EEG signal detection device and brain-computer interface device

Abstract

The present disclosure relates to a device for detecting electroencephalogram signals, belonging to the technical field of brain-computer interface equipment, the device comprises a control circuit; at least one channel electrode circuit, a first end of the channel electrode circuit is electrically connected to the control circuit, a second end of the channel electrode circuit is an end for connecting to a measured object, and a control end of at least one channel electrode circuit is connected to a control end of the control circuit; a common electrode circuit, a first end of the common electrode circuit is electrically connected to the control circuit, and a second end of the common electrode circuit is an end for connecting to a measured object; wherein the common electrode circuit and the channel electrode circuit reuse some components, and some components include filter components and protection components.

Description

Technical Field

[0001] The embodiments of the present disclosure relate to the technical field of brain-computer interface devices, and more specifically, to an electroencephalogram signal detection device and a brain-computer interface device. Background Art

[0002] With the rapid development of brain-computer interface devices, the impedance of the brain-computer interface devices themselves will affect the signal quality of EEG signals. Therefore, impedance detection of brain-computer interface devices can effectively determine the signal quality of EEG signals. In the prior art, multiple channels of brain-computer interface devices can respectively collect EEG signals at different positions of the head of the subject. During the impedance detection process, an external excitation source needs to be additionally applied to detect the impedance, but the external excitation source itself also has impedance, which makes the detected impedance less accurate. Summary of the invention

[0003] One purpose of the embodiments of the present disclosure is to provide a new technical solution for an electroencephalogram signal detection device and a brain-computer interface device.

[0004] According to a first aspect of the present disclosure, there is provided a device for detecting an electroencephalogram signal, the device comprising:

[0005] Control circuit;

[0006] At least one channel electrode circuit, a first end of the channel electrode circuit is electrically connected to the control circuit, a second end of the channel electrode circuit is an end for connecting to a measured object, and a control end of at least one channel electrode circuit is connected to a control end of the control circuit;

[0007] A common electrode circuit, wherein a first end of the common electrode circuit is electrically connected to the control circuit, and a second end of the common electrode circuit is an end for connecting to an object to be measured;

[0008] Wherein, the common electrode circuit and the channel electrode circuit reuse some devices, and the some devices include filtering devices and protection devices; when the control circuit outputs an excitation source signal for detecting impedance to the common electrode circuit, the control end of the control circuit sequentially outputs a driving signal to the control end of at least one of the channel electrode circuits, so that at least one of the channel electrode circuits responds to the driving signal output by the control end of the control circuit and the filtered excitation source signal output by the reused some devices, and outputs a feedback signal to the control circuit through the first end of the channel electrode circuit; wherein, the feedback signal is data for the control circuit to determine the impedance in the corresponding channel electrode circuit.

[0009] Optionally, the common electrode circuit and the channel electrode circuit reuse some components, including: the common electrode circuit and the channel electrode circuit reuse a filtering protection circuit;

[0010] The filtering protection circuit includes a first resistor, a first capacitor and a transient suppression diode, the first capacitor is connected across the first resistor and the ground terminal of the detection device, and the transient suppression diode is connected across the first resistor and the ground terminal of the detection device.

[0011] Optionally, the channel electrode circuit further includes a first electrode sheet, a first operational amplifier circuit and a switch circuit;

[0012] Among them, the first electrode sheet is a component attached to the object to be measured, the multiplexing part device is connected between the first electrode sheet and the first end of the first operational amplifier circuit, the second end of the first operational amplifier circuit serves as the first end of the channel electrode circuit, the switching circuit is connected to the connection point between the multiplexing part device and the first operational amplifier circuit, and the control end of the switching circuit is the control end of the channel electrode circuit.

[0013] Optionally, the device further comprises a reference electrode circuit, a first end of the reference electrode circuit is electrically connected to the control circuit, and a second end of the reference electrode circuit is an end for connecting to the object to be measured;

[0014] The first operational amplifier circuit includes a first operational amplifier, a second resistor and a third resistor; the non-inverting input terminal of the first operational amplifier is connected to the multiplexing part device, the inverting input terminal of the first operational amplifier is connected in series with the second resistor and then connected to the reference electrode circuit, the third resistor is connected between the output terminal and the inverting input terminal of the first operational amplifier, and the output terminal of the first operational amplifier is connected to the control circuit.

[0015] Optionally, the switch circuit includes a first switch and a fourth resistor;

[0016] One end of the first switch is connected to the connection point between the multiplexing part device and the first operational amplifier circuit, and the fourth circuit is connected between the other end of the first switch and the ground terminal of the detection device; the control end of the first switch is the control end of the channel electrode circuit.

[0017] Optionally, the channel electrode circuit further includes a display circuit, and the display circuit is connected between a control end of the channel electrode circuit and a control end of the control circuit.

[0018] Optionally, the common electrode circuit further includes a second electrode sheet, a second operational amplifier circuit and a filter circuit;

[0019] Among them, the second electrode sheet is a component attached to the object to be measured, the multiplexing part device is connected between the second electrode sheet and the second operational amplifier circuit, the first end of the filter circuit is electrically connected to the second operational amplifier circuit, and the second end of the filter circuit serves as the first end of the common electrode circuit.

[0020] Optionally, the second operational amplifier circuit includes a second operational amplifier, a fifth resistor and a sixth resistor, the non-inverting input terminal of the second operational amplifier is connected to the multiplexing part device, the fifth resistor is connected between the output terminal and the inverting input terminal of the second operational amplifier, and the sixth resistor is connected between the fifth resistor and the ground terminal of the detection device;

[0021] The filtering circuit includes a seventh resistor and a second capacitor, wherein the seventh resistor is connected between the output terminal of the second operational amplifier and the control circuit, and the second capacitor is connected between the seventh resistor and the ground terminal of the detection device.

[0022] According to a second aspect of the present disclosure, a brain-computer interface device is also provided, comprising the detection device as described in the first aspect.

[0023] Optionally, the brain-computer interface device further includes a splitter;

[0024] Wherein, the channel electrode circuit and the common electrode circuit in the detection device are arranged in the divider.

[0025] One beneficial effect of the embodiments of the present disclosure is that the control circuit can output an excitation source signal to the channel electrode circuit, and the control circuit outputs a driving signal to the channel electrode circuit, so that each channel electrode circuit responds to the driving signal and the filtered excitation source signal in turn and outputs a feedback signal to the control circuit. The control circuit can determine the impedance of the channel electrode circuit based on the feedback signal, and further determine the impedance of each channel electrode circuit, thereby effectively improving the accuracy of the detected impedance.

[0026] Other features and advantages of the embodiments of the present disclosure will become apparent from the following detailed description of exemplary embodiments of the present disclosure with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the present disclosure and, together with the description, serve to explain the principles of the embodiments of the present disclosure.

[0028] Figure 1 is a schematic diagram of the structure of a device for detecting an electroencephalogram signal according to an embodiment;

[0029] Figure 2 is a schematic diagram of the composition structure of a brain-computer interface device according to an embodiment;

[0030] Figure 3 is a schematic diagram of the composition structure of a channel electrode circuit according to an embodiment;

[0031] Figure 4 is a circuit diagram of a channel electrode circuit according to one embodiment;

[0032] Figure 5 is a schematic diagram of the composition structure of a channel electrode circuit according to another embodiment;

[0033] Figure 6 is a circuit diagram of a switching circuit according to an embodiment;

[0034] Figure 7 is a circuit diagram of a first operational amplifier circuit according to one embodiment;

[0035] Figure 8 is a schematic diagram of the structure of a common electrode circuit according to an embodiment;

[0036] Fig. 9 is a circuit diagram of a common electrode circuit according to one embodiment;

[0037] Fig.10 It is a schematic diagram of the composition structure of a brain-computer interface device according to another embodiment.

[0038] Description of the drawings:

[0039] 10. Control circuit; 20. Channel electrode circuit; 30. Common electrode circuit; 40. Reference electrode circuit; 50. Auxiliary power supply;

[0040] 1. Object to be measured; 2. Conductive medium; 31. First electrode sheet; 32. Second electrode sheet; 33. Third electrode sheet; 7. Electrode cable; 8. EEG amplifier; 9. Control chip; 11. Splitter. DETAILED DESCRIPTION

[0041] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that the relative arrangement of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present invention unless otherwise specifically stated.

[0042] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses.

[0043] Techniques and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the techniques and equipment should be considered part of the specification.

[0044] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0045] It should be noted that like reference numerals and letters refer to similar items in the following figures, and therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0046] Figure 1 A schematic structural diagram of a device for detecting an electroencephalogram signal according to an embodiment is shown.

[0047] According to the detection device in this embodiment, the detection device includes a control circuit 10, at least one channel electrode circuit 20 and a common electrode circuit 30. The control circuit 10 can be a circuit mounted on a terminal device, and the terminal device is, for example, a computer, a tablet or a mobile phone. There can be multiple channel electrode circuits 20, and the channel electrode circuits 20 can collect EEG signals at different positions of the head of the object 1 under test. In some examples, the number of channel electrode circuits 20 is, for example, 16 or 32, and these channel electrode circuits 20 can collect EEG signals at various positions of the head of the object 1 under test.

[0048] At least one channel electrode circuit 20, the first end of the channel electrode circuit 20 is electrically connected to the control circuit 10, the second end of the channel electrode circuit 20 is an end for connecting to the object under test 1, and the control end of at least one channel electrode circuit 20 is connected to the control end of the control circuit 10.

[0049] The common electrode circuit 30 has a first end electrically connected to the control circuit 10, and a second end of the common electrode circuit 30 is used to connect to the object under test 1. The common electrode circuit 30 and at least one channel electrode circuit 20 reuse some components, including filter components and protection components.

[0050] The user can confirm the program of starting impedance detection on the above terminal device. The terminal device can output the excitation source signal for detecting impedance to the common electrode circuit 30 through the control circuit 10. Under the filtering effect of the multiplexing device, the common electrode circuit 30 receives the filtered excitation source signal. The control circuit 10 can sequentially output the driving signal to the control end of at least one channel electrode circuit 20, so that at least one channel electrode circuit 20 is sequentially turned on, and the multiplexing part device can output the excitation source signal to one of the turned-on channel electrode circuits 20, so that the turned-on channel electrode circuit 20 operates in response to the filtered excitation source signal, generates and outputs the feedback signal. The control circuit 10 receives the feedback signal and calculates the impedance value in the turned-on channel electrode circuit 20 through the change curve corresponding to the feedback signal, so that the user can determine the signal quality of the turned-on channel electrode circuit 20. In other words, the common electrode circuit 30 outputs the filtered excitation source signal to the channel electrode circuit 20, effectively reducing the occurrence of additional excitation sources and effectively improving the accuracy of the detected impedance.

[0051] In some embodiments, Figure 1 and Figure 2 As shown, the detection device further includes a reference electrode circuit 40, a first end of the reference electrode circuit 40 is electrically connected to the control circuit 10, and a second end of the reference electrode circuit 40 is an end for connecting to the object to be measured 1. The reference electrode circuit 40 is a prior art and will not be elaborated here. The reference circuit in the reference electrode circuit 40 is connected to the control circuit 10 as the first end of the reference electrode level, and the third electrode sheet 33 in the reference electrode circuit 40 is the second end of the reference electrode circuit 40, which can be attached to the position around the ear of the object to be measured 1 to output a reference signal to the control circuit 10.

[0052] In some embodiments, Figure 2 As shown, the control circuit 10 may include a plurality of electrode cables 7, an EEG amplifier 8 and a control chip 9, each electrode cable 7 is respectively connected to a different electrode circuit, that is, each channel electrode circuit 20, common electrode circuit 30 and reference electrode circuit 40 is connected to one end of a different electrode cable 7. The other end of the electrode cable 7 is connected to the first end of the EEG amplifier 8, and the second end of the EEG amplifier 8 is connected to the control chip 9, so that the signals output by each electrode cable 7 can be processed by the EEG amplifier 8 after analog-to-digital conversion and filtering to obtain processed signals output to the control chip 9, and the control chip 9 can determine the brain activity of the subject 1 through these processed signals.

[0053] In some embodiments, Figure 3As shown, the channel electrode circuit 20 may include a multiplexing part device, a first electrode sheet 31, a first operational amplifier circuit SC2 and a switch circuit SC3. The first electrode sheet 31 is a component attached to the object 1 to be measured to collect the EEG signal of the object 1 to be measured. The multiplexing part device is connected between the first electrode sheet 31 and the first end of the first operational amplifier circuit SC2, and the EEG signal collected by the first electrode sheet 31 can be filtered. The second end of the first operational amplifier circuit SC2 serves as the first end of the channel electrode circuit 20. The first operational amplifier circuit SC2 can process the filtered EEG signal to obtain an amplified EEG signal, and output the amplified EEG signal to the control circuit 10. In some examples, the channel electrode circuit 20 also includes a power management circuit SC4, which is electrically connected to the auxiliary power supply 50 in the power supply device, so that the power management circuit SC4 can supply power to the first operational amplifier circuit SC2.

