Pressure sensing array based on discrete structure and preparation method thereof

Abstract

The invention discloses a pressure sensing array based on a discretization structure and a preparation method thereof. The pressure sensing array comprises a lower substrate; the conducting layer is arranged on the lower substrate; the discretization sensing layer comprises a plurality of independent sensing units, and the plurality of sensing units are arranged on the conductive layer and are arranged in an array; and a gap is formed between every two adjacent sensing units. Compared with a traditional structure that an upper electrode thin film is continuously laid, even if the upper electrode thin film only bears local pressure, the whole thin film can be tensioned, so that adjacent pixels are deformed, and signal crosstalk is caused; according to the invention, each sensing unit is independent, the sensing units are separated through physical gaps, are not contacted and linked, and clearly distinguish adjacent pressure points, and the pressure only acts on the sensing unit and does not diffuse around, so that the mechanical stress cannot be transmitted across the units, the local pressure does not cause the response of surrounding pixels any more, and the reliability of the sensor is improved. Therefore, mechanical crosstalk is avoided.

Description

Technical Field

[0001] This application relates to the field of sensor technology, and in particular to a pressure sensing array based on a discrete structure and its fabrication method. Background Technology

[0002] Pressure sensor arrays, as a key component capable of sensing the distribution of external pressure, are widely used in smart wearable devices, smart robot systems, and medical monitoring equipment to achieve pressure sensing capabilities similar to human touch, thereby supporting interaction and complex operations between devices and the environment.

[0003] Existing pressure sensor arrays generally employ a "sandwich structure," consisting of an upper electrode layer, a lower electrode layer, and a sensing layer positioned between them. The upper electrode layer is typically a continuous thin-film structure carrying the circuitry. Due to the continuously tensioned surface characteristics of this upper electrode layer, when pressure is applied to a localized area, the pressure is transmitted through the continuous thin film to the surrounding areas. This causes the pressure cells in the surrounding areas to simultaneously generate electrical signal changes, thus interfering with the target pressure signal and creating a mechanical crosstalk problem.

[0004] Therefore, existing technologies still need to be improved and developed. Summary of the Invention

[0005] The technical problem to be solved by this application is to provide a pressure sensing array based on a discrete structure and its fabrication method, which addresses the above-mentioned deficiencies of the prior art and aims to solve the problem of mechanical crosstalk in the prior art.

[0006] The technical solution adopted by this application to solve the technical problem is as follows: A pressure sensing array based on a discretized structure, comprising: Lower base; A conductive layer is disposed on the lower substrate; The discrete sensing layer includes multiple independent sensing units, which are disposed on the conductive layer and arranged in an array; there is a gap between each pair of adjacent sensing units.

[0007] The pressure sensing array based on a discrete structure, wherein the conductive layer comprises: Multiple row electrodes; Multiple column electrodes; multiple column electrodes and multiple row electrodes are arranged perpendicularly to each other to form an addressing matrix with multiple addressing units; the sensing unit corresponds one-to-one with the addressing unit.

[0008] The pressure sensing array based on a discrete structure, wherein the conductive layer further includes: A curved electrode is disposed within the addressing unit and is connected to the row electrode and column electrode corresponding to the addressing unit, respectively; the sensing unit is disposed on the curved electrode.

[0009] The pressure sensing array based on a discrete structure, wherein the conductive layer further includes: An insulating portion is disposed between the row electrode and the column electrode, and located at the intersection between the row electrode and the column electrode.

[0010] The pressure sensing array based on a discrete structure, wherein the row electrodes and the column electrodes are both attached to the lower substrate.

[0011] The pressure sensing array based on a discretized structure, wherein the sensing unit comprises: Sensing microstructures for electrical connection to the conductive layer; A microstructure support frame is disposed outside the sensing microstructure and encloses the sensing microstructure.

[0012] The pressure sensing array based on a discrete structure, wherein the sensing microstructure is a pyramid-shaped, hemispherical, conical, wave-shaped, or micro-dome-shaped microstructure.

[0013] The pressure sensing array based on a discrete structure, wherein the material of the lower substrate is one or more of PDMS, SEBS, ECOFLEX, polyurethane, and polyimide.

[0014] A method for fabricating a pressure sensing array based on a discretized structure as described in any one of the above methods, comprising the following steps: On the upper surface of the lower substrate, multiple row electrodes, insulating portions covering the row electrodes, and multiple column electrodes covering the insulating portions are sequentially formed layer by layer using a mask pattern deposition process to construct a substrate with an addressing matrix. Conductive ink is molded into a single sensing microstructure sheet, and then cured and demolded. The sensing microstructure sheet is segmented to obtain multiple independent sensing microstructures; An elastomer material is cast onto the surface of the sensing microstructure and then cured to obtain multiple independent sensing units. The sensing units are attached one-to-one with the addressing units of the addressing matrix on the substrate, and the sensing units are connected to the corresponding row electrodes and column electrodes to form a pressure sensing array with a discretized structure.

[0015] Beneficial effects: Compared with the continuous laying of the upper electrode film in the traditional structure, even if only local pressure is applied, the entire film will be stretched, causing adjacent pixels to deform and resulting in mechanical crosstalk; in this application, each sensing unit is independent and the sensing units are separated by physical gaps, without contact or linkage, clearly distinguishing adjacent pressure points. The pressure will only act on the sensing unit and will not spread to the surrounding area. Therefore, mechanical stress cannot be transmitted across units, and local pressure will no longer cause surrounding pixels to respond, thus avoiding mechanical crosstalk. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall structure of the pressure sensing array based on the discretized structure in this application; Figure 2 This is a schematic diagram of the distribution of the conductive layer on the lower substrate in this application; Figure 3 This is a schematic diagram of the structure of the discretized sensing layer in this application; Figure 4 This is a top view of the deformed sensor array; Figure 4 (a) shows a top view of the deformed sensor array in the control group 1 with a normal structure; Figure 4 (b) shows a top view of the deformed sensor array with row and column structure in control group 2; Figure 4 (c) represents a top view of the deformed sensor array in the mechanical isolation structure of control group 3; Figure 4 (d) represents a top view of the deformed sensor array of the discrete structure in this application; Figure 5 It is a cross-sectional view of the deformed sensor array; Figure 5 (e) represents the deformed cross-sectional view of the sensor array in the ordinary structure of control group 1; Figure 5 (f) represents the deformed cross-sectional view of the sensor array in the row and column structure of control group 2; Figure 5 (g) represents the cross-sectional view of the deformed sensor array in the mechanical isolation structure of control group 3; Figure 5 (h) represents a cross-sectional view of the deformed sensor array of the discrete structure in this application; Figure 6 It is a curve of sensor array deformation; Figure 7 This is a flowchart of the fabrication method of the pressure sensing array based on the discrete structure in this application. Detailed Implementation

[0017] To make the objectives, technical solutions, and effects of this application clearer and more explicit, the following detailed description of this application is provided with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only for explaining this application and are not intended to limit this application.

[0018] Those skilled in the art will understand that, unless specifically stated otherwise, the singular forms “a,” “an,” “the,” and “the” used herein may also include the plural forms. It should be further understood that the term “comprising” as used in this application means the presence of the stated features, integers, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. It should be understood that when we say an element is “connected” or “coupled” to another element, it can be directly connected or coupled to the other element, or there may be intermediate elements. Furthermore, “connected” or “coupled” as used herein can include wireless connections or wireless coupling. The term “and / or” as used herein includes all or any units and all combinations of one or more associated listed items.

[0019] It will be understood by those skilled in the art that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. It should also be understood that terms such as those defined in general dictionaries should be understood to have the same meaning as in the context of the prior art, and should not be interpreted in an idealized or overly formal sense unless specifically defined as herein.

[0020] This application provides a pressure sensing array based on a discretized structure, such as Figure 1 As shown, the pressure sensing array based on the discretized structure includes: a lower substrate 1, a conductive layer 2, and a discretized sensing layer 3; the conductive layer 2 is disposed on the lower substrate 1; the discretized sensing layer 3 includes multiple independent sensing units 31, which are disposed on the conductive layer 2 and arranged in an array; there is a gap between each pair of adjacent sensing units 31.

