Electrode patch and electroencephalogram signal processing system

Abstract

The application provides an electrode patch and an electroencephalogram processing system, which comprises a flexible substrate, an electroencephalogram electrode layer, a shielding layer, a stimulating electrode layer and a conductive structure which are stacked in sequence. The flexible substrate is attached to the skin of the head of a subject; the electroencephalogram electrode layer collects electroencephalogram signals in a first frequency range; the stimulating electrode layer applies an electric field in a second frequency range; the lower limit of the second frequency range is higher than the upper limit of the first frequency range; the shielding layer is arranged between the electroencephalogram electrode layer and the stimulating electrode layer, and the shielding layer is electrically connected to a reference electrode; the conductive structure penetrates through the shielding layer and is electrically connected to the electroencephalogram electrode layer; the conductive structure is insulated from the shielding layer and the stimulating electrode layer; in the working state, the stimulating electrode layer, the shielding layer and the skin of the head form a cascaded capacitor, so that the stimulating electrode layer applies an electric field in a capacitive coupling mode. Direct penetration of high-frequency current can be blocked; and the collected electroencephalogram signals can reflect the neural response of the direct action area of the treatment electric field in real time.

Description

Technical Field

[0001] This application relates to the field of medical device technology, and more specifically, to an electrode patch and an electroencephalogram (EEG) signal processing system. Background Technology

[0002] Tumor electric field therapy is a treatment method that interferes with the mitotic process of tumor cells by applying a low-intensity, medium-frequency alternating electric field. It is non-invasive and highly selective.

[0003] However, existing devices typically use preset modes and lack the ability to dynamically adjust based on the patient's current physiological state, which limits the accuracy and safety of treatment. Utility Model Content

[0004] This application addresses the shortcomings of existing methods by proposing an electrode patch and an EEG signal processing system to solve the technical problems existing in related technologies.

[0005] In a first aspect, embodiments of this application provide an electrode patch, comprising: a flexible substrate, an EEG electrode layer, a shielding layer and a stimulation electrode layer stacked sequentially, and a conductive structure; The flexible substrate is used to be applied to the scalp of the subject; The EEG electrode layer is used to collect EEG signals in a first frequency range; The stimulation electrode layer is used to apply an electric field in a second frequency range; the lower limit of the second frequency range is higher than the upper limit of the first frequency range; A shielding layer is disposed between the EEG electrode layer and the stimulation electrode layer, and the shielding layer is used for electrical connection with the reference electrode. The conductive structure penetrates the shielding layer and is electrically connected to the EEG electrode layer; the conductive structure is insulated from both the shielding layer and the stimulation electrode layer. In operation, the stimulation electrode layer, the shielding layer, and the scalp form a cascaded capacitor, so that the stimulation electrode layer applies an electric field in a capacitively coupled manner.

[0006] Optionally, the electrode patch also includes: A first insulating layer is disposed between the EEG electrode layer and the shielding layer; A second insulating layer is disposed between the shielding layer and the stimulating electrode layer; The through-hole sequentially penetrates the stimulation electrode layer, the second insulating layer, the shielding layer, and the first insulating layer; An insulating structure covers the inner peripheral sidewall of the through hole; The conductive structure fills the through hole.

[0007] Optionally, the through hole is spirally disposed through the stimulation electrode layer, the second insulating layer, the shielding layer and the first insulating layer.

[0008] Optionally, the orthographic projection of the shielding layer on the flexible substrate at least partially overlaps with the orthographic projection of the stimulation electrode of the stimulation electrode layer on the flexible substrate.

[0009] Optionally, the shielding layer is made of a material that is both electrically and thermally conductive.

[0010] Optionally, the electrode patch further includes at least one signal amplification layer, wherein at least one signal amplification layer is disposed between the shielding layer and the flexible substrate, and at least one signal amplification layer is electrically connected to the EEG electrode layer. Optionally, the flexible substrate includes a first substrate having a first degree of flexibility and a second substrate having a second degree of flexibility, the second degree of flexibility being lower than the first degree of flexibility. The second substrate is embedded in the first substrate, the first substrate being used to adhere to the scalp, and at least one of the signal amplification layers is disposed on the second substrate. Optionally, the first frequency range is 0.5Hz≦f1≦100Hz, and the second frequency range is 50kHz≦f2≦500kHz.

[0011] Optionally, the EEG electrode layer includes a plurality of EEG electrodes arranged in an array, and the conductive structure is disposed corresponding to at least one of the EEG electrodes.

[0012] Optionally, a biocompatible hydrogel adhesive layer is disposed on the skin-contact surface of the flexible substrate. Secondly, this application provides an electroencephalogram (EEG) signal processing system, including a low-pass filter, a control unit, an electric field generating module, a switching device, and the electrode patch described in this application. The input terminal of the low-pass filter is electrically connected to the conductive structure, and the cutoff frequency of the low-pass filter is higher than the upper limit of the first frequency range and lower than the lower limit of the second frequency range; the electric field generating module is electrically connected to the control unit and the stimulation electrode layer; The switching device is electrically connected between the conductive structure and the input terminal of the low-pass filter, and the control unit is used to control the switching device to selectively turn on or off the electrical connection between the conductive structure and the low-pass filter.

