cu, Al, Mo, or the like, or an alloy material of the above metals, such as AlNd, MoNb, or the like, and may have a single-layer structure, or may have a multi-layer composite structure, such as Mo/Cu/Mo, or the like.

In an exemplary embodiment, the orthographic projection of said photosensitive device 19 is located within the orthographic projection of said anode 21, in a plane parallel to said substrate. The present embodiment provides a solution that the anode 21 can block external light and light emitted from the light emitting layer, and prevent the external light and light emitted from the light emitting layer from directly entering the photosensor 19, thereby reducing noise light and improving signal-to-noise ratio.

Fig. 2 is a schematic plan view of a light emitting device, a light sensing device, and a reflective layer provided in an exemplary embodiment. The light emitting device 31 may include an anode 21, a cathode, and a light emitting layer 23 between the anode 21 and the cathode. As shown in fig. 2, the display substrate may include a plurality of light emitting devices 31, light sensing devices 19, and a reflective layer 14. The light emitting device 31 may be an organic light emitting diode, or other light emitting device. The light emitting device 31 may include a red light emitting device (R), a green light emitting device (G), and a blue light emitting device (B), or may include a white light emitting device. The orthographic projection of said light-sensitive device 19 is located within the orthographic projection of said light-emitting device 31, for example said light-sensitive device 19 is located within the orthographic projection of anode 21, in a plane parallel to said substrate. On a plane parallel to the substrate, an orthographic projection of the photosensitive device 19 may be located within an orthographic projection of the reflective layer 14, but the embodiment of the present application is not limited thereto, and the orthographic projection of the photosensitive device 19 may be located outside the orthographic projection of the reflective layer 14, or the orthographic projection of the photosensitive device 19 may be partially located within the orthographic projection of the reflective layer 14 and partially located outside the orthographic projection of the reflective layer 14. The cross-sectional shape of the reflective layer 14 and the photosensitive device 19 in a plane parallel to the substrate is not limited and may be square, circular, irregular, and the like.

In an exemplary embodiment, the anode 21 may be an opaque electrode, or a stacked structure of an opaque electrode and a transparent electrode. Examples of the material forming the transparent electrode include Indium Tin Oxide (ITO), Indium Zinc Oxide (IZO), zinc oxide, and indium oxide, and examples of the material forming the opaque electrode include lithium (Li), aluminum (Al), magnesium (Mg), silver (Ag), nickel (Ni), and chromium (Cr).

In an exemplary embodiment, the reflective layer 14 may be an opaque metal such as lithium, aluminum, magnesium, silver, nickel, chromium, molybdenum, copper, titanium, or an alloy of these materials.

In an exemplary embodiment, the photosensitive device 19 may include a photodiode, a photoresistor, a phototransistor, or the like. The photodiode may be a PN-type photodiode, or a PIN-type photodiode, or an Organic Photodiode (OPD).

In an exemplary embodiment, the photosensitive device 19 may include a first pole, a photoelectric conversion layer, and a second pole, which are sequentially disposed; the material of the first pole can be a transparent conductive material, and the first pole is located between the photoelectric conversion layer and the substrate. The material of the first electrode may be a metal Oxide such as zinc Oxide (ZnO), Indium Tin Oxide (ITO), Indium Gallium Zinc Oxide (IGZO), or other transparent conductive material, and is not limited herein. The light reflected by the reflecting layer 14 can enter the photoelectric conversion layer from the first pole. The first pole of the photosensitive device 19 may be provided in the same layer as the source electrode 17 and the drain electrode 18.

In an exemplary embodiment, the photosensitive device 19 may not be disposed on the source-drain electrode layer, and other film layers disposed between the reflective layer 14 and the anode 21, for example, may be disposed between the second insulating layer 15 and the third insulating layer 16. When the photosensitive device 19 is arranged on the source drain electrode layer, the process is simple and easy to realize.

In an exemplary embodiment, a second gate metal layer may be disposed between the first gate metal layer and the photosensitive device 19, the first gate metal layer is provided with a gate electrode and a first capacitor electrode, the second gate metal layer is provided with a second capacitor electrode, and the first capacitor electrode and the second capacitor electrode correspond to each other in position to form a storage capacitor. In this embodiment, the reflective layer 14 may be disposed in the same layer as the second capacitor electrode, that is, in the second gate metal layer. The present embodiment provides a solution that can shorten the distance between the reflective layer 14 and the cover plate 25, that is, shorten the light propagation path, and reduce the light loss.

To further shield noise light (light other than signal light, such as incoming ambient light or light emitted by a light-emitting layer reflected by other film layers than a finger) to enhance signal-to-noise ratio, the anode range may be expanded to leave a hole or slit in the path of the finger-reflected light. As shown in fig. 3, the present embodiment provides a display substrate, in which the structure except the anode can refer to the embodiment shown in fig. 1, in the present embodiment, the area of the anode 21 is enlarged, a hole or a gap is reserved between the adjacent anodes 21 for the finger to reflect light to pass through, and the adjacent anodes 21 are insulated from each other. In the display substrate, holes or gaps may be reserved between the anodes 21 near the photosensitive devices 19, and the distance between the anodes 21 far from the photosensitive devices 19 may be larger. The size of the holes or slits in a plane parallel to the substrate may be set as desired, and by adjusting the size of the light-transmitting holes or slits, the range of incidence angles of the reflected light received by the photosensor 19 can be adjusted. In the solution provided in this embodiment, a hole or a gap is reserved between the anodes 21, so that most of the ambient light is blocked by the anodes 21, and the light reflected by the light emitting device after irradiating the finger enters the reflective layer 14 through the hole or the gap and is reflected by the reflective layer 14 to the photosensitive device 19. The present embodiment provides a solution that reduces the ambient light received by the photosensor 19 and improves the signal-to-noise ratio due to the enlargement of the anode 21.

In the above embodiment, the photosensitive device is shielded using the anode 21 as a light shielding structure. In another embodiment, a light-shielding layer may be provided to shield the photosensitive device. In an exemplary embodiment, the display substrate may include a light-shielding layer disposed on a side of the photosensitive device 19 away from the substrate, the light-shielding layer is provided with a light-transmitting portion corresponding to the photosensitive device 19, and an orthographic projection of the photosensitive device 19 may be located within an orthographic projection of the light-shielding layer on a plane parallel to the substrate, and the orthographic projection of the light-transmitting portion is located outside the orthographic projection of the photosensitive device 19. The light-transmitting portion is located in a propagation path of the finger-reflected light to the reflective layer 14. Light emitted by the light emitting device is reflected by a finger, enters the reflective layer 14 through the light transmitting portion, and is reflected by the reflective layer 14 to the photosensor 19. The light-shielding layer may shield external ambient light from entering the photosensitive device 19, and shield light emitted by the light-emitting device from entering the photosensitive device 19 through the inner film layer from a side of the light-shielding layer away from the substrate. The light-shielding layer may include a plurality of light-shielding portions and a plurality of light-transmitting portions. The light-transmitting portion may be a hole or a slit or may be prepared using a light-transmitting material. The light-transmitting portion may be, for example, a plurality of light-transmitting holes surrounding the photosensor 19, or may be an annular light-transmitting region (which may be a circular ring, a square ring, or the like) surrounding the photosensor 19, or may be a plurality of light-transmitting slits surrounding the photosensor 19, or the like. The light shielding portion may be implemented using an organic material containing a light shielding colorant such as a black pigment or a black dye, or a light shielding metal.

The light-shielding layer may be implemented by multiplexing other functional film layers of the display substrate, or a newly added film layer may be used. In an exemplary embodiment, the light-shielding layer may be implemented as a multiplexed pixel defining layer 22. The pixel defining layer 22 may be prepared using a light shielding material and form a light transmitting portion. When the shading layer is reused with the existing film layer, the structural complexity of the panel can be reduced, the process is simplified, and the cost is reduced.

In an exemplary embodiment, the light shielding layer may be implemented using a fourth insulating layer 20, and the photosensitive device 19 may be disposed on a surface of the second insulating layer 15.

In an exemplary embodiment, in order to better collect the reflected signal light, a condenser may be fabricated at the corresponding film layer. For example, a condenser, such as a lens, is fabricated using the upper Film layer of a Thin Film Encapsulation (TFE) by the FMLOC process.

Fig. 4 is a schematic diagram of a display substrate according to an exemplary embodiment. As shown in fig. 4, the display substrate provided in this embodiment further includes a light collector 40 disposed on a side of the reflective layer 14 away from the base. In this embodiment, the optical concentrator 40 may be disposed on the side of the encapsulation layer 24 away from the substrate, and the cover plate 25 is disposed on the side close to the substrate, but is not limited thereto, and for example, the optical concentrator 40 may be disposed between the third insulation layer 16 and the fourth insulation layer 20. The optical concentrators 40 may correspond one-to-one with the reflective layers 14. The condenser 40 may refract incident light such that the incident light is condensed. The condenser 40 may condense the light emitted from the light emitting layer 23 and reflected by the finger to be incident on the reflective layer 14. The optical concentrator 40 may be bonded between the encapsulation layer 24 and the cover plate 25 using an adhesive. The condenser 40 may be a convex lens, a prism lens, or the like. In this embodiment, the light is condensed by the condenser 40, so that the intensity of the light incident on the photosensor 19 can be enhanced, the sensitivity of fingerprint detection can be improved, and the contrast of a fingerprint image can be improved.

Fig. 5 is a schematic diagram of a display substrate according to an exemplary embodiment. In this embodiment, the display substrate includes a base and a thin film transistor disposed on the base, a Light shielding layer (i.e., a Light Shield layer, an LS layer) is disposed on a side of the thin film transistor close to the base, the Light shielding layer can prevent Light from the base side from irradiating the thin film transistor, and the display substrate further includes a reflective layer disposed on a same layer as the Light shielding layer. As shown in fig. 5, the display substrate includes a substrate, the substrate includes a first substrate 10a and a second substrate 10b, a reflective layer 14 and a light shielding layer (not shown in fig. 5) are disposed between the first substrate 10a and the second substrate 10b, the display substrate further includes an active layer 11 disposed on the second substrate 10b, a first insulating layer 12 disposed on a side of the active layer 11 away from the substrate, a gate metal layer disposed on a side of the first insulating layer 12 away from the substrate, the gate metal layer may include a gate electrode 13 and a reflective layer 14, a second insulating layer 15 disposed on a side of the gate metal layer away from the substrate, a third insulating layer 16 disposed on a side of the second insulating layer 15 away from the substrate, and a source drain electrode layer disposed on a side of the third insulating layer 16 away from the substrate, the source drain electrode layer may include a source electrode 17, a drain electrode 17, and a source electrode, The light-emitting diode comprises a drain electrode 18 and a photosensitive device 19, a fourth insulating layer 20 arranged on one side, far away from the substrate, of the source-drain electrode layer, an anode 21 arranged on one side, far away from the substrate, of the fourth insulating layer 20, a pixel defining layer 22 arranged on one side, far away from the substrate, of the anode 21, a light-emitting layer 23 arranged on one side, far away from the substrate, of the pixel defining layer 22, an encapsulating layer 24 arranged on one side, far away from the substrate, of the light-emitting layer 23, and a cover plate 25 arranged on one side, far away from the substrate, of the. A cathode (not shown in fig. 5) is also provided between the light-emitting layer 23 and the encapsulation layer 24.

By disposing the reflective layer 14 on the first gate metal layer or the second gate metal layer, the distance between the reflective layer 14 and the cover plate 25 is shorter, the loss of signal light (light reflected by a finger) is smaller, and the signal-to-noise ratio can be improved, as compared with a case where the reflective layer 14 is disposed on the light shielding layer. In addition, when the position of the photosensitive device 19 is not changed and the reflective layer 14 is disposed on the first gate metal layer or the second gate metal layer, the distance between the reflective layer 14 and the photosensitive device 19 is smaller, the loss of signal light is smaller, and the signal-to-noise ratio can be improved.

Fig. 6 is a schematic diagram of a display substrate according to an exemplary embodiment. As shown in fig. 6, in the present embodiment, the position of the reflective layer 14 is the same as that of the embodiment shown in fig. 5, and may be disposed in the same layer as the light shielding layer. In this embodiment, the photosensitive device 19 may be disposed on the surface of the second substrate 10b, the first insulating layer 12, the second insulating layer 15, and the third insulating layer 16 are provided with via holes exposing the photosensitive device 19, and the fourth insulating layer 20 covers the photosensitive device 19. Compared with the scheme shown in fig. 5, the scheme provided by the embodiment shortens the distance between the photosensitive device 19 and the reflective layer 14, reduces the loss of signal light, and enhances the signal-to-noise ratio. In another embodiment, the photosensitive device 19 may be disposed in other film layers between the anode 21 and the reflective layer 14, for example, the photosensitive device 19 may be disposed in the same layer as the gate electrode 13, and so on.

Fig. 7 is a schematic view of a display substrate according to another embodiment. In this embodiment, the reflective layer 14 may be disposed on the same layer as the light shielding layer, and in addition, on the side of the reflective layer 14 away from the substrate, the light shielding layer is disposed to shield light from the side of the reflective layer 14 away from the substrate, so as to reduce noise light, and the light shielding layer includes a light-transmitting portion through which the finger-reflected light passes. Similar to the scheme shown in fig. 3, the anode 21 can be used as a light shielding layer, that is, the range of the anode 21 is enlarged, and a hole or a gap is formed in the path of the finger reflected light. As shown in fig. 7, in the present embodiment, the reflective layer 14 is disposed between the first substrate 10a and the second substrate 10b, the anode 21 blocks other light rays (such as ambient light, and light rays emitted from the light-emitting layer 23 reflected by other film layers of the display substrate) from the anode 21 away from the substrate side, and the anode 21 is provided with a hole or a slit for the finger to pass through, and to enter the reflective layer 14, and then enter the photosensitive device 19. The scheme provided by the embodiment reduces the ambient light received by the photosensitive device and improves the signal-to-noise ratio.

Fig. 8 is a schematic view of a display substrate according to another embodiment. In this embodiment, similar to the scheme shown in fig. 6, the reflective layer 14 may be disposed on the same layer as the light shielding layer, the photosensitive device 19 may be disposed on the surface of the second substrate 10b, the first insulating layer 12, the second insulating layer 15, and the third insulating layer 16 are provided with via holes exposing the photosensitive device 19, and the fourth insulating layer 20 covers the photosensitive device 19. In this embodiment, a light shielding layer is disposed on the side of the reflective layer 14 away from the substrate to shield light from the side of the reflective layer away from the substrate, so as to reduce noise light. Similar to the scheme shown in fig. 3, the anode can be used as a light shielding layer, that is, the range of the anode is enlarged, and a hole or a gap is formed in the path of the finger reflected light.

Fig. 9 is a schematic view of a display substrate according to another embodiment. In this embodiment, the reflective layer 14 may be disposed on the same layer as the light shielding layer, and the photosensitive device 19 may be disposed on the same layer as the source/drain electrode layer, or the photosensitive device 19 may be disposed on the surface of the substrate, and similar to the scheme described in fig. 4, the light collector 40 may be disposed on the side of the reflective layer 14 away from the substrate. The condenser 40 may refract incident light such that the incident light is condensed. The condenser 40 may condense the light emitted from the light emitting layer 23 and reflected by the finger to be incident on the reflective layer 14. The scheme provided by the embodiment can enhance the signal light and improve the signal-to-noise ratio.

In an exemplary embodiment, a two-layer reflective layer pattern may be prepared using a metal film layer of FMLOC after TFE, the two reflective layers having staggered overlapping portions to facilitate light reflection. In addition, the light blocking effect of FMLOC metal is utilized to prevent the photosensitive device from receiving external ambient light.