[0021] Specifically, the lower substrate 1 is a mechanical support structure layer used to support the conductive layer 2 and the discretized sensing layer 3; the lower substrate 1 is located at the bottom layer. The conductive layer 2 is attached to the lower substrate 1, and the conductive layer 2 is attached to the upper surface of the lower substrate 1; the conductive layer 2 is used to construct the addressing matrix for reading the signal of each sensing unit 31, thereby providing a common electrode surface for the discretized sensing layer 3, so that the discretized sensing layer 3 can form a path with the conductive layer 2 when under pressure.

[0022] Discretized sensing layer 3 includes M There are N independent sensing units 31 (M and N are both integers greater than or equal to 1), and there is a physical gap between each pair of adjacent sensing units 31. Each sensing unit 31 is arranged on the upper surface of the conductive layer 2 (i.e. the side of the conductive layer 2 away from the lower substrate 1), so that each sensing unit 31 can generate repeatable deformation when subjected to pressure, thereby causing changes in signals such as resistance or capacitance.

[0023] Compared to traditional structures where the upper electrode film is continuously laid out, even local pressure can cause the entire film to tense, leading to deformation of adjacent pixels and signal crosstalk. In this application, each sensing unit 31 is independent, separated by physical gaps, without contact or linkage, clearly distinguishing adjacent pressure points. Pressure only acts on the sensing unit 31 and does not diffuse to the surrounding areas. Therefore, mechanical stress cannot be transmitted across units, and local pressure no longer causes corresponding responses in surrounding pixels, thus avoiding mechanical crosstalk. The discretized structure in this application enhances the adaptability of the pressure sensing array to complex pressure distributions and improves the overall spatial resolution, making it promising for applications in high-resolution pressure measurement.

[0024] One embodiment of this application, such as Figure 1 and Figure 2 As shown, the conductive layer 2 includes multiple row electrodes 21 and multiple column electrodes 22; the multiple column electrodes 22 and the multiple row electrodes 21 are arranged perpendicularly to each other to form an addressing matrix with multiple addressing units; the sensing unit 31 corresponds one-to-one with the addressing unit.

[0025] Specifically, row electrodes 21 extend along a predetermined row direction, and multiple row electrodes 21 are disposed on the upper surface of the lower substrate 1, and the multiple row electrodes 21 are parallel to each other along the row direction; the row electrodes 21 are used as signal input or output channels for each row. Column electrodes 22 extend along a predetermined column direction, and multiple column electrodes 22 are located on the same plane and above the row electrodes 21; the multiple column electrodes 22 are parallel to each other along the column direction, and the column electrodes 22 are used as signal input or output channels for each column.

[0026] Multiple row electrodes 21 and multiple column electrodes 22 are arranged perpendicularly to form an addressing matrix. The addressing matrix has multiple addressing units, each of which is surrounded by two adjacent row electrodes 21 and two column electrodes 22, thus forming a region defined by four boundary electrodes.

[0027] Each addressing unit is connected to an independent sensing unit 31, allowing each sensing unit 31 to be read independently through the combination of row and column signals. This supports independent operation of units in large arrays and enables pixel-level independent addressing. Furthermore, since each sensing unit 31 is only connected to its corresponding row and column intersection, adjacent unit circuits are isolated from each other, preventing serial numbers from flowing laterally through continuous conductive paths.

[0028] As can be seen, the upper layer of the overall structure in this application (i.e., the upper surface of the discretized sensing layer 3) does not contain any electrodes and is completely insulated. The discretized sensing layer 3 is located above the electrodes, but there is no continuous conductive material inside it. There is no direct conductor connection between the electrical signal of a single pixel and the adjacent pixels, and there is no coupling through the thin film. Signal acquisition is only at the intersection of the bottom row electrode 21 and the column electrode 22, so that each sensing unit 31 corresponds to only one independent circuit node. There is no conductive path between adjacent pixels. Therefore, when a sensing unit 31 is pressed, the electrical signal will not cross over to the adjacent pixels, avoiding electrical crosstalk and misreading.

[0029] In one embodiment of this application, the conductive layer 2 further includes a plurality of bent electrodes 24; the bent electrodes 24 are disposed within the addressing unit and are respectively connected to the row electrode 21 and column electrode 22 corresponding to the addressing unit; the sensing unit 31 is disposed on the bent electrodes 24.

[0030] Specifically, there are multiple curved electrodes 24, and there is a one-to-one correspondence between the curved electrodes 24, the addressing units, and the sensing units 31. The row electrodes 21 are used for row signal input or output, and the column electrodes 22 are used for column signal input or output. The row electrodes 21 and column electrodes 22 are arranged vertically and crosswise to form the basic framework of the pixel addressing matrix, while the row electrodes 21 and column electrodes 22 form the logical boundary of each addressing unit.

[0031] The bent electrode 24 is located within the addressing unit, and part of the bent electrode 24 is connected to the corresponding row electrode 21 and part is connected to the corresponding column electrode 22. The two parts are not in direct contact. Thus, the bent electrode 24 electrically connects the independent sensing unit 31 within the addressing unit to the underlying row and column electrodes 22, providing a flexible layout position for the sensing unit 31 and ensuring the independence of each sensing unit 31.

[0032] In this application, the conductive layer 2 further includes an insulating portion 23; the insulating portion 23 is disposed between the row electrode 21 and the column electrode 22, and is located at the intersection between the row electrode 21 and the column electrode 22.

[0033] Specifically, there are multiple insulating portions 23. Insulating portions 23 are provided at the vertical intersections between row electrodes 21 and column electrodes 22, and are located in the middle layer of the conductive layer 2, i.e., between row electrodes 21 and column electrodes 22. Both row electrodes 21 and column electrodes 22 are used for conduction. If they directly contact each other at the intersection, a short circuit will be formed, causing the row and column signals of the entire matrix electrodes to mix together, making it impossible to address each sensing unit 31 individually. In this application, insulating portions 23 are provided at the intersections between row electrodes 21 and column electrodes 22. These insulating portions 23 separate the two conductors at the intersections, preventing any row or column from directly short-circuiting.

[0034] The width of the row electrode 21 is smaller than the width of the insulating portion 23 along the column direction, and the width of the column electrode 22 is smaller than the width of the insulating portion 23 along the row direction, so that the insulating portion 23 can completely block the intersection between the row electrode 21 and the column electrode 22, effectively preventing direct short circuit between the row and column.

[0035] In one embodiment of this application, both the row electrode 21 and the column electrode 22 are attached to the lower substrate 1.

[0036] Specifically, during array scanning, row electrodes 21 are typically activated row by row, and signals are read row by row. By attaching row electrodes 21 to the lower substrate 1, continuity and low resistance of the row electrodes 21 can be achieved. Row signals can be directly transmitted to the corresponding matrix without bypassing other electrodes or obstacles, thus providing a low-resistance continuous path for each addressing unit and sensing unit 31. Column electrodes 22 are also attached to the lower substrate 1 and connected to sensing units 31 via bent electrodes 24, resulting in short signal paths and allowing sensing units 31 to operate independently, facilitating layout and manufacturing.

[0037] It should be noted that the number (M, N) and structural parameters of the sensing units 31 in the discretized sensing layer 3 need to be determined according to actual requirements; the smaller the structural parameters of the sensing unit 31, the higher the resolution of the pressure sensing array. At the same time, during the design and manufacturing process, it is necessary to ensure that the discretized sensing layer 3 is precisely aligned with the lower substrate 1 and remains stable, ensuring that each sensing unit 31 works independently and avoiding interference between adjacent units, thereby achieving a high-resolution, low-crosstalk pressure sensing array.

[0038] One embodiment of this application, such as Figure 3 As shown, the sensing unit 31 includes a sensing microstructure 311 and a microstructure support frame 312; the microstructure support frame 312 is disposed outside the sensing microstructure 311 and wraps around the sensing microstructure 311.

[0039] Specifically, the sensing microstructure 311 is located inside the sensing unit 31 and is the sensitive part that actually senses pressure. It is used to deform under external pressure and generate electrical signals that indicate changes in resistance, capacitance, or conductivity. The microstructure support frame 312 is located on the outer layer of the sensing microstructure 311 and wraps around it. It provides mechanical support, fixes the sensing microstructure 311 inside the sensing unit 31, controls the compression and deformation range of the sensing microstructure 311, and ensures the stable operation of the sensing unit 31.