[0013] The beneficial technical effects of the technical solutions provided in this application include: The electrode patch is constructed into an integrated structure through multiple layers of stacked components: a flexible substrate, an EEG electrode layer, a shielding layer, and a stimulation electrode layer. This ensures both highly sensitive acquisition of EEG signals and effective application of therapeutic electric fields within the same area. The electrodes in the stimulation electrode layer do not directly contact the skin, avoiding direct current pathways and improving treatment safety. Furthermore, the stimulation electrode layer and the shielding layer form a capacitor, and the shielding layer and the scalp form another capacitor, which are cascaded together. These two capacitors can form an overall coupling capacitor. The overall coupling capacitor has very low impedance to high-frequency signals, allowing the electric field generated by the stimulation electrode layer to be transmitted to the scalp and deep brain tissue through the coupling capacitor. This overall coupling capacitor has high impedance to low-frequency signals, effectively blocking low-frequency currents while allowing alternating current to pass through. In operation, for example, when a high-frequency alternating voltage is applied to the electrode patch, the stimulation electrode layer generates a high-frequency alternating stimulation signal. Through capacitive coupling, a high-frequency alternating electric field is generated across two cascaded capacitors, acting on the scalp and deep brain tissue, while blocking the direct penetration of low-frequency current. Therefore, the electrode patch of this embodiment can both shield the downward electric field of the stimulation electrode from interfering with the computer electrode and ensure that the electric field of the stimulation electrode can be transmitted to the patient's scalp through capacitive coupling.

[0014] This application utilizes a multi-layered stacked structure, enabling the acquired EEG signals to reflect the neural responses in the areas directly affected by the therapeutic electric field in real time, thus improving the targeting of the treatment. The multi-layered stacked structure of the electrode patch in this application is smaller, thinner, and more discreet, significantly improving patient comfort and quality of life. It ensures that there is no direct current path between the therapeutic electrode and the human body, guaranteeing the safety of the treatment and avoiding electrolysis and skin burns.

[0015] Additional aspects and advantages of this application will be set forth in part in the description which follows, and will become apparent from the description or may be learned by practice of this application. Attached Figure Description

[0016] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein: Figure 1 A cross-sectional structural diagram of the electrode patch provided in the embodiments of this application when it does not have an insulating structure; Figure 2 A schematic cross-sectional view of the electrode patch provided in an embodiment of this application; Figure 3 A schematic cross-sectional view of the electrode patch provided in the embodiments of this application when the electrode patch does not have an insulating structure and the through hole of the electrode patch is spiral-shaped; Figure 4 A schematic cross-sectional view of the electrode patch with a spiral-shaped through hole, as provided in the embodiments of this application. Figure 5 An exploded view of the electrode patch provided in an embodiment of this application; Figure 6 A schematic diagram of the framework structure of an EEG signal processing system provided in an embodiment of this application.

[0017] Explanation of reference numerals in the attached figures 10-Electrode patch; 101-Through hole; 102-Insulating structure; 20-Switching device; 30-Low-pass filter; 40-Control unit; 50-Electric field generating module; 100 - Stimulating electrode layer; 110 - Stimulating electrode; 200 - Second insulating layer; 300 - Shielding layer; 400 - First insulating layer; 500 - EEG electrode layer; 510 - EEG electrode; 600 - Signal Amplification Layer; 700 - Second base; 800 - First base; 900-conductive structure. Detailed Implementation

[0018] The embodiments of this application are described below with reference to the accompanying drawings. It should be understood that the embodiments described below with reference to the accompanying drawings are exemplary descriptions for explaining the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions of the embodiments of this application.

[0019] Those skilled in the art will understand that, unless specifically stated otherwise, the terms "described" and "the" as used herein may also include plural forms. It should be further understood that the term "comprising" as used in this application's specification means the presence of described, integers, steps, operations, elements, and / or components, but does not exclude other features, information, data, steps, operations, elements, components, and / or combinations thereof supported by this art. The term "and / or" as used herein refers to at least one of the items defined by the term; for example, "A and / or B" can be implemented as "A," or as "B," or as "A and B."

[0020] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0021] Among related technologies, tumor electric field therapy (TEF) is a treatment method that interferes with the mitotic process of tumor cells by applying a low-intensity, mid-frequency alternating electric field. It is characterized by its non-invasiveness and high selectivity. However, existing devices typically use preset modes and lack the ability to dynamically adjust based on the patient's current physiological state, limiting the precision and safety of the treatment. Electroencephalogram (EEG) signals, as an important indicator of neural activity, contain information about the brain's response to electric field stimulation. However, traditional devices struggle to accurately acquire EEG signals while applying the therapeutic electric field, making it impossible for the acquired EEG signals to reflect the neural response in the area directly affected by the therapeutic electric field in real time. Furthermore, they cannot effectively block the direct penetration of high-frequency current during electric field conduction, resulting in low safety.

[0022] To solve the above technical problems, refer to Figure 1-6 This application provides an electrode patch 10, which includes a flexible substrate, an EEG electrode layer 500, a shielding layer 300 and a stimulation electrode layer 100 stacked sequentially, as well as a conductive structure 900.

[0023] The flexible substrate is used to be applied to the scalp of the subject. The EEG electrode layer 500 is used to collect EEG signals in the first frequency range; The stimulation electrode layer 100 is used to apply an electric field in a second frequency range; the lower limit of the second frequency range is higher than the upper limit of the first frequency range. A shielding layer 300 is disposed between the EEG electrode layer 500 and the stimulation electrode layer 100, and the shielding layer 300 is used for electrical connection with the reference electrode. The conductive structure penetrates the shielding layer 300 and is electrically connected to the EEG electrode layer 500; the conductive structure is insulated from both the shielding layer 300 and the stimulation electrode layer 100. In the working state, the stimulation electrode layer 100, the shielding layer 300 and the scalp form a cascaded capacitor, so that the stimulation electrode layer 100 applies an electric field in a capacitive coupling manner.

[0024] The electrode patch 10 is an integrated structure formed by stacking multiple layers of a flexible substrate, an EEG electrode layer 500, a shielding layer 300, and a stimulation electrode layer 100. This ensures that both high-sensitivity acquisition of EEG signals and effective application of therapeutic electric fields can be achieved within the same area. Specifically, the electrodes of the stimulation electrode layer 100 do not directly contact the skin, thus avoiding direct current pathways and improving treatment safety. Furthermore, the shielding layer 300, which is disposed in the middle, can be made of a highly conductive material and is electrically connected to the system reference electrode (e.g., the reference electrode can be grounded), effectively shielding the downward propagation of the stimulation electric field through the Faraday cage effect. Furthermore, a capacitor is formed between the stimulating electrode layer 100 and the shielding layer 300, and another capacitor is formed between the shielding layer 300 and the scalp. The two capacitors are cascaded. The two capacitors can form an overall coupling capacitor. As can be seen from Xc=1 / (2πfC), the overall coupling capacitor has a very small capacitive impedance to high-frequency signals such as 50kHz to 500kHz. The electric field generated by the stimulating electrode layer 100 can be transmitted to the scalp and deep brain tissue through the coupling capacitor. The overall coupling capacitor has a large capacitive impedance to low-frequency signals less than or equal to 100Hz, which can effectively block low-frequency current and allow alternating current to pass through. In the working state, for example, when a high-frequency alternating voltage is applied to the electrode patch 10, the stimulating electrode layer 100 generates a high-frequency alternating stimulation signal. Through capacitive coupling, a mid-frequency alternating electric field is generated on the two cascaded capacitors, which acts on the scalp and deep brain tissue and blocks the direct penetration of low-frequency current.

[0025] It should be noted that Xc is the capacitive reactance, π is pi, f is the frequency, and C is the capacitance.

[0026] Therefore, the electrode patch in this application embodiment can both shield the downward electric field of the stimulation electrode from interfering with the computer electrode and ensure that the electric field of the stimulation electrode can be transmitted to the patient's scalp through capacitive coupling.

[0027] The EEG electrode layer 500 can be connected to the signal processing unit below the shielding layer 300 through the conductive structure within the through-hole 101. The conductive structure ensures stable transmission of EEG signals and, due to its high impedance characteristics, creates a filtering effect under the influence of the high-frequency therapeutic electric field, further blocking the transmission of interference signals.

[0028] The multi-layered stacked structure of the electrode patch 10 in this application ensures that the recorded EEG signals are the real-time responses of the brain regions directly affected by the therapeutic electric field. Furthermore, compared to solutions requiring large areas of scalp and zoned placement, this application's structure is smaller, thinner, and more discreet, significantly improving patient comfort and quality of life. It also ensures there is no direct current path between the therapeutic electrodes and the body, guaranteeing treatment safety and avoiding electrolysis and skin burns.

[0029] Electrode patch 10 significantly improves the spatial accuracy and feedback precision of treatment by integrating EEG acquisition and electric field stimulation within the same area. Traditional methods typically arrange electrodes in separate zones, leading to misalignment between the treatment and monitoring areas, which in turn affects the effectiveness of feedback. This application utilizes a multi-layered stacked structure, enabling the acquired EEG signals to reflect the neural response in the area directly affected by the treatment electric field in real time, thus improving the targeting of the treatment. The shielding layer 300 and the stimulating electrode 110 suppress high-frequency interference through electrostatic shielding, ensuring clear and stable EEG signal acquisition.

[0030] The shielding layer 300 is electrically connected to the reference electrode, i.e., grounded, which can form a low-impedance equipotential surface, so that the high-frequency electric field forms a closed loop on the shielding layer 300, which can reduce the coupling interference to the underlying EEG electrode layer 500, and also provide a heat dissipation channel.

[0031] The shielding layer 300 can suppress the interference of high-frequency stimulation signals on the EEG electrode layer 500. It provides electromagnetic shielding and heat dissipation through low-impedance grounding, thereby preventing the leakage of high-frequency stimulation signals and affecting the EEG signals. It enables bidirectional filtering, where low-frequency EEG signals can pass through the shielding layer, while high-frequency stimulation signals are absorbed by the shielding layer 300.

