Temperature and humidity compensation flexible piezoresistive sensor and pressure sensing system

Abstract

The invention discloses a flexible piezoresistive sensor with temperature and humidity compensation and a pressure sensing system, and belongs to the technical field of flexible sensors, the flexible piezoresistive sensor comprises a first base layer, a second base layer and a sensing circuit arranged between the first base layer and the second base layer; the sensing circuit comprises a pressure sensing part and a compensation part, and the pressure sensing part and the compensation part are arranged in a coplanar manner; wherein the pressure sensing part comprises a pressing layer and a first circuit layer, and the pressure sensing part is an open circuit when not pressed; the compensation part comprises a compensation layer and a second circuit layer, and the compensation part is a path in the sensing circuit. According to the flexible piezoresistive sensor for temperature and humidity compensation, the resistance value of the pressure sensing part can be compensated through the compensation part, so that the resistance value of the pressure sensing part in a temperature and humidity environment is compensated, and the accuracy of pressure sensing is ensured; and secondly, the compensation part enables the sensing circuit to be always in a conducting state, whether the sensor works effectively or not can be judged, pressure sensing misjudgment caused by sensor damage is avoided, and the monitoring accuracy of the sensor is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of flexible sensors, and particularly relates to a flexible piezoresistive sensor with temperature and humidity compensation and a pressure sensing system. Background Art

[0002] Flexible pressure sensors have great advantages in electronic skin, health monitoring, human-computer interaction, and implantable diagnosis. Currently, pressure sensors are mainly divided into capacitive, piezoresistive, piezoelectric, etc. according to the form of energy and information conversion. Among them, piezoresistive pressure sensors have the advantages of simple structure, high sensitivity, and stable performance, and have broad application prospects.

[0003] Currently, the mainstream piezoresistive pressure sensors are mainly based on the change characteristics of the interface contact resistance. By regulating the size, quantity of surface micro-protrusions at the contact interface and optimizing the contact points, etc., the total contact area is made as large as possible to obtain more accurate resistance perception. However, the flexible pressure sensor is entirely prepared with flexible materials, and space needs to be reserved at the circuit and pressure sensing regions for pressure sensing transmission. During long-term use, due to the influence of external temperature, humidity, etc., the performance of the piezoresistive material itself is likely to change, resulting in problems such as signal drift and inconsistency in the output signal of the sensor, leading to the inability of the pressure sensor to obtain accurate pressure data and affecting the normal use of the pressure sensor. Summary of the Invention

[0004] In view of one or more of the above defects or improvement requirements in the prior art, the present invention provides a flexible piezoresistive sensor with temperature and humidity compensation to solve the problem of deviation in pressure data testing of existing pressure sensors under the influence of temperature, humidity, etc.

[0005] To achieve the above object, the present invention provides a flexible piezoresistive sensor with temperature and humidity compensation, which includes a first base layer and a second base layer, and a sensing circuit disposed between the first base layer and the second base layer. The sensing circuit includes a pressure sensing part and a compensation part. The pressure sensing part can change its resistance according to pressure changes, the compensation part can change its resistance according to temperature and / or humidity changes, and the pressure sensing part and the compensation part are arranged coplanarly; Wherein, the pressure sensing part includes a pressing layer disposed on the second base layer and a first circuit layer disposed on the first base layer. The first circuit layer is a part of the sensing circuit, and there is a gap between the pressing layer and the first circuit layer, so that the pressure sensing part is an open circuit when not pressed; The compensation part includes a compensation layer disposed on the second base layer and a second circuit layer disposed on the first base layer. The second circuit layer is a part of the sensing circuit, and the compensation layer is in contact with the second circuit layer, so that the compensation part is a closed circuit in the sensing circuit.

[0006] As a further improvement of the present invention, a plurality of the pressure sensing parts are provided between the first base layer and the second base layer, and the plurality of pressure sensing parts are evenly distributed between the first base layer and the second base layer.

[0007] As a further improvement of the present invention, the resistance strain coefficients of the pressing part and the compensating part with respect to temperature and / or humidity are the same.

[0008] As a further improvement of the present invention, the plurality of pressure sensing parts are arranged in parallel with the compensating part.

[0009] As a further improvement of the present invention, the plurality of pressure sensing parts are connected in parallel to form a sensing end, and the sensing end is connected in series with the compensating part.

[0010] As a further improvement of the present invention, the second circuit layer includes a plurality of sensing electrodes arranged side by side at intervals, the pressing layer includes a plurality of sensing sheets arranged side by side at intervals, and each of the sensing sheets is embedded between each of the sensing electrodes.

[0011] As a further improvement of the present invention, the first circuit layer includes a plurality of sensing electrodes arranged side by side at intervals, the pressing layer is in a sheet structure, and the pressing layer at least partially covers the area of the first circuit layer in the thickness direction.

[0012] As a further improvement of the present invention, a hard gasket is further provided between the first base layer and the pressing layer, and the hard gasket has the same size as the pressing layer.

[0013] As a further improvement of the present invention, a support layer is further provided between the first base layer and the second base layer, