Multilayer flexible electrode
By using an alternating stacked structure of multiple flexible electrodes, the problems of low duty cycle and low volume utilization in existing physiological electrode systems are solved, achieving high-density signal acquisition and electrode site independence, and improving electrode flexibility and application efficiency.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- HARBIN INSTITUTE OF TECHNOLOGY (SHENZHEN) (INSTITUTE OF SCIENCE AND TECHNOLOGY INNOVATION HARBIN INSTITUTE OF TECHNOLOGY SHENZHEN)
- Filing Date
- 2026-03-26
- Publication Date
- 2026-04-28
AI Technical Summary
Existing physiological electrode systems have low duty cycles and low volume utilization, which limits their application in limited or narrow spaces.
A multi-layer flexible electrode structure is adopted, which forms a stepped stacked structure by alternately stacking flexible conductive films and insulating films. The length of each conductive film decreases sequentially. The central area of the conductive film is covered by the insulating film, and the edge area serves as the electrode point, forming an independent electrode unit, thereby improving the number of channels and integration.
It significantly improves the volume utilization, duty cycle, and number of channels of the electrodes, enhances flexibility and adaptability, reduces interference between conductive films, and improves the efficiency and accuracy of signal acquisition and stimulation.
Smart Images
Figure CN224166309U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of electronic device technology, and in particular to a multilayer flexible electrode. Background Technology
[0002] Physiological electrodes can come into contact with the human body or other biological tissues to collect biosignals, apply stimulation, or perform other related functions. With the development of flexible electronics technology, physiological electrodes face increasingly stringent requirements for spatial resolution, channel count, and device miniaturization in applications such as wearable medical devices, implantable diagnostics, and human-computer interaction.
[0003] However, most existing electrode systems employ a two-dimensional planar structure, with each electrode unit and its corresponding fan-out conductor sharing the same flexible substrate. This results in wiring occupying a significant portion of the device area, leading to a low proportion of the area actually used for signal acquisition or stimulation (electrode duty cycle) and a limited number of channels. Furthermore, the overall device size needs to be significantly increased to accommodate the complex wiring, thus limiting its application in confined or narrow spaces. Summary of the Invention
[0004] The purpose of this application is to provide a multilayer flexible electrode, which aims to solve the problems of low duty cycle and low volume utilization of physiological electrodes in the prior art.
[0005] To achieve the above-mentioned objectives, the technical solution adopted in this application is as follows:
[0006] This application provides a multilayer flexible electrode, comprising two or more strip-shaped flexible conductive films and two or more strip-shaped flexible insulating films;
[0007] Flexible conductive films and flexible insulating films are stacked alternately in sequence, and along the thickness direction from one end face to the other end face of the multilayer flexible electrode, the length of each film (including both types of films) decreases sequentially, forming a stepped stacked structure. The middle area of each flexible conductive film is covered by the next flexible insulating film, while the edge area along the length direction of the flexible conductive film is not covered by the next flexible insulating film.
[0008] This application presents a multilayer flexible electrode constructed by alternating layers of strip-shaped flexible conductive films and flexible insulating films. The flexible insulating films separate adjacent flexible conductive films, allowing each layer to function as an independent electrode unit without interference from adjacent layers. Furthermore, the central region of the flexible conductive films is covered while the edge regions are uncovered, creating a structure where the center is encapsulated and the edges serve as electrode points. This multilayer structure increases the number of channels. Additionally, the progressively decreasing length of each film layer along the thickness direction creates a stepped stacked structure that exposes the uncovered edge regions, allowing the electrode points to be arranged sequentially along the thickness direction without interference. Moreover, the flexibility of each film layer results in a multilayer flexible electrode that adapts to the shape of the object being tested, fully utilizing all electrode points. In summary, compared with the existing two-dimensional planar electrode system where electrode points occupy each other's space and are prone to mutual interference, this application extends the multilayer flexible electrode to a three-dimensional stacked architecture. By introducing multiple layers of flexible conductive film in the thickness direction, the conductive components that originally occupied the planar area can be transferred to the vertical dimension, thereby significantly improving the volume utilization, electrode duty cycle, number of channels, and overall integration.
[0009] Optionally, the length of the flexible conductive film is 0.4 mm to 40 mm longer than the length of the subsequent flexible insulating film. This allows for the use of edge regions along the length as electrode sites, further improving volume utilization, electrode duty cycle, channel count, and overall integration. It also facilitates the encapsulation of the central region of the flexible conductive film, protecting it, reducing interference between adjacent conductive films, and improving the long-term reliability of the multilayer flexible electrode. In the example, the edges at both ends can be extended by 0.2 mm to 20 mm to form usable electrode sites on both sides.
[0010] Optionally, the length of the flexible insulating film is 0.4 mm to 40 mm longer than the length of the subsequent flexible conductive film, which helps to form a support at the bottom of the flexible conductive film and fully support the flexible conductive film.
[0011] Optionally, the edge region along the length of the flexible conductive film includes both ends of the flexible conductive film. This structural arrangement ensures that both ends of each flexible conductive film layer are not covered along the length and can serve as electrode sites, further improving the duty cycle, channel number, and integration density of the electrodes.
[0012] Optionally, electrodes or pads are provided on the edge region along the length of the flexible conductive film. The electrodes can collect electrical signals, and the pads can be electrically connected to external circuits, enabling the flexible conductive film to function as a physiological electrode.
[0013] Optionally, the length of the flexible conductive film is 0.3 cm to 20 cm. Optionally, the length of the flexible insulating film is 0.3 cm to 22 cm. This length range allows the multilayer flexible electrode to be adapted to different sizes of the object being tested, making it suitable for a wider range of applications.
[0014] Optionally, the thickness of the flexible conductive film is 20 μm to 200 μm. Optionally, the thickness of the flexible insulating film is 0.4 μm to 20 μm. This thickness range allows the multilayer flexible electrode to balance conductivity stability and mechanical flexibility, and effectively reduces the overall device thickness while meeting functional requirements, which is beneficial for improving volume utilization and achieving high-density signal acquisition. These thicknesses refer to the thickness of the flexible conductive film and the flexible insulating film itself. If the edge region of the flexible insulating film in the width direction adheres to the edge region of another adjacent flexible insulating film in the width direction, its thickness may not be the same as the thickness of its body.
[0015] Optionally, the width of the flexible conductive film is smaller than the width of the flexible insulating film, and the edge regions on both sides of the width direction of adjacent flexible insulating films are combined with each other. Since the flexible insulating film is flexible, when its width is greater than that of the flexible conductive film, the edge regions on both sides of the width direction can naturally wrap around the flexible conductive film and form a lateral encapsulation with the adjacent flexible insulating film, effectively protecting each flexible conductive film and improving the long-term reliability of the multilayer flexible electrode.
[0016] Optionally, the width of the flexible conductive film is 0.3 cm to 20 cm. Optionally, the width of the flexible conductive film is 0.4 mm to 100 mm narrower than that of the flexible insulating film. These parameters further facilitate the encapsulation of the flexible conductive film by the flexible insulating film in the width direction, further effectively protecting each flexible conductive film and improving the long-term reliability of the multilayer flexible electrode.
[0017] Optionally, each flexible conductive film has the same width. This design helps to precisely align the flexible conductive films in the width direction, improving the consistency and stability of signal acquisition by the multi-layer flexible electrodes.
[0018] Optionally, each flexible insulating film has the same width. This design helps maintain high consistency and reliability of the packaging structure in the width direction, and improves the structural stability of the multilayer flexible electrode.
[0019] Optionally, along the thickness direction, the area of each film layer decreases sequentially, with the area of the next film layer being 35% to 82% of the area of the previous film layer. This degree of area reduction allows the flexible conductive film to have suitable edge areas left in the length direction as electrode points. At the same time, the flexible insulating film can effectively cover the middle area of the previous flexible conductive film layer and effectively support the entire subsequent flexible conductive film layer, further improving the duty cycle, channel number, and integration density of the electrodes.
[0020] Optionally, the multilayer flexible electrode is truncated trapezoidal in shape with an equivalent slope greater than 0° and less than or equal to 10°. This truncated trapezoidal structure and slope further improve the duty cycle and integration of the electrode, and can better adapt to deformation when the multilayer flexible electrode is attached to the object under test.
[0021] Optionally, both ends of the multilayer flexible electrode are flexible insulating films. These flexible insulating films, forming the outermost layer, protect the multilayer flexible electrode and improve long-term reliability.
[0022] Optionally, the flexible conductive film has 1 to 20 layers. Optionally, the flexible insulating film has 2 to 21 layers. This multilayer flexible electrode of flexible conductive film or flexible insulating film has a high number of channels, which can improve signal acquisition density. Attached Figure Description
[0023] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0024] Figure 1 This is a side view of the structure of adjacent flexible conductive films and flexible insulating films in the multilayer flexible electrode of Embodiment 1 of this application;
[0025] Figure 2 This is a top view schematic diagram of the adjacent flexible conductive film and flexible insulating film in the multilayer flexible electrode of Embodiment 1 of this application;
[0026] Figure 3 This is a schematic diagram of the fabrication process of the multilayer flexible electrode in Embodiment 1 of this application;
[0027] Figure 4 This is a schematic diagram of the multilayer flexible electrode connection wire method in Embodiment 1 of this application;
[0028] Figure 5 This is a schematic diagram of the multilayer flexible electrode of Embodiment 1 of this application attached near the wrist;
[0029] Figure 6 This is a schematic diagram showing the response of a person's index finger, middle finger, and thumb when the multilayer flexible electrode of Embodiment 1 of this application emits a stimulation signal;
[0030] Figure 7 This is a comparison diagram showing the number of electrode points that can be assigned to each finger between the multilayer flexible electrode of Embodiment 1 of this application and the standard medical hydrogel electrode;
[0031] Figure 8 This is a comparison chart of the activation threshold current of the multilayer flexible electrode of Embodiment 1 of this application and the standard medical hydrogel electrode;
[0032] The attached figures are labeled as follows:
[0033] 1-Flexible conductive film; 2-Flexible insulating film. Detailed Implementation
[0034] To make the technical problems, technical solutions, and beneficial effects of this application clearer, the following detailed description is provided in conjunction with embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.
[0035] In this application, the term "and / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects have an "or" relationship.
[0036] In this application, "at least one" means one or more, and "multiple" means two or more. "At least one of the following" or similar expressions mean any combination of these items, including any combination of single or multiple items.
[0037] Example 1
[0038] This embodiment provides a multilayer flexible electrode. Please refer to [link / reference]. Figure 1 , Figure 2 The multilayer flexible electrode comprises alternating layers of flexible conductive film 1 and flexible insulating film 2, totaling 10 layers of flexible conductive film 1 and 11 layers of flexible insulating film 2, with the bottom and top layers being flexible insulating film 2. The thickness of each flexible insulating film 2 is 20 μm and the width is 10 mm, while the thickness of each flexible conductive film 1 is 60 μm and the width is 5 mm. In the width direction, all flexible conductive films 1 and all flexible insulating films 2 are aligned. Since each flexible insulating film 2 is wider than the flexible conductive film 1, the edges of the flexible insulating films 2 adhere to adjacent flexible insulating films 2. Furthermore, the length of each film decreases from bottom to top, forming a stepped stacked structure. Each flexible conductive film 1 is completely supported by the next layer of flexible insulating film 2, and its middle area is covered by the previous layer of flexible insulating film 2, while the edge areas are exposed as electrode sites. The bottom flexible insulating film 2 has a length of 105 mm, and the subsequent flexible conductive film 1 has a length of 100 mm; the top flexible insulating film 2 has a length of 22 mm, and the flexible conductive film 1 encapsulated within it has a length of 30 mm.
[0039] Figure 1 This is a side view of the four flexible conductive films 1 and the adjacent five flexible insulating films 2, that is, a schematic diagram from the width direction to the length direction. Figure 1 It is mainly used to show the combination relationship between the two rather than to show the specific size ratio. It can be seen that each flexible conductive film 1 is partially encapsulated by two layers of flexible insulating film 2. The edge area of each flexible insulating film 2 in the width direction is adhered to the edge area of the adjacent flexible insulating film 2 in the width direction. Figure 2 This is a side view schematic diagram of one layer of flexible conductive film 1 and two adjacent layers of flexible insulating film 2. Figure 2 The primary purpose is to illustrate the bonding relationship between the two layers, rather than to demonstrate specific size ratios. It can be seen that each layer of flexible conductive film 1 is partially encapsulated by the upper flexible insulating film 2, with the central area covered and the edge areas exposed. Each layer of flexible conductive film 1 is also supported and held in place by the lower flexible insulating film 2. This process continues, with each lower layer becoming longer, until the multilayer flexible electrode of Example 1 is obtained.
[0040] Because each layer of the flexible insulating film is very thin, direct assembly in the air easily leads to wrinkles, self-adhesion, and curling, resulting in a low yield. Therefore, traditional methods cannot be used. Please refer to [reference needed]. Figure 3 In this embodiment, the multilayer flexible electrode is assembled according to the following steps S1 to S5:
[0041] S1: Prepare a flexible insulating film.
[0042] First, the glass substrate was subjected to plasma surface activation treatment. Then, a sodium polystyrene sulfonate (PSSNa) solution was spin-coated onto the glass substrate surface, followed by heating and annealing to form a water-soluble sacrificial layer. An insulating polymer solution, optionally including a styrene-ethylene-butene-styrene block copolymer (SEBS) solution, was spin-coated over the sacrificial layer. This was then cured by heating to obtain a flexible insulating film attached to the sacrificial layer on one side of the glass substrate. A total of 11 samples were prepared.
[0043] S2: The bottom layer of the multilayer flexible electrode structure:
[0044] A composite film formed by nano-silver and polymer is cut into lead-like shapes to serve as a flexible conductive film. Then, one sample from step S1 is taken, and the flexible conductive film is attached to the surface of a flexible insulating film to form a conductive circuit according to the designed circuit layout. Subsequently, the flexible conductive film and the flexible insulating film are subjected to hot-pressing treatment at a temperature of 300 ℃ and a pressure of 2000 Pa for 30 s to ensure a firm bond between the flexible conductive film and the flexible insulating film, ensuring the mechanical stability and conductive continuity of the circuit, serving as the bottom layer of the entire multilayer flexible electrode.
[0045] S3: Temporary fixed flexible insulating film.
[0046] For the remaining 10 samples from step S1, a polyethylene terephthalate (PET) support frame was placed around the flexible insulating membrane, and secured with polyimide (PI) tape. The samples were then placed in deionized water to dissolve the water-soluble sacrificial layer, allowing the flexible insulating membrane to detach from the glass substrate and float on the surface. In the aquatic environment, the floating flexible insulating membrane was adhered to a commercially available polytetrafluoroethylene (PTFE) self-supporting membrane. The entire structure was then lifted out of the water and air-dried at room temperature. The support frame and self-supporting membrane maintained the flatness of the flexible insulating membrane.
[0047] S4: Begin constructing a multilayer flexible electrode.
[0048] The flexible insulating film from step S3 is cut, and then the cut flexible insulating film is placed over the flexible conductive film from step S2. The cut flexible insulating film is shorter in length, allowing it to completely cover the central area of the flexible conductive film while exposing the edges as electrode sites. A hot-pressing process is then performed at 300 °C and 2000 Pa for 30 seconds, ensuring a strong bond between the flexible insulating film and the underlying flexible conductive film. Furthermore, because SEBS has self-adhesive properties and is flexible, it can deform. This flexible insulating film is wider than the flexible conductive film in the width direction, so its edge areas adhere firmly to and bond with the edge areas of the bottom flexible insulating film in the width direction. The PTFE intermediate substrate is then removed, completing the construction of the second flexible insulating film.
[0049] S5: Repeat and build the entire multilayer flexible electrode.
[0050] Continue by covering the second flexible insulating film in step S4 with a shorter flexible conductive film, and then hot-pressing it according to the hot-pressing parameters of step S2. Then, cover the third flexible insulating film with an even shorter film in the same manner as in step S4, and so on. Continue until 10 flexible conductive films have been formed and the top flexible insulating film is encapsulated. Finally, place the bottom of the device in water. This will dissolve the sacrificial layer at the very bottom of steps S1 and S2, and the glass substrate will separate from the multilayer flexible electrodes, resulting in a multilayer flexible electrode.
[0051] Example 2
[0052] This embodiment provides a multilayer flexible electrode. The only difference between this multilayer flexible electrode and Embodiment 1 is that it has a total of 7 flexible conductive films and 8 flexible insulating films, and the decreasing length of each layer is higher than that of Embodiment 1; all other aspects are the same.
[0053] Example 3
[0054] This embodiment provides a multilayer flexible electrode. The only difference between this multilayer flexible electrode and Embodiment 1 is that it has a total of 4 flexible conductive films and 5 flexible insulating films, and the decreasing length of each layer is greater than that of Embodiments 1 and 2. All other aspects are the same.
[0055] Example 4
[0056] This embodiment provides a multilayer flexible electrode. The only difference between this multilayer flexible electrode and Embodiment 1 is that it has a total of 15 flexible conductive films and 16 flexible insulating films, and the decreasing length of each layer is lower than that of Embodiment 1; all other aspects are the same.
[0057] Example 5
[0058] This embodiment provides a multilayer flexible electrode. The only difference between this multilayer flexible electrode and Embodiment 1 is that it has a total of 20 flexible conductive film layers and 21 flexible insulating film layers, and the decreasing length of each layer is lower than that of Embodiment 1; all other aspects are the same.
[0059] In terms of preparation method, compared with Example 1, not only were the number of film layers and length adjusted, but also some processes were modified. In step S1, instead of preparing 11 samples, only one sample was prepared for step S2, and a large-area flexible insulating film was prepared. This large-area flexible insulating film was temporarily fixed in step S3, and then cut into 20 samples in step S4. These 20 samples were used to construct a multilayer flexible electrode in accordance with the method of step S4.
[0060] Example 6
[0061] This embodiment provides a multilayer flexible electrode. The only difference between this multilayer flexible electrode and Embodiment 1 is that the styrene-ethylene-butene-styrene block copolymer (SEBS) is replaced with polydimethylsiloxane (PDMS). Simultaneously, the length of the bottom flexible insulating film is changed to 150 mm, the subsequent flexible conductive film length is 143 mm, the top flexible insulating film length is 40 mm, and the length of the encapsulated flexible conductive film is 42 mm. The decreasing length of each layer is adjusted accordingly, while all other aspects remain the same.
[0062] Example 7
[0063] This embodiment provides a multilayer flexible electrode. The only difference between this multilayer flexible electrode and Embodiment 1 is that the styrene-ethylene-butene-styrene block copolymer (SEBS) is replaced with Parylene, and the spin coating method is replaced with vapor deposition. Simultaneously, the width of each layer decreases from bottom to top; the width of the bottom flexible insulating film is 20 mm, the width of the subsequent flexible conductive films is 10 mm, and the width of the top flexible insulating film remains 10 mm, while the width of the encapsulated flexible conductive film remains 5 mm. Therefore, only the width of each intermediate layer decreases; everything else remains the same.
[0064] Performance testing and application of multilayer flexible electrodes.
[0065] 1. The multilayer flexible electrodes in the above embodiments exhibit significant advantages in transcutaneous electroneurostimulation (TENS) applications. Due to their high electrode density and finer spatial distribution, they can more accurately cover and match the target neural region within a limited adhesion area, achieving precise control over different motor functions. Experimental results show that, compared to standard medical hydrogel electrodes, multilayer flexible electrodes have more effective activation electrode sites and significantly reduce the stimulation threshold current while achieving motor activation, thereby improving stimulation resolution while enhancing the safety and comfort of the stimulation process.
[0066] Specifically, the multilayer flexible electrodes in Examples 1 to 7 can be used for transcutaneous nerve stimulation and rehabilitation assistance. By attaching the multilayer flexible electrodes to target areas such as the forearm, hand, or leg, selective electrical stimulation of specific nerves can be achieved. The high electrode density and fine arrangement allow for precise independent activation of single muscle groups within a limited attachment area, assisting rehabilitation training or improving functional recovery in patients with movement disorders. Simultaneously, the low stimulation threshold current enhances safety and comfort.
[0067] The schematic diagram of the external wire of the multilayer flexible electrode with 10 layers of flexible conductive film in Example 1 is shown below. Figure 4 As shown. Figure 4 In this multilayer flexible electrode, there are two ends along its length. One end serves as the front electrode point, which can contact the skin, and the other end serves as the rear end, where a wire can be bonded. Each layer of flexible conductive film is independently connected to a wire, and then numerically encapsulated. The wire can be connected to an external instrument, which can be a signal acquisition device or a device that applies stimulation signals.
[0068] The device is worn on the surface of the human body as follows: Figure 5 As shown, the multilayer flexible electrode has a shorter top surface and a longer bottom surface in the thickness direction. The shorter top surface is aligned with the skin surface, and the electrode points at the front end are attached to the skin. For example... Figure 5The device is placed near the wrist and then bent to conform to the shape of the limb, allowing the electrode points of each flexible conductive film to contact the skin. This results in high volume utilization, high electrode duty cycle, and high overall integration. Because the thickness of the multi-layer flexible electrodes decreases sequentially from the bottom to the top (i.e., increases sequentially from the top to the bottom), these electrode points are covered by the underlying flexible insulating film, reducing interference from the external environment.
[0069] Please refer to Figure 6 Because each flexible conductive film has an independent wire connected to its rear end, and the electrode points at the front end of each flexible conductive film are attached to the skin surface, applying different stimulation signals to different wires can achieve stimulation effects on different fingers. For example... Figure 6 Stimulating the index finger will cause it to lift; stimulating the middle finger will cause it to lift; stimulating the thumb will cause it to extend.
[0070] Because the multilayer flexible electrode of Example 1 has high volume utilization, high electrode duty cycle, and high overall integration, the same electrode area can accommodate more electrode points. This allows for the allocation of more electrode sites to different finger stimulation areas, enabling the programming of different stimulation signal schemes and better control of the electrical stimulation program on the finger. For example... Figure 7 In Example 1, the multilayer flexible electrode can assign 4 electrode points to the thumb, 3 to the index finger, 2 to the middle finger, and 1 to the little finger. In contrast, existing standard medical hydrogel electrodes can only assign 2 to the thumb, 1 to the index finger, 0 to the middle finger, and 1 to the little finger. Clearly, compared to the standard medical hydrogel electrode, the multilayer flexible electrode of Example 1 can assign more electrode points to the fingers.
[0071] A comparative experiment on the threshold current for activating hand movements using the multilayer flexible electrode of Example 1 and the standard medical hydrogel electrode revealed that the threshold current for activating finger movements using the multilayer flexible electrode of Example 1 was lower than that of the medical electrode. Figure 8 As shown, the multilayer flexible electrode of Example 1 can more easily activate the target nerves in the finger, achieving stimulation with a smaller current.
[0072] 2. The multilayer flexible electrodes in the above embodiments can also be applied to high-resolution physiological signal acquisition. Multilayer flexible electrodes can be used for electrocardiogram (ECG), electromyography (EMG), or other electrophysiological signal acquisition. Because the conductive lines are vertically integrated and do not interfere with each other, high-channel-count acquisition can be achieved within a limited area, improving signal spatial resolution and signal-to-noise ratio, and providing a high-precision data foundation for physiological monitoring, brain-computer interfaces, or motion control systems.