[0032] Optionally, such as Figures 1 to 2 As shown, the electrode patch 10 further includes a first insulating layer 400, a second insulating layer 200, a through-hole 101, and an insulating structure 102. The first insulating layer 400 is disposed between the EEG electrode layer 500 and the shielding layer 300. The second insulating layer 200 is disposed between the shielding layer 300 and the stimulating electrode layer 100. The through-hole 101 sequentially penetrates the stimulating electrode layer 100, the second insulating layer 200, the shielding layer 300, and the first insulating layer 400. The insulating structure 102 covers the inner peripheral sidewall of the through-hole 101. A conductive structure fills the through-hole 101.

[0033] A capacitor C1 can be formed between the stimulating electrode layer 100 and the second insulating layer, and a capacitor C2 can be formed between the shielding layer 300 and the second insulating layer. Together, they constitute the overall coupling capacitor Ceq. Furthermore, according to Xc=1 / (2πfC), the overall coupling capacitor Ceq has a very small capacitive impedance to high-frequency signals such as 50kHz to 500kHz, allowing the electric field generated by the stimulating electrode layer 100 to be transmitted to the scalp and deep brain tissue through the coupling capacitor. This overall coupling capacitor Ceq has a very large capacitive impedance to low-frequency signals less than or equal to 100Hz, effectively blocking low-frequency currents while allowing alternating current to pass through. Specifically, if the two capacitors are C1≈200pF and C2≈300pF (typical flexible film capacitor values), the equivalent cutoff frequency is approximately fc=(C1+C2) / (2πC1C2Req), where C1 and C2 are the capacitances of the two layers of capacitors (in F), Req is the equivalent resistance of the coupling path (in Ω), and fc is the cutoff frequency (in Hz). In this way, it will strongly block signals below 1kHz and reduce the impedance of signals above 50kHz to a few ohms, thus meeting the requirements of high-frequency stimulation. The electrode patch 10 clearly defines the electrical boundaries between the EEG electrode layer 500, the shielding layer 300, and the stimulation electrode layer 100 by introducing a first insulating layer 400 and a second insulating layer 200, thereby achieving multi-layer electrical isolation in its structure. This isolation design not only ensures the signal purity between the layers of the electrode patch 10, but also constructs two capacitive channels, allowing the mid-frequency electric field applied by the stimulation electrode to penetrate the structure directly to the scalp and deep brain tissue via capacitive coupling, thus improving the therapeutic effect. The through-hole 101, as the core connection channel in this structure, passes through the stimulation electrode layer 100, the second insulating layer 200, the shielding layer 300, and the first insulating layer 400. Its inner wall is provided with a covering insulating structure 102 to ensure that the filled conductive structure does not directly contact the intermediate shielding layer 300, avoiding electrical short circuits.

[0034] The conductive structure can be made of silver paste. During operation, when a high-frequency alternating voltage is applied to the stimulation electrode, the stimulation electrode layer 100 forms a first-level capacitor with the shielding layer 300 through the second insulating layer 200, and the shielding layer 300 forms a second-level capacitor with the scalp through the first insulating layer 400. The electric field is conducted sequentially to the target tissue through the two levels of capacitors without forming a direct current path. The shielding layer 300 is electrically connected to the reference electrode, effectively absorbing most of the electric field lines and preventing the electric field from interfering with the EEG electrodes downwards. Even if a very small amount of leakage current attempts to enter along the path of the through-hole 101, it is difficult to significantly interfere with the EEG signal due to the high-frequency impedance of the insulating structure 102 and the conductive channel.

[0035] Because the structure adopts a through-hole 101 through-hole form, the interlayer interconnection wiring is greatly simplified, and the integration and reliability of the overall electrode patch 10 are improved, which is especially suitable for highly integrated miniaturized wearable devices.

[0036] The through-hole 101 not only provides multiple guarantees in terms of electrical safety and signal purity, but also works together with the first insulating layer 400 and the second insulating layer 200 to ensure that the electroencephalogram (EEG) signal can be obtained with high fidelity during treatment, further improving the clinical applicability of the electrode patch 10 of this application.

[0037] Optionally, such as Figure 3 and Figure 4As shown, the through hole 101 is spirally disposed through the stimulation electrode layer 100, the second insulating layer 200, the shielding layer 300 and the first insulating layer 400.

[0038] The through-hole 101 employs a spiral penetration structure, extending longitudinally through the multi-layer electrode stack structure from the stimulation electrode layer 100 through the second insulating layer 200, the shielding layer 300, and down to the first insulating layer 400. Unlike the straight through-hole 101, the spiral path extends vertically, significantly lengthening the equivalent length of the conductive path per unit vertical distance and effectively elongating the signal transmission path. This structure significantly improves high-frequency impedance in terms of electrical performance and effectively suppresses high-frequency electromagnetic interference propagating in the vertical direction. Due to its geometric complexity, the spiral through-hole 101 forms a filter unit with both inductance and capacitance, essentially acting as a natural low-pass filter. This effectively blocks high-frequency interference components, improving the signal-to-noise ratio of EEG signals. This structure itself achieves both filtering and conduction functions without requiring additional electronic components, optimizing the complexity of the electrode patch 10 and reducing power consumption, making it particularly suitable for medical devices with limited hardware resources.

[0039] Optionally, such as Figure 2 and Figure 5 As shown, the orthographic projection of the shielding layer 300 on the flexible substrate at least partially overlaps with the orthographic projection of the stimulation electrode 110 of the stimulation electrode layer 100 on the flexible substrate.