[0040] Furthermore, the microstructure support frame 312's containment and support of the sensing microstructure 311 ensures that the sensing microstructure 311 has a fixed position within the microstructure support frame 312, allowing each sensing unit 31 to respond to pressure independently, avoiding interference from adjacent units, and making the pressure sensing response controllable. The sensing microstructure 311 can have various shapes, and the microstructure support frame 312, located outside the sensing microstructure 311, ensures that the sensing microstructure 311 effectively transmits signals without collapsing.

[0041] Therefore, in this application, the sensing unit 31 is wrapped within the microstructure support frame 312, so that each sensing unit 31 can accurately sense pressure changes while maintaining structural stability when subjected to pressure, thus ensuring the independence of the sensing unit 31. This achieves a high-resolution, low-crosstalk discrete pressure sensing array, which is also convenient for array arrangement and mass production.

[0042] It is understood that the bottom surface of the sensing microstructure 311 needs to be at least partially exposed relative to the microstructure support frame 312, so as to ensure that after the sensing unit is mounted on the conductive layer 2, the sensing microstructure 311 can achieve electrical connection with the conductive layer 2. In this application, multiple sensing units 31 have multiple sensing microstructures 311, and all sensing microstructures 311 can adopt the same structure, or they can adopt different structures, or they can adopt a partial number of the same structure and a partial number of different structures.

[0043] When all sensing microstructures 311 adopt the same structure, the pressure sensing array of this application can ensure that the electrical characteristics of each sensing unit 31 are similar, the calibration is simple, it is easy to realize a large-area array, the spatial resolution is high, and it is suitable for uniform pressure distribution measurement scenarios such as planar contact pressure and glove tactile sensing.

[0044] For scenarios involving complex pressure distributions or heterogeneous surfaces such as curved human body surfaces, multi-morphic tactile feedback in robots, and flexible electronic skin, it is suitable for multiple sensing units 31 in the pressure sensing array to adopt different sensing microstructures 311; different sensing microstructures 311 are sensitive to different pressure ranges or directions, which is more conducive to improving overall adaptability.

[0045] In one embodiment of this application, the sensing microstructure 311 is a pyramid-shaped, hemispherical, conical, wave-shaped, or micro-dome-shaped steady-state microstructure. Its shape remains basically stable within the normal pressure range and will not collapse or permanently deform, so that the sensing microstructure 311 produces controllable deformation when external force is applied, and the signal is stable and highly repeatable.

[0046] The pyramid-shaped sensing microstructure 311 features concentrated pressure at its apex, resulting in high sensitivity and suitability for pressure sensing in small areas. The hemispherical sensing microstructure 311 exhibits a smooth pressure distribution, making it suitable for sensing pressure on planar or curved surfaces. The conical sensing microstructure 311 offers controllable height, predictable deformation, and good linear response. The wave-shaped sensing microstructure 311 boasts high surface flexibility, adapting to irregularly shaped surfaces. The micro-dome-shaped sensing microstructure 311 exhibits good elasticity, high resilience, and is less prone to fatigue during long-term use.

[0047] In another embodiment of this application, the sensing microstructure 311 is a non-steady-state microstructure such as a high aspect ratio cylinder or a gradient fillable structure. It can undergo significant deformation within the working pressure range, and its electrical parameters respond rapidly to pressure changes. It is sensitive to pressure changes and can achieve a large dynamic range measurement, which significantly improves the sensitivity, dynamic range and ability to adapt to complex pressure distribution of the pressure sensing array, thereby enhancing the overall performance of the pressure sensing array.

[0048] The high aspect ratio cylindrical sensing microstructure 311 has a large vertical height and a small cross-section, resulting in high sensitivity under low pressure and compressibility under high pressure, making it suitable for a wide dynamic range. The gradient-fillable structure can be filled internally, and the pressure response can be staged linearly, making it suitable for complex or multi-level pressure sensing scenarios.

[0049] In one embodiment of this application, the material of the lower substrate 1 is one or more of PDMS (polydimethylsiloxane), SEBS (styrene-ethylene-butene-styrene block copolymer), ECOFLEX (eco-elastomer), polyurethane, and polyimide, which can take into account flexibility, elasticity, mechanical support, and durability. This not only ensures that the pressure sensing array works stably in deformable or bending environments, but also facilitates manufacturing and application to curved surfaces, making it suitable for wearable robots and high-temperature industrial scenarios.

