Photoelectric detection circuit, driving method thereof, display panel and display device

Abstract

The photoelectric detection circuit, its driving method, display panel and display device provided by the embodiments of the present disclosure can, through the mutual cooperation of the driving control circuit and the output control circuit, generate an amplified detection current according to the electrical signal converted by the photoelectric conversion device, thereby improving the clarity of the obtained fingerprint picture and further improving the accuracy of fingerprint recognition.

Description

Technical Field

[0001] The present disclosure relates to the field of display technologies, and particularly to a photoelectric detection circuit, a driving method thereof, a display panel, and a display device. Background Art

[0002] Fingerprint detection and recognition, as a means of authentication, have been widely used and are almost one of the essential functions on electronic devices such as mobile phones and tablet computers. Common fingerprint detection methods include capacitive fingerprint detection, optical fingerprint detection, and ultrasonic detection, etc. Among them, optical fingerprint detection is the current mainstream trend. Summary of the Invention

[0003] The photoelectric detection circuit provided by an embodiment of the present disclosure includes:

[0004] A photoelectric conversion device configured to convert a received optical signal into an electrical signal;

[0005] A driving control circuit coupled to the photoelectric conversion device and configured to generate a detection current according to a signal at a detection control signal terminal and the electrical signal converted by the photoelectric conversion device;

[0006] An output control circuit coupled to the driving control circuit and configured to output the detection current to a detection terminal in response to a signal at a detection scan signal terminal.

[0007] In some examples, the driving control circuit includes:

[0008] A control circuit coupled to a first conversion electrode of the photoelectric conversion device and configured to pull down the voltage of the first conversion electrode in response to a signal at the detection control signal terminal;

[0009] A driving circuit coupled to the first conversion electrode of the photoelectric conversion device and configured to perform threshold compensation in response to a signal at a detection compensation signal terminal and generate a detection current according to the electrical signal.

[0010] In some examples, the control circuit includes: a capacitor;

[0011] A first electrode plate of the capacitor is coupled to the detection control signal terminal, and a second electrode plate of the capacitor is coupled to the first conversion electrode.

[0012] In some examples, the driving circuit includes: a detection driving transistor and a detection compensation transistor;

[0013] A gate of the detection driving transistor is coupled to the first conversion electrode, a first pole of the detection driving transistor is coupled to a first power supply terminal, and a second pole of the detection driving transistor is coupled to the output control circuit;

[0014] The gate of the detection compensation transistor is coupled to the detection compensation signal terminal, the first pole of the detection compensation transistor is coupled to the first pole of the detection driving transistor, and the second pole of the detection compensation transistor is coupled to the second pole of the detection driving transistor.

[0015] In some examples, the output control circuit includes: a detection scanning transistor;

[0016] The gate of the detection scanning transistor is coupled to the detection scanning signal terminal, the first pole of the detection scanning transistor is coupled to the driving circuit, and the second pole of the detection scanning transistor is coupled to the detection terminal.

[0017] The display panel provided by the embodiment of the present disclosure includes the above-mentioned optoelectronic detection circuit.

[0018] In some examples, the display panel further includes a substrate, a plurality of the optoelectronic detection units and a plurality of light-emitting sub-pixels located in the display area of the substrate; wherein, the orthographic projection of the light-emitting sub-pixel on the substrate and the orthographic projection of the optoelectronic detection unit on the substrate do not overlap;

[0019] The light-emitting sub-pixel includes a light-emitting device;

[0020] The optoelectronic detection unit includes the optoelectronic detection circuit.

[0021] In some examples, the first conversion electrode of the optoelectronic conversion device is provided with the same layer and the same material as the first light-emitting electrode of the light-emitting device;

[0022] And / or, the second conversion electrode of the optoelectronic conversion device is provided with the same layer and the same material as the second light-emitting electrode of the light-emitting device.

[0023] In some examples, the light-emitting sub-pixel further includes a driving circuit for driving the light-emitting device to emit light;

[0024] The gates of the transistors in the optoelectronic detection circuit and the gates of the transistors in the driving circuit are provided with the same layer and the same material;

[0025] And / or, the active layers of the transistors in the optoelectronic detection circuit and the active layers of the transistors in the driving circuit are provided with the same layer and the same material;

[0026] And / or, the source-drain electrodes of the transistors in the optoelectronic detection circuit and the source-drain electrodes of the transistors in the driving circuit are provided with the same layer and the same material.

[0027] The display device provided by the embodiment of the present disclosure includes the above-mentioned display panel.

