Fingerprint detection control circuit, fingerprint detection control method and display device

Abstract

The present invention provides a fingerprint detection control circuit, a fingerprint detection control method and a display device. The fingerprint detection circuit includes a sensing circuit, a reset circuit, a control circuit and a conversion circuit; the control circuit provides a switch control signal to the control end of the reset circuit under the control of a first control signal; the reset circuit provides a reset voltage to the conversion control end under the control of the potential of its control end; the conversion circuit controls the conversion of the photovoltage signal to a corresponding current signal when the first voltage end is connected to the first signal output end under the control of the potential of the conversion control end, and outputs the current signal through the first signal output end. The present invention can extend the validity period of fingerprint identification.

Description

Technical Field

[0001] The present invention relates to the field of fingerprint detection technology, and in particular to a fingerprint detection control circuit, a fingerprint detection control method and a display device. Background Art

[0002] In recent years, with the rapid development of technology, mobile products with biometric functions have gradually entered people's lives and work. Fingerprint technology has attracted much attention due to its unique identity characteristics. However, the fingerprint recognition of related optical fingerprint detection control circuits has a short validity period. Summary of the invention

[0003] The main purpose of the present invention is to provide a fingerprint detection control circuit, a fingerprint detection control method and a display device, so as to solve the problem in the prior art that in the discharge stage after the fingerprint recognition stage, the conversion transistor included in the conversion circuit is still turned on, resulting in the drift of the conversion transistor characteristics, thereby shortening the fingerprint recognition validity period.

[0004] In one aspect, an embodiment of the present invention provides a fingerprint detection circuit, including a sensing circuit, a reset circuit, a control circuit and a conversion circuit, wherein:

[0005] The sensing circuit is electrically connected to the conversion control terminal and is configured to convert the received optical signal into an optical voltage signal and provide the optical voltage signal to the conversion control terminal;

[0006] The control circuit is electrically connected to the first control line, the switch control signal terminal and the control terminal of the reset circuit respectively, and is configured to provide the switch control signal provided by the switch control signal terminal to the control terminal of the reset circuit under the control of the first control signal on the first control line;

[0007] The control terminal of the reset circuit is electrically connected to the reset control voltage terminal, and the reset circuit is electrically connected to the reset voltage terminal and the conversion control terminal respectively, and is configured to provide the reset voltage provided by the reset voltage terminal to the conversion control terminal under the control of the potential of the control terminal of the reset circuit;

[0008] The control end of the conversion circuit is electrically connected to the conversion control end, and the conversion circuit is also electrically connected to the first voltage end and the first signal output end respectively. Under the control of the potential of the conversion control end, the conversion circuit controls the connection or disconnection between the first voltage end and the first signal output end, and when the first voltage end and the first signal output end are connected, the photovoltage signal is converted into a corresponding current signal, and the current signal is output through the first signal output end.

[0009] Optionally, the fingerprint detection circuit described in at least one embodiment of the present invention further includes an output circuit;

[0010] The output circuit is electrically connected to the output control terminal, the first signal output terminal and the second signal output terminal respectively, and is configured to control the connection or disconnection between the first signal output terminal and the second signal output terminal under the control of the output control signal provided by the output control terminal.

[0011] Optionally, the sensing circuit includes a photoelectric conversion subcircuit and an energy storage subcircuit connected in parallel with each other; a first end of the photoelectric conversion subcircuit and a first end of the energy storage subcircuit are both electrically connected to the bias voltage end, and a second end of the photoelectric conversion subcircuit and a second end of the energy storage subcircuit are both electrically connected to the conversion control end;

[0012] The photoelectric conversion subcircuit is configured to convert the received optical signal into a photocurrent signal, and charge or discharge the energy storage subcircuit through the photocurrent signal to change the potential of the conversion control terminal accordingly.

[0013] Optionally, the control circuit includes a control transistor;

[0014] The control electrode of the control transistor is electrically connected to the first control line, the first electrode of the control transistor is electrically connected to the switch control signal terminal, and the second electrode of the control transistor is electrically connected to the control terminal of the reset circuit;

[0015] The switch control signal terminal is configured to provide the switch control signal.

[0016] Optionally, the reset circuit includes a reset transistor;

[0017] The control electrode of the reset transistor is electrically connected to the control end of the reset circuit, the first electrode of the reset transistor is electrically connected to the reset voltage end, and the second electrode of the reset transistor is electrically connected to the conversion control end.

[0018] Optionally, the conversion circuit includes a conversion transistor;

[0019] The control electrode of the conversion transistor is electrically connected to the conversion control terminal, the first electrode of the conversion transistor is electrically connected to the first voltage terminal, and the second electrode of the conversion transistor is electrically connected to the first signal output terminal.

[0020] Optionally, the output circuit includes an output transistor;

[0021] The control electrode of the output transistor is electrically connected to the output control terminal, the first electrode of the output transistor is electrically connected to the first signal output terminal, and the second electrode of the output transistor is electrically connected to the second signal output terminal.

[0022] Optionally, the photoelectric conversion subcircuit includes a photodiode, and the energy storage subcircuit includes a storage capacitor;

[0023] The anode of the photodiode is electrically connected to the bias voltage terminal, and the cathode of the photodiode is electrically connected to the conversion control terminal;

[0024] The first end of the storage capacitor is electrically connected to the bias voltage end, and the second end of the storage capacitor is electrically connected to the conversion control end.

[0025] In a second aspect, an embodiment of the present invention further provides a fingerprint detection control method, which is applied to the above-mentioned fingerprint detection circuit, and the fingerprint detection control method includes:

[0026] In the discharge stage, the control circuit provides a switch control signal to the control end of the reset circuit under the control of the first control signal on the first control line, and the reset circuit provides a reset voltage to the conversion control end under the control of the potential of its control end, so that the conversion circuit controls the disconnection between the first voltage end and the first signal output end under the control of the potential of the conversion control end.

[0027] Optionally, the discharging stage is arranged after the fingerprint detecting stage.

[0028] Optionally, the sensing circuit includes a photodiode and a storage capacitor connected in parallel with each other; and the fingerprint detection control method further includes:

[0029] In the discharge phase, the bias voltage provided by the bias voltage terminal is controlled so that the potential of the anode of the photodiode is equal to the potential of the cathode of the photodiode.

[0030] Optionally, the fingerprint detection circuit further includes an output circuit; the fingerprint detection stage includes a reset time period, a photoelectric conversion time period and a reading time period which are sequentially arranged, and the discharge stage is arranged after the reading time period; the fingerprint detection control method includes:

[0031] In the fingerprint detection stage, the control circuit disconnects the switch control signal terminal from the control terminal of the reset circuit under the control of the first control signal;

[0032] In the reset time period, the reset circuit provides the reset voltage provided by the reset voltage terminal to the conversion control terminal under the control of the reset control voltage provided by the reset control voltage terminal;

[0033] In the photoelectric conversion time period, the reset circuit stops providing the reset voltage to the conversion control terminal under the control of the reset control voltage, and the sensing circuit converts the received optical signal into a photovoltage signal and provides the photovoltage signal to the conversion control terminal;

[0034] During the reading time period, the conversion circuit, under the control of the potential of the conversion control terminal, controls the connection between the first voltage terminal and the first signal output terminal, converts the photovoltage signal into a corresponding current signal, and outputs the current signal through the first signal output terminal; the output circuit, under the control of the output control signal, controls the connection between the first signal output terminal and the second signal output terminal, so as to output the current signal through the second signal output terminal.

[0035] In a third aspect, an embodiment of the present invention further provides a display device, comprising the above-mentioned fingerprint detection circuit.