[0073] 3. The multilayer flexible electrodes in the above embodiments can also be applied to in vivo implantable neural interfaces. Multilayer flexible electrodes can be used in miniaturized, minimally invasive in vivo implantable interfaces, such as those in the spinal cord, peripheral nerves, or on the surface of the cerebral cortex. Through high-density vertically integrated electrode sites, precise stimulation and recording of target nerves or brain regions can be achieved, while reducing implantation volume and the risk of tissue damage, providing a high-channel, high-precision solution for neural modulation, brain-computer interfaces, and implantable rehabilitation therapy.
[0074] 4. The multilayer flexible electrodes in the above embodiments can also be applied to human-machine interfaces and smart wearable devices. Integrating multilayer flexible electrodes into wearable devices, such as gloves, armbands, or patches, enables high-precision capture of finger movements or muscle group motions, which can be used in virtual reality, robot control, or intelligent assistive devices. The matching of high-density electrode positions with target muscle groups or neuroanatomical structures makes the operation feedback more refined and natural, while ensuring wearing comfort.
[0075] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.
Claims
1. A multilayer flexible electrode, characterized in that: It includes two or more strip-shaped flexible conductive films and two or more strip-shaped flexible insulating films; The flexible conductive film and the flexible insulating film are stacked alternately in sequence, and the length of each film decreases sequentially along the thickness direction from one end face to the other end face of the multilayer flexible electrode, forming a stepped stacked structure. The middle area of each layer of the flexible conductive film is covered by the next layer of the flexible insulating film, while the edge area of the flexible conductive film along its length direction is not covered by the next layer of the flexible insulating film.
2. The multilayer flexible electrode according to claim 1, characterized in that: The length of the flexible conductive film is 0.4 mm to 40 mm longer than the length of the subsequent flexible insulating film; and / or, The length of the flexible insulating film is 0.4 mm to 40 mm longer than the length of the subsequent flexible conductive film.
3. The multilayer flexible electrode according to claim 1 or 2, characterized in that: The edge region along the length of the flexible conductive film includes both ends of the flexible conductive film; and / or, Electrodes or pads are provided on the edge region along the length of the flexible conductive film.
4. The multilayer flexible electrode according to claim 1 or 2, characterized in that: The length of the flexible conductive film is 0.3 cm to 20 cm; and / or, The length of the flexible insulating film is 0.3 cm to 22 cm.
5. The multilayer flexible electrode according to claim 1 or 2, characterized in that: The thickness of the flexible conductive film is 20 μm to 200 μm; and / or, The thickness of the flexible insulating film is 0.4 μm to 20 μm.
6. The multilayer flexible electrode according to claim 1 or 2, characterized in that: The width of each flexible conductive film is smaller than the width of the flexible insulating film, and the edge regions on both sides of the width direction of two adjacent flexible insulating films are joined together; and / or, The width of the flexible conductive film is 0.3 cm to 20 cm; and / or, The flexible conductive film is 0.4 mm to 100 mm narrower than the flexible insulating film.
7. The multilayer flexible electrode according to claim 1 or 2, characterized in that: Each layer of the flexible conductive film has the same width; and / or, Each layer of the flexible insulating film has the same width.
8. The multilayer flexible electrode according to claim 1 or 2, characterized in that: Along the thickness direction, the area of each film layer decreases sequentially, with the area of each subsequent film layer being 35% to 82% of the area of the preceding film layer; and / or, The multilayer flexible electrode is truncated trapezoidal in shape, with an equivalent slope greater than 0° and less than or equal to 10°.
9. The multilayer flexible electrode according to claim 1 or 2, characterized in that: Both ends of the multilayer flexible electrode are flexible insulating films.
10. The multilayer flexible electrode according to claim 1 or 2, characterized in that: The flexible conductive film has 1 to 20 layers; and / or, The flexible insulating film has 2 to 21 layers.