[0050] The materials of row electrodes 21 and column electrodes 22 are selected from composite conductive materials formulated with carbon nanoparticles, gold nanoparticles, platinum nanoparticles, silver nanoparticles, and copper nanoparticles, or one or more conductive materials such as carbon nanoparticles, gold nanoparticles, platinum nanoparticles, silver nanoparticles, and copper nanoparticles. They not only have high conductivity and good flexible processing properties, but also maintain stable performance under bending and repeated use conditions. At the same time, the material ratio can be adjusted according to needs to optimize electrical performance.

[0051] The insulating part 23 can be made of one or more non-conductive materials such as epoxy resin, photosensitive resin, polydimethylsiloxane (PDMS), SEBS (styrene-ethylene-butene-styrene block copolymer), and ECOFLEX, which can effectively isolate the row electrode 21 and the column electrode 22 to prevent short circuits or signal interference. At the same time, these materials have flexibility, processability and good mechanical stability, which can adapt to the deformation requirements of the microstructure sensing unit 31 and ensure that the array works stably under bending, stretching or complex pressure environments, thereby improving the reliability and durability of the pressure sensing array.

[0052] The material of the microstructure support frame 312 can be selected from one or more of the following: epoxy resin, photosensitive resin, copper, steel, alloy, polydimethylsiloxane (PDMS), SEBS (styrene-ethylene-butene-styrene block copolymer), ECOFLEX, etc., and the rigidity and flexibility can be considered according to the requirements. Metal or alloy provides high strength and stable support, ensuring that the sensing microstructure 311 is not easily deformed under high pressure or repeated loads; materials such as epoxy resin, photosensitive resin, PDMS, SEBS and ECOFLEX have good elasticity and flexibility, which can adapt to the deformation of the sensing microstructure 311 and protect the sensing unit 31, improve the durability and reliability of the array, and facilitate processing and discrete arrangement.

[0053] The material of the sensing microstructure 311 can be one or more of copper, silver, iron, graphite, steel, alloy or formulated composite conductive materials. These materials have good conductivity and mechanical strength, and can transmit electrical signals quickly and stably under external pressure, while ensuring the controllable deformation and durability of the microstructure, thereby improving the sensitivity, response speed and overall array reliability of the pressure sensing unit 31.

[0054] This application uses COMSOL multiphysics simulation software to perform three-dimensional modeling and simulation of a pressure sensing array based on a discretized structure. In the model, the thickness of the lower substrate 1 is 0.05 mm, the discretized sensing layer 3 is a 5×5 addressing matrix, the size of each sensing unit 31 is 0.5×0.5 mm, and the interval between two adjacent sensing units 31 is 0.25 mm. To verify the effect of the discretized structure in reducing crosstalk, three control models were established: control group 1 is a normal structure, in which the upper and lower substrates 1 have the same structure, both being continuous structures without discretization; control group 2 is a row-column structure, in which a support structure is added between the upper and lower substrates 1 to isolate sensing units 31 in different rows or columns; control group 3 is a mechanical isolation structure, in which a support structure is added between the upper and lower substrates 1 of the normal structure model to isolate adjacent units.

[0055] All models use free tetrahedral ultrafine meshes. When selecting the cell size, it is predefined as ultrafine. The lower surface and four sides of the sensor array model are set as fixed constraint surfaces. On the upper surface of the discrete substrate of the middle cell of the sensor array model, a fixed displacement of 0.08 mm is added. The signal crosstalk is reflected by the deformation displacement of the adjacent sensor cells 31.

[0056] from Figure 4 , Figure 5 and Figure 6 It can be seen that the deformation response of different structures varies significantly. For example... Figure 4 and Figure 5 ( Figure 5 As shown in the diagram (where x represents the horizontal direction and y represents the vertical direction), compared to control groups 1, 2, and 3, the discretized sensing unit 31 in this application exhibits a significantly reduced deformation range under external pressure, minimizing its impact on the surrounding area. For example... Figure 6 As shown, the displacement of the central element in all four structures is 80 μm, but the displacement difference between the left and right ends of adjacent second elements is as follows: Control group 1 – 57.99 μm, Control group 2 – 12.88 μm, Control group 3 – 4.52 μm, and this application – 1.45 μm. This demonstrates that the discretized structure of this application is most effective in suppressing mechanical transmission between elements, with the response of adjacent elements reduced to an extremely low level and signal crosstalk significantly decreased. Compared to the three control structures, the discretized design of this application can more effectively block the propagation of stress between elements, enabling the sensing array to more accurately reflect local pressure changes, thereby significantly improving the overall spatial resolution.