[0028] In some examples, the display device further includes: a detection chip; wherein, the detection chip includes a data processing circuit and a plurality of signal transmission circuits;

[0029] The detection ends of a column of the photoelectric detection circuits are coupled to one of the signal transmission circuits, and the signal transmission circuit is configured to process the received detection current to obtain a target detection signal and send the target detection signal to the data processing circuit;

[0030] The data processing circuit is configured to perform fingerprint detection and recognition based on the target detection signal sent by the signal transmission circuit.

[0031] The driving method for the above-mentioned photoelectric detection circuit provided by an embodiment of the present disclosure includes:

[0032] In the first stage, a signal with a first voltage is loaded onto the detection control signal terminal;

[0033] In the second stage, a signal with a second voltage is loaded onto the detection control signal terminal, the photoelectric conversion device converts the received optical signal into an electrical signal, the driving control circuit receives the electrical signal and generates a detection current according to the electrical signal; the output control circuit outputs the detection current to the detection end in response to the signal of the detection scan signal terminal;

[0034] Wherein, the first voltage is greater than the second voltage.

[0035] In some examples, the first stage includes:

[0036] A reset compensation stage, a signal with a first level is loaded onto the detection compensation signal terminal, a signal with a first level is loaded onto the detection scan signal line, and a signal with the first voltage is loaded onto the detection control signal terminal.

[0037] In some examples, the second stage includes:

[0038] A conversion stage, a signal with a second level is loaded onto the detection compensation signal terminal, a signal with a first level is loaded onto the detection scan signal line, and a signal with the second voltage is loaded onto the detection control signal terminal;

[0039] An output stage, a signal with a second level is loaded onto the detection compensation signal terminal, a signal with a second level is loaded onto the detection scan signal line, and a signal with the second voltage is loaded onto the detection control signal terminal.

[0040] The photoelectric detection circuit, its driving method, display panel and display device provided by the embodiments of the present disclosure can, through the mutual cooperation of the driving control circuit and the output control circuit, generate an amplified detection current according to the electrical signal converted by the photoelectric conversion device, thereby improving the clarity of the obtained fingerprint picture and further improving the accuracy of fingerprint recognition. Description of the Drawings

[0041] Figure 1 Some structural schematic diagrams of the photoelectric detection circuit in the embodiments of the present disclosure;

[0042] Figure 2 Some other structural schematic diagrams of the photoelectric detection circuit in the embodiments of the present disclosure;

[0043] Figure 3 Some specific structural schematic diagrams of the photoelectric detection circuit in the embodiments of the present disclosure;

[0044] Figure 4 Flowcharts of some driving methods of the photoelectric detection circuit in the embodiments of the present disclosure;

[0045] Figure 5 Some signal timing diagrams in the embodiments of the present disclosure;

[0046] Figure 6 Some top view structural schematic diagrams of the display panel in the embodiments of the present disclosure;

[0047] Figure 7 Some partial cross-sectional structural schematic diagrams of the display panel in the embodiments of the present disclosure;

[0048] Figure 8 Some structural schematic diagrams of the display device in the embodiments of the present disclosure;

[0049] Figure 9 Some other structural schematic diagrams of the display device in the embodiments of the present disclosure;

[0050] Figure 10 Some other structural schematic diagrams of the display device in the embodiments of the present disclosure. Detailed Embodiments

[0051] To make the objectives, technical solutions and advantages of the embodiments of the present disclosure clearer, the technical solutions of the embodiments of the present disclosure will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present disclosure. Apparently, the described embodiments are some, but not all, of the embodiments of the present disclosure. And, without conflict, the embodiments and features in the present disclosure can be combined with each other. All other embodiments obtained by those of ordinary skill in the art based on the described embodiments of the present disclosure without creative efforts shall fall within the scope of protection of the present disclosure.

[0052] Unless otherwise defined, technical terms or scientific terms used in this disclosure shall have the ordinary meanings as understood by those of ordinary skill in the art to which this disclosure pertains. The "first", "second" and similar terms used in this disclosure do not denote any order, quantity or importance, but are only used to distinguish different components. Words such as "including" or "comprising" mean that the elements or objects appearing before this word cover the elements or objects listed after this word and their equivalents, without excluding other elements or objects. Words such as "connected" or "coupled" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect.

[0053] It should be noted that the sizes and shapes of the figures in the drawings do not reflect the true proportions, and the purpose is only to schematically illustrate the content of this disclosure. Also, the same or similar reference numerals throughout indicate the same or similar elements or elements having the same or similar functions.

[0054] In order to improve the integration of the display panel, a photoelectric detection circuit for optical fingerprint recognition can be integrated within the display panel, so that the fingerprint recognition function can be implemented in the display area. However, due to the unstable threshold voltage of the current photoelectric detection circuit, the circuit noise is large and the signal-to-noise ratio (SNR) is relatively low (for example, at a four-fold gain, the SNR is 12.6 dB), resulting in a relatively blurred fingerprint picture and reducing the accuracy of fingerprint recognition.

[0055] As Figure 1 shown, the photoelectric detection circuit provided by an embodiment of this disclosure includes:

[0056] A photoelectric conversion device 10, configured to convert a received optical signal into an electrical signal;

[0057] A drive control circuit 20, coupled to the photoelectric conversion device 10, configured to generate a detection current according to the signal of the detection control signal terminal CS and the electrical signal converted by the photoelectric conversion device 10;

[0058] An output control circuit 30, coupled to the drive control circuit 20, configured to output the detection current to the detection terminal VO in response to the signal of the detection scan signal terminal GA.

[0059] The photoelectric detection circuit provided by an embodiment of this disclosure, through the mutual cooperation of the drive control circuit and the output control circuit, can generate an amplified detection current according to the electrical signal converted by the photoelectric conversion device, thereby improving the clarity of the obtained fingerprint picture and further improving the accuracy of fingerprint recognition.

[0060] In some embodiments of this disclosure, as Figure 2As shown, the drive control circuit 20 may include: a control circuit 21 and a drive circuit 22; wherein, the control circuit 21 is coupled to the first conversion electrode of the photoelectric conversion device 10, and the drive circuit is coupled to the first conversion electrode of the photoelectric conversion device 10. Moreover, the control circuit 21 is configured to pull down the voltage of the first conversion electrode in response to the signal of the detection control signal terminal CS. The drive circuit 22 is coupled to the first conversion electrode of the photoelectric conversion device 10 and is configured to perform threshold compensation in response to the signal of the detection compensation signal terminal RA and generate a detection current according to the electrical signal.

[0061] The photoelectric detection circuit provided by the embodiments of the present disclosure can achieve threshold compensation through the mutual cooperation of the control circuit, the drive circuit, and the output control circuit, avoiding the problem of large circuit noise caused by unstable threshold voltage, thereby improving the signal-to-noise ratio, enhancing the clarity of the obtained fingerprint image, and further improving the accuracy of fingerprint recognition.

[0062] In some embodiments of the present disclosure, as Figure 3 shown, the second conversion electrode of the photoelectric conversion device 10 is coupled to the second power supply terminal ELVSS. Exemplarily, the first conversion electrode may be the positive electrode, and the second conversion electrode may be the negative electrode. Exemplarily, the photoelectric conversion device 10 may be set as a photodiode. For example, Figure 3 shown, the photoelectric conversion device 10 may be set as an organic photodiode OPD. Especially for the organic photodiode, in the embodiments of the present disclosure, a control circuit and a drive circuit are provided, which can amplify the electrical signal converted by the organic photodiode and output it to the detection chip for fingerprint detection and recognition. Moreover, since the drive circuit can achieve threshold voltage compensation, avoiding the problem of large circuit noise caused by unstable threshold voltage, thereby improving the signal-to-noise ratio, enhancing the clarity of the obtained fingerprint image, and further improving the accuracy of fingerprint recognition.

[0063] In some embodiments of the present disclosure, as Figure 3 shown, the control circuit 21 may include: a capacitor C0; wherein, the first electrode plate of the capacitor C0 is coupled to the detection control signal terminal CS, and the second electrode plate of the capacitor C0 is coupled to the first conversion electrode.

[0064] In some embodiments of the present disclosure, as Figure 3As shown, the driving circuit 22 may include: a detection driving transistor M1 and a detection compensation transistor M2; wherein, the gate of the detection driving transistor M1 is coupled to the first conversion electrode, the first pole of the detection driving transistor M1 is coupled to the first power supply terminal VDD, and the second pole of the detection driving transistor M1 is coupled to the output control circuit 30. Further, the gate of the detection compensation transistor M2 is coupled to the detection compensation signal terminal RA, the first pole of the detection compensation transistor M2 is coupled to the first pole of the detection driving transistor M1, and the second pole of the detection compensation transistor M2 is coupled to the second pole of the detection driving transistor M1. Exemplarily, the detection driving transistor M1 may be set as a P-type transistor or an N-type transistor. The detection compensation transistor M2 may be set as a P-type transistor or an N-type transistor.

[0065] In some embodiments of the present disclosure, as Figure 3 shown, the output control circuit 30 may include: a detection scanning transistor M3; wherein, the gate of the detection scanning transistor M3 is coupled to the detection scanning signal terminal GA, the first pole of the detection scanning transistor M3 is coupled to the driving circuit, and the second pole of the detection scanning transistor M3 is coupled to the detection terminal VO. Exemplarily, the detection scanning transistor M3 may be set as a P-type transistor or an N-type transistor.

[0066] Furthermore, in specific implementation, in the embodiments of the present disclosure, the P-type transistor is cut off under the action of a high-level signal and conducts under the action of a low-level signal. The N-type transistor conducts under the action of a high-level signal and is cut off under the action of a low-level signal.

[0067] It should be noted that the transistors mentioned in the above embodiments of the present disclosure may be low-temperature poly-silicon (LTPS) transistors or metal-oxide semiconductor field-effect transistors (MOS), which are not limited herein.

[0068] It should be noted that in the embodiments of the present disclosure, as Figure 3 shown, the detection compensation transistor M2 may be set as an N-type transistor and set as a MOS transistor, so as to reduce the influence of leakage current on the gate voltage of the detection driving transistor M1. The detection driving transistor M1 and the detection scanning transistor M3 may be set as P-type transistors and both set as LTPS, so as to improve the mobility and can be made thinner, smaller, and lower in power consumption, etc. This can further improve the signal-to-noise ratio, improve the clarity of the obtained fingerprint image, and further improve the accuracy of fingerprint recognition.

[0069] In a specific implementation, according to the type of the transistor and the signal of its gate, the first pole of the transistor can be used as its source, and the second pole as its drain; or vice versa, the first pole of the transistor can be used as its drain, and the second pole as its source. This can be designed and determined according to the actual application environment, and no specific distinction is made here.

[0070] In a specific implementation, in the embodiments of the present disclosure, the voltage Vdd of the first power supply terminal VDD can be a positive value, and the voltage Vss of the second power supply terminal ELVSS can be a negative value (e.g., -2.4V). In actual applications, the specific values of the voltage Vdd of the first power supply terminal VDD and the voltage Vss of the second power supply terminal ELVSS can be designed and determined according to the actual application environment, and are not limited herein.

[0071] The embodiments of the present disclosure also provide a driving method for the above-mentioned photoelectric detection circuit, as Figure 4 shown, which may include the following steps:

[0072] S100, the first stage, a signal with a first voltage is loaded on the detection control signal terminal.

[0073] S200, the second stage, a signal with a second voltage is loaded on the detection control signal terminal. The photoelectric conversion device converts the received optical signal into an electrical signal. The driving control circuit receives the electrical signal and generates a detection current according to the electrical signal; the output control circuit responds to the signal on the detection scanning signal terminal and outputs the detection current to the detection terminal. Among them, the first voltage is greater than the second voltage.

[0074] In some embodiments of the present disclosure, the first stage may include: a reset compensation stage. Among them, in the reset compensation stage, a signal with a first level is loaded on the detection compensation signal terminal, a signal with a first level is loaded on the detection scanning signal line, and a signal with a first voltage is loaded on the detection control signal terminal.

[0075] In some embodiments of the present disclosure, the second stage may include: a conversion stage and an output stage. Among them, in the conversion stage, a signal with a second level can be loaded on the detection compensation signal terminal, a signal with a first level can be loaded on the detection scanning signal line, and a signal with a second voltage can be loaded on the detection control signal terminal. In the output stage, a signal with a second level can be loaded on the detection compensation signal terminal, a signal with a second level can be loaded on the detection scanning signal line, and a signal with a second voltage can be loaded on the detection control signal terminal.

[0076] In some embodiments of the present disclosure, the voltage value of the signal with the first level loaded on the detection control signal terminal is greater than the voltage value of the signal with the second level loaded on the detection control signal terminal. Exemplarily, there may be a formula: Vdd + Vth - (Vcs1 - Vcs2) < Vss, where Vth represents the threshold voltage of the detection driving transistor (for example, it can be -1.5V), Vcs1 represents the voltage value of the first voltage of the signal loaded on the detection control signal terminal, and Vcs2 represents the voltage value of the second voltage of the signal loaded on the detection control signal terminal. In practical applications, the specific voltage values of the above signals can be determined according to the requirements of practical applications, and are not limited herein.

[0077] Taking the Figure 3 driving circuit shown below as an example, in combination with the Figure 5 circuit timing diagram shown below, the working process of the above photoelectric detection circuit provided by the embodiments of the present disclosure will be described. As Figure 5 shown, ra represents the signal of the compensation scanning signal terminal, ga represents the signal of the detection scanning signal terminal GA, and cs represents the signal of the detection control signal terminal CS. Moreover, the working process of a photoelectric detection circuit 111 in a display frame F0 may include: a first stage T10 and a second stage T20. Among them, the first stage T10 includes a reset compensation stage T11. The second stage T20 includes a conversion stage T21 and an output stage T22.

[0078] In the reset compensation stage T11, the detection scanning transistor M3 is cut off under the control of the high-level signal of ga. The detection compensation transistor M2 is turned on under the control of the high-level signal of the signal ra, so that the detection driving transistor M1 can form a diode mode, thereby enabling the voltage Vdd of the first power supply terminal VDD to reset the gate and the second pole of the detection driving transistor M1, and making the voltage of the second electrode plate of the capacitor be Vdd. A signal cs with a first voltage Vcs1 is loaded on the detection control signal terminal CS, so that the voltage of the first electrode plate of the capacitor is the first voltage Vcs1. Since the voltage of the first conversion electrode of the organic photodiode OPD is higher than the voltage of the second conversion electrode, a forward current can be formed in the organic photodiode OPD.

[0079] In the conversion stage T21, the compensation transistor is turned off under the control of the low-level signal of signal ra. The detection scan transistor M3 is turned off under the control of the high-level signal of ga. A signal cs with a second voltage Vcs2 is loaded onto the detection control signal terminal CS, so that the voltage of the first electrode plate of the capacitor jumps from the first voltage Vcs1 to the second voltage Vcs2. Due to the effect of the capacitor, the voltage of the second electrode plate of the capacitor can jump from Vdd + Vth to Vdd + Vth - (Vcs1 - Vcs2). Since Vdd + Vth - (Vcs1 - Vcs2) < Vss, an inverse current can be generated in the organic optoelectronic diode OPD. When the organic optoelectronic diode OPD is illuminated, a photocurrent can be generated, and this photocurrent can flow into the gate of the detection driving transistor M1, so that the gate voltage of the detection driving transistor M1 changes to Vdd + Vth - (Vcs1 - Vcs2) + ΔV, so that the detection driving transistor M1 operates in the amplification region, thereby generating a detection current IS. And, IS = K[Vdd + Vth - (Vcs1 - Vcs2) + ΔV - Vdd - Vth] 2 = K[-(Vcs1 - Vcs2) + ΔV] 2 . Wherein, K represents the structural parameter of the detection driving transistor M1. ΔV represents the voltage formed after the photocurrent flows into the gate of the detection driving transistor M1.

[0080] In the output stage T22, the compensation transistor is turned off under the control of the low-level signal of signal ra. The detection scan transistor M3 is turned on under the control of the low-level signal of ga, so that the detection current IS can be output to the detection terminal VO.

[0081] It should be noted that, as can be seen from the formula satisfied by the detection current IS, the detection current IS is independent of the threshold voltage of the detection driving transistor M1, so that the problem of unclear fingerprint images caused by unstable threshold voltages can be avoided, and thus the accuracy of fingerprint detection and recognition can be improved.

[0082] The embodiment of the present disclosure also provides a display panel, including the above-mentioned optoelectronic detection circuit provided by the embodiment of the present disclosure. Exemplarily, as Figure 6 shown in Figure 7 , the display panel further includes a substrate 100, and a plurality of optoelectronic detection units 110 and a plurality of light-emitting sub-pixels SPX located in the display area of the substrate 100; wherein, the orthographic projection of the light-emitting sub-pixel SPX on the substrate 100 and the orthographic projection of the optoelectronic detection unit 110 on the substrate 100 do not overlap. And, the light-emitting sub-pixel SPX includes a light-emitting device, and the optoelectronic detection unit 110 includes an optoelectronic detection circuit 111. In this way, fingerprint detection and recognition can be realized in the display area of the display panel.

[0083] In some embodiments of the present disclosure, each sub-pixel may further include a driving circuit for driving the light-emitting device to emit light. Exemplarily, the first light-emitting electrode 2111 of the light-emitting device may be set as an anode, and the second light-emitting electrode 2112 may be set as a cathode. And, the light-emitting device further includes an organic light-emitting layer 2113 disposed between the first light-emitting electrode 2111 and the second light-emitting electrode 2112. Further, a hole transport layer and a hole injection layer may be included between the first light-emitting electrode 2111 and the organic light-emitting layer 2113, and an electron transport layer and an electron injection layer may be included between the second light-emitting electrode 2112 and the organic light-emitting layer 2113. Exemplarily, the light-emitting device may be set as an Organic Light Emitting Diode (OLED), a Quantum Dot Light Emitting Diodes (QLED), etc. And, generally, the driving circuit may include multiple transistors such as a light-emitting driving transistor and a switching transistor, as well as a storage capacitor, and its specific structure and working principle may be the same as those in the prior art, which will not be elaborated here.

[0084] In some embodiments of the present disclosure, as Figure 7 shown, the first conversion electrode 1111 of the photoelectric conversion device 10 may be set to be of the same layer and the same material as the first light-emitting electrode 2111 of the light-emitting device. In this way, there is no need to add additional preparation of the first conversion electrode 1111, and only through one patterning process, the patterns of the first conversion electrode 1111 and the first light-emitting electrode 2111 can be formed, which can simplify the preparation process, save production costs, and improve production efficiency. It should be noted that the first conversion electrodes are arranged at intervals from each other and the first light-emitting electrodes 2111 to avoid short circuit.