Fig. 10 is a schematic view of a display substrate according to another embodiment. As shown in fig. 10, the display substrate provided in this embodiment includes a substrate, where the substrate may include a first substrate 10a and a second substrate 10b, the display substrate further includes an active layer 11 disposed on the substrate, a first insulating layer 12 disposed on a side of the active layer 11 away from the substrate, a gate electrode 13 disposed on a side of the first insulating layer 12 away from the substrate, a second insulating layer 15 disposed on a side of the gate electrode 13 away from the substrate, a third insulating layer 16 disposed on a side of the second insulating layer 15 away from the substrate, a source and drain electrode layer disposed on a side of the third insulating layer 16 away from the substrate, where the source and drain electrode layer may include a source electrode 17 and a drain electrode 18, a fourth insulating layer 20 disposed on a side of the source and drain electrode layer away from the substrate, and an anode 21 disposed on a side of the fourth insulating layer 20 away from the substrate, the light-emitting diode comprises a pixel defining layer 22 arranged on one side of the anode 21 far away from a substrate, a light-emitting layer 23 and a photosensitive device 19 arranged on one side of the pixel defining layer 22 far away from the substrate, an encapsulating layer 24 arranged on one side of the light-emitting layer 23 and the photosensitive device 19 far away from the substrate, a first reflecting layer 27 arranged on one side of the encapsulating layer 24 far away from the substrate, a fifth insulating layer 26 arranged on one side of the first reflecting layer 27 far away from the substrate, a second reflecting layer 28 arranged on one side of the fifth insulating layer 26 far away from the substrate, and a cover plate 25 arranged on one side of the second reflecting layer 28 far away from the substrate. A cathode (not shown in fig. 1) is also provided between the light-emitting layer 23 and the encapsulation layer 24. On a plane parallel to the substrate, an orthographic projection of the first reflecting layer 27 overlaps with an orthographic projection of the second reflecting layer 28, a part of the orthographic projection of the first reflecting layer 27 is positioned outside the orthographic projection of the second reflecting layer 28, the orthographic projection of the first reflecting layer 27 and the orthographic projection of the second reflecting layer 28 are positioned outside the orthographic projection of the light emitting layer 23, and the orthographic projection of the photosensitive device 19 is at least partially positioned outside the orthographic projection of the first reflecting layer 27. The orthographic projection of said photosensitive device 19 lies at least partially within the orthographic projection of said second reflective layer 28, in a plane parallel to said substrate.

In the present embodiment, the first reflective layer 27 and the second reflective layer 28 constitute the reflective structure.

In this embodiment, the signal light from the light-emitting layer 23 is reflected by the finger 30 and enters the first reflective layer 27, and the signal light enters the photosensitive device 19 after being reflected one or more times between the first reflective layer 27 and the second reflective layer 28. In addition, the second reflective layer 28 can shield noise light, preventing the noise light from entering the photosensitive device 19.

In the present embodiment, the first reflective layer 27 and the second reflective layer 28 reflect the reflected light from the finger, and the second reflective layer 28 blocks the noise light, so that the signal-to-noise ratio can be improved.

In an exemplary embodiment, the fifth insulating layer 26 may be silicon oxide SiOx, silicon nitride SiNx, silicon oxynitride SiON, or the like, and may have a single-layer structure or a multi-layer composite structure.

In an exemplary embodiment, the first reflective layer 27 and the second reflective layer 28 may be made of opaque metal such as lithium, aluminum, magnesium, silver, nickel, chromium, molybdenum, copper, titanium, or an alloy of these materials.

In an exemplary embodiment, an orthographic projection of the photosensitive device 19 may be located within an orthographic projection of the second reflective layer 28. In this embodiment, the second reflective layer 28 shields the photosensitive device, so that noise light entering the photosensitive device is reduced, and the signal-to-noise ratio is improved.

In this embodiment, the second reflective layer 28 is multiplexed as a light shielding structure, and in another embodiment, a separate light shielding structure may be provided to shield the photosensitive device 19.

In an exemplary embodiment, an orthographic projection of the first reflective layer 27 may be annular in a plane parallel to the substrate, the orthographic projection of the first reflective layer 27 surrounding the orthographic projection of the light-sensing device 19. As shown in fig. 11, the orthographic projection of the first reflective layer 27 may for example be a square ring and the orthographic projection of the light-sensing device 19 may be located within the inner ring of the orthographic projection of the first reflective layer 27 in a plane parallel to the substrate. In another embodiment, the orthographic projection of said photosensitive device 19 may be partly within the inner ring of the orthographic projection of said first reflective layer 27 and partly within the orthographic projection of said first reflective layer 27. The shape of the orthographic projection of the first reflective layer 27 shown in fig. 11 is merely an example, and may be other shapes such as a circular ring, a shaped ring, and the like. The orthographic shape of the second reflective layer 28 can be square, circular, shaped, and the like.