[0054] The switch circuit SC3 is connected to the connection point between the multiplexing part device and the first operational amplifier circuit SC2, and the control end of the switch circuit SC3 is the control end of the channel electrode circuit 20. In the case where the control circuit 10 outputs an excitation source signal for detecting impedance to the common electrode circuit 30, the control circuit 10 sequentially outputs a driving signal to the control end of each switch circuit SC3, so that each switch circuit SC3 is turned on in turn, so that the load in the switch circuit SC3 is turned on with the line of the first operational amplifier circuit SC2, and then the excitation source signal input to the multiplexing part device can be input to the first operational amplifier circuit SC2, and the first operational amplifier circuit SC2 outputs a feedback signal to the control circuit 10 under the action of the load and the excitation source signal, so that the control circuit 10 can determine the impedance in the channel electrode circuit 20 according to the feedback signal.

[0055] In some embodiments, Figure 2 and Figure 3 As shown, the multiplexed part device is a multiplexed filter protection circuit SC1. The filter protection circuit SC1 includes a first resistor R1, a first capacitor C1 and a transient suppression diode D1. The first capacitor C1 is connected across the first resistor R1 and the ground terminal of the detection device, and the transient suppression diode D1 is connected across the first resistor R1 and the ground terminal of the detection device. Among them, the transient suppression diode D1 can absorb peak voltage or current to protect the components in the channel electrode circuit 20. The first resistor R1 and the first capacitor C1 form a filter to filter the EEG signal output by the first electrode sheet 31 to improve the stability of the output EEG signal.

[0056] In some embodiments, Figure 2 and Figure 3As shown, the first operational amplifier circuit SC2 includes a first operational amplifier U1, a second resistor R2 and a third resistor R3. The non-inverting input terminal of the first operational amplifier U1 is connected to the multiplexing part device, the inverting input terminal of the first operational amplifier U1 is connected to the reference electrode circuit 40 after being connected in series with the second resistor R2, the third resistor R3 is connected between the output terminal and the inverting input terminal of the first operational amplifier U1, and the output terminal of the first operational amplifier U1 is connected to the control circuit 10. The first operational amplifier U1 can process the EEG signal output by the multiplexing part device to enable the subsequent control circuit 10 to detect the EEG signal output by the channel electrode circuit 20.

[0057] In some embodiments, Figure 2 and Figure 3 As shown, the switch circuit SC3 includes a first switch U2 and a fourth resistor R4; one end of the first switch U2 is connected to the connection point of the multiplexing part device and the first operational amplifier circuit SC2, and the fourth resistor R4 is connected between the other end of the first switch U2 and the ground end of the detection device; the control end of the first switch U2 is the control end of the channel electrode circuit 20. The first switch U2 is controlled by the driving signal output by the control circuit 10, and the first switch U2 is closed in response to the driving signal, so that the line between the fourth resistor R4 as a load and the first operational amplifier U1 is turned on, so that under the shunting effect of the fourth resistor R4, part of the filtered excitation source signal is input into the first operational amplifier U1, and the first operational amplifier U1 processes part of the filtered excitation source signal and outputs it to the control circuit 10, so that the control circuit 10 determines the impedance in the channel electrode circuit 20 through the signal output by the first operational amplifier U1. In other words, since the resistance value of the fourth resistor R4 is fixed, the signal output by the first operational amplifier U1 after the fourth resistor R4 is connected to the first operational amplifier U1 can reflect the overall impedance value of the channel electrode circuit 20. The signal output by the first operational amplifier U1 can be compared with a preset standard impedance curve in the control circuit 10 to determine whether the signal exceeds the amplitude of the preset standard impedance curve, so as to judge whether the impedance of the channel electrode circuit 20 is too high.

[0058] In some embodiments, Figure 2 and Figure 3 As shown, the channel electrode circuit 20 further includes a display circuit SC5 , and the display circuit SC5 is connected between a control terminal of the channel electrode circuit 20 and a control terminal of the control circuit 10 .

