Photocurrent amplification circuit, amplification control method, light detection module and display device

Abstract

An optical current amplification circuit, an amplification control method, an optical detection module and a display device. The optical current amplification circuit has a threshold voltage compensation function, and the optical current amplification circuit comprises a photoelectric sensor (Dw), a compensation circuit (11), a reset circuit (12), an energy storage circuit (13) and a drive circuit (14). The photoelectric sensor (Dw) is used to sense the optical signal and convert the optical signal into the photoelectric current signal; the compensation circuit (11) controls the communication between the control end of the drive circuit (14) and the first end of the drive circuit (14) under the control of the compensation control signal; the reset circuit (12) controls the communication between the first voltage end and the control end of the drive circuit (14) under the control of the reset control signal; the drive circuit (14) generates the amplified photoelectric current signal flowing through the second end of the drive circuit (14) and the first end of the drive circuit (14) under the control of the potential of the control end. The photoelectric current signal converted by the photoelectric sensor (Dw) can be threshold voltage compensated and amplified, so that the external sampling circuit can collect the amplified photoelectric current signal.

Description

Technical Field

[0001] This disclosure relates to the field of optical detection technology, and in particular to a photocurrent amplification circuit, an amplification control method, an optical detection module, and a display device. Background Technology

[0002] With the widespread application of AI (Artificial Intelligence) technology in mobile display products, and the need to customize applications for specific environments based on the user's surroundings to enhance the user experience in different settings, it is essential to monitor the user's environment in real time. In existing ambient light detection modules, ambient light sensors can be fabricated on the display screen using the characteristics of TFTs (Thin Film Transistors). However, the photoelectric leakage current signal generated by the photoelectric sensor made of thin film is in the pA range. External sampling circuits struggle to sample and detect this leakage current signal, requiring amplification from the pA level to the nA or μA level. Summary of the Invention

[0003] The main objective of this disclosure is to provide a photocurrent amplification circuit, amplification control method, photodetector module, and display device to solve the problem in the prior art that it is not convenient to amplify the weak photocurrent signal generated by the photoelectric sensor, which makes signal sampling and detection inconvenient and also detrimental to the signal-to-noise ratio of the current signal on the detection channel.

[0004] In one aspect, embodiments of this disclosure provide a photocurrent amplification circuit, including a photoelectric sensor, a compensation circuit, a reset circuit, an energy storage circuit, and a driving circuit, wherein...

[0005] The photoelectric sensor is used to sense light signals, convert the light signals into photocurrent signals, and provide the photocurrent signals to the control terminal of the driving circuit;

[0006] The compensation circuit is electrically connected to the compensation control terminal, the control terminal of the drive circuit, and the first terminal of the drive circuit, respectively, and is used to control the connection between the control terminal of the drive circuit and the first terminal of the drive circuit under the control of the compensation control signal provided by the compensation control line;

[0007] The reset circuit is electrically connected to the reset control terminal, the first voltage terminal and the control terminal of the drive circuit, respectively, and is used to control the connection between the first voltage terminal and the control terminal of the drive circuit under the control of the reset control signal provided by the reset control terminal.

[0008] The first terminal of the energy storage circuit is electrically connected to the control terminal of the drive circuit, and the second terminal of the energy storage circuit is electrically connected to the second terminal of the drive circuit. The energy storage circuit is used to store electrical energy.

[0009] The second terminal of the driving circuit is electrically connected to the second voltage terminal. The driving circuit is used to generate an amplified photocurrent signal flowing through the second terminal and the first terminal of the driving circuit under the control of the potential of its control terminal.

[0010] Optionally, the photocurrent amplification circuit described in at least one embodiment of this disclosure further includes a sampling control circuit;

[0011] The sampling control circuit is electrically connected to the sampling control terminal, the first terminal of the driving circuit, and the sampling output terminal, respectively. Under the control of the sampling control signal provided by the sampling control terminal, it controls the connection between the first terminal of the driving circuit and the sampling output terminal so as to output the amplified photocurrent signal through the sampling output terminal.

[0012] Optionally, the compensation circuit includes a first transistor, and the reset circuit includes a second transistor;

[0013] The control electrode of the first transistor is electrically connected to the compensation control terminal, the first electrode of the first transistor is electrically connected to the control terminal of the driving circuit, and the second electrode of the first transistor is electrically connected to the first terminal of the driving circuit.

[0014] The control electrode of the second transistor is electrically connected to the reset control terminal, the first electrode of the second transistor is electrically connected to the first voltage terminal, and the second electrode of the second transistor is electrically connected to the control terminal of the drive circuit.

[0015] Optionally, the energy storage circuit includes a storage capacitor, and the driving circuit includes a driving transistor;

[0016] The control terminal of the driving transistor is the control terminal of the driving circuit, the first terminal of the driving transistor is the first terminal of the driving circuit, and the second terminal of the driving transistor is the second terminal of the driving circuit.

[0017] The first terminal of the storage capacitor is electrically connected to the control electrode of the driving transistor, and the second terminal of the storage capacitor is electrically connected to the second electrode of the driving transistor.

[0018] Optionally, the photoelectric sensor is a photodiode;

[0019] The anode of the photodiode is electrically connected to the first voltage terminal, and the cathode of the photodiode is electrically connected to the control terminal of the driving circuit.

[0020] Optionally, the sampling control circuit includes a third transistor;

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

[0022] In a second aspect, embodiments of this disclosure provide an amplification control method applied to the aforementioned photocurrent amplification circuit, wherein the operating cycle includes a reset phase, a compensation phase, a discharge phase, and a sampling phase arranged sequentially; the amplification control method includes:

[0023] During the reset phase, under the control of the reset control signal, the reset circuit writes the first voltage signal provided by the first voltage terminal into the control terminal of the drive circuit, so that at the beginning of the compensation phase, the drive circuit can control the connection between the first terminal and the second terminal of the drive circuit under the control of the potential of its control terminal.

[0024] During the compensation phase, under the control of the compensation control signal, the compensation circuit controls the connection between the control terminal of the drive circuit and the first terminal of the drive circuit.

[0025] At the start of the compensation phase, the driving circuit, under the control of the potential at its control terminal, controls the connection between the first terminal and the second terminal of the driving circuit to charge the energy storage circuit through the second voltage signal provided by the second voltage terminal, until the driving circuit disconnects the connection between its first terminal and the second terminal. The potential at the control terminal of the driving circuit is V2-Vth, where V2 is the voltage value of the second voltage signal and Vth is the absolute value of the threshold voltage of the driving transistor included in the driving circuit.