Fig. 12 is a plan view of a light emitting device, a light sensing device, and a reflective structure provided in an exemplary embodiment. As shown in fig. 12, in the present embodiment, the light emitting devices may include a red light emitting device (R), a green light emitting device (G), and a blue light emitting device (B). The orthographic projection of light emitting device 31 may be outside the orthographic projection of light sensing device 19 and light emitting device 31 may be outside the orthographic projection of first reflective layer 27 and second reflective layer 28.

For the optical fingerprint function device implemented by the OPD, in this case, the photoelectric conversion layer and the light emitting layer of the photosensitive device may be disposed in the same layer. In order to prevent light emitted from the OLED from directly irradiating the photosensitive device, the OLED is preferably prepared using a Black Pixel Definition Layer (BPDL). In an exemplary embodiment, the light-sensing device 19 may be disposed in the same layer as the light-emitting device 31. For example, photosensitive device 19 includes a first pole 19-1, a photoelectric conversion layer 19-2, and a second pole (not shown in fig. 11). The first electrode 19-1 may be disposed in the same layer as the anode 21, the photoelectric conversion layer 19-2 may be disposed in the same layer as the light emitting layer 23, and the second electrode may be disposed in the same layer as the cathode of the light emitting device 31. A pixel defining layer 22 is disposed between the anode 21 and the light emitting layer 23. The first electrode 19-1 is connected to a drain electrode of a thin film transistor. The pixel defining layer 22 may be a black pixel defining layer so that it may be shielded from light and prevent light emitted from the light emitting layer 23 from directly entering the light sensing device 19. The pixel defining layer 22 may be prepared using an organic material containing a light-shielding colorant, such as a black pigment or black dye. In this embodiment, the material of the second pole of the photosensor 19 may be a transparent conductive material, the material of the second pole may be a metal Oxide such as zinc Oxide (ZnO), Indium Tin Oxide (ITO), Indium Gallium Zinc Oxide (IGZO), or may be another transparent conductive material, and the material is not limited herein. The light reflected by the first and second

reflective layers

27 and 28 may enter the photoelectric conversion layer from the second pole.

In an exemplary embodiment, the photosensitive device 19 may be located at the position shown in fig. 1 and 6, i.e. the photosensitive device 19 may be located at the side of the light emitting device close to the substrate, and the reflective structure comprises a first emissive layer 27 and a second reflective layer 28.

In an exemplary embodiment, the display substrate further includes a first touch electrode layer and a second touch electrode layer sequentially disposed on a side of the encapsulation layer away from the substrate, the first reflective layer 27 and the first touch electrode layer are disposed on the same layer, and the second reflective layer 28 and the second touch electrode layer are disposed on the same layer. In the embodiment, the reflecting layer is arranged on the same layer as the touch electrode, and the existing film layer is used for preparing the reflecting layer, so that the process is simplified, the cost is reduced, and the structure of the display substrate is simpler.

FIG. 13 is a schematic diagram of a display substrate provided in an exemplary implementation. As shown in fig. 13, the display substrate provided in this embodiment may include a condenser 40, similar to the display substrates shown in fig. 4 and 9. The condenser 40 may be disposed on one side of the fifth insulating layer 26 away from the substrate, light emitted from the light emitting layer 40 enters the condenser 40 after being reflected by a finger, and the light is converged by the condenser 40 and then enters the first reflecting layer 27, and then enters the photosensitive device 19 after being reflected by the first reflecting layer 27 and the second reflecting layer 28. In this embodiment, the light is converged by using the condenser, so that the intensity of light incident on the photosensor 19 can be enhanced, the sensitivity of fingerprint detection can be improved, and the contrast of a fingerprint image can be improved.

The embodiment of the disclosure also provides a display device, which includes the display substrate of the foregoing embodiment. The display device may be: any product or component with a display function, such as a mobile phone, a tablet computer, a television, a display, a notebook computer, a digital photo frame, a navigator and the like.

