CN112133199B

CN112133199B - Display panel and display device

Info

Publication number: CN112133199B
Application number: CN202011052725.7A
Authority: CN
Inventors: 张军; 吴晓晓; 陈国照
Original assignee: Xiamen Tianma Microelectronics Co Ltd
Current assignee: Xiamen Tianma Microelectronics Co Ltd
Priority date: 2020-09-29
Filing date: 2020-09-29
Publication date: 2022-08-23
Anticipated expiration: 2040-09-29
Also published as: CN112133199A

Abstract

The invention discloses a display panel and a display device, comprising: a display area and a non-display area surrounding the display area; the display area is provided with a plurality of pixels arranged in an array and at least one fingerprint identification unit; the fingerprint identification unit comprises a fingerprint identification element and a fingerprint identification driving circuit; the fingerprint identification element at least comprises a first electrode and a second electrode; further comprising: a substrate base plate; the common electrode layer and the first metal layer are positioned on one side of the substrate base plate and are insulated and spaced, and the first metal layer is positioned on one side of the common electrode layer close to the substrate base plate; the common electrode layer comprises a common electrode for receiving a common voltage signal; the first metal layer comprises a first subsection which is multiplexed as a first electrode of the fingerprint identification element, and the first subsection is electrically connected with the driving chip and used for receiving a bias voltage signal transmitted by the driving chip, so that the display effect of the display panel is improved.

Description

Display panel and display device

Technical Field

The invention relates to the technical field of display panels, in particular to a display panel and a display device.

Background

The fingerprint is a name for identifying biological characteristics because of the lifelong invariance, uniqueness and convenience. In particular, in the display device, functions such as unlocking and payment of the display device can be realized by performing fingerprint recognition on a user.

At present, in order to realize full-screen display of a display panel, a pixel unit is usually disposed in an open area of a display area of the display panel, and a fingerprint identification unit is disposed in a non-open area of the display panel, wherein the fingerprint identification unit includes a fingerprint identification driving circuit and a fingerprint identification element, and a pixel circuit of the pixel unit is disposed in the non-open area. When the display panel is in a fingerprint identification stage, the first electrode of the fingerprint identification element receives a bias signal provided by the fingerprint identification driving circuit, and at the moment, the fingerprint identification element collects an optical signal returned by a finger, converts the optical signal into an electric signal and outputs the electric signal through the fingerprint identification driving circuit to realize fingerprint identification. When the display panel is in a display stage, the pixel circuit drives the pixel unit to emit light, and the display of the display panel is realized.

In the prior art, because the fingerprint identification unit and the pixel circuit in the display panel with the fingerprint identification function share the common electrode, the load on the common electrode is increased, so that the common voltage signal of the common electrode in the pixel unit is influenced, and the display effect of the display panel is further influenced.

Disclosure of Invention

Embodiments of the present invention provide a display panel and a display device, so as to reduce a load on a common electrode in the display panel and improve a display effect of the display panel.

In a first aspect, an embodiment of the present invention provides a display panel, including: a display area and a non-display area surrounding the display area; the display area is provided with a plurality of pixels arranged in an array and at least one fingerprint identification unit; the fingerprint identification unit comprises a fingerprint identification element and a fingerprint identification driving circuit; the fingerprint identification element comprises at least a first electrode and a second electrode;

the display panel further includes:

a substrate base plate;

the common electrode layer and the first metal layer are positioned on one side of the substrate base plate and are insulated and spaced, and the first metal layer is positioned on one side of the common electrode layer close to the substrate base plate; the common electrode layer comprises a common electrode for receiving a common voltage signal; the first metal layer comprises a first subsection, the first subsection is multiplexed to be a first electrode of the fingerprint identification element, and the first subsection is electrically connected with a driving chip and used for receiving a bias signal transmitted by the driving chip.

In a second aspect, an embodiment of the present invention further provides a display device, including the display panel according to any one of the first aspects.

According to the display panel and the display device provided by the embodiment of the invention, the common electrode of the pixel and the first metal layer for transmitting the bias signal to the first electrode of the fingerprint identification element are arranged at different layers and are arranged at intervals in an insulating manner, so that when the display panel is in a display stage, a common voltage signal received by the common electrode of the pixel positioned in the fingerprint identification area is not influenced by the fingerprint identification unit, on one hand, the load capacity of the common electrode in the display panel can be reduced, on the other hand, the common voltage signal received by the common electrode of the pixel in the fingerprint identification area is ensured to be the same as the common voltage signal received by the common electrode of the pixel in the non-fingerprint identification area, the uniformity of a display picture of the display panel in the fingerprint identification area and the non-fingerprint identification area is ensured, and the display effect of the display panel is improved.