[0036] The fingerprint detection control circuit, fingerprint detection control method and display device described in the embodiments of the present invention adopt a control circuit. In the discharge stage, the control circuit provides a switch control signal to the control end of the reset circuit under the control of a first control signal. The reset circuit provides a reset voltage to the conversion control end under the control of the potential of its control end, so that the conversion circuit includes a conversion transistor that is not turned on, so that when fingerprint detection is not performed, the conversion transistor will not be turned on, thereby preventing the conversion transistor characteristics from drifting, ensuring the performance of the conversion transistor, and extending the validity period of fingerprint recognition. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 is a structural diagram of a fingerprint detection circuit according to at least one embodiment of the present invention;

[0038] Figure 2 is a structural diagram of a fingerprint detection circuit according to at least one embodiment of the present invention;

[0039] Figure 3 is a structural diagram of a fingerprint detection circuit according to at least one embodiment of the present invention;

[0040] Figure 4 is a circuit diagram of at least one embodiment of the fingerprint detection circuit of the present invention;

[0041] Figure 5 Yes Figure 4 FIG. 1 is a timing diagram showing the operation of at least one embodiment of the fingerprint detection circuit according to the present invention. DETAILED DESCRIPTION

[0042] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0043] The transistors used in all embodiments of the present invention may be triodes, thin film transistors, field effect transistors or other devices with the same characteristics. In the embodiments of the present invention, in order to distinguish the two electrodes of the transistor except the control electrode, one of the electrodes is called the first electrode and the other is called the second electrode.

[0044] In actual operation, when the transistor is a triode, the control electrode may be a base, the first electrode may be a collector, and the second electrode may be an emitter; or, the control electrode may be a base, the first electrode may be an emitter, and the second electrode may be a collector.

[0045] In actual operation, when the transistor is a thin film transistor or a field effect transistor, the control electrode can be a gate, the first electrode can be a drain, and the second electrode can be a source; or, the control electrode can be a gate, the first electrode can be a source, and the second electrode can be a drain.

[0046] The fingerprint detection circuit according to at least one embodiment of the present invention comprises a sensing circuit 11, a reset circuit 12, a control circuit 13 and a conversion circuit 14, wherein:

[0047] The sensing circuit 11 is electrically connected to the conversion control terminal Z0, and is configured to convert the received optical signal into an optical voltage signal, and provide the optical voltage signal to the conversion control terminal Z0;

[0048] The control circuit 13 is electrically connected to the first control line S1, the switch control signal terminal K0 and the control terminal of the reset circuit 12 respectively, and is configured to provide the switch control signal provided by the switch control signal terminal K0 to the control terminal of the reset circuit 12 under the control of the first control signal on the first control line S1;

[0049] The control terminal of the reset circuit 12 is electrically connected to the reset control voltage terminal D1, and the reset circuit 12 is electrically connected to the reset voltage terminal V0 and the conversion control terminal Z0 respectively, and is configured to provide the reset voltage provided by the reset voltage terminal V0 to the conversion control terminal Z0 under the control of the potential of the control terminal of the reset circuit 12;

[0050] The control end of the conversion circuit 14 is electrically connected to the conversion control end Z0, and the conversion circuit 14 is also electrically connected to the first voltage end V1 and the first signal output end O1, respectively. Under the control of the potential of the conversion control end Z0, the conversion circuit 14 controls the connection or disconnection between the first voltage end V1 and the first signal output end O1, and when the first voltage end V1 and the first signal output end O1 are connected, the photovoltage signal is converted into a corresponding current signal, and the current signal is output through the first signal output end O1.

[0051] The fingerprint detection circuit described in at least one embodiment of the present invention adopts a control circuit 13. In the discharge stage, the control circuit 13 provides a switch control signal to the control end of the reset circuit 12 under the control of a first control signal. The reset circuit 12 provides a reset voltage to the conversion control end Z0 under the control of the potential of its control end, so that the conversion circuit 14 controls the disconnection between the first voltage end V1 and the first signal output end O1 under the control of the potential of the conversion control end Z0, so that when fingerprint detection is not performed, the conversion transistor included in the conversion circuit 14 will not be turned on, thereby preventing the conversion transistor characteristics from drifting, ensuring the performance of the conversion transistor, and extending the validity period of fingerprint recognition.