[0059] In some embodiments, Figure 3As shown, the display circuit SC5 includes a first light emitting diode D2, a second light emitting diode D3, an eighth resistor R8, a ninth resistor R9 and an IC chip U3, wherein the first end of the IC chip U3 is connected to the control end of the control circuit 10, and the second end of the IC chip U3 is connected to the control end of the channel electrode circuit 20. The third end of the IC chip U3 is connected to one end of the eighth resistor R8, the other end of the eighth resistor R8 is connected to the anode of the first light emitting diode D2, and the cathode of the first light emitting diode D2 is connected to the ground end of the detection device. The fourth end of the IC chip U3 is connected to one end of the ninth resistor R9, the other end of the ninth resistor R9 is connected to the anode of the second light emitting diode D3, and the cathode of the second light emitting diode D3 is connected to the ground end of the detection device. In other words, the control circuit 10 can output a driving signal to the control end of the channel electrode circuit 20 through the IC chip U3, and the IC chip U3 can control one of the first light emitting diode D2 or the second light emitting diode D3 to light up in response to the driving signal. When the channel electrode circuit 20 outputs an electroencephalogram signal to the control circuit 10, the other light emitting diode lights up to remind the user whether the channel electrode circuit 20 is working normally.

[0060] In some embodiments, Figure 4 As shown, the switch circuit SC3 can be directly connected to the electrode cable 7 corresponding to the common electrode circuit 30, and directly output a driving signal to the control end of the switch circuit SC3 through the control circuit 10.

[0061] In some examples, such as Figure 5 As shown, the switch circuit SC3 further includes a third capacitor C3, which is electrically connected between the fourth resistor R4 and the ground terminal of the detection device to play a filtering role.

[0062] In some examples, such as Figure 2 and Figure 7 As shown, the common electrode circuit 30 may include a multiplexing part device, a second electrode sheet 32, a second operational amplifier circuit SC6 and a filter circuit SC7. The second electrode sheet 32 ​​is a component attached to the object 1 to collect the EEG signal of the object 1. The multiplexing part device is connected between the second electrode sheet 32 ​​and the first end of the second operational amplifier circuit SC6, the first end of the filter circuit SC7 is electrically connected to the second end of the second operational amplifier circuit SC6, and the second end of the filter circuit SC7 is electrically connected to the control circuit 10 as the first end of the common electrode circuit 30.

[0063] In some examples, such as Figure 8As shown, the second operational amplifier circuit SC6 includes a second operational amplifier U4, a fifth resistor R5 and a sixth resistor R6, the in-phase input terminal of the second operational amplifier U4 is connected to the first resistor R1, the fifth resistor R5 is connected between the output terminal and the inverting input terminal of the second operational amplifier U4, and the sixth resistor R6 is connected between the fifth resistor R5 and the ground terminal of the detection device. The filter circuit SC7 includes a seventh resistor R7 and a second capacitor C2, the seventh resistor R7 is connected between the output terminal of the second operational amplifier U4 and the electrode cable 7 corresponding to the common electrode circuit 30, and the second capacitor C2 is connected between the seventh resistor R7 and the ground terminal of the detection device. In other words, by multiplexing some devices and the filter circuit SC7 to filter the EEG signal, the stability of the EEG signal output can be improved, and the accuracy of the EEG signal obtained by the control circuit 10 from the common electrode circuit 30 can be improved.

[0064] In some examples, a conductive medium 2, such as electrode paste or electrode liquid, may be coated between each electrode sheet and the object to be measured 1 to improve the conductivity between the object to be measured 1 and the electrode sheet.

[0065] According to another embodiment of the brain-computer interface device, Figure 2 As shown, the brain-computer interface device includes a detection device of any of the above embodiments. The detection device can be fully integrated on the brain-computer interface device, and each electrode sheet of the detection device can be extended and attached to the head of the object 1 under test. In other words, the brain-computer interface device provided with the detection device can also have the function of detecting the impedance in each electrode circuit, so as to facilitate the brain-computer interface device to detect the signal quality of the collected EEG signal.

[0066] In some examples, such as Fig. 9 As shown, the brain-computer interface device includes a splitter 11, and at least one of the channel electrode circuit 20, the common electrode circuit 30, and the reference electrode circuit 40 in the detection device can be integrated on the splitter 11, and each electrode sheet extending from the splitter 11 can be attached to the head of the object to be detected 1. In other words, each electrode circuit is integrated on the splitter 11 to facilitate detection of each electrode circuit.

[0067] Although some specific embodiments of the present invention have been described in detail by way of example, it will be appreciated by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the present invention. It will be appreciated by those skilled in the art that the above embodiments may be modified without departing from the scope and spirit of the present invention. The scope of the present invention is defined by the appended claims.