Drawings

Fig. 1 is a schematic circuit diagram of a display panel provided in the prior art;

fig. 2 is a schematic top view of a display panel according to an embodiment of the present invention;

fig. 3 is a schematic diagram of a partial film structure of a display panel according to an embodiment of the present invention;

FIG. 4 is a schematic diagram of a partial film structure of another display panel according to an embodiment of the present invention;

FIG. 5 is a schematic diagram of a partial film structure of another display panel according to an embodiment of the present invention;

FIG. 6 is a schematic diagram of a top view structure of another display panel according to an embodiment of the present invention;

FIG. 7 is a schematic diagram of a partial film structure of another display panel according to an embodiment of the present invention;

fig. 8 is a schematic circuit diagram of a fingerprint identification driving circuit according to an embodiment of the present invention;

fig. 9 is a schematic diagram illustrating a top view structure of a film layer of a display panel according to an embodiment of the present invention;

FIG. 10 is a schematic diagram of a cross-sectional film structure of the display panel provided in FIG. 9 along A-A';

fig. 11 is a schematic top view illustrating a display panel according to another embodiment of the present invention;

fig. 12 is a schematic top view illustrating a display panel according to another embodiment of the present invention;

FIG. 13 is a schematic diagram of a partial film structure of another display panel according to an embodiment of the present invention;

FIG. 14 is a schematic diagram of a partial film structure of another display panel according to an embodiment of the present invention;

FIG. 15 is a schematic diagram of a partial film structure of another display panel according to an embodiment of the present invention;

FIG. 16 is a schematic diagram of a partial film structure of another display panel according to an embodiment of the present invention;

FIG. 17 is a schematic diagram of a partial film structure of another display panel according to an embodiment of the present invention;

fig. 18 is a schematic structural diagram of a display device according to an embodiment of the present invention.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some of the structures related to the present invention are shown in the drawings, not all of the structures.

As described in the background art, in order to realize full-screen display of the display panel, a display unit is usually disposed in an open area of the display panel, and a fingerprint identification unit and a pixel circuit are disposed in a non-open area of the display panel, where the fingerprint identification unit includes a fingerprint identification element and a fingerprint identification driving circuit, the fingerprint identification driving circuit can drive the corresponding fingerprint identification element to perform fingerprint identification, and the pixel circuit can drive the display unit to perform display. Fig. 1 is a schematic circuit diagram of a display panel provided in the prior art, and as shown in fig. 1, a circuit disposed in the display panel includes a pixel circuit 100' and a fingerprint identification driving circuit 200', where the fingerprint identification driving circuit 200' includes a gate transistor T1, a driving transistor T2, a selection output transistor T3, and a storage capacitor C1, a first electrode of a fingerprint identification element Fp and a first end of the storage capacitor C1 are both electrically connected to a signal input end Com of the fingerprint identification driving circuit 200', and the pixel circuit 100' includes a first driving transistor T4. When the display panel is in the fingerprint identification stage, the signal input end Com of the fingerprint identification driving circuit receives a common voltage signal and provides the common voltage signal to the first electrode of the fingerprint identification element FP, and the fingerprint identification element FP collects an optical signal returned by a finger, converts the optical signal into an electric signal, and outputs the electric signal through the driving transistor T2 and the selective output transistor T3 to realize the fingerprint identification function. When the display panel enters the display phase, the scan signal Gata controls the first driving transistor T4 to be turned on, so that the Data signal Data is written into the display unit, and the display panel performs display.

However, since the first electrode of the fingerprint identification element FP and the common electrode of the pixel circuit both receive the common voltage signal input by the signal input terminal Com, when the display panel is in a display stage, on one hand, the fingerprint identification driving electrically connected to the common electrode may increase the load on the common electrode, thereby affecting the common voltage signal of the common electrode in the pixel unit, and further affecting the display effect of the display panel. On the other hand, since the storage capacitor C1 of the fingerprint identification driving circuit affects the common voltage signal inputted to the common electrode in the pixel circuit from the signal input terminal Com, the display luminance of the display unit in the fingerprint identification area is different from that of the display unit in the non-fingerprint identification area, which affects the display effect of the display panel.

To solve the above technical problem, an embodiment of the present invention provides a display panel, including: a display area and a non-display area surrounding the display area; the display area is provided with a plurality of pixels arranged in an array and at least one fingerprint identification unit; the fingerprint identification unit comprises a fingerprint identification element and a fingerprint identification driving circuit; the fingerprint identification element comprises at least a first electrode and a second electrode; the display panel further includes: a substrate base plate; the common electrode layer and the first metal layer are positioned on one side of the substrate base plate and are insulated and spaced, and the first metal layer is positioned on one side of the common electrode layer close to the substrate base plate; the common electrode layer comprises a common electrode for receiving a common voltage signal; the first metal layer comprises a first subsection, the first subsection is multiplexed as a first electrode of the fingerprint identification element, and the first subsection is electrically connected with the driving chip and used for receiving a bias signal transmitted by the driving chip.

By adopting the technical scheme, the first metal layer is arranged on one side of the common electrode layer close to the substrate and is insulated from the common electrode layer, the common electrode of the common electrode layer is used for receiving a common voltage signal, and the first part of the first metal layer is used for receiving a bias signal transmitted by the driving chip; because the common electrode layer and the first metal layer are arranged at intervals in an insulating way, the common electrode and the first branch part for transmitting the bias voltage signal are mutually insulated, and therefore when the display panel is in a display stage, on one hand, the common voltage only needs to charge the common electrode of the pixel, the load on the common electrode is reduced, the accuracy of the common voltage signal transmitted to each pixel is ensured, and the power consumption of the display panel is reduced. On the other hand, because the common voltage signal received by the pixel in the fingerprint identification area through the common electrode is different from the common voltage signal received by the pixel in the non-fingerprint identification area through the common electrode, the influence of the fingerprint identification driving circuit in the fingerprint identification area on the common voltage signal received by the common electrode of the pixel driving circuit is avoided, the uniformity of the brightness of the display units in the fingerprint identification area and the non-fingerprint identification area in the display panel is ensured, and the display effect of the display panel is improved.

In the embodiment of the invention, the display area of the display panel can comprise a fingerprint identification area and a non-fingerprint identification area, and the display uniformity of the fingerprint identification area and the non-fingerprint identification area can be ensured by arranging the first subsection for transmitting the bias signal and the common voltage signal of the pixels at different layers; or, the display panel may be a display panel capable of realizing full-screen fingerprint identification, at this time, all display areas of the display panel are fingerprint identification areas, and the first sub-part for transmitting the bias signal and the common voltage signals of the pixels are arranged on different layers, so that the load on the common electrode can be reduced, the accuracy of the common voltage signals transmitted to the pixels can be ensured, and the display effect of the display panel can be improved; meanwhile, the common voltage only needs to charge the common electrode of the pixel in the display stage, and the bias voltage signal only needs to be provided to each fingerprint identification unit in the fingerprint identification stage, so that the load capacity of the display stage and the load capacity of the fingerprint identification stage are both in a descending trend, and the reduction of the power consumption of the display panel is facilitated. For convenience of description, in the embodiments of the present invention, the display area of the display panel includes a fingerprint identification area and a non-fingerprint identification area, and the technical solutions of the embodiments of the present invention are exemplarily described.

The above is the core idea of the present invention, and based on the embodiments of the present invention, a person skilled in the art can obtain all other embodiments without creative efforts, which belong to the protection scope of the present invention. The technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

Fig. 2 is a schematic top view structure diagram of a display panel according to an embodiment of the present invention, and fig. 3 is a schematic partial film structure diagram of a display panel according to an embodiment of the present invention, as shown in fig. 2 and fig. 3, the display panel includes a display area 100 and a non-display area 200 surrounding the display area 100, the display area 100 is provided with a plurality of pixels 110 arranged in an array and at least one fingerprint identification unit 120, the fingerprint identification unit 120 includes a fingerprint identification element 121 and a fingerprint identification driving circuit 122, and the fingerprint identification element 121 includes at least a first electrode 11 and a second electrode 12. The display panel further comprises a substrate base plate 10, a common electrode layer 20 and a first metal layer 30 which are located on one side of the substrate base plate 10 and are insulated and spaced, the first metal layer 30 is located on one side of the common electrode layer 20 close to the substrate base plate 10, the common electrode layer 20 comprises a common electrode and is used for receiving a common voltage signal, the first metal layer 30 comprises a first branch portion 31, the first branch portion 31 is multiplexed into a first electrode 11 of the fingerprint identification element 121, and the first branch portion 31 is electrically connected with the driving chip and is used for receiving a bias signal transmitted by the driving chip.

It should be noted that fig. 2 is an exemplary diagram of an embodiment of the present invention, and fig. 2 exemplarily shows that the AA area is a fingerprint identification area, the BB area is a non-fingerprint identification area, that is, the fingerprint identification unit 120 is disposed at a corresponding position of the AA area, and the fingerprint identification unit 120 is not disposed in the BB area. In addition, fig. 2 exemplarily shows that three pixels 110 correspond to one fingerprint identification unit 120, and one pixel 110 may also correspond to one fingerprint identification unit 120, which is not specifically limited in the embodiment of the present invention.

Illustratively, with continuing reference to fig. 2 and 3, the common electrode layer 20 and the first metal layer 30 disposed on the substrate 10 side of the display panel are insulated and spaced such that the first subsection 31 located on the first metal layer 30 and the common electrode located on the common electrode layer 20 are insulated from each other. At this time, when the display panel is in the fingerprint identification stage, the first electrode 11 of the fingerprint identification element 121 in the fingerprint identification area AA in the display panel receives the bias signal output by the driving chip through the first subsection 31 located on the first metal layer 30, so that after the fingerprint identification element 121 collects the optical signal returned by the finger and converts the optical signal into an electrical signal, the electrical signal can be output through the fingerprint identification driving circuit 122, thereby implementing the fingerprint identification function; when the display panel is in the display stage, the common electrodes of the pixels 110 in the fingerprint identification area AA and the pixels 110 in the non-fingerprint identification area BB receive a common voltage signal to control the pixels to display. In this way, the common electrode in the pixel 110 receiving the common voltage signal is located on the common electrode layer 20, and the first sub-portion 31 transmitting the bias signal to the first electrode 11 of the fingerprint identification element 121 is located on the first metal layer 30, so that the bias signal transmitted by the first sub-portion 31 and the common voltage signal received by the common electrode do not interfere with each other, when the display panel is in the display stage, the common voltage signal received by the common electrode located in the fingerprint identification area AA is not affected by the fingerprint identification driving circuit 122, and the common voltage signal received by the common electrode in the fingerprint identification area AA is ensured to be consistent with the common voltage signal received by the common electrode in the non-fingerprint identification area BB, so that uniformity of a displayed image of pixels in the fingerprint identification area AA and pixels in the non-fingerprint identification area BB can be ensured, and the display effect of the display panel is improved. Meanwhile, in the display stage, the common voltage only needs to charge the common electrode of the pixel, so that the load on the common electrode in the display panel can be reduced, and the reduction of the power consumption of the display panel is facilitated; accordingly, in the fingerprint identification stage, the bias signal only needs to be provided to the fingerprint identification unit, which is also beneficial to reducing the power consumption of the display panel.