[0052] Furthermore, when the fingerprint recognition circuit described in at least one embodiment of the present invention is working, the sensing circuit may include a photodiode and a storage capacitor connected in parallel with each other; in the discharge stage, the bias voltage provided by the bias voltage terminal may be controlled so that the potential of the anode of the photodiode is equal to the potential of the cathode of the photodiode, so that the photodiode does not work, thereby ensuring the performance of the photodiode and extending the validity period of fingerprint recognition.

[0053] like Figure 2 As shown, in Figure 1 Based on the embodiment of the fingerprint detection circuit shown, the fingerprint detection circuit according to at least one embodiment of the present invention further includes an output circuit 20;

[0054] The output circuit 20 is electrically connected to the output control terminal D2, the first signal output terminal O1 and the second signal output terminal O2 respectively, and is configured to control the connection or disconnection between the first signal output terminal O1 and the second signal output terminal O2 under the control of the output control signal provided by the output control terminal D2.

[0055] The present invention Figure 2 When at least one embodiment of the fingerprint detection circuit shown is in operation, the fingerprint detection phase may include a reset time period, a photoelectric conversion time period and a reading time period which are arranged in sequence, and the discharge phase may be arranged after the reading time period;

[0056] In the fingerprint detection stage, the control circuit 13, under the control of the first control signal, disconnects the switch control signal terminal K0 from the control terminal of the reset circuit 12, and stops providing the switch control signal to the control terminal of the reset circuit 12;

[0057] In the reset time period, the reset circuit 12 provides the reset voltage provided by the reset voltage terminal V0 to the conversion control terminal Z0 under the control of the reset control voltage provided by the reset control voltage terminal D1;

[0058] In the photoelectric conversion period, the reset circuit 12 stops providing the reset voltage to the conversion control terminal Z0 under the control of the reset control voltage, and the sensing circuit 11 is configured to convert the received optical signal into a photovoltage signal and provide the photovoltage signal to the conversion control terminal Z0;

[0059] During the reading time period, the conversion circuit 14, under the control of the potential of the conversion control terminal Z0, controls the connection between the first voltage terminal V1 and the first signal output terminal O1, converts the photovoltage signal into a corresponding current signal, and outputs the current signal through the first signal output terminal O1; the output circuit 20, under the control of the output control signal, controls the connection between the first signal output terminal O1 and the second signal output terminal O2, so as to output the current signal through the second signal output terminal O2.

[0060] like Figure 3 As shown, in Figure 2 Based on the embodiment of the fingerprint detection circuit shown, the sensing circuit 11 may include a photoelectric conversion subcircuit 30 and an energy storage subcircuit 31 connected in parallel with each other;

[0061] The first end of the photoelectric conversion subcircuit 30 and the first end of the energy storage subcircuit 31 are both electrically connected to the bias voltage terminal V2, and the second end of the photoelectric conversion subcircuit 30 and the second end of the energy storage subcircuit 31 are both electrically connected to the conversion control terminal Z0;

[0062] The photoelectric conversion subcircuit 30 is configured to convert the received optical signal into a photocurrent signal, and charge or discharge the energy storage subcircuit 31 through the photocurrent signal to change the potential of the conversion control terminal Z0 accordingly.

[0063] In at least one embodiment of the present invention, the sensing circuit 11 may include a photoelectric conversion sub-circuit 30 and an energy storage sub-circuit 31 connected in parallel. The photoelectric conversion sub-circuit 30 converts the received light signal into a photocurrent signal, and charges and discharges the energy storage sub-circuit 31 through the photocurrent signal to change the potential of the conversion control terminal Z0.

[0064] Optionally, the control circuit includes a control transistor;

[0065] The control electrode of the control transistor is electrically connected to the first control line, the first electrode of the control transistor is electrically connected to the switch control signal terminal, and the second electrode of the control transistor is electrically connected to the control terminal of the reset circuit;

[0066] The switch control signal terminal is configured to provide the switch control signal.