[0057] Therefore, in this application, the conductive layer 2 is disposed on the lower substrate 1, and the discretization of the sensing unit 31 can overcome the problem of signal crosstalk that easily occurs in adjacent areas in traditional continuous microstructure pressure arrays. This is especially advantageous under high pressure or complex pressure distribution conditions, providing a more reliable structural design basis for high-resolution pressure measurement scenarios and having broad application prospects.

[0058] Based on any of the discretized pressure sensing arrays described above, this application also provides a method for fabricating a discretized pressure sensing array, such as... Figure 7 As shown, the preparation method includes the following steps: S100. On the upper surface of the lower substrate, multiple row electrodes, insulating portions covering the row electrodes, and multiple column electrodes covering the insulating portions are sequentially formed layer by layer using a mask pattern deposition process to construct a substrate with an addressing matrix. Specifically, a substrate 1 and three photomasks are provided. After cleaning and drying the substrate 1, the first photomask (the hollow pattern on the first photomask corresponds to the pattern of multiple row electrodes 21 arranged in a regular manner) is first covered on the upper surface of the substrate 1 and fixed to ensure that there is no relative movement between the first photomask and the substrate 1. Then, an adhesion layer is deposited on the substrate 1 by magnetron sputtering silver metal particles according to the target film thickness to form multiple row electrodes 21 arranged in a regular manner.

[0059] Next, a second photomask (with a cutout pattern on the second photomask corresponding to the pattern of multiple regularly arranged insulating portions 23) is placed on the row electrode 21. One or more non-conductive materials, such as epoxy resin, photosensitive resin, polydimethylsiloxane (PDMS), SEBS (styrene-ethylene-butene-styrene block copolymer), and ECOFLEX, are sprayed or dotted onto the second photomask to form insulating portions 23 on the row electrode 21.

[0060] Then, a third mask (the cutout pattern on the third mask corresponds to the pattern of multiple regularly arranged column electrodes 22) is placed on the upper surface of the insulating part 23 and precisely aligned and fixed to ensure that the pattern of column electrodes 22 can be arranged perpendicularly to the row electrodes 21, and that there is no relative movement between the third mask and the lower substrate 1; then, an adhesion layer is deposited by magnetron sputtering silver metal particles according to the target film thickness to form multiple regularly arranged row electrodes 21.

[0061] S200: The conductive ink is molded into an integral sensing microstructure sheet, and then cured and demolded. Specifically, a microstructure mold is pre-designed based on the shape and structure of the sensing microstructure 311. Pre-mixed conductive ink is poured into the mold cavity, and the conductive ink is then used to fully fill each microstructure area within the mold through methods such as scraping and pressing, forming a continuous sheet with a predetermined morphology. To avoid air bubbles forming within the mold, slight vibration or vacuum degassing can be used during the ink application process to ensure uniform distribution of the conductive ink. After the conductive ink is filled, it undergoes a curing treatment (such as thermosetting, photocuring, or photothermal composite curing) before demolding.

[0062] S300: Divide the sensing microstructure sheet to obtain multiple independent sensing microstructures; Specifically, the overall sensing microstructure sheet is cut using methods such as die-cutting or laser cutting to form multiple electrically independent, mechanically complete, and dimensionally qualified sensing microstructures 311.

[0063] S400: Cast an elastomer material on the surface of the sensing microstructure and cure it to obtain multiple independent sensing units. Specifically, multiple independent sensing microstructures 311 obtained by cutting and separating are arranged in an array. An elastomer material (such as epoxy resin, photosensitive resin, copper, steel, alloy, polydimethylsiloxane (PDMS), SEBS (styrene-ethylene-butene-styrene block copolymer), ECOFLEX, etc.) is cast and covered on all sensing microstructures 311, so that the outer surface of each sensing microstructure 311 that is not electrically connected to the conductive layer 2 is covered with the elastomer material. After casting, it is cured to form a continuous support frame, that is, to form a connected elastomer bridge between the sensing microstructures 311.

[0064] The continuous support frame is cut according to the size of the sensing unit 31 to form multiple independent sensing units 31, wherein the sensing unit 31 includes a microstructure support frame 312 and a sensing microstructure 311 located within the microstructure support frame 312.

[0065] S500: The sensing unit is attached one-to-one with the addressing unit of the addressing matrix on the substrate, and the sensing unit is connected to the corresponding row electrode and column electrode to form a pressure sensing array with a discretized structure.

[0066] Specifically, multiple mechanically independent sensing units, which have been fabricated previously, are arranged on the lower substrate according to a pre-designed grid order. Each sensing unit corresponds to an addressing unit on the lower substrate. After precise alignment of the sensing units and addressing units, the sensing units are connected to the curved electrodes within the addressing units, achieving electrical connection between the sensing units and the row and column electrodes, thus forming a pressure sensing array with a discrete structure.

[0067] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0068] Furthermore, 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 indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0069] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0070] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "beneath" of the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0071] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0072] Of course, the above description of the embodiments of the present invention is quite detailed, but it should not be construed as a limitation on the scope of protection of the present invention. The present invention may have many other implementations. Based on this implementation, other implementations obtained by those skilled in the art without any creative effort are all within the scope of protection of the present invention. The scope of protection of the present invention is determined by the appended claims.

Claims

1. A pressure sensing array based on a discrete structure, characterized in that, It includes: Lower base; A conductive layer is disposed on the lower substrate; The discrete sensing layer includes multiple independent sensing units, which are disposed on the conductive layer and arranged in an array; there is a gap between each pair of adjacent sensing units.

2. The pressure sensing array based on a discretized structure according to claim 1, characterized in that, The conductive layer includes: Multiple row electrodes; Multiple column electrodes; multiple column electrodes and multiple row electrodes are arranged perpendicularly to each other to form an addressing matrix with multiple addressing units; the sensing unit corresponds one-to-one with the addressing unit.

3. The pressure sensing array based on a discrete structure according to claim 2, characterized in that, The conductive layer further includes: A curved electrode is disposed within the addressing unit and is connected to the row electrode and column electrode corresponding to the addressing unit, respectively; the sensing unit is disposed on the curved electrode.

4. The pressure sensing array based on a discrete structure according to claim 2, characterized in that, The conductive layer further includes: An insulating portion is disposed between the row electrode and the column electrode, and located at the intersection between the row electrode and the column electrode.

5. The pressure sensing array based on a discrete structure according to claim 2, characterized in that, Both the row electrode and the column electrode are attached to the lower substrate.

6. The pressure sensing array based on a discrete structure according to claim 1, characterized in that, The sensing unit includes: Sensing microstructures for electrical connection to the conductive layer; A microstructure support frame is disposed outside the sensing microstructure and encloses the sensing microstructure.

7. The pressure sensing array based on a discrete structure according to claim 6, characterized in that, The sensing microstructure is a pyramid-shaped, hemispherical, conical, wave-shaped, or micro-dome-shaped microstructure.

8. The pressure sensing array based on a discretized structure according to claim 1, characterized in that, The material of the lower substrate is one or more of PDMS, SEBS, ECOFLEX, polyurethane, and polyimide.

9. A method for fabricating a pressure sensing array based on a discrete structure as described in any one of claims 4-8, characterized in that, It includes the following steps: On the upper surface of the lower substrate, multiple row electrodes, insulating portions covering the row electrodes, and multiple column electrodes covering the insulating portions are sequentially formed layer by layer using a mask pattern deposition process to construct a substrate with an addressing matrix. Conductive ink is molded into a single sensing microstructure sheet, and then cured and demolded. The sensing microstructure sheet is segmented to obtain multiple independent sensing microstructures; An elastomer material is cast onto the surface of the sensing microstructure and then cured to obtain multiple independent sensing units. The sensing units are attached one-to-one with the addressing units of the addressing matrix on the substrate, and the sensing units are connected to the corresponding row electrodes and column electrodes to form a pressure sensing array with a discretized structure.

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