Meanwhile, the first electrode 11 of the fingerprint identification element 121 is reused as the first subsection 31 of the first metal layer 30, so that a film layer is not required to be additionally arranged on the first electrode 11 of the fingerprint identification element 121, for example, the first electrode 11 of the fingerprint identification element 121 can be prepared by using the first metal layer 30, and thus, the structure of the display panel can be simplified without additionally arranging the first electrode of the fingerprint identification element 121, which is beneficial to simplifying the process of the display panel and lightening and thinning the display panel.

It should be noted that fig. 3 is only an exemplary diagram of an embodiment of the present invention, fig. 3 only shows a relative film layer relationship between the common electrode layer 20, the first metal layer 30 and the substrate 10, and between the common electrode layer 20 and the first metal layer 30, other functional film layers may also be disposed between the first metal layer 30 and the substrate 10, and other functional film layers may also be disposed on a side of the common electrode layer 20 away from the substrate 10.

Optionally, on the basis of the foregoing embodiment, fig. 4 is a schematic view of a partial film structure of another display panel provided in the embodiment of the present invention, and as shown in fig. 4, the display panel further includes a collimating light-shielding layer 40, the collimating light-shielding layer 40 includes a first through hole 41, a vertical projection of the first through hole 41 on the substrate 10 overlaps a vertical projection of the fingerprint identification element 121 on the substrate 10, and the first metal layer 30 is located between the collimating light-shielding layer and the substrate 10.

In this way, by providing the collimating light-shielding layer 40 on the side of the first metal layer 30 away from the substrate 10, the collimating light-shielding layer 40 can be used as a part of the collimating hole, so that the optical signal reflected by the finger can reach the fingerprint identification element 121 through the first through hole 41 of the collimating light-shielding layer 40, thereby preventing the optical signal reflected by the finger received by two adjacent fingerprint identification elements 121 from generating crosstalk, and improving the accuracy of fingerprint identification.

Alternatively, the first metal layer 30 may be a transparent metal layer, and the material of the transparent metal layer is, for example, indium tin oxide or the like. At this time, after the optical signal reflected by the finger reaches the first metal layer 30 through the first through hole 41 of the collimating and light-shielding layer 40, the optical signal can pass through the first metal layer 30 and be received by the fingerprint identification element 121, so as to prevent the optical signal reflected by the finger from being shielded by the first metal layer 30, and the fingerprint identification element 121 cannot receive the optical signal reflected by the finger and influence fingerprint identification. As such, providing the first metal layer 30 as a transparent metal layer can improve the accuracy of fingerprint identification.

Optionally, fig. 5 is a schematic view of a partial film structure of another display panel according to an embodiment of the present invention, and as shown in fig. 5, the fingerprint identification device further includes a PIN junction 13 located between the first electrode 11 and the second electrode 12, the first metal layer 30 further includes a plurality of collimating and light-shielding portions 40, the first metal layer 30 includes a first via hole 32, and the first via hole 32 is located in the first sub-portion 31.

Thus, the collimating and light-shielding part 40 is disposed on the first metal layer 30, so that the first metal layer 30 can shield light, and a collimating layer does not need to be disposed separately, thereby simplifying the manufacturing process, saving the manufacturing cost, and facilitating the lightening and thinning of the display panel. Meanwhile, when the first metal layer 30 includes the collimating and light-shielding portion 40, the first through hole 32 is formed in the first branch 31 of the first metal layer 30 to expose the fingerprint identification element 121, so that the optical signal reflected by the finger can reach the fingerprint identification element 121 through the first through hole 32 and be received by the fingerprint identification element 121, thereby achieving the effect of preventing the signals received by two adjacent fingerprint identification elements 121 from being cross-wound.

Optionally, with continued reference to fig. 5, the display panel further includes a first insulating layer 50 located on a side of the first metal layer 30 close to the fingerprint identification element 121, the first insulating layer 50 includes a second through hole 51, and the first sub-portion 31 is electrically connected to the PIN junction 13 through the second through hole 51.

In this way, since the first insulating layer 50 is disposed on one side of the first metal layer 30 close to the fingerprint identification device 121, and the second through hole 51 is disposed on the first insulating layer 50, the first subsection 31 of the first metal layer 30 can extend to the fingerprint identification device along the sidewall of the second through hole 51, so as to electrically connect the first subsection 31 of the first metal layer 30 and the fingerprint identification device 121.

Optionally, on the basis of the foregoing embodiment, fig. 6 is a schematic top view structure diagram of another display panel provided in the embodiment of the present invention, and fig. 7 is a schematic partial film structure diagram of another display panel provided in the embodiment of the present invention, as shown in fig. 6 and fig. 7, the display panel further includes a data signal line 60, the first metal layer 30 and the data signal line 60 are prepared in the same layer and process, the first metal layer 30 includes a third via 33, and the third via 33 is located in the first sub-portion 31.

As shown in fig. 6 and 7, the display panel includes a data signal line 60, wherein the data signal line 60 is used for transmitting a data signal to the pixel 110. Since the display stage and the fingerprint identification stage of the display panel are independent of each other, the first metal layer 30 and the data signal line 60 can be prepared in the same layer, when the display panel is in the display stage, the data signal line 60 receives the data signal output by the driving chip and transmits the data signal to the pixel 110, when the display panel is in the fingerprint identification stage, the first metal layer 30 receives the bias signal output by the driving chip and provides the bias signal to the first electrode 11 of the fingerprint identification element 121 through the first branch 31, and since the data signal line 60 and the film layer of the first metal layer 30 do not need to be respectively arranged, the process can be simplified, the production cost can be saved, and the display panel is light and thin.