[0067] Optionally, the reset circuit includes a reset transistor;

[0068] The control electrode of the reset transistor is electrically connected to the control end of the reset circuit, the first electrode of the reset transistor is electrically connected to the reset voltage end, and the second electrode of the reset transistor is electrically connected to the conversion control end.

[0069] In at least one embodiment of the present invention, the conversion circuit includes a conversion transistor;

[0070] The control electrode of the conversion transistor is electrically connected to the conversion control terminal, the first electrode of the conversion transistor is electrically connected to the first voltage terminal, and the second electrode of the conversion transistor is electrically connected to the first signal output terminal.

[0071] Optionally, the output circuit includes an output transistor;

[0072] The control electrode of the output transistor is electrically connected to the output control terminal, the first electrode of the output transistor is electrically connected to the first signal output terminal, and the second electrode of the output transistor is electrically connected to the second signal output terminal.

[0073] In a specific implementation, the photoelectric conversion subcircuit may include a photodiode, and the energy storage subcircuit may include a storage capacitor;

[0074] The anode of the photodiode is electrically connected to the bias voltage terminal, and the cathode of the photodiode is electrically connected to the conversion control terminal;

[0075] The first end of the storage capacitor is electrically connected to the bias voltage end, and the second end of the storage capacitor is electrically connected to the conversion control end.

[0076] like Figure 4 As shown, the fingerprint detection circuit according to at least one embodiment of the present invention includes a sensor circuit, a reset circuit 12, a control circuit 13, a conversion circuit 14 and an output circuit 20, wherein:

[0077] The sensing circuit includes a photoelectric conversion subcircuit 30 and an energy storage subcircuit 31 connected in parallel with each other;

[0078] The control circuit 13 includes a control transistor T4; the reset circuit 12 includes a reset transistor T3;

[0079] The gate of the control transistor T4 is electrically connected to the first control line S1, the source of the control transistor T4 is electrically connected to the switch control signal terminal K0, and the drain of the control transistor T4 is electrically connected to the gate of the reset transistor T3;

[0080] The switch control signal terminal K0 is configured to provide the switch control signal;

[0081] The gate of the reset transistor T3 is electrically connected to the reset control voltage terminal D1, the source of the reset transistor T3 is electrically connected to the reset voltage terminal V0, and the drain of the reset transistor T3 is electrically connected to the conversion control terminal Z0;

[0082] The conversion circuit 14 includes a conversion transistor T2;

[0083] The gate of the conversion transistor T2 is electrically connected to the conversion control terminal Z0, the source of the conversion transistor T2 is electrically connected to the first voltage terminal V1, and the drain of the conversion transistor T2 is electrically connected to the first signal output terminal O1;

[0084] The output circuit 20 includes an output transistor T1;

[0085] The gate of the output transistor T1 is electrically connected to the output control terminal D2, the source of the output transistor T1 is electrically connected to the first signal output terminal O1, and the drain of the output transistor T1 is electrically connected to the second signal output terminal O2;

[0086] The photoelectric conversion subcircuit 30 includes a photodiode P1, and the energy storage subcircuit 31 includes a storage capacitor C1;

[0087] The anode of the photodiode P1 is electrically connected to the bias voltage terminal V2, and the cathode of the photodiode P1 is electrically connected to the conversion control terminal Z0;

[0088] A first end of the storage capacitor C1 is electrically connected to the bias voltage terminal V2 , and a second end of the storage capacitor C1 is electrically connected to the conversion control terminal Z0 .

[0089] In the present invention, Figure 4 In at least one embodiment of the fingerprint detection circuit shown, all transistors are n-type thin film transistors, but the present invention is not limited thereto.

[0090] In the present invention, Figure 4In at least one embodiment of the fingerprint detection circuit shown, the switch control signal terminal K0 can provide a high voltage signal, and the first voltage terminal V1 can provide a high voltage signal, but the present invention is not limited thereto.

[0091] like Figure 5 As shown, the present invention is Figure 4 At least one embodiment of the fingerprint detection circuit shown in FIG. 1 is in operation.