[0085] In some embodiments of the present disclosure, as Figure 7 shown, the second conversion electrode 1112 of the photoelectric conversion device 10 may be set to be of the same layer and the same material as the second light-emitting electrode 2112 of the light-emitting device. In this way, there is no need to add additional preparation of the second conversion electrode 1112, and only through one patterning process, the patterns of the second conversion electrode 1112 and the second light-emitting electrode 2112 can be formed, which can simplify the preparation process, save production costs, and improve production efficiency. Further, the second conversion electrodes and the second light-emitting electrodes 2112 may form an integral structure over the entire surface. That is, a conductive layer disposed over the entire surface serves both as the second light-emitting electrode 2112 and as the second conversion electrode.

[0086] In some embodiments of the present disclosure, as Figure 7As shown, the optoelectronic conversion device 10 may further include an organic optoelectronic conversion layer 1113 located between the first conversion electrode 1111 and the second conversion electrode 1112. Further, it may further include a hole transport layer and a hole injection layer located between the first conversion electrode 1111 and the organic optoelectronic conversion layer 1113, and an electron transport layer and an electron injection layer located between the second conversion electrode 1112 and the organic optoelectronic conversion layer 1113.

[0087] In some embodiments of the present disclosure, as Figure 7 shown, the gates of the transistors 1114 in the photodetector circuit 111 and the gates of the transistors 2114 in the driving circuit can be arranged on the same layer and made of the same material. In this way, there is no need to additionally prepare the gates of the transistors 1114 in the photodetector circuit 111. Only one lithography process is required to form the patterns of the gates of the transistors 2114 in the driving circuit and the gates of the transistors 1114 in the photodetector circuit 111, which can simplify the manufacturing process, save production costs, and improve production efficiency.

[0088] In some embodiments of the present disclosure, as Figure 7 shown, the active layers of the transistors 1114 in the photodetector circuit 111 and the active layers of the transistors 2114 in the driving circuit can be arranged on the same layer and made of the same material. In this way, there is no need to additionally prepare the active layers of the transistors 1114 in the photodetector circuit 111. Only one lithography process is required to form the patterns of the active layers of the transistors 2114 in the driving circuit and the active layers of the transistors 1114 in the photodetector circuit 111, which can simplify the manufacturing process, save production costs, and improve production efficiency. For example, the active layers of the transistors set as LTPS transistors in the electrical detection circuit are arranged on the same layer and made of the same material as the active layers of the transistors set as LTPS transistors in the driving circuit. The active layers of the transistors set as MOS transistors in the electrical detection circuit are arranged on the same layer and made of the same material as the active layers of the transistors set as MOS transistors in the driving circuit.

[0089] In some embodiments of the present disclosure, as Figure 7 shown, the source / drain electrodes of the transistors 1114 in the photodetector circuit 111 and the source / drain electrodes of the transistors 2114 in the driving circuit can be arranged on the same layer and made of the same material. In this way, there is no need to additionally prepare the source / drain electrodes of the transistors 1114 in the photodetector circuit 111. Only one lithography process is required to form the patterns of the source / drain electrodes of the transistors 2114 in the driving circuit and the source / drain electrodes of the transistors 1114 in the photodetector circuit 111, which can simplify the manufacturing process, save production costs, and improve production efficiency.

[0090] In some embodiments of the present disclosure, the display panel further includes: a plurality of detection control lines, a plurality of detection compensation lines, a plurality of detection scan lines, and a plurality of detection transmission lines. Among them, the detection control signal terminal of the photoelectric detection circuit in one row of photoelectric detection units is coupled to one detection control line, the detection compensation signal terminal of the photoelectric detection circuit in one row of photoelectric detection units is coupled to one detection compensation line, the detection scan signal terminal of the photoelectric detection circuit in one row of photoelectric detection units is coupled to one detection scan line, and the detection terminal of the photoelectric detection circuit in one column of photoelectric detection units is coupled to one detection transmission line.

[0091] Some embodiments of the present disclosure also provide some display devices, including the above-mentioned display panel provided by the embodiments of the present disclosure. The principle of the display device for solving problems is similar to that of the foregoing display panel. Therefore, the implementation of the display device can refer to the implementation of the foregoing display panel, and the repeated parts will not be elaborated here. In specific implementation, in the embodiments of the present disclosure, the display device may be: any product or component with a display function such as a mobile phone, a tablet computer, a television, a monitor, a laptop computer, a digital photo frame, a navigator, etc. Other essential components of the display device should be understood by those of ordinary skill in the art and will not be elaborated here, nor should they be regarded as a limitation to the present disclosure.