Accordingly, the first subsection 31 of the first metal layer 30 may be provided with the third through hole 33 to expose the fingerprint identification element 121, so that the fingerprint light signal reflected by the finger can be received by the fingerprint identification element 121 through the third through hole 33, thereby improving the accuracy of fingerprint identification.

Optionally, on the basis of the foregoing embodiment, fig. 8 is a schematic circuit structure diagram of a fingerprint identification driving circuit provided in an embodiment of the present invention, fig. 9 is a schematic diagram of a top view structure of a film layer of a display panel provided in an embodiment of the present invention, fig. 10 is a schematic diagram of a film layer structure of a cross section a-a' in fig. 9, and with reference to fig. 8, fig. 9 and fig. 10, the fingerprint identification driving circuit at least includes a first capacitor Cst and a driving transistor Tsf, the second electrode 12 of the fingerprint identification element 121 is electrically connected to the gate 61 of the driving transistor Tsf and the first plate Cs1 of the first capacitor Cst, and the second plate Cs2 of the first capacitor Cst is electrically connected to the first metal layer 30. The display panel further includes a semiconductor layer 70 and a second metal layer 80 between the substrate 10 and the common electrode layer 20, and the first metal layer 30, the second metal layer 80 and the semiconductor layer 70 are disposed at an insulating interval, wherein the second metal layer 80 includes a second plate Cs2 of the first capacitor Cst and the gate electrode 61 of the driving transistor Tsf, and the semiconductor layer 70 includes a first plate Cs1 of the first capacitor Cst, the second electrode 12 of the fingerprint identification element 121 and the active layer 62 of the driving transistor Tsf. At this time, the second plate Cs2 of the first capacitor Cst may be electrically connected to the first metal layer 30 through the via hole to receive the bias signal Vbais transmitted by the first metal layer 30.

The second polar plate Cs2 of the first capacitor Cst of the fingerprint identification driving circuit and the gate 61 of the driving transistor Tsf are arranged on the second metal layer 80, so that the second polar plate Cs2 of the first capacitor Cst of the fingerprint identification driving circuit and the gate 61 of the driving transistor Tsf can be manufactured on the same layer, the process is simplified, the production cost is saved, a film layer is not required to be additionally arranged on the second polar plate Cs2 of the first capacitor Cst of the fingerprint identification driving circuit, and the display panel is favorable for being light and thin. Since the active layer 62 of the driving transistor Tsf is usually a semiconductor layer, which may be made of, for example, polysilicon, when part of the active layer 62 of the driving transistor Tsf is subjected to a conductive treatment, so that the treated active layer 62 can meet the conductive requirement, the active layer 62 of the driving transistor Tsf, the first plate Cs1 of the first capacitor Cst, and the second electrode 12 of the fingerprint identification element 121 may be disposed in the same layer, which is beneficial to the thinning of the display panel while ensuring the conductive performance of the first plate Cs1 and the second electrode 12.

Fig. 10 exemplarily shows a schematic diagram of a film structure of the fingerprint identification element 121 and the first capacitor Cst and the driving transistor Tsf in the fingerprint identification driving circuit, in which the fingerprint identification driving circuit further includes switching elements such as a gate transistor Tx and a selective output transistor Tsel, and the specific arrangement of the switching transistors is as shown in fig. 9.

Correspondingly, because the pixel circuit 123 is further disposed in the display area of the display panel, the pixel circuit 123 may control the pixels in the display area to perform light emitting display, and because the pixel circuit 123 may include at least one transistor, in this case, the gate of each transistor in the fingerprint identification driving circuit may be disposed in the same layer as the gate metal layer of the transistor in the pixel circuit 123, the active layer of each transistor in the fingerprint identification driving circuit may be disposed in the same layer as the active layer of the transistor in the pixel circuit 123, and the first pole and the second pole of each transistor in the fingerprint identification driving circuit may be disposed in the same layer as the source/drain electrodes of the transistor in the pixel circuit 123. Therefore, when the film layers of the pixel circuit 123 are formed, the fingerprint identification driving circuit and the fingerprint identification element can be formed at the same time, so that the process steps can be simplified, the production cost can be saved, and the film layers do not need to be additionally arranged for the fingerprint identification driving circuit and the fingerprint identification element in the display panel, thereby further facilitating the light and thin of the display panel.

It should be noted that fig. 9 and fig. 10 are only exemplary drawings of the embodiment of the present invention, in fig. 9 and fig. 10, a structure of the pixel circuit 123 is replaced by only one transistor, the pixel circuit 123 is not limited to include only one transistor, the pixel circuit 123 may further include other transistors, capacitors, and other devices, and this is not limited in the embodiment of the present invention. Meanwhile, the transistors shown in fig. 9 and 10 are top-gate transistors, and on the premise that the beneficial effects of the embodiments of the present invention can be achieved, the transistors in the pixel circuit and the fingerprint identification driving circuit may also be bottom-gate transistors, which is not specifically limited in the embodiments of the present invention. In addition, in order to clearly express the relationship between the films, the sizes of the transistor, the capacitor, and the separation distance between the transistor and the capacitor in fig. 9 and 10 are adaptively enlarged and reduced, which is not a practical design scale of the embodiment of the present invention.

It should be noted that fig. 9 and 10 exemplarily show that the second electrode 12 of the fingerprint identification element 121 and the first plate Cs1 of the first capacitor Cst are separately prepared, and the second electrode 12 of the fingerprint identification element 121 and the first plate Cs1 of the first capacitor Cst may also be configured as an integral structure, so as to reduce the process complexity.