[0092] The fingerprint detection stage includes a reset time period t1, a photoelectric conversion time period t2 and a reading time period t3 which are arranged in sequence, and a discharge stage t0 is arranged after the fingerprint detection stage;

[0093] In the reset time period t1, the reset control voltage terminal D1 provides a high voltage signal, D2 provides a low voltage signal, V0 provides a high voltage signal, S1 provides a low voltage signal, T3 is turned on, T4 is turned off, and the high voltage signal provided by V0 is written into Z0. At this time, the potential of Z0 is greater than the potential of the voltage signal provided by V2, so that P1 is in a reverse bias state, so that P1 can perform photoelectric conversion at the beginning of the photoelectric conversion time period t2; T1 is turned off, and O2 outputs a low voltage;

[0094] In the photoelectric conversion time period t2, D1 provides a low voltage signal, D2 provides a low voltage signal, V0 provides a high voltage signal, S1 provides a low voltage signal, T4 is turned off, T3 is turned off, and the reset voltage is stopped from being provided to the conversion control terminal Z0, and P1 converts the received optical signal into a corresponding photocurrent, and the photocurrent flows from the cathode of P1 to the anode of P1 to discharge C1 and reduce the potential of Z0; T1 is turned off, and O2 continues to output a low voltage; in the photoelectric conversion time period t2, the voltage signal of Z0 is the photovoltage signal obtained by conversion;

[0095] In the reading time period t3, D1 provides a low voltage signal, D2 provides a high voltage signal, S1 provides a low voltage signal, T4 is turned off, T3 is turned off, T1 is turned on, T2 converts the photovoltage signal into a corresponding current signal, and outputs the current signal through O2;

[0096] In the discharge stage t0, D1 provides a low voltage signal, D2 provides a low voltage signal, S1 provides a high voltage signal, K0 provides a high voltage signal, T4 is turned on to provide the high voltage signal provided by K0 to the gate of T3 to control T3 to turn on, V0 provides a low voltage signal to provide the low voltage signal provided by V0 to Z0 to control T2 to turn off, so that in the discharge stage t0, the characteristics of T2 will not drift; and at this time V2 provides a low voltage signal to make the potential of the anode of P1 equal to the potential of the cathode of P1, so that P1 does not work, thereby ensuring the performance of P1.

[0097] The fingerprint detection control method according to at least one embodiment of the present invention is applied to the above-mentioned fingerprint detection circuit, and the fingerprint detection control method includes:

[0098] In the discharge stage, the control circuit provides a switch control signal to the control end of the reset circuit under the control of the first control signal on the first control line, and the reset circuit provides a reset voltage to the conversion control end under the control of the potential of its control end, so that the conversion circuit controls the disconnection between the first voltage end and the first signal output end under the control of the potential of the conversion control end.

[0099] In the fingerprint detection control method described in at least one embodiment of the present invention, in the discharge stage, the control circuit provides a switch control signal to the control end of the reset circuit under the control of the first control signal, and the reset circuit provides a reset voltage to the conversion control end under the control of the potential of its control end, so that the conversion circuit includes a conversion transistor that is not turned on, so that when fingerprint detection is not performed, the conversion transistor will not be turned on, thereby preventing the conversion transistor characteristics from drifting, ensuring the performance of the conversion transistor, and extending the validity period of fingerprint recognition.

[0100] Optionally, the discharge phase may be arranged after the fingerprint detection phase, but is not limited thereto.

[0101] In a specific implementation, the sensing circuit includes a photodiode and a storage capacitor connected in parallel with each other; the fingerprint detection control method also includes:

[0102] In the discharge phase, the bias voltage provided by the bias voltage terminal is controlled so that the potential of the anode of the photodiode is equal to the potential of the cathode of the photodiode.

[0103] In a specific implementation, the sensing circuit may include a photodiode and a storage capacitor connected in parallel with each other; in the discharge stage, the bias voltage provided by the bias voltage terminal may be controlled so that the potential of the anode of the photodiode is equal to the potential of the cathode of the photodiode, so that the photodiode does not work, thereby ensuring the performance of the photodiode and extending the validity period of fingerprint recognition.