[0040] By setting the orthogonal projections of the shielding layer 300 and the stimulation electrode layer 100 on the flexible substrate to at least partially overlap, that is, the orthogonal projection area of ​​the shielding layer 300 on the flexible substrate can be greater than the orthogonal projection area of ​​the electrical stimulation electrode of the stimulation electrode layer 100 on the flexible substrate.

[0041] Since electric field lines always tend from high potential to low potential in space and terminate at the ground plane or equipotential surface, and the shielding layer 300, which is electrically connected to the reference electrode and structurally covers the area directly below the stimulating electrode, becomes the preferred termination surface for the electric field lines generated by the stimulating electrode. After the shielding layer 300 is electrically connected to the reference electrode, a low-impedance path is formed within the frequency range of the stimulating electrode, causing the electric field lines to preferentially flow towards the shielding layer 300 rather than diffuse to other areas. If the boundary of the stimulating electrode layer is not covered by the shielding layer 300, electric field leakage is likely to occur at the edge, forming an interference channel. By arranging the structure with at least partial overlap, electric field leakage in the edge region is reduced, thereby suppressing electric field diffusion in both the lateral and longitudinal directions.

[0042] The electric field generated by the stimulating electrode layer 100 is applied to the patient's scalp and brain tissue via capacitive coupling, through the stimulating electrode, the second insulating layer 200, the shielding layer 300, the first insulating layer 400, and the skin. Since the orthogonal projection of the shielding layer 300 precisely or primarily covers the area directly beneath the stimulating electrode, and the area below the shielding layer 300 is where the EEG electrode layer 500 is located, the integrity and purity of the EEG signal are maximized.

[0043] Optionally, such as Figure 1 As shown, the shielding layer 300 is made of a material that is both electrically and thermally conductive.

[0044] The shielding layer 300 uses materials with both high electrical conductivity and high thermal conductivity, such as rolled copper foil, electrolytic copper foil, or silver foil, which can effectively shield electromagnetic interference and effectively dissipate heat.

[0045] The conductivity of the copper foil is approximately 5.96 × 10⁻⁶. 7 S / m, silver foil is 6.30×10 7 S / m indicates that both copper and silver foils are highly conductive materials; the thermal conductivity of copper foil at room temperature is approximately 400 W·m. -1 ·K -1 The silver foil is approximately 429 W·m -1 ·K -1 Both copper foil and silver foil are materials with high thermal conductivity.

[0046] When a mid-frequency alternating voltage is applied to the stimulation electrode, the electric field lines emitted by it first encounter the opposing shielding layer 300. Due to the high conductivity of the shielding layer 300, an equipotential surface can be quickly formed, causing the electric field lines to terminate at this layer and preventing them from penetrating further downward to the EEG electrode layer 500, thus achieving electrostatic shielding.

[0047] Under the influence of a high-frequency electric field, even if some energy is converted into heat and concentrated in the shielding layer 300 region, due to the high thermal conductivity of the material, the heat will rapidly diffuse along the surface of the shielding layer 300, preventing localized accumulation at a particular electrode point or edge area. This avoids localized burns, decreased adhesion, or material fatigue caused by hot spots, allowing it to operate continuously for extended periods without thermal failure.

[0048] In addition, the thermal diffusion capability of the shielding layer 300 can indirectly protect the underlying EEG electrode layer 500, signal lines, or flexible substrate, so that the entire patch can maintain structural stability and electrical performance when facing high-frequency, high-power stimulation electric field signals.

[0049] The high thermal conductivity of the 300-layer shielding layer allows it to rapidly absorb and laterally diffuse heat generated by high-frequency coupling, parasitic current, or contact resistance during operation. This prevents localized temperature rises due to energy accumulation, thus avoiding discomfort or even skin damage caused by patch overheating. This enhances wearing safety and extends the lifespan of the patch structure and internal electronic components.

[0050] Optionally, such as Figure 1 and Figure 2 As shown, the electrode patch 10 also includes at least one signal amplification layer 600, which is disposed between the shielding layer 300 and the flexible substrate, and is electrically connected to the EEG electrode layer 500.

[0051] The signal amplification layer 600 is disposed between the shielding layer 300 and the flexible substrate. That is, the signal amplification layer 600 can be disposed between the flexible substrate and the EEG electrode layer 500, or between the EEG electrode layer 500 and the shielding layer 300.

[0052] By integrating at least one signal amplification layer 600 between the shielding layer 300 and the flexible substrate, and electrically connecting it to the EEG electrode layer 500, EEG signals, due to their weak amplitude and high source impedance characteristics, are highly susceptible to external high-frequency electric fields, cable common-mode noise, and environmental interference before amplification. By integrating the signal amplification layer 600 within the patch, amplification is achieved at the location closest to the EEG electrode layer 500, converting it into a low-impedance signal output. This significantly reduces signal attenuation, interference coupling, and crosstalk during transmission. The amplifier, positioned between the shielding layer 300 and the flexible substrate, provides electromagnetic isolation, further blocking interference from external electric field signals.