[0092] In some embodiments of the present disclosure, as Figure 8 shown, the display device further includes: a detection chip 200, and the detection chip 200 can be connected to the display panel in a bonding manner to achieve signal transmission between the detection chip 200 and the display panel. Exemplarily, the detection chip 200 can be first connected to the flexible circuit board 300 in a bonding manner, and then the flexible circuit board 300 is connected to the display panel in a bonding manner to achieve signal transmission between the detection chip 200 and the display panel.

[0093] In some embodiments of the present disclosure, as Figure 9 shown, the detection chip 200 may include a data processing circuit 210 and a plurality of signal transmission circuits 220; among them, the detection terminal VO of one column of photoelectric detection circuits 111 is coupled to one signal transmission circuit 220, and the signal transmission circuit 220 is configured to process the received detection current to obtain a target detection signal and send the target detection signal to the data processing circuit 210. The data processing circuit 210 is configured to perform fingerprint detection and recognition according to the target detection signal sent by the signal transmission circuit 220. Exemplarily, one signal transmission circuit 220 is coupled to the detection terminal VO of one column of photoelectric detection circuits 111 through one detection transmission line 120.

[0094] In some embodiments of the present disclosure, as Figure 10As shown, the signal transmission circuit 220 may include: a first amplifier OP1, a second amplifier OP2, a first switch K1, a first capacitor C1, a second capacitor C2, a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, and an analog-to-digital converter ADC. Among them, the first input terminal of the first amplifier OP1 is coupled to the corresponding detection transmission line 120, the second input terminal of the first amplifier OP1 is coupled to the initialization signal terminal Vinit, and the output terminal of the first amplifier OP1 is coupled to the first end of the first resistor R1. The second end of the first resistor R1 is coupled to the first end of the second resistor R2. The second end of the second resistor R2 is coupled to the first input terminal of the second amplifier OP2. The second input terminal of the second amplifier OP2 is coupled to the first end of the fourth resistor R4, the output terminal of the second amplifier OP2 is coupled to the input terminal of the analog-to-digital converter ADC, the output terminal of the analog-to-digital converter ADC is coupled to the data processing circuit 210. The second end of the fourth resistor R4 is coupled to the ground terminal. The first end of the third resistor R3 is coupled to the first input terminal of the second amplifier OP2, and the second end of the third resistor R3 is coupled to the input terminal of the analog-to-digital converter ADC. The first electrode plate of the first capacitor C1 is coupled to the first input terminal of the first amplifier OP1, and the second electrode plate of the first capacitor C1 is coupled to the output terminal of the first amplifier OP1. The first electrode plate of the second capacitor C2 is coupled to the second end of the first resistor R1, and the second electrode plate of the second capacitor C2 is coupled to the ground terminal. The first end of the first switch K1 is coupled to the first input terminal of the first amplifier OP1, and the second end of the first switch K1 is coupled to the output terminal of the first amplifier OP1.

[0095] Exemplarily, the detection current output on the detection transmission line 120 is input to the first input terminal of the first amplifier OP1. Then, through the mutual cooperation of the first amplifier OP1, the second amplifier OP2, the first switch K1, the first capacitor C1, the second capacitor C2, the first resistor R1, the second resistor R2, the third resistor R3, and the fourth resistor R4, the amplified detection current can be input to the input terminal of the analog-to-digital converter ADC, so that a corresponding analog voltage is generated at the input terminal of the analog-to-digital converter ADC. The analog-to-digital converter ADC can convert the generated analog voltage into a digital voltage and then input it to the data processing circuit 210. Thus, the data processing circuit 210 can obtain the digital voltage corresponding to each photoelectric detection unit 110, and further can determine the fingerprint image according to the digital voltage to achieve fingerprint detection and recognition.

[0096] Obviously, those skilled in the art can make various changes and modifications to the present disclosure without departing from the spirit and scope of the present disclosure. Thus, if these modifications and variations of the present disclosure fall within the scope of the claims of the present disclosure and their equivalent technologies, the present disclosure also intends to include these changes and modifications.

Claims

1. An optoelectronic detection circuit, characterized in that, Comprising: A photoelectric conversion device configured to convert a received optical signal into an electrical signal; A drive control circuit coupled to the photoelectric conversion device and configured to generate a detection current according to a signal at a detection control signal terminal and the electrical signal converted by the photoelectric conversion device; An output control circuit coupled to the drive control circuit and configured to output the detection current to a detection terminal in response to a signal at a detection scan signal terminal; Wherein, the drive control circuit includes: A control circuit coupled to a first conversion electrode of the photoelectric conversion device and configured to pull down the voltage of the first conversion electrode in response to a signal at the detection control signal terminal; A drive circuit coupled to the first conversion electrode of the photoelectric conversion device and configured to perform threshold compensation in response to a signal at a detection compensation signal terminal and generate a detection current according to the electrical signal; Wherein, the control circuit includes: a capacitor; A first electrode plate of the capacitor is coupled to the detection control signal terminal, and a second electrode plate of the capacitor is coupled to the first conversion electrode.