[0104] In at least one embodiment of the present invention, the fingerprint detection circuit may further include an output circuit; the fingerprint detection stage includes a reset time period, a photoelectric conversion time period and a reading time period which are sequentially arranged, and the discharge stage is arranged after the reading time period; the fingerprint detection control method includes:

[0105] In the fingerprint detection stage, the control circuit disconnects the switch control signal terminal from the control terminal of the reset circuit under the control of the first control signal;

[0106] In the reset time period, the reset circuit provides the reset voltage provided by the reset voltage terminal to the conversion control terminal under the control of the reset control voltage provided by the reset control voltage terminal;

[0107] In the photoelectric conversion time period, the reset circuit stops providing the reset voltage to the conversion control terminal under the control of the reset control voltage, and the sensing circuit converts the received optical signal into a photovoltage signal and provides the photovoltage signal to the conversion control terminal;

[0108] During the reading time period, the conversion circuit, under the control of the potential of the conversion control terminal, controls the connection between the first voltage terminal and the first signal output terminal, converts the photovoltage signal into a corresponding current signal, and outputs the current signal through the first signal output terminal; the output circuit, under the control of the output control signal, controls the connection between the first signal output terminal and the second signal output terminal, so as to output the current signal through the second signal output terminal.

[0109] A display device according to at least one embodiment of the present invention includes the above-mentioned fingerprint detection circuit.

[0110] The display device provided in at least one embodiment of the present invention may be any product or component with a display function, such as a mobile phone, a tablet computer, a television, a monitor, a notebook computer, a digital photo frame, a navigator, or the like.

[0111] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A fingerprint detection circuit, characterized in that: It includes a sensing circuit, a reset circuit, a control circuit and a conversion circuit, wherein: The sensing circuit is electrically connected to the conversion control terminal and is configured to convert the received optical signal into an optical voltage signal and provide the optical voltage signal to the conversion control terminal; The control circuit is electrically connected to the first control line, the switch control signal terminal and the control terminal of the reset circuit respectively, and is configured to provide the switch control signal provided by the switch control signal terminal to the control terminal of the reset circuit under the control of the first control signal on the first control line; The control terminal of the reset circuit is electrically connected to the reset control voltage terminal, and the reset circuit is electrically connected to the reset voltage terminal and the conversion control terminal respectively, and is configured to provide the reset voltage provided by the reset voltage terminal to the conversion control terminal under the control of the potential of the control terminal of the reset circuit; The control end of the conversion circuit is electrically connected to the conversion control end, and the conversion circuit is also electrically connected to the first voltage end and the first signal output end respectively. Under the control of the potential of the conversion control end, the conversion circuit controls the connection or disconnection between the first voltage end and the first signal output end, and when the first voltage end and the first signal output end are connected, the photovoltage signal is converted into a corresponding current signal, and the current signal is output through the first signal output end.

2. The fingerprint detection circuit according to claim 1, characterized in that: Also includes an output circuit; The output circuit is electrically connected to the output control terminal, the first signal output terminal and the second signal output terminal respectively, and is configured to control the connection or disconnection between the first signal output terminal and the second signal output terminal under the control of the output control signal provided by the output control terminal.

3. The fingerprint detection circuit according to claim 1 or 2, characterized in that: The sensing circuit comprises a photoelectric conversion subcircuit and an energy storage subcircuit connected in parallel with each other; a first end of the photoelectric conversion subcircuit and a first end of the energy storage subcircuit are both electrically connected to the bias voltage end, and a second end of the photoelectric conversion subcircuit and a second end of the energy storage subcircuit are both electrically connected to the conversion control end; The photoelectric conversion subcircuit is configured to convert the received optical signal into a photocurrent signal, and charge or discharge the energy storage subcircuit through the photocurrent signal to change the potential of the conversion control terminal accordingly.