Optionally, on the basis of the above embodiment, fig. 11 is a schematic top view structure diagram of another display panel according to an embodiment of the present invention, and with reference to fig. 3 and fig. 11, the non-display area 200 is provided with a bias signal bus 210, the bias signal bus 210 is located on at least one side of the display area 100, the display area 100 is further provided with a plurality of bias signal lines 220 extending along the first direction Y and arranged along the second direction X, the bias signal lines 220 are electrically connected to the first metal layer 30 and the bias signal bus 210, respectively, and the bias signal lines 220 receive a bias signal through the bias signal bus 210 and transmit the bias signal to the first electrodes 11 of the fingerprint identification elements 121 through the first metal layer 30.

When the bias signal lines 220 extend along the first direction Y and are arranged along the second direction, the bias signal bus lines 210 may be located in at least one side of the non-display area 200 of the display area 100, so that each bias signal line 220 can be electrically connected to the same bias signal bus line 210, and thus the bias signal provided by the driving chip can be transmitted to each bias signal line 220 through at least one bias signal bus line 210 and transmitted from the bias signal line 220 to the first electrode 11 of each fingerprint identification element 121 through the first metal layer 30.

It should be noted that fig. 11 is a diagram illustrating an embodiment of the present invention, and fig. 11 illustrates an example where the first direction Y is a row direction of the pixels, and the second direction X is a column direction of the pixels, where an extending direction of the bias signal line 220 may be consistent with an extending direction of the data signal line in the display panel; but in the embodiment of the invention, the following steps can be also included: the first direction is the column direction of the pixels, and the second direction is the row direction of the pixels, and the extending direction of the bias signal line 220 can be consistent with the extending direction of the scan signal line in the display panel.

Illustratively, as shown in fig. 12, the bias signal lines 220 extend in a first direction X parallel to a row direction of the pixels and are arranged in a second direction Y parallel to a column direction of the pixels; the bias signal bus lines 210 disposed in the non-display region of the display panel may extend along the second direction Y, so that each bias signal line 220 may be electrically connected to the same bias signal bus line 210, and thus the bias signal provided by the driving chip may be transmitted to each bias signal line 220 through at least one bias signal bus line 210, and transmitted from the bias signal line 220 to the first electrode 11 of each fingerprint identification element 121 through the first portion 31 of the first metal layer 30.

When the bias signal line 220 extends along the first direction Y, the bias signal received by the fingerprint identification device 121 close to the driving chip is larger, and the fingerprint identification device 121 far away from the driving chip along the first direction Y is connected to the longer bias signal line 220, so that a part of the bias signal is lost by the resistance of the bias signal line 220, and the bias signal actually provided to the fingerprint identification device 121 far away from the driving chip is reduced, thereby affecting the accuracy of the fingerprint identification result. Therefore, the bias signal line 220 is arranged to receive the bias signal through the bias signal bus 210, and the bias signal bus 210 is used to provide the bias signal to different bias signal lines, so as to ensure that the bias signals received by the fingerprint identification elements at different positions are the same, and improve the accuracy of the fingerprint identification result.

In addition, in the embodiment of the present invention, the bias signal bus 210 is located on at least one side of the display area 100, i.e. the bias signal bus 210 may be located on one side of the display area 100 (as shown in fig. 11), on two opposite sides (as shown in fig. 12), or around the display area 100. On the premise that the bias signal can be provided to each bias signal line 220 through the bias signal bus 210, the embodiment of the invention is not particularly limited to the number and the arrangement of the bias signal bus 210.

Optionally, on the basis of the foregoing embodiment, fig. 13 is a schematic view of a partial film structure of another display panel according to an embodiment of the present invention, as shown in fig. 13, the bias signal line 220 may be disposed on the same layer as the first sub-portion 31, that is, the first metal layer 30 includes the bias signal line 220 and the first sub-portion 31, and at this time, one end of the bias signal line 220 may be directly electrically connected to the first sub-portion 31. Thus, the bias signal lines 220 and the first parts 31 can be made of the same material in the same process, so that the process steps of the display panel can be simplified, and the cost of the display panel can be reduced.

Optionally, on the basis of the foregoing embodiment, fig. 14 is a schematic view of a partial film structure of another display panel provided in an embodiment of the present invention, and as shown in fig. 14, the display panel further includes: and a third metal layer 90 located on one side of the substrate base plate 10 and insulated and spaced from the first metal layer 30, wherein the third metal layer 90 includes a bias signal line 220, and the first metal layer 30 is electrically connected to the bias signal line 220 through a via 500.

When the bias signal line 220 transmits the bias signal through the bias signal bus 210, the bias signal line 220 may be insulated from the first metal layer 30, the bias signal line 220 is disposed in the third metal layer 90, the third metal layer 90 is insulated from the first metal layer 30, and the bias signal line 220 is electrically connected to the first metal layer 30 through the via 500, so that the first electrode 11 of the fingerprint identification device 121 receives the bias signal through the first metal layer 30.

It should be noted that fig. 14 exemplarily shows a manner that the first metal layer 30 and the third metal layer 90 are disposed at an insulating interval, where in fig. 14, the third metal layer 90 is disposed in the same layer as the second plate Cs2 of the first capacitor Cst, or as shown in fig. 15, the third metal layer 90 is disposed in a layered manner as the second plate Cs2 of the first capacitor Cst, and the first metal layer 30 is electrically connected to the bias signal line 220 through the via 500.