[0053] Optionally, such as Figure 1 and Figure 2 As shown, the flexible substrate includes a first substrate 800 having a first degree of flexibility and a second substrate 700 having a second degree of flexibility, the second degree of flexibility being lower than the first degree of flexibility. The second substrate 700 is embedded in the first substrate 800, the first substrate 800 being used to be applied to the scalp, and at least one signal amplification layer 600 is disposed on the second substrate 700.

[0054] The flexible substrate is composed of two materials with different degrees of flexibility. The first substrate 800 is highly flexible and is used to adhere to the user's scalp surface to achieve good conformability and wearing comfort. The second substrate 700 is less flexible, that is, more rigid. It is embedded in a specific area inside the first substrate 800 and can be used to support sensitive electronic devices such as the signal amplification layer 600, making the structure more stable.

[0055] All signal amplification layers 600 can be arranged on the second substrate 700. Its low flexibility can effectively suppress deformation and prevent the signal amplification layers 600 from being affected by external tensile, bending and other stresses, thereby avoiding solder joint breakage and chip failure of the signal amplification layers 600. The first substrate 800 covers the entire back or top surface of the patch, providing continuous flexible support for the entire patch, so that the patch can smoothly conform to the complex curvature of the human head.

[0056] This dual-substrate structure combines rigidity and flexibility, with the flexible area providing a comfortable fit and the rigid area supporting the device and improving the stability of the signal amplification layer 600. Simultaneously, the first substrate 800 and the second substrate 700 can have a gradual transition to prevent stress concentration and breakage caused by abrupt changes in flexibility.

[0057] This structure allows the amplifier chip to operate stably even under external stress interference, while the entire patch still maintains the flexibility, fit, and comfort required for wearable devices. Multiple signal amplification layers 600 chips are distributed at different locations on the head, each supported by a rigid second substrate 700.

[0058] Optionally, such as Figure 1 and Figure 2 As shown, the first frequency range is 0.5Hz≦f1≦100Hz, and the second frequency range is 50kHz≦f2≦500kHz.

[0059] By limiting the frequency range of EEG signal acquisition to 0.5Hz to 100Hz and the frequency of the therapeutic electric field application to 50kHz to 500kHz, two functionally completely isolated signals can coexist within the same electrode patch 10. Because the two signals are significantly separated in the frequency domain—the former being in the low-frequency band and the latter in the mid-to-high-frequency band—signal processing can easily and effectively distinguish between the two types of signals using filters and other methods.

[0060] The signal amplification layer 600 and low-pass filter in the EEG signal path are optimized for the 0.5Hz-100Hz frequency band, and the cutoff frequency is usually set to within 150Hz to ensure the complete acquisition capability of EEG signals and suppress all interference components above 50kHz at the same time. The stimulation electric field signal uses an alternating voltage waveform with a frequency much higher than this range, and its energy distribution is almost entirely outside the filter cutoff region, so it will not have a substantial impact on the acquisition path.

[0061] By clearly defining the first frequency range of the electroencephalogram (EEG) signal as 0.5 Hz to 100 Hz and the second frequency range of the therapeutic electric field as 50 kHz to 500 kHz, physical isolation based on frequency differences is achieved. This allows the acquisition of brain signals and the application of therapeutic electric fields to the electrode patch 10 to operate in parallel without interfering with each other.

[0062] Optionally, such as Figure 2 and Figure 5 As shown, the EEG electrode layer 500 includes a plurality of EEG electrodes 510 arranged in an array, and a conductive structure is arranged corresponding to at least one EEG electrode.

[0063] The EEG electrode layer 500 consists of multiple EEG electrodes arranged in an array on a flexible substrate. Each EEG electrode covers a different scalp area, and at least one EEG electrode 510 corresponds to a conductive structure, ensuring the independence of signal acquisition by each EEG electrode and preventing interference between the electrodes 510. The inner wall of each through-hole 101 is covered with insulating material to prevent short circuits between the conductive structure and the shielding layer 300, ensuring that electrical signals propagate only along the designated path.

[0064] While maintaining flexible fit, this system achieves high-density, multi-channel EEG signal acquisition from multiple brain regions. Each EEG electrode 510 is independently connected to the signal processing unit via a conductive structure, avoiding interference and crosstalk between channels and improving the accuracy of EEG signal acquisition. It successfully integrates complex multi-point signal paths, ensuring that each EEG electrode channel has complete and stable signal transmission capabilities. Simultaneously, the array layout of the EEG electrodes 510 facilitates standardized production and patch positioning, and can simultaneously monitor EEG activity at multiple sites within the treatment area. Alignment settings ensure that each signal pathway precisely corresponds to a single acquisition point, guaranteeing accurate acquisition.

[0065] Optionally, such as Figure 1 and Figure 2 As shown, a biocompatible hydrogel adhesive layer is provided on the skin-contact surface of the flexible substrate.

[0066] Hydrogel materials, as an adhesive medium, possess excellent electrical conductivity while achieving physical adhesion, allowing them to be stably attached to the patient's scalp surface without the need for additional glue or physical fixation devices.