Although the embodiments of the present invention have been described above, the above description is only for the convenience of understanding the present invention, and is not intended to limit the present invention. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. The display substrate is characterized by comprising a substrate, a photosensitive device and a light-emitting device which are arranged on the substrate, and further comprising a reflecting structure and a light shielding structure which correspond to the photosensitive device, wherein the reflecting structure is configured to reflect light rays incident from the reflecting structure far away from the substrate side, and the reflected light rays at least partially face the corresponding photosensitive device; the light shielding structure is arranged on one side, far away from the substrate, of the photosensitive device, and on a plane parallel to the substrate, the orthographic projection of the photosensitive device is at least partially located in the orthographic projection of the light shielding structure.

2. The display substrate of claim 1, wherein the reflective structure comprises a reflective layer, the light-sensing device is disposed between the substrate and the light-emitting device, and the reflective layer is disposed between the light-sensing device and the substrate.

3. The display substrate according to claim 2, further comprising a thin film transistor disposed between the substrate and the light emitting device, wherein the thin film transistor comprises an active layer, a gate electrode, a source electrode, and a drain electrode sequentially disposed on the substrate, and the reflective layer is disposed on the same layer as the gate electrode.

4. The display substrate according to claim 2, wherein the display substrate further comprises a thin film transistor disposed between the base and the light emitting device, and a light shielding layer disposed on a side of the thin film transistor close to the base, and the reflective layer and the light shielding layer are disposed on the same layer.

5. The display substrate according to any one of claims 2 to 4, wherein the light-shielding structure comprises a light-shielding layer, the light-shielding layer is provided with a light-transmitting portion corresponding to the photosensitive device, an orthographic projection of the photosensitive device is located within an orthographic projection of the light-shielding layer, and an orthographic projection of the light-transmitting portion is located outside the orthographic projection of the photosensitive device.

6. The display substrate according to claim 5, wherein the light-emitting device comprises a first electrode, a light-emitting layer, and a second electrode, which are sequentially provided, wherein the first electrode is provided on a side of the light-emitting layer close to the substrate, and the first electrode is multiplexed as the light-shielding layer.

7. The display substrate according to claim 1, further comprising an encapsulation layer disposed on a side of the light emitting device away from the base, wherein the reflective structure is disposed on a side of the encapsulation layer away from the base, the reflective structure comprises a first reflective layer and a second reflective layer sequentially disposed, the first reflective layer is disposed on a side of the second reflective layer close to the base, the light emitting device comprises a light emitting layer, an orthographic projection of the first reflective layer overlaps an orthographic projection of the second reflective layer on a plane parallel to the base, the orthographic projection of the first reflective layer is outside the orthographic projection of the second reflective layer, and the orthographic projection of the first reflective layer and the orthographic projection of the second reflective layer are outside the orthographic projection of the light emitting layer.

8. The display substrate of claim 7, wherein the second reflective layer is multiplexed into the light blocking structure.

9. The display substrate of claim 7, wherein an orthographic projection of the first reflective layer on a plane parallel to the base is annular, and wherein the orthographic projection of the first reflective layer surrounds an orthographic projection of the light-sensitive device.

10. The display substrate according to claim 7, further comprising a first touch electrode layer and a second touch electrode layer sequentially disposed on a side of the encapsulation layer away from the substrate, wherein the first reflective layer and the first touch electrode layer are disposed on the same layer, and the second reflective layer and the second touch electrode layer are disposed on the same layer.

11. The display substrate according to claim 7, wherein the light emitting device further comprises a first electrode and a second electrode respectively disposed on two sides of the light emitting layer, the first electrode is disposed on one side of the light emitting layer close to the substrate, the photosensitive device and the light emitting device are disposed in the same layer, a pixel defining layer is disposed between the first electrode and the light emitting layer, and the pixel defining layer is made of an opaque material.

12. The display substrate according to any one of claims 1 to 4 and 7 to 11, wherein the display substrate further comprises: and the condenser is arranged on one side of the reflecting structure, which is far away from the substrate, and at least part of light rays condensed by the condenser are incident to the reflecting structure.

13. A display device comprising the display substrate according to any one of claims 1 to 12.