Optionally, on the basis of the foregoing embodiment, fig. 16 is a schematic view of a partial film structure of another display panel according to an embodiment of the present invention, as shown in fig. 16, the fingerprint identification driving circuit at least includes a driving transistor Tsf and a first capacitor Cst, the second electrode 12 of the fingerprint identification element 121 is electrically connected to the gate 61 of the driving transistor Tsf and the first plate Cs1 of the first capacitor Cst, the second plate Cs2 of the first capacitor Cst is electrically connected to the first metal layer 30, the third metal layer 90 further includes the second plate Cs2 of the first capacitor Cst and the gate 61 of the driving transistor Tsf, and one end of the bias signal line 220 is electrically connected to the second plate Cs2 of the first capacitor Cst. Thus, the bias signal line 220 is layered with the first sub-portion 31, and the bias signal line 220 can be electrically connected to the first metal layer 30 through the via 500; meanwhile, the bias signal line 220, the second plate Cs2 of the first capacitor Cst, and the gate 61 of the driving transistor Tsf are all disposed on the third metal layer 90, so that the structures disposed on the third metal layer 90 can be made of the same material in the same process, which is beneficial to simplifying the process steps of the display panel, reducing the cost of the display panel, and lightening and thinning the display panel.

Alternatively, referring to fig. 12 and 16, the fingerprint identification units 121 in the same row share the bias signal line 220, and the display area is further provided with a plurality of scan signal lines 230 extending along the first direction X and arranged along the second direction Y, and a plurality of data signal lines 240 extending along the second direction Y and arranged along the first direction X. The display panel further includes a fourth metal layer 400 located between the substrate 10 and the common electrode layer 20, and the first metal layer 30, the third metal layer 90 and the fourth metal layer 400 are disposed at an insulating interval, wherein the scan signal line 230 is located in the third metal layer 90, and the data signal line 60 is located in the fourth metal layer 400.

The pixels 110 in the same row share the scan signal line 230, and the scan signal line 230 can transmit a scan signal to the pixels 110, and the pixels 110 in the same column share the data signal line 60, and the data signal line 60 can transmit a data signal to the pixels 110. When the fingerprint identification units 120 in the same row share the bias signal line 220, the bias signal line 220 can transmit the bias signal to each fingerprint identification unit 120. At this time, the extending direction of the bias signal line 220 is the same as the extending direction of the scan signal line 230, and the bias signal line 220 and the scan signal line 230 can be arranged in the same layer, so that a mask plate does not need to be separately manufactured for the bias signal line 210, thereby saving the cost, reducing the process and improving the production efficiency.

Optionally, on the basis of the foregoing embodiment, fig. 17 is a schematic view of a partial film structure of another display panel according to an embodiment of the present invention, as shown in fig. 17, the fingerprint identification driving circuit at least includes a driving transistor Tsf and a first capacitor Cst, and the second electrode 12 of the fingerprint identification element 121 is electrically connected to the gate 61 of the driving transistor Tsf and the first plate 11 of the first capacitor Cst. The display panel further includes a second metal layer 80 located between the substrate 10 and the common electrode layer 20, and the first metal layer 30, the second metal layer 80 and the third metal layer 90 are disposed at an insulating interval, wherein the second metal layer 80 includes a gate 61 of the driving transistor Tsf and a second plate Cs2 of the first capacitor Cst, the bias signal line 220 is electrically connected to the second plate Cs2 of the first capacitor Cst through the lap joint structure 510, and the bias signal line 220 is further used for transmitting a bias signal to the second plate Cs2 of the first capacitor Cst.

At this time, the bias signal line 220 and the first sub-portion 31 are layered, the bias signal line 220 can be electrically connected to the first metal layer 30 through a via, and the bias signal line 220 is electrically connected to the second plate Cs2 of the first capacitor Cst through the lap joint structure 510, so that the bias signal transmitted by the bias signal line 220 can be respectively provided to the second plate Cs2 of the first capacitor Cst and the first electrode of the fingerprint identification element.

Optionally, referring to fig. 11 and 17, the fingerprint identification units in the same column share the bias signal line 220, the display area 100 is further provided with a plurality of scan signal lines 230 extending along the second direction X and arranged along the first direction Y, and a plurality of data signal lines 60 extending along the first direction Y and arranged along the second direction X, wherein the scan signal lines 230 are located on the second metal layer 80, and the data signal lines 60 are located on the third metal layer 90.

At this time, the extending direction of the bias signal line 220 is the same as the extending direction of the data signal line 60, and both the bias signal line 220 and the data signal line 60 can be disposed on the third metal layer 90, so that a mask plate does not need to be separately manufactured for the bias signal line 220, thereby saving the cost, reducing the manufacturing process and improving the production efficiency.

Embodiments of the present invention further provide a display device, where the display device includes the display panel provided in the embodiments of the present invention, and therefore the display device also has the beneficial effects of the display panel provided in the embodiments of the present invention, and the same points can be understood with reference to the above description, and are not described in detail below.

For example, fig. 15 is a schematic structural diagram of a display device according to an embodiment of the present invention. As shown in fig. 15, the display device 600 includes a display panel according to an embodiment of the present invention, and the display device 600 may be a mobile phone, a tablet computer, a smart wearable device (e.g., a smart watch), or other display devices with fingerprint identification function known to those skilled in the art, which is not limited in the present invention.