[0026] During the discharge phase, the photoelectric sensor senses the light signal and converts the light signal into a photocurrent signal. The photocurrent signal is used to discharge the energy storage circuit, thereby changing the potential of the control terminal of the drive circuit.

[0027] During the sampling phase, the driving circuit generates an amplified photocurrent signal flowing from the second terminal of the driving circuit to the first terminal of the driving circuit under the control of the potential of its control terminal, and outputs the amplified photocurrent signal through the first terminal of the driving circuit.

[0028] Optionally, the photoelectric sensor is a photodiode; the anode of the photodiode is electrically connected to the first voltage terminal, and the cathode of the photodiode is electrically connected to the control terminal of the driving circuit; the driving circuit includes a driving transistor.

[0029] VR = V2 - Vth - DV - V1; VR > 0;

[0030] Wherein, V1 is the voltage value of the first voltage signal, V2 is the voltage value of the second voltage signal, VR is the reverse bias voltage of the photodiode at the end of the discharge phase, Vth is the threshold voltage of the driving transistor, and DV is the change in potential at the control terminal of the driving circuit during the discharge phase.

[0031] Optionally, the photocurrent amplification circuit further includes a sampling control circuit; the amplification control method described in at least one embodiment of this disclosure further includes:

[0032] During the sampling phase, the sampling control circuit, under the control of the sampling control signal, controls the connection between the first terminal of the driving circuit and the sampling output terminal, so as to output the amplified photocurrent signal through the sampling output terminal.

[0033] In a third aspect, embodiments of this disclosure provide a light detection module, including the photocurrent amplification circuit, conversion circuit, and detection circuit described above;

[0034] The conversion circuit is electrically connected to the photocurrent amplifier circuit and is used to convert the amplified photocurrent signal output by the photocurrent amplifier circuit into an analog output voltage, and output the analog output voltage through the analog output voltage output terminal.

[0035] The detection circuit is used to obtain the characteristics of the optical signal sensed by the photoelectric sensor included in the photocurrent amplifier circuit based on the analog output voltage.

[0036] Optionally, the optical detection module described in at least one embodiment of this disclosure further includes a filtering circuit;

[0037] The filtering circuit is connected between the analog output voltage output terminal and the detection circuit, and is used to filter out high-frequency noise in the analog output voltage and provide the analog output voltage after filtering out high-frequency noise to the detection circuit.

[0038] The detection circuit is used to obtain the characteristics of the optical signal based on the analog output voltage after filtering out high-frequency noise.

[0039] Optionally, the detection circuit includes an analog-to-digital converter and an output processing unit;

[0040] The analog-to-digital converter is used to convert the analog output voltage into a digital output voltage; the output processing unit is electrically connected to the analog-to-digital converter and is used to receive the digital output voltage and obtain the characteristics of the optical signal based on the digital output voltage.

[0041] Optionally, the conversion circuit includes an operational amplifier, a sampling resistor, and a feedback capacitor; the photocurrent amplification circuit is used to output the amplified photocurrent signal through the sampling output terminal;

[0042] The non-inverting input terminal of the operational amplifier is electrically connected to the reference voltage terminal, the inverting input terminal of the operational amplifier is electrically connected to the sampling output terminal, and the output terminal of the operational amplifier is the analog output voltage output terminal.

[0043] The first end of the sampling resistor is electrically connected to the inverting input terminal of the operational amplifier, and the second end of the sampling resistor is electrically connected to the output terminal of the operational amplifier.

[0044] The first end of the feedback capacitor is electrically connected to the inverting input terminal of the operational amplifier, and the second end of the feedback capacitor is electrically connected to the output terminal of the operational amplifier.

[0045] In a fourth aspect, embodiments of this disclosure provide a display device including the light detection module described above.

[0046] Optionally, the photocurrent amplification circuit included in the light detection module is disposed on the display substrate, and the conversion circuit and the detection circuit included in the light detection module are both disposed on the circuit board or the display driver integrated circuit.

[0047] The photocurrent amplification circuit, amplification control method, photodetector module, and display device described in this embodiment of the invention can amplify the photocurrent signal converted by the photoelectric sensor for sampling and detection by external circuits, while improving the signal-to-noise ratio of the current signal on the detection channel. Attached Figure Description

[0048] Figure 1 This is a structural diagram of the photocurrent amplifier circuit described in the embodiments of this disclosure;

[0049] Figure 2 This is a structural diagram of the photocurrent amplifier circuit according to at least one embodiment of the present disclosure;

[0050] Figure 3 This is a circuit diagram of the photocurrent amplification circuit according to at least one embodiment of the present disclosure;

[0051] Figure 4 This is a public announcement. Figure 3 The timing diagram of at least one embodiment of the photocurrent amplifier circuit shown;

[0052] Figure 5 This is a structural diagram of the optical detection module described in the embodiments of this disclosure;

[0053] Figure 6 This is a structural diagram of the optical detection module according to at least one embodiment of the present disclosure;

[0054] Figure 7 This is a structural diagram of the optical detection module according to at least one embodiment of the present disclosure;

[0055] Figure 8 This is a structural diagram of the optical detection module according to at least one embodiment of the present disclosure;

[0056] Figure 9 This is a circuit diagram of the optical detection module according to at least one embodiment of the present disclosure;

[0057] Figure 10 This is a public announcement. Figure 9 The timing diagram of at least one embodiment of the optical detection module shown is a working diagram. Detailed Implementation

[0058] The technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. Based on the embodiments of this disclosure, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this disclosure.

[0059] In all embodiments of this disclosure, the transistors used can be bipolar junction transistors (BJTs), thin-film transistors (TFTs), field-effect transistors (FETs), or other devices with similar characteristics. In the embodiments of this disclosure, to distinguish the two terminals of the transistor other than the control terminal, one terminal is referred to as the first terminal and the other as the second terminal.

[0060] In actual operation, when the transistor is a thin-film transistor or a field-effect transistor, the first electrode can be the drain and the second electrode can be the source; or, the first electrode can be the source and the second electrode can be the drain.

[0061] like Figure 1 As shown, the photocurrent amplification circuit described in this embodiment includes a photoelectric sensor Dw, a compensation circuit 11, a reset circuit 12, an energy storage circuit 13, and a driving circuit 14, wherein...