[0067] The hydrogel adhesive layer, with its high water content and ion conductivity, reduces the contact impedance between the EEG electrodes and the skin, thereby improving the sensitivity of EEG signal acquisition and the efficiency of electric field coupling. The hydrogel's smooth properties allow it to conform to the complex contours of the scalp and the gaps between hairs, avoiding signal fluctuations or uneven treatment effects caused by poor adhesion. Simultaneously, its skin-friendly properties reduce the risk of skin irritation and discomfort from prolonged wear.

[0068] Secondly, such as Figure 2 and Figure 5As shown, this application provides an electroencephalogram (EEG) signal processing system, including a low-pass filter 30, a control unit 40, an electric field generating module 50, a switching device 20, and the electrode patch 10 described in the above-described embodiment. The input terminal of the low-pass filter 30 is electrically connected to the conductive structure 900, and the cutoff frequency of the low-pass filter 30 is higher than the upper limit of a first frequency range and lower than the lower limit of a second frequency range. The electric field generating module 50 is electrically connected to the control unit 40 and the stimulation electrode layer 100. The switching device 20 is electrically connected between the conductive structure 900 and the input terminal of the low-pass filter 30, and the control unit 40 is used to control the switching device 20 to selectively turn on or off the electrical connection between the conductive structure 900 and the low-pass filter 30.

[0069] The EEG signal processing system integrates a low-pass filter 30, a switching device 20, and a control unit 40 to control the frequency isolation and time separation of the signal channel, so as to ensure that the EEG acquisition and electric field application processes do not interfere with each other and operate stably.

[0070] The switching device 20 is controlled by the control unit to maintain its on / off state, dynamically switching its connection state according to the treatment rhythm during operation. Specifically, during the application of a mid-frequency therapeutic electric field (50kHz~500kHz), the control unit disconnects the switching device 20, interrupting the EEG signal pathway to prevent high-frequency stimulation signals from interfering with the acquisition of EEG signals. After the therapeutic electric field stops, the control unit waits for a dead time of several hundred microseconds to several milliseconds to ensure that transient interference has completely decayed before reclosing the switching device. After closure, the EEG signal enters a low-pass filter. The cutoff frequency of the low-pass filter is higher than the upper limit of the first frequency range and lower than the lower limit of the second frequency range, effectively blocking the high-frequency residual signals generated by the stimulation electric field, retaining only the EEG signal within the target range (0.5Hz~100Hz), and inputting it to the signal amplification layer 600 for further processing and acquisition. This enables reliable extraction of weak EEG signals in a high-interference environment, taking into account both frequency shielding and time isolation.

[0071] By introducing an EEG signal processing system consisting of a low-pass filter 30, a switching device 20, and a control unit 40, efficient frequency and time domain isolation of the stimulation electric field and the EEG signal is achieved, ensuring that high-quality neural signals can still be acquired under the background of high-intensity electric field therapy.

[0072] The low-pass filter accurately limits the signal frequency band, allowing only EEG signals from 0.5Hz to 100Hz to pass through, effectively suppressing therapeutic electric field interference from 50kHz to 500kHz and preventing high-frequency signals from entering the acquisition path. Combined with a switching device driven by the control unit, the system automatically cuts off the signal path during treatment to prevent the therapeutic electric field from directly affecting the acquisition of EEG electrodes, and quickly restores the path after interference attenuation, ensuring data continuity.

[0073] Understandably, during the treatment phase, the control unit 40 can turn off the low-pass filter 30, allowing only high-frequency stimulation signals to enter the target tissue via capacitive coupling; during the EEG signal acquisition phase, the low-pass filter 30 can be turned on, allowing low-frequency EEG signals to pass while blocking high-frequency signals. This timing switch enables dual isolation in the frequency and time domains.

[0074] The beneficial technical effects of the technical solutions provided in this application include: The electrode patch 10 is an integrated structure comprised of a flexible substrate, an EEG electrode layer 500, a shielding layer 300, and a stimulation electrode layer 100, stacked in multiple layers. This ensures that highly sensitive EEG signals can be acquired and a tumor electric field therapeutic field can be effectively applied within the same area. The electrodes of the stimulation electrode layer 100 do not directly contact the skin but act on the scalp and deep brain tissue through capacitive coupling, avoiding direct current pathways and improving treatment safety. The shielding layer 300 forms a cascade capacitor with the stimulation electrode layer 100, the EEG electrode layer 500, and the scalp, ensuring that the electric field conduction occurs only through the coupling path, blocking the direct penetration of high-frequency current. This effectively shields the downward electric field of the stimulation electrode from interfering with the computer electrode while ensuring that the electric field of the stimulation electrode can be transmitted to the patient's scalp through capacitive coupling. This application, through its multi-layered stacked structure, allows the acquired EEG signals to reflect the neural response in the area directly affected by the therapeutic electric field in real time, improving the targeting of the treatment. The multi-layered stacked structure of the electrode patch 10 is smaller, thinner, and more concealed, greatly improving the patient's wearing comfort and quality of life. This ensures that there is no direct current path between the treatment electrode and the human body, guaranteeing the safety of the treatment and avoiding electrolysis and skin burns.

[0075] The through hole 101 serves as the core connection channel in this structure. While passing through the stimulation electrode layer 100, the second insulating layer 200, the shielding layer 300, and the first insulating layer 400, its inner wall is provided with a covering insulating structure 102 to ensure that the filling conductive structure does not directly contact the intermediate shielding layer 300, thus avoiding electrical short circuits.