It is to be noted that the foregoing is only illustrative of the preferred embodiments of the present invention and the technical principles employed. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious changes, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in greater detail by the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the spirit of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A display panel, comprising: a display area and a non-display area surrounding the display area; the display area is provided with a plurality of pixels arranged in an array and at least one fingerprint identification unit; the fingerprint identification unit comprises a fingerprint identification element and a fingerprint identification driving circuit; the fingerprint identification element comprises at least a first electrode and a second electrode;

the display panel further includes:

a base substrate;

the common electrode layer and the first metal layer are positioned on one side of the substrate base plate and are insulated and spaced, and the first metal layer is positioned on one side of the common electrode layer close to the substrate base plate; the common electrode layer comprises a common electrode for receiving a common voltage signal; the first metal layer comprises a first subsection, the first subsection is multiplexed as a first electrode of the fingerprint identification element, and the first subsection is electrically connected with a driving chip and used for receiving a bias signal transmitted by the driving chip;

the fingerprint identification driving circuit at least comprises a first capacitor and a driving transistor; the second electrode of the fingerprint identification element is electrically connected with the grid electrode of the driving transistor and the first polar plate of the first capacitor; the second polar plate of the first capacitor is electrically connected with the first metal layer;

the display panel further comprises a semiconductor layer located between the substrate and the common electrode layer, the first metal layer is arranged at an interval in an insulating mode with the semiconductor layer, and the semiconductor layer comprises a first electrode plate of the first capacitor, a second electrode of the fingerprint identification element and an active layer of the driving transistor.

2. The display panel of claim 1, further comprising a collimating light shielding layer, wherein the collimating light shielding layer comprises a first through hole, and a vertical projection of the first through hole on the substrate overlaps a vertical projection of the fingerprint identification element on the substrate; the first metal layer is located between the collimation shading layer and the substrate.

3. The display panel according to claim 2, wherein the first metal layer is a transparent metal layer.

4. The display panel according to claim 1, wherein the fingerprint identification element further comprises a PIN junction between the first electrode and the second electrode;

the first metal layer further comprises a plurality of collimation shading parts;

the first metal layer comprises a first via; the first via is located at the first subsection.

5. The display panel according to claim 4, further comprising a first insulating layer on a side of the first metal layer adjacent to the fingerprint identification element, wherein the first insulating layer comprises a second via, and wherein the first segment electrically overlaps the PIN junction through the second via.

6. The display panel according to claim 1, wherein the display panel further comprises a data signal line;

the first metal layer and the data signal line are prepared in the same layer and process; the first metal layer comprises a third via; the third via is located at the first subsection.

7. The display panel according to claim 1, wherein the display panel further comprises a second metal layer between the base substrate and the common electrode layer; the first metal layer and the second metal layer are arranged at intervals in an insulating mode;

wherein the second metal layer includes a second plate of the first capacitor and a gate of the driving transistor.

8. The display panel according to claim 1, wherein the non-display region is provided with a bias signal bus line; the bias signal bus is positioned on at least one side of the display area; the display area is also provided with a plurality of bias signal lines which extend along the first direction and are arranged along the second direction;

the bias signal line is electrically connected with the first metal layer and the bias signal bus respectively; the bias signal line receives the bias signal through the bias signal bus and transmits the bias signal to the first electrode of each fingerprint identification element through the first metal layer.

9. The display panel according to claim 8, wherein the first metal layer further comprises the bias signal line, and wherein one end of the bias signal line is electrically connected to the first division portion.

10. The display panel according to claim 8, further comprising:

the third metal layer is positioned on one side of the substrate base plate and is insulated and arranged with the first metal layer at intervals;

wherein the third metal layer comprises the bias signal line; the first metal layer is electrically connected with the bias signal line through a via hole.

11. The display panel according to claim 10, wherein the third metal layer further includes a second plate of the first capacitor and a gate of the driving transistor, and wherein one end of the bias signal line is electrically connected to the second plate of the first capacitor.

12. The display panel according to claim 11, wherein the fingerprint identification units in a same row share the bias signal line;

the display area is also provided with a plurality of scanning signal lines which extend along the first direction and are arranged along the second direction, and a plurality of data signal lines which extend along the second direction and are arranged along the first direction;

the display panel further comprises a fourth metal layer positioned between the substrate base plate and the common electrode layer; the first metal layer, the third metal layer and the fourth metal layer are arranged at intervals in an insulating mode;

wherein the scanning signal line is located in the third metal layer; the data signal line is located on the fourth metal layer.

13. The display panel according to claim 10, further comprising a second metal layer between the substrate base plate and the common electrode layer; the first metal layer, the second metal layer and the third metal layer are arranged at intervals in an insulating mode;

the second metal layer comprises a grid electrode of the driving transistor and a second plate electrode of the first capacitor; the bias signal line is electrically connected with the second plate of the first capacitor through a lapping structure; the bias signal line is also used for transmitting the bias signal to the second plate of the first capacitor.

14. The display panel according to claim 13, wherein the fingerprint identification units in the same column share the bias signal line;

the display area is also provided with a plurality of scanning signal lines which extend along the second direction and are arranged along the first direction, and a plurality of data signal lines which extend along the first direction and are arranged along the second direction;

wherein the scanning signal line is located on the second metal layer; the data signal line is located in the third metal layer.

15. A display device characterized by comprising the display panel according to any one of claims 1 to 14.