4. The fingerprint detection circuit according to claim 1 or 2, characterized in that: The control circuit includes a control transistor; The control electrode of the control transistor is electrically connected to the first control line, the first electrode of the control transistor is electrically connected to the switch control signal terminal, and the second electrode of the control transistor is electrically connected to the control terminal of the reset circuit; The switch control signal terminal is configured to provide the switch control signal.

5. The fingerprint detection circuit according to claim 1 or 2, characterized in that: The reset circuit includes a reset transistor; The control electrode of the reset transistor is electrically connected to the control end of the reset circuit, the first electrode of the reset transistor is electrically connected to the reset voltage end, and the second electrode of the reset transistor is electrically connected to the conversion control end.

6. The fingerprint detection circuit according to claim 1 or 2, characterized in that: The conversion circuit includes a conversion transistor; The control electrode of the conversion transistor is electrically connected to the conversion control terminal, the first electrode of the conversion transistor is electrically connected to the first voltage terminal, and the second electrode of the conversion transistor is electrically connected to the first signal output terminal.

7. The fingerprint detection circuit as claimed in claim 2, characterized in that: The output circuit includes an output transistor; The control electrode of the output transistor is electrically connected to the output control terminal, the first electrode of the output transistor is electrically connected to the first signal output terminal, and the second electrode of the output transistor is electrically connected to the second signal output terminal.

8. The fingerprint detection circuit as claimed in claim 3, characterized in that: The photoelectric conversion subcircuit includes a photodiode, and the energy storage subcircuit includes a storage capacitor; The anode of the photodiode is electrically connected to the bias voltage terminal, and the cathode of the photodiode is electrically connected to the conversion control terminal; The first end of the storage capacitor is electrically connected to the bias voltage end, and the second end of the storage capacitor is electrically connected to the conversion control end.

9. A fingerprint detection control method, applied to the fingerprint detection circuit according to any one of claims 1 to 8, characterized in that: The fingerprint detection control method comprises: In the discharge stage, the control circuit provides a switch control signal to the control end of the reset circuit under the control of the first control signal on the first control line, and the reset circuit provides a reset voltage to the conversion control end under the control of the potential of its control end, so that the conversion circuit controls the disconnection between the first voltage end and the first signal output end under the control of the potential of the conversion control end.

10. The fingerprint detection control method according to claim 9, characterized in that: The discharge stage is arranged after the fingerprint detection stage.

11. The fingerprint detection control method according to claim 9 or 10, characterized in that: The sensing circuit includes a photodiode and a storage capacitor connected in parallel; the fingerprint detection control method also includes: In the discharge phase, the bias voltage provided by the bias voltage terminal is controlled so that the potential of the anode of the photodiode is equal to the potential of the cathode of the photodiode.

12. The fingerprint detection control method according to claim 9 or 10, characterized in that: The fingerprint detection circuit also includes an output circuit; the fingerprint detection stage includes a reset time period, a photoelectric conversion time period and a reading time period which are arranged in sequence, and the discharge stage is arranged after the reading time period; the fingerprint detection control method includes: In the fingerprint detection stage, the control circuit disconnects the switch control signal terminal from the control terminal of the reset circuit under the control of the first control signal; In the reset time period, the reset circuit provides the reset voltage provided by the reset voltage terminal to the conversion control terminal under the control of the reset control voltage provided by the reset control voltage terminal; In the photoelectric conversion time period, the reset circuit stops providing the reset voltage to the conversion control terminal under the control of the reset control voltage, and the sensing circuit converts the received optical signal into a photovoltage signal and provides the photovoltage signal to the conversion control terminal; During the reading time period, the conversion circuit, under the control of the potential of the conversion control terminal, controls the connection between the first voltage terminal and the first signal output terminal, converts the photovoltage signal into a corresponding current signal, and outputs the current signal through the first signal output terminal; the output circuit, under the control of the output control signal, controls the connection between the first signal output terminal and the second signal output terminal, so as to output the current signal through the second signal output terminal.

13. A display device, characterized in that: The method comprises a fingerprint detection circuit as claimed in any one of claims 1 to 8.

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