Claims

1. A device for detecting an electroencephalogram signal, characterized in that: The device comprises: Control circuit; At least one channel electrode circuit, a first end of the channel electrode circuit is electrically connected to the control circuit, a second end of the channel electrode circuit is an end for connecting to a measured object, and a control end of at least one channel electrode circuit is connected to a control end of the control circuit; A common electrode circuit, wherein a first end of the common electrode circuit is electrically connected to the control circuit, and a second end of the common electrode circuit is an end for connecting to an object to be measured; Wherein, the common electrode circuit and the channel electrode circuit reuse some devices, and the some devices include filtering devices and protection devices; when the control circuit outputs an excitation source signal for detecting impedance to the common electrode circuit, the control end of the control circuit sequentially outputs a driving signal to the control end of at least one of the channel electrode circuits, so that at least one of the channel electrode circuits responds to the driving signal output by the control end of the control circuit and the filtered excitation source signal output by the reused part of the devices, and outputs a feedback signal to the control circuit through the first end of the channel electrode circuit; wherein the feedback signal is data for determining the impedance in the corresponding channel electrode circuit by the control circuit; The channel electrode circuit further includes a first electrode sheet, a first operational amplifier circuit and a switch circuit; wherein the first electrode sheet is a component attached to the object to be measured, the multiplexing part device is connected between the first electrode sheet and the first end of the first operational amplifier circuit, the second end of the first operational amplifier circuit serves as the first end of the channel electrode circuit, the switch circuit is connected to the connection point between the multiplexing part device and the first operational amplifier circuit, and the control end of the switch circuit is the control end of the channel electrode circuit; The switching circuit includes a first switch, a fourth resistor and a third capacitor; wherein one end of the first switch is connected to the connection point between the multiplexing part device and the first operational amplifier circuit, and the fourth resistor is connected between the other end of the first switch and the ground terminal of the detection device; the control end of the first switch is the control end of the channel electrode circuit; and the third capacitor is electrically connected between the fourth resistor and the ground terminal of the detection device.

2. The detection device according to claim 1, characterized in that: The common electrode circuit and the channel electrode circuit reuse some components, including: the common electrode circuit and the channel electrode circuit reuse filtering protection circuit; The filtering protection circuit includes a first resistor, a first capacitor and a transient suppression diode, the first capacitor is connected across the first resistor and the ground terminal of the detection device, and the transient suppression diode is connected across the first resistor and the ground terminal of the detection device.

3. The detection device according to claim 1, characterized in that: The device further comprises a reference electrode circuit, a first end of the reference electrode circuit is electrically connected to the control circuit, and a second end of the reference electrode circuit is an end for connecting to the object to be measured; The first operational amplifier circuit includes a first operational amplifier, a second resistor and a third resistor; the non-inverting input terminal of the first operational amplifier is connected to the multiplexing part device, the inverting input terminal of the first operational amplifier is connected in series with the second resistor and then connected to the reference electrode circuit, the third resistor is connected between the output terminal and the inverting input terminal of the first operational amplifier, and the output terminal of the first operational amplifier is connected to the control circuit.

4. The detection device according to claim 1, characterized in that: The channel electrode circuit further includes a display circuit, and the display circuit is connected between a control end of the channel electrode circuit and a control end of the control circuit.

5. The detection device according to any one of claims 1 to 4, characterized in that: The common electrode circuit also includes a second electrode sheet, a second operational amplifier circuit and a filter circuit; Among them, the second electrode sheet is a component attached to the object to be measured, the multiplexing part device is connected between the second electrode sheet and the second operational amplifier circuit, the first end of the filter circuit is electrically connected to the second operational amplifier circuit, and the second end of the filter circuit serves as the first end of the common electrode circuit.

6. The detection device according to claim 5, characterized in that: The second operational amplifier circuit includes a second operational amplifier, a fifth resistor and a sixth resistor, the non-inverting input terminal of the second operational amplifier is connected to the multiplexing part device, the fifth resistor is connected between the output terminal and the inverting input terminal of the second operational amplifier, and the sixth resistor is connected between the fifth resistor and the ground terminal of the detection device; The filtering circuit includes a seventh resistor and a second capacitor, wherein the seventh resistor is connected between the output terminal of the second operational amplifier and the control circuit, and the second capacitor is connected between the seventh resistor and the ground terminal of the detection device.

7. A brain-computer interface device, characterized in that: Comprising a detection device as described in any one of claims 1 to 6.

8. The brain-computer interface device according to claim 7, characterized in that: The brain-computer interface device also includes a splitter; Wherein, the channel electrode circuit and the common electrode circuit in the detection device are arranged in the divider.

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