[0062] The photoelectric sensor Dw is electrically connected to the control terminal of the driving circuit 14, and is used to sense light signals, convert the light signals into photocurrent signals, and provide the photocurrent signals to the control terminal of the driving circuit 14 and the first terminal of the energy storage circuit 13, thereby changing the potential of the first terminal of the energy storage circuit 13 through the photocurrent signals.

[0063] The compensation circuit 11 is electrically connected to the compensation control terminal S0, the control terminal of the driving circuit 14, and the first terminal of the driving circuit 14, respectively. It is used to control the connection between the control terminal of the driving circuit 14 and the first terminal of the driving circuit 14 under the control of the compensation control signal provided by the compensation control line S0, and to connect the driving transistors included in the driving circuit 14 into the form of diodes.

[0064] The reset circuit 12 is electrically connected to the reset control terminal R0, the first voltage terminal VT1 and the control terminal of the drive circuit 14 respectively, and is used to control the connection between the first voltage terminal VT1 and the control terminal of the drive circuit 14 under the control of the reset control signal provided by the reset control terminal R0.

[0065] The first end of the energy storage circuit 13 is electrically connected to the control end of the drive circuit 14, and the second end of the energy storage circuit 13 is electrically connected to the second end of the drive circuit 14. The energy storage circuit 13 is used to store electrical energy.

[0066] The second terminal of the driving circuit 14 is electrically connected to the second voltage terminal VT2. The driving circuit 14 is used to generate an amplified photocurrent signal flowing through the second terminal and the first terminal of the driving circuit 14 under the control of the potential of its control terminal.

[0067] In at least one embodiment of this disclosure, the photoelectric sensor may be a photodiode, and the photocurrent signal may be a photoleakage current signal, but is not limited thereto.

[0068] In at least one embodiment of this disclosure, the optical signal may be an ambient light signal, but is not limited thereto; in actual operation, the optical signal may also be an infrared light signal or other optical signals received by the photoelectric sensor.

[0069] In at least one embodiment of this disclosure, the driving circuit 14 may include a driving transistor. The driving circuit 14 generating an amplified photocurrent signal under the control of the potential of its control terminal means that when the potential of the control terminal of the driving circuit 14 changes to a level that enables the driving transistor included in the driving circuit 14 to conduct, the driving circuit 14 generates the amplified photocurrent signal.

[0070] Optionally, the first voltage terminal VT1 can be used to provide a low voltage, and the second voltage terminal VT2 can be used to provide a high voltage, but this is not a limitation.

[0071] In at least one embodiment of this disclosure, the voltage value V1 of the first voltage signal provided by the first voltage terminal VT1 can be around -1V; for example, V1 can be greater than or equal to -2V and less than or equal to 0V.

[0072] The voltage value V2 of the second voltage signal provided by the second voltage terminal VT2 can be around 5V. For example, V2 can be greater than or equal to 4V and less than or equal to 6V.

[0073] Vth can be around 2V; for example, Vth can be greater than 1.5V but less than 2.5V.

[0074] Wherein, Vth is the absolute value of the threshold voltage of the driving transistor.

[0075] The photocurrent amplification circuit described in this embodiment can amplify the pA-level photocurrent signal obtained by the photoelectric sensor to the nA or uA level for sampling and detection by external circuitry. By amplifying the photocurrent signal, the photocurrent amplification circuit described in this embodiment can improve the signal-to-noise ratio of the current signal on the detection channel.

[0076] In at least one embodiment of this disclosure, the external circuit may include Figure 9 The circuit includes a conversion circuit 41, a filter circuit 51, a digital-to-analog converter 61, and an output processing unit 62. The detection channel can be a channel for transmitting amplified photocurrent signals between the photocurrent amplification circuit 40 and the conversion circuit 41. In this embodiment, the amplified photocurrent signal is transmitted to the conversion circuit 41 through the detection channel, which can improve the signal-to-noise ratio of the current signal on the detection channel.

[0077] This disclosure Figure 1 The embodiment of the photocurrent amplifier circuit shown in the figure has a working cycle that includes a reset phase, a compensation phase, a discharge phase, and a sampling phase set sequentially.

[0078] During the reset phase, under the control of the reset control signal, the reset circuit 12 writes the first voltage signal provided by the first voltage terminal VT1 into the control terminal of the drive circuit 14, so that at the beginning of the compensation phase, the drive circuit 14 can control the first terminal of the drive circuit 14 to be connected to the second terminal of the drive circuit 14 under the control of the potential of its control terminal.

[0079] During the compensation phase, under the control of the compensation control signal, the compensation circuit 11 controls the connection between the control terminal of the drive circuit 14 and the first terminal of the drive circuit 14.

[0080] At the start of the compensation phase, under the control of the potential of its control terminal, the drive circuit 14 controls the connection between the first terminal and the second terminal of the drive circuit 14 to charge the energy storage circuit through the second voltage signal provided by the second voltage terminal VT2, until the drive circuit 14 disconnects the connection between its first terminal and the second terminal. The potential of the control terminal of the drive circuit 14 is V2-Vth, where V2 is the voltage value of the second voltage signal and Vth is the absolute value of the threshold voltage of the drive transistor included in the drive circuit 14.

[0081] During the discharge phase, the photoelectric sensor Dw senses the light signal and converts the light signal into a photocurrent signal. The photocurrent signal is used to discharge the energy storage circuit 13 and change the potential of the control terminal of the drive circuit 14.

[0082] During the sampling phase, the driving circuit 14 generates an amplified photocurrent signal flowing from the second terminal of the driving circuit 14 to the first terminal of the driving circuit 14 under the control of the potential of its control terminal, and outputs the amplified photocurrent signal through the first terminal of the driving circuit 14.

[0083] In at least one embodiment of this disclosure, V1, V2, and Vth need to be set to ensure that the photoelectric sensor Dw can perform photoelectric conversion throughout the entire discharge phase.

[0084] like Figure 2 As shown, in Figure 1 Based on the embodiment of the photocurrent amplifier circuit shown, the photocurrent amplifier circuit described in at least one embodiment of this disclosure may further include a sampling control circuit 21;

[0085] The sampling control circuit 21 is electrically connected to the sampling control terminal S1, the first terminal of the driving circuit 14, and the sampling output terminal Do, respectively. It is used to control the first terminal of the driving circuit 14 to connect with the sampling output terminal Do under the control of the sampling control signal provided by the sampling control terminal S1, so as to output the amplified photocurrent signal through the sampling output terminal Do.

[0086] This disclosure is as follows Figure 2 In at least one embodiment of the photocurrent amplification circuit shown, during the sampling phase, the sampling control circuit 21, under the control of the sampling control signal, controls the connection between the first terminal of the driving circuit 14 and the sampling output terminal Do, so as to output the amplified photocurrent signal through the sampling output terminal Do.

[0087] Optionally, the compensation circuit includes a first transistor, and the reset circuit includes a second transistor;

[0088] The control electrode of the first transistor is electrically connected to the compensation control terminal, the first electrode of the first transistor is electrically connected to the control terminal of the driving circuit, and the second electrode of the first transistor is electrically connected to the first terminal of the driving circuit.

[0089] The control electrode of the second transistor is electrically connected to the reset control terminal, the first electrode of the second transistor is electrically connected to the first voltage terminal, and the second electrode of the second transistor is electrically connected to the control terminal of the drive circuit.

[0090] Optionally, the energy storage circuit includes a storage capacitor, and the driving circuit includes a driving transistor;

[0091] The control terminal of the driving transistor is the control terminal of the driving circuit, the first terminal of the driving transistor is the first terminal of the driving circuit, and the second terminal of the driving transistor is the second terminal of the driving circuit.

[0092] The first terminal of the storage capacitor is electrically connected to the control electrode of the driving transistor, and the second terminal of the storage capacitor is electrically connected to the second electrode of the driving transistor.

[0093] Optionally, the photoelectric sensor is a photodiode;

[0094] The anode of the photodiode is electrically connected to the first voltage terminal, and the cathode of the photodiode is electrically connected to the control terminal of the driving circuit.

[0095] Optionally, the sampling control circuit includes a third transistor;

[0096] The control electrode of the third transistor is electrically connected to the sampling control terminal, the first electrode of the third transistor is electrically connected to the first terminal of the driving circuit, and the second electrode of the third transistor is electrically connected to the sampling output terminal.

[0097] like Figure 3 As shown, in Figure 2 Based on at least one embodiment of the photocurrent amplification circuit shown, the compensation circuit 11 includes a first transistor T1, the reset circuit 12 includes a second transistor T2, and the driving circuit 14 includes a driving transistor T0;

[0098] The gate of the first transistor T1 is electrically connected to the compensation control terminal S0, the drain of the first transistor T1 is electrically connected to the gate of the driving transistor T0, and the source of the first transistor T1 is electrically connected to the drain of the driving transistor T0.

[0099] The gate of the second transistor T2 is electrically connected to the reset control terminal R0, the drain of the second transistor T2 is electrically connected to the first voltage terminal VT1, and the source of the second transistor T2 is electrically connected to the gate of the driving transistor T0.

[0100] The energy storage circuit 13 includes a storage capacitor C1;

[0101] The first terminal of the storage capacitor C1 is electrically connected to the gate of the driving transistor T0, and the second terminal of the storage capacitor C1 is electrically connected to the source of the driving transistor T0.

[0102] The source of the driving transistor T0 is electrically connected to the second voltage terminal VT2;

[0103] The photoelectric sensor is a photodiode D1;

[0104] The anode of the photodiode D1 is electrically connected to the first voltage terminal VT1, and the cathode of the photodiode D1 is electrically connected to the gate of the driving transistor T0.

[0105] The sampling control circuit 21 includes a third transistor T3;

[0106] The gate of the third transistor T3 is electrically connected to the sampling control terminal S1, the source of the third transistor T3 is electrically connected to the source of the driving transistor T0, and the drain of the third transistor T3 is electrically connected to the sampling output terminal Do.

[0107] exist Figure 3 In at least one embodiment of the photocurrent amplifier circuit shown, the voltage value V1 of the first voltage signal provided by the first voltage terminal VT1 can be -1V, the voltage value V2 of the second voltage signal provided by the second voltage terminal VT2 can be 5V, and the absolute value Vth of the threshold voltage of the driving transistor T0 can be 2V, but is not limited thereto.

[0108] In actual operation, the voltage value V1 of the first voltage signal, the voltage value V2 of the second voltage signal, and the absolute value Vth of the threshold voltage of the driving transistor T0 can also be other values. The values ​​of V1, V2 and Vth need to satisfy the condition VR = V2 - Vth - DV - V1, and VR is greater than 0.

[0109] exist Figure 3 In at least one embodiment of the photocurrent amplifier circuit shown, all transistors are p-type thin-film transistors, but this is not a limitation.

[0110] This disclosure is as follows Figure 3 In at least one embodiment of the photocurrent amplifier circuit shown, in order to ensure that the photodiode D1 can continuously perform photoelectric conversion during the discharge phase, VR needs to be greater than 0, where VR = V2 - Vth - DV - V1; and VR is the reverse bias voltage of the photodiode D1 at the end of the discharge phase; DV is the change in the gate potential of the driving transistor T0 during the discharge phase, and DV is greater than 0.

[0111] exist Figure 3 In at least one embodiment of the photocurrent amplification circuit shown, the photoelectric sensor is a photodiode D1, and the photocurrent signal is a photoleakage current signal.

[0112] like Figure 4 As shown, this disclosure is as follows Figure 3 In at least one embodiment of the photocurrent amplifier circuit shown, the working cycle includes a reset phase P1, a compensation phase P2, a discharge phase P3, and a sampling phase P4 arranged sequentially.

[0113] During the reset phase P1, R0 provides a low voltage signal, S0 provides a high voltage signal, S1 provides a high voltage signal, T2 is turned on, and the first voltage signal is written to the gate of T0 and the first terminal of C1. Since V1 is less than V2-Vth-DV, at the beginning of the compensation phase P2, the gate-source voltage Vgs of the driving transistor T0 is V1-V2<-Vth-DV<-Vth, ensuring that the driving transistor T0 can be turned on at the beginning of the compensation phase P2.

[0114] During the compensation phase P2, S0 provides a low voltage signal, R0 provides a high voltage signal, S1 provides a high voltage signal, and T1 is turned on, so that T0 is connected in the form of a diode.

[0115] At the start of the compensation phase P2, the gate-source voltage Vgs of the driving transistor T0 is less than -Vth, so the driving transistor T0 is turned on. The second voltage terminal VT2 charges the storage capacitor C1 through the driving transistor T0. The gate voltage of the driving transistor T0 starts to rise from V1. When the gate voltage of the driving transistor T0 rises to V2-Vth, the driving transistor T0 is turned off. At this time, the gate voltage of the driving transistor T0 is V2-Vth. In the discharge phase P3, S0 provides a high voltage signal, R0 provides a high voltage signal, and S1 provides a high voltage signal. The photodiode D1 is in a reverse bias state. The photodiode D1 generates a photocurrent signal. The photocurrent signal flows from the cathode of the photodiode D1 to the anode of the photodiode D1, discharging the storage capacitor C1 and changing the gate voltage of the driving transistor T0.

[0116] At the end of the discharge phase P3, the reverse bias voltage VR of the photodiode D1 is equal to V2-Vth-DV-V1, and VR is greater than 0, so as to ensure that the photodiode D1 can always sense the light signal during the discharge phase P3 to generate the corresponding photocurrent signal.

[0117] During the discharge phase, P3, T1, and T2 are off. Photodiode D1 senses a light signal and converts it into a photocurrent signal IDR to discharge to C1. The discharge time is set to T, then the discharge charge ΔQ = IDR × T; the change in charge on C1 is Qc, Qc = C1z(V2 - Vth - V2) - IDR × T = -C1z × Vth - IDR × T; where C1z is the capacitance of C1; after discharge, the voltage across storage capacitor C1 is Vc = (-C1z × Vth - IDR) × T / C1z = -Vth - IDR × T / C1z; where Vc is the difference between the potential at the first terminal of C1 and the potential at the first terminal of C2.

[0118] During the sampling phase P4, after discharge, the gate-source voltage of T0 is Vgs = Vc = -Vth - IDR × T / C1z, and the driving current of transistor T0 is... The driving current Id is the amplified photocurrent signal; where μ is the electron migration rate, and C OX The capacitance per unit area of ​​the gate oxide layer, The aspect ratio of T0;

[0119] During the sampling phase, P4 and S1 provide low voltage signals, R0 and S0 both provide high voltage signals, and T3 is turned on to output the amplified photocurrent signal through the sampling output terminal Do.

[0120] As can be seen from the above, during the sampling phase P4, the amplified photocurrent signal is independent of Vth. Therefore, the photocurrent amplification circuit described in this embodiment has a threshold voltage compensation function.

[0121] The amplification control method described in this embodiment is applied to the above-mentioned photocurrent amplification circuit, and its working cycle includes a reset stage, a compensation stage, a discharge stage, and a sampling stage set sequentially; the amplification control method includes:

[0122] During the reset phase, under the control of the reset control signal, the reset circuit writes the first voltage signal provided by the first voltage terminal into the control terminal of the drive circuit, so that at the beginning of the compensation phase, the drive circuit can control the connection between the first terminal and the second terminal of the drive circuit under the control of the potential of its control terminal.

[0123] During the compensation phase, under the control of the compensation control signal, the compensation circuit controls the connection between the control terminal of the drive circuit and the first terminal of the drive circuit.

[0124] At the start of the compensation phase, the driving circuit, under the control of the potential at its control terminal, controls the connection between the first terminal and the second terminal of the driving circuit to charge the energy storage circuit through the second voltage signal provided by the second voltage terminal, until the driving circuit disconnects the connection between its first terminal and the second terminal. The potential at the control terminal of the driving circuit is V2-Vth, where V2 is the voltage value of the second voltage signal and Vth is the absolute value of the threshold voltage of the driving transistor included in the driving circuit.

[0125] During the discharge phase, the photoelectric sensor senses the light signal and converts the light signal into a photocurrent signal. The photocurrent signal is used to discharge the energy storage circuit, thereby changing the potential of the control terminal of the drive circuit.

[0126] During the sampling phase, the driving circuit generates an amplified photocurrent signal flowing from the second terminal of the driving circuit to the first terminal of the driving circuit under the control of the potential of its control terminal, and outputs the amplified photocurrent signal through the first terminal of the driving circuit.

[0127] The photocurrent amplification method described in this embodiment can amplify the photocurrent signal converted by the photoelectric sensor, and can amplify the pA-level photocurrent signal to the nA or uA level for external circuit sampling and detection.

[0128] Optionally, the photoelectric sensor is a photodiode; the anode of the photodiode is electrically connected to the first voltage terminal, and the cathode of the photodiode is electrically connected to the control terminal of the driving circuit; the driving circuit includes a driving transistor.

[0129] VR = V2 - Vth - DV - V1; VR is greater than 0 to ensure that the photodiode is still in reverse bias at the end of the discharge phase.

[0130] Wherein, V1 is the voltage value of the first voltage signal, V2 is the voltage value of the second voltage signal, VR is the reverse bias voltage of the photodiode at the end of the discharge phase, Vth is the threshold voltage of the driving transistor, and DV is the change in potential at the control terminal of the driving circuit during the discharge phase.

[0131] In at least one embodiment of this disclosure, the photocurrent amplification circuit further includes a sampling control circuit; the amplification control method further includes:

[0132] During the sampling phase, the sampling control circuit, under the control of the sampling control signal, controls the connection between the first terminal of the driving circuit and the sampling output terminal, so as to output the amplified photocurrent signal through the sampling output terminal.

[0133] like Figure 5 As shown, the optical detection module described in this embodiment includes the photocurrent amplification circuit 40, conversion circuit 41, and detection circuit 42 described above.

[0134] The conversion circuit 41 is electrically connected to the photocurrent amplification circuit 40 and is used to convert the amplified photocurrent signal output by the photocurrent amplification circuit 40 into an analog output voltage, and output the analog output voltage through the analog output voltage output terminal O1.

[0135] The detection circuit 42 is electrically connected to the analog output voltage output terminal O1, and is used to obtain the characteristics of the light signal sensed by the photoelectric sensor included in the photocurrent amplification circuit 40 based on the analog output voltage.

[0136] In a specific implementation, the optical detection module may include a photocurrent amplification circuit 40, a conversion circuit 41, and a detection circuit 42. The conversion circuit 41 converts the amplified photocurrent signal into an analog output voltage, and the detection circuit 42 can obtain the characteristics of the corresponding optical signal based on the analog output voltage.

[0137] In at least one embodiment of this disclosure, the characteristics of the optical signal may include light intensity and brightness;

[0138] When the photoelectric sensor includes a red photodiode, a green photodiode, and a blue photodiode (the red photodiode senses a red light signal, the green photodiode senses a green light signal, and the blue photodiode senses a blue light signal), the light characteristics such as the color coordinates and color temperature of the light signal can be calculated based on the characteristics of the red light signal sensed by the red photodiode, the characteristics of the green light signal sensed by the green photodiode, and the characteristics of the blue light signal sensed by the blue photodiode, but this is not a limitation.

[0139] like Figure 6 As shown, in Figure 5 Based on the embodiments of the optical detection module shown, the optical detection module described in at least one embodiment of this disclosure may further include a filter circuit 51;

[0140] The filter circuit 51 is connected between the analog output voltage output terminal O1 and the detection circuit 42, and is used to filter out high-frequency noise in the analog output voltage and provide the analog output voltage after filtering out high-frequency noise to the detection circuit 42.

[0141] The detection circuit 42 is used to obtain the characteristics of the optical signal based on the analog output voltage after filtering out high-frequency noise.

[0142] In at least one embodiment of this disclosure, the detection circuit may include an analog-to-digital converter and an output processing unit;

[0143] The analog-to-digital converter is used to convert the analog output voltage into a digital output voltage;

[0144] The output processing unit is electrically connected to the analog-to-digital converter and is used to receive the digital output voltage and obtain the characteristics of the optical signal based on the digital output voltage.

[0145] like Figure 7 As shown, in Figure 6 Based on at least one embodiment of the optical detection module shown, the detection circuit may include an analog-to-digital converter 61 and an output processing unit 62;

[0146] The analog-to-digital converter 61 is electrically connected to the filter circuit 51 and is used to convert the analog output voltage after filtering out high-frequency noise into a digital output voltage.

[0147] The output processing unit 62 is electrically connected to the analog-to-digital converter 61 and is used to receive the digital output voltage and obtain the characteristics of the optical signal based on the digital output voltage.

[0148] In a specific implementation, the output processing unit can be an algorithm unit that processes the output digital signal, determines the validity of the digital output voltage, converts the digital output voltage into digital signals corresponding to light intensity and brightness, and calculates optical characteristic parameters such as color coordinates or color temperature based on the output digital signals corresponding to different colors to meet the needs of the application unit.

[0149] like Figure 8 As shown, in Figure 7 Based on at least one embodiment of the optical detection module shown, the conversion circuit 41 includes an operational amplifier A1, a sampling resistor R1, and a feedback capacitor C; the photocurrent amplification circuit 40 is used to output the amplified photocurrent signal through the sampling output terminal Do.

[0150] The non-inverting input terminal of the operational amplifier A1 is electrically connected to the reference voltage terminal, the inverting input terminal of the operational amplifier A1 is electrically connected to the sampling output terminal Do, and the output terminal of the operational amplifier A1 is the analog output voltage output terminal O1; the reference voltage terminal is used to provide the reference voltage Vref.

[0151] The first end of the sampling resistor R1 is electrically connected to the inverting input terminal of the operational amplifier A1, and the second end of the sampling resistor R1 is electrically connected to the output terminal of the operational amplifier A1.

[0152] The first end of the feedback capacitor C is electrically connected to the inverting input terminal of the operational amplifier A1, and the second end of the feedback capacitor C is electrically connected to the output terminal of the operational amplifier A1.

[0153] This disclosure is as follows Figure 8 In at least one embodiment of the optical detection module shown, the analog output voltage output by O1 during operation Where R1z is the resistance value of R1; the voltage at the inverting input terminal of A1 is Vref.

[0154] like Figure 9 As shown, in Figure 8 Based on at least one embodiment of the optical detection module shown, the photocurrent amplification circuit 40 includes a photoelectric sensor, a compensation circuit, a reset circuit, an energy storage circuit, and a sampling control circuit; the photoelectric sensor is a photodiode O1;

[0155] The compensation circuit includes a first transistor T1, the reset circuit includes a second transistor T2, and the driving circuit 14 includes a driving transistor T0.

[0156] The gate of the first transistor T1 is electrically connected to the compensation control terminal S0, the drain of the first transistor T1 is electrically connected to the gate of the driving transistor T0, and the source of the first transistor T1 is electrically connected to the drain of the driving transistor T0.

[0157] The gate of the second transistor T2 is electrically connected to the reset control terminal R0, the drain of the second transistor T2 is electrically connected to the first voltage terminal VT1, and the source of the second transistor T2 is electrically connected to the gate of the driving transistor T0; the first voltage terminal VT1 is used to provide a first voltage signal.

[0158] The energy storage circuit includes a storage capacitor C1;

[0159] The first terminal of the storage capacitor C1 is electrically connected to the gate of the driving transistor T0, and the second terminal of the storage capacitor C1 is electrically connected to the source of the driving transistor T0.

[0160] The source of the driving transistor T0 is electrically connected to the second voltage terminal VT2, which is used to provide a second voltage signal.

[0161] The anode of the photodiode D1 is electrically connected to the first voltage terminal VT1, and the cathode of the photodiode D1 is electrically connected to the gate of the driving transistor T0.

[0162] The sampling control circuit includes a third transistor T3;

[0163] The gate of the third transistor T3 is electrically connected to the sampling control terminal S1, the source of the third transistor T3 is electrically connected to the source of the driving transistor T0, and the drain of the third transistor T3 is electrically connected to the sampling output terminal Do.

[0164] The filter circuit 51 includes a filter resistor R01, a first filter capacitor C01, and a second filter capacitor C02.

[0165] The first end of the filter resistor R01 is electrically connected to the analog output voltage output terminal O1, and the second end of the filter resistor R01 is electrically connected to the analog-to-digital converter 61.

[0166] The first terminal of the first filter capacitor C01 is electrically connected to the analog output voltage output terminal O1, and the second terminal of the first filter capacitor C01 is grounded.

[0167] The first terminal of the second filter capacitor C02 is electrically connected to the second terminal of the filter resistor R01, and the second terminal of the second filter capacitor C02 is grounded.

[0168] exist Figure 9 In at least one embodiment of the photoelectric detection module shown, the voltage value V1 of the first voltage signal provided by the first voltage terminal VT1 can be -1V, the voltage value V2 of the second voltage signal provided by the second voltage terminal VT2 can be 5V, and the absolute value Vth of the threshold voltage of the driving transistor T0 can be 2V, but is not limited thereto.

[0169] exist Figure 9 In at least one embodiment of the light detection module shown, T1, T2, T3 and T0 are thin-film transistors fabricated using LTPS (Low Temperature Poly-silicon) PMOS (P-type metal-oxide-semiconductor) technology, but this is a limitation.

[0170] This disclosure is as follows Figure 9 In at least one embodiment of the optical detection module shown, during the sampling phase, T3 is turned on to output the amplified photocurrent signal to the inverting input of the operational amplifier A1 through the sampling output terminal Do. The operational amplifier A1 converts the amplified photocurrent signal into an analog output voltage Vout. R01, C01, and C02 filter the analog output voltage to obtain a filtered analog output voltage. The analog-to-digital converter 61 performs analog-to-digital conversion on the filtered analog output voltage to obtain a digital output voltage. The output processing unit 62 is electrically connected to the analog-to-digital converter 61 and is used to receive the digital output voltage and obtain the characteristics of the optical signal based on the digital output voltage.

[0171] like Figure 10 As shown, this disclosure is as follows Figure 9 In at least one embodiment of the optical detection module shown, the working cycle includes a reset phase P1, a compensation phase P2, a discharge phase P3, and a sampling phase P4 arranged sequentially.

[0172] During the reset phase P1, R0 provides a low voltage signal, S0 provides a high voltage signal, S1 provides a high voltage signal, T2 is turned on, and the first voltage signal provided by the first voltage terminal VT1 is written to the first terminal of C1 so that T0 can be turned on when the compensation phase P2 begins.

[0173] During the compensation phase P2, S0 provides a low voltage signal, R0 provides a high voltage signal, S1 provides a high voltage signal, and T1 is turned on. When V1 is less than V2-Vth (Vth is the absolute value of the threshold voltage of T0), VT2 charges C1 through T0 and T1. The gate voltage of T0 starts to rise from V1. When the charging time is long enough, when the gate voltage of T0 rises to V2-Vth, T0 is turned off. Therefore, at the end of the compensation phase P2, the gate voltage of T0 is V2-Vth.

[0174] During the discharge phase P3, S0 provides a high voltage signal, R0 provides a high voltage signal, and S1 provides a high voltage signal. At the beginning of the discharge phase P3, the anode voltage of D1 is V1, and the cathode voltage of D1 is V2-Vth. V1 needs to be less than V2-Vth.

[0175] During the discharge phase, P3, T1, and T2 are off. Photodiode D1 senses a light signal and converts it into a photocurrent signal IDR to discharge to C1. The discharge time is set to T, then the discharge charge ΔQ = IDR × T; the charge change on C1 is Qc, Qc = C1z(V2 - Vth - V2) - IDR × T = -C1z × Vth - IDR × T; where C1z is the capacitance of C1; after discharge, the voltage across storage capacitor C1 is Vc = (-C1z × Vth - IDR) × T / C1z = -Vth - IDR × T / C1z; where Vc is the difference between the potential at the first terminal of C1 and the potential at the first terminal of C2.

[0176] During the sampling phase P4, after discharge, the gate-source voltage of T0 is Vgs = Vc = -Vth - IDR × T / C1z, and the driving current of transistor T0 is... The driving current Id is the amplified photocurrent signal; where μ is the electron migration rate, and C OX The capacitance per unit area of ​​the gate oxide layer, The aspect ratio of T0;

[0177] During the sampling phase P4, in order to ensure that the driving transistor operates in the saturation region, a certain bias voltage Vbias needs to be applied to T0. Vbias = V2 - Vref. Vbias is greater than 0, so that the source voltage of T0 is greater than the drain voltage of T0, resulting in a large amplification factor.

[0178] During the sampling phase P4, S1 provides a low voltage signal, R0 and S0 both provide high voltage signals, and T3 is turned on to output the amplified photocurrent signal to the inverting input of the operational amplifier A1 through the sampling output terminal Do. The operational amplifier A1 converts the amplified photocurrent signal into an analog output voltage Vout. R01, C01, and C02 filter the analog output voltage to obtain a filtered analog output voltage. The analog-to-digital converter 61 performs analog-to-digital conversion on the filtered analog output voltage to obtain a digital output voltage. The output processing unit 62 is electrically connected to the analog-to-digital converter 61 and is used to receive the digital output voltage and obtain the characteristics of the optical signal based on the digital output voltage.

[0179] The display device described in this disclosure includes the light detection module described above.

[0180] In at least one embodiment of this disclosure, the photocurrent amplification circuit included in the light detection module can be disposed on the display substrate, and the conversion circuit and the detection circuit included in the light detection module can both be disposed on the circuit board or the display driver integrated circuit.

[0181] The display device provided in this disclosure can be any product or component with display function, such as a mobile phone, tablet computer, television, monitor, laptop computer, digital photo frame, or navigator.

[0182] The above description represents the preferred embodiments of this disclosure. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles described herein, and these improvements and modifications should also be considered within the scope of protection of this disclosure.

Claims

1. A photocurrent amplifier circuit, characterized in that, It includes a photoelectric sensor, a compensation circuit, a reset circuit, an energy storage circuit, and a drive circuit, among which, The photoelectric sensor is used to sense light signals, convert the light signals into photocurrent signals, and provide the photocurrent signals to the control terminal of the driving circuit; The compensation circuit is electrically connected to the compensation control terminal, the control terminal of the drive circuit, and the first terminal of the drive circuit, respectively, and is used to control the connection between the control terminal of the drive circuit and the first terminal of the drive circuit under the control of the compensation control signal provided by the compensation control terminal; The reset circuit is electrically connected to the reset control terminal, the first voltage terminal and the control terminal of the drive circuit, respectively, and is used to control the connection between the first voltage terminal and the control terminal of the drive circuit under the control of the reset control signal provided by the reset control terminal. The first terminal of the energy storage circuit is electrically connected to the control terminal of the drive circuit, and the second terminal of the energy storage circuit is electrically connected to the second terminal of the drive circuit. The energy storage circuit is used to store electrical energy. The second terminal of the driving circuit is electrically connected to the second voltage terminal. The driving circuit is used to generate an amplified photocurrent signal flowing through the second terminal and the first terminal of the driving circuit under the control of the potential of its control terminal.

2. The photocurrent amplifier circuit as described in claim 1, characterized in that, It also includes a sampling control circuit; The sampling control circuit is electrically connected to the sampling control terminal, the first terminal of the driving circuit, and the sampling output terminal, respectively. Under the control of the sampling control signal provided by the sampling control terminal, it controls the connection between the first terminal of the driving circuit and the sampling output terminal so as to output the amplified photocurrent signal through the sampling output terminal.

3. The photocurrent amplifier circuit as described in claim 1, characterized in that, The compensation circuit includes a first transistor, and the reset circuit includes a second transistor; The control electrode of the first transistor is electrically connected to the compensation control terminal, the first electrode of the first transistor is electrically connected to the control terminal of the driving circuit, and the second electrode of the first transistor is electrically connected to the first terminal of the driving circuit. The control electrode of the second transistor is electrically connected to the reset control terminal, the first electrode of the second transistor is electrically connected to the first voltage terminal, and the second electrode of the second transistor is electrically connected to the control terminal of the drive circuit.

4. The photocurrent amplifier circuit as described in claim 1, characterized in that, The energy storage circuit includes a storage capacitor, and the driving circuit includes a driving transistor; The control terminal of the driving transistor is the control terminal of the driving circuit, the first terminal of the driving transistor is the first terminal of the driving circuit, and the second terminal of the driving transistor is the second terminal of the driving circuit. The first terminal of the storage capacitor is electrically connected to the control electrode of the driving transistor, and the second terminal of the storage capacitor is electrically connected to the second electrode of the driving transistor.

5. The photocurrent amplifier circuit as described in claim 1, characterized in that, The photoelectric sensor is a photodiode; The anode of the photodiode is electrically connected to the first voltage terminal, and the cathode of the photodiode is electrically connected to the control terminal of the driving circuit.

6. The photocurrent amplifier circuit as described in claim 2, characterized in that, The sampling control circuit includes a third transistor; The control electrode of the third transistor is electrically connected to the sampling control terminal, the first electrode of the third transistor is electrically connected to the first terminal of the driving circuit, and the second electrode of the third transistor is electrically connected to the sampling output terminal.

7. An amplification control method, applied to the photocurrent amplification circuit as described in any one of claims 1 to 6, characterized in that, The working cycle includes a reset phase, a compensation phase, a discharge phase, and a sampling phase, which are set sequentially. The amplification control method includes: During the reset phase, under the control of the reset control signal, the reset circuit writes the first voltage signal provided by the first voltage terminal into the control terminal of the drive circuit, so that at the beginning of the compensation phase, the drive circuit can control the connection between the first terminal and the second terminal of the drive circuit under the control of the potential of its control terminal. During the compensation phase, under the control of the compensation control signal, the compensation circuit controls the connection between the control terminal of the drive circuit and the first terminal of the drive circuit. At the start of the compensation phase, the driving circuit, under the control of the potential at its control terminal, controls the connection between the first terminal and the second terminal of the driving circuit to charge the energy storage circuit through the second voltage signal provided by the second voltage terminal, until the driving circuit disconnects the connection between its first terminal and the second terminal. The potential at the control terminal of the driving circuit is V2-Vth, where V2 is the voltage value of the second voltage signal and Vth is the absolute value of the threshold voltage of the driving transistor included in the driving circuit. During the discharge phase, the photoelectric sensor senses the light signal and converts the light signal into a photocurrent signal. The photocurrent signal is used to discharge the energy storage circuit, thereby changing the potential of the control terminal of the drive circuit. During the sampling phase, the driving circuit generates an amplified photocurrent signal flowing from the second terminal of the driving circuit to the first terminal of the driving circuit under the control of the potential of its control terminal, and outputs the amplified photocurrent signal through the first terminal of the driving circuit.

8. The amplification control method as described in claim 7, characterized in that, The photoelectric sensor is a photodiode; the anode of the photodiode is electrically connected to the first voltage terminal, and the cathode of the photodiode is electrically connected to the control terminal of the driving circuit; the driving circuit includes a driving transistor. VR = V2 - Vth - DV - V1; VR > 0; Wherein, V1 is the voltage value of the first voltage signal, V2 is the voltage value of the second voltage signal, VR is the reverse bias voltage of the photodiode at the end of the discharge phase, Vth is the threshold voltage of the driving transistor, and DV is the change in potential at the control terminal of the driving circuit during the discharge phase.

9. The amplification control method as described in claim 7 or 8, characterized in that, The photocurrent amplification circuit further includes a sampling control circuit; the amplification control method further includes: During the sampling phase, the sampling control circuit, under the control of the sampling control signal, controls the connection between the first terminal of the driving circuit and the sampling output terminal, so as to output the amplified photocurrent signal through the sampling output terminal.

10. A light detection module, characterized in that, Includes the photocurrent amplification circuit, conversion circuit, and detection circuit as described in any one of claims 1 to 6; The conversion circuit is electrically connected to the photocurrent amplifier circuit and is used to convert the amplified photocurrent signal output by the photocurrent amplifier circuit into an analog output voltage, and output the analog output voltage through the analog output voltage output terminal. The detection circuit is used to obtain the characteristics of the optical signal sensed by the photoelectric sensor included in the photocurrent amplifier circuit based on the analog output voltage.

11. The optical detection module as described in claim 10, characterized in that, It also includes a filter circuit; The filtering circuit is connected between the analog output voltage output terminal and the detection circuit, and is used to filter out high-frequency noise in the analog output voltage and provide the analog output voltage after filtering out high-frequency noise to the detection circuit. The detection circuit is used to obtain the characteristics of the optical signal based on the analog output voltage after filtering out high-frequency noise.

12. The optical detection module as described in claim 10, characterized in that, The detection circuit includes an analog-to-digital converter and an output processing unit; The analog-to-digital converter is used to convert the analog output voltage into a digital output voltage; the output processing unit is electrically connected to the analog-to-digital converter and is used to receive the digital output voltage and obtain the characteristics of the optical signal based on the digital output voltage.

13. The optical detection module as described in claim 10, characterized in that, The conversion circuit includes an operational amplifier, a sampling resistor, and a feedback capacitor; the photocurrent amplification circuit is used to output the amplified photocurrent signal through the sampling output terminal. The non-inverting input terminal of the operational amplifier is electrically connected to the reference voltage terminal, the inverting input terminal of the operational amplifier is electrically connected to the sampling output terminal, and the output terminal of the operational amplifier is the analog output voltage output terminal. The first end of the sampling resistor is electrically connected to the inverting input terminal of the operational amplifier, and the second end of the sampling resistor is electrically connected to the output terminal of the operational amplifier. The first end of the feedback capacitor is electrically connected to the inverting input terminal of the operational amplifier, and the second end of the feedback capacitor is electrically connected to the output terminal of the operational amplifier.

14. A display device, characterized in that, Includes the optical detection module as described in any one of claims 10 to 13.

15. The display device as claimed in claim 14, characterized in that, The photocurrent amplification circuit included in the light detection module is disposed on the display substrate, and the conversion circuit and the detection circuit included in the light detection module are both disposed on the circuit board or the display driver integrated circuit.

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