[0076] The spiral through-hole structure significantly improves high-frequency impedance in terms of electrical performance and effectively suppresses high-frequency electromagnetic interference propagating in the vertical direction. Due to its complex structure and geometry, the spiral through-hole 101 forms a filter unit with both inductance and capacitance, which is equivalent to a natural low-pass filter. It can block high-frequency interference components and improve the signal-to-noise ratio of EEG signals.

[0077] By setting the orthogonal projections of the shielding layer 300 and the stimulation electrode layer 100 on the flexible substrate to at least partially overlap, the electric field leakage in the edge region is reduced, thereby suppressing the electric field diffusion in both the lateral and longitudinal directions; thus maximizing the integrity and purity of the EEG signal.

[0078] The high thermal conductivity of the shielding layer 300 allows heat to spread rapidly along the surface of the shielding layer 300, preventing localized accumulation at a certain electrode point or edge area and avoiding localized burns, decreased adhesion, or material fatigue caused by hot spots.

[0079] The lower flexibility of the second substrate 700 can effectively suppress deformation and prevent the signal amplification layer 600 from being affected by external stresses such as stretching and bending, thereby avoiding solder joint breakage and chip failure of the signal amplification layer 600.

[0080] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0081] In the description of this specification, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

[0082] The above description is only a partial implementation of this application. It should be noted that for those skilled in the art, other similar implementation methods based on the technical concept of this application, without departing from the technical concept of this application, also fall within the protection scope of the embodiments of this application.

Claims

1. An electrode patch, characterized in that, include: The structure consists of a flexible substrate, an EEG electrode layer, a shielding layer, a stimulation electrode layer, and a conductive structure, all stacked in sequence. The flexible substrate is used to be applied to the scalp of the subject; The EEG electrode layer is used to collect EEG signals in a first frequency range; The stimulation electrode layer is used to apply an electric field in a second frequency range; The lower limit of the second frequency range is higher than the upper limit of the first frequency range; A shielding layer is disposed between the EEG electrode layer and the stimulation electrode layer, and the shielding layer is used for electrical connection with the reference electrode. The conductive structure penetrates the shielding layer and is electrically connected to the EEG electrode layer; the conductive structure is insulated from both the shielding layer and the stimulation electrode layer. In operation, the stimulation electrode layer, the shielding layer, and the scalp form a cascaded capacitor, so that the stimulation electrode layer applies an electric field in a capacitively coupled manner.

2. The electrode patch according to claim 1, characterized in that, Also includes: A first insulating layer is disposed between the EEG electrode layer and the shielding layer; A second insulating layer is disposed between the shielding layer and the stimulating electrode layer; The through-hole sequentially penetrates the stimulation electrode layer, the second insulating layer, the shielding layer, and the first insulating layer; An insulating structure covers the inner peripheral sidewall of the through hole; The conductive structure fills the through hole.

3. The electrode patch according to claim 2, characterized in that, The through-hole is spirally disposed through the stimulation electrode layer, the second insulating layer, the shielding layer and the first insulating layer.

4. The electrode patch according to claim 1, characterized in that, The orthographic projection of the shielding layer onto the flexible substrate at least partially overlaps with the orthographic projection of the stimulation electrode of the stimulation electrode layer onto the flexible substrate.

5. The electrode patch according to claim 1, characterized in that, The shielding layer is made of a material that is both electrically and thermally conductive.

6. The electrode patch according to claim 1, characterized in that, It also includes at least one signal amplification layer, wherein at least one of the signal amplification layers is disposed between the shielding layer and the flexible substrate, and at least one of the signal amplification layers is electrically connected to the EEG electrode layer.

7. The electrode patch according to claim 6, characterized in that, The flexible substrate includes a first substrate having a first degree of flexibility and a second substrate having a second degree of flexibility, the second degree of flexibility being lower than the first degree of flexibility, the second substrate being embedded in the first substrate, the first substrate being used to adhere to the scalp, and at least one of the signal amplification layers being disposed on the second substrate.

8. The electrode patch according to claim 1, characterized in that, The first frequency range is 0.5Hz≦f1≦100Hz, and the second frequency range is 50kHz≦f2≦500kHz.

9. The electrode patch according to claim 2, characterized in that, The EEG electrode layer includes a plurality of EEG electrodes arranged in an array, and the conductive structure is arranged corresponding to at least one of the EEG electrodes.

10. The electrode patch according to claim 1, characterized in that, A biocompatible hydrogel adhesive layer is provided on the skin-contact surface of the flexible substrate.

11. A brainwave signal processing system, characterized in that, Includes a low-pass filter, a control unit, an electric field generating module, a switching device, and an electrode patch as described in any one of claims 1 to 10; The input terminal of the low-pass filter is electrically connected to the conductive structure, and the cutoff frequency of the low-pass filter is higher than the upper limit of the first frequency range and lower than the lower limit of the second frequency range. The electric field generating module is electrically connected to the control unit and the stimulation electrode layer; The switching device is electrically connected between the conductive structure and the input terminal of the low-pass filter, and the control unit is used to control the switching device to selectively turn on or off the electrical connection between the conductive structure and the low-pass filter.

Images