2. The optoelectronic detection circuit according to claim 1, characterized in that, The drive circuit includes: a detection drive transistor and a detection compensation transistor; A gate of the detection drive transistor is coupled to the first conversion electrode, a first pole of the detection drive transistor is coupled to a first power supply terminal, and a second pole of the detection drive transistor is coupled to the output control circuit; A gate of the detection compensation transistor is coupled to the detection compensation signal terminal, a first pole of the detection compensation transistor is coupled to the first pole of the detection drive transistor, and a second pole of the detection compensation transistor is coupled to the second pole of the detection drive transistor.

3. The optoelectronic detection circuit according to any one of claims 1-2, characterized in that, The output control circuit includes: a detection scan transistor; A gate of the detection scan transistor is coupled to the detection scan signal terminal, a first pole of the detection scan transistor is coupled to the drive circuit, and a second pole of the detection scan transistor is coupled to the detection terminal.

4. A display panel, characterized in that, Including the photoelectric detection circuit according to any one of claims 1-3.

5. The display panel according to claim 4, characterized in that, The display panel further includes a substrate, a plurality of photoelectric detection units and a plurality of light-emitting sub-pixels located in a display area of the substrate; wherein, a positive projection of the light-emitting sub-pixel on the substrate and a positive projection of the photoelectric detection unit on the substrate do not overlap; The light-emitting sub-pixel includes a light-emitting device; The photoelectric detection unit includes the photoelectric detection circuit.

6. The display panel according to claim 5, wherein The first conversion electrode of the photoelectric conversion device is provided with the same layer and the same material as the first light-emitting electrode of the light-emitting device; And / or, the second conversion electrode of the photoelectric conversion device is provided with the same layer and the same material as the second light-emitting electrode of the light-emitting device.

7. The display panel according to claim 6, characterized in that The light-emitting sub-pixel further includes a drive circuit for driving the light-emitting device to emit light; Gates of transistors in the photoelectric detection circuit and gates of transistors in the drive circuit are provided with the same layer and the same material; And / or, active layers of transistors in the photoelectric detection circuit and active layers of transistors in the drive circuit are provided with the same layer and the same material; And / or, source-drain electrodes of transistors in the photoelectric detection circuit and source-drain electrodes of transistors in the drive circuit are provided with the same layer and the same material.

8. A display device, characterized in that, including the display panel according to any one of claims 4-7.

9. The display device according to claim 8, wherein The display device further includes: a detection chip; wherein, the detection chip includes a data processing circuit and a plurality of signal transmission circuits; The detection ends of a column of the photoelectric detection circuits are coupled to one of the signal transmission circuits, and the signal transmission circuit is configured to process the received detection current to obtain a target detection signal and send the target detection signal to the data processing circuit; The data processing circuit is configured to perform fingerprint detection and identification according to the target detection signal sent by the signal transmission circuit.

10. A driving method for the optoelectronic detection circuit according to any one of claims 1-3, characterized in that, Including: In the first stage, a signal with a first voltage is loaded onto the detection control signal terminal; In the second stage, a signal with a second voltage is loaded onto the detection control signal terminal, the photoelectric conversion device converts the received optical signal into an electrical signal, the drive control circuit receives the electrical signal and generates a detection current according to the electrical signal; the output control circuit outputs the detection current to the detection end in response to the signal of the detection scan signal terminal; wherein, the first voltage is greater than the second voltage.

11. The driving method of the optoelectronic detection circuit according to claim 10, characterized in that, The first stage includes: A reset compensation stage, a signal with a first level is loaded onto the detection compensation signal terminal, a signal with a first level is loaded onto the detection scan signal terminal, and a signal with the first voltage is loaded onto the detection control signal terminal.

12. The driving method of the optoelectronic detection circuit according to claim 10, wherein The second stage includes: A conversion stage, a signal with a second level is loaded onto the detection compensation signal terminal, a signal with a first level is loaded onto the detection scan signal terminal, and a signal with the second voltage is loaded onto the detection control signal terminal; An output stage, a signal with a second level is loaded onto the detection compensation signal terminal, a signal with a second level is loaded onto the detection scan signal terminal, and a signal with the second voltage is loaded onto the detection control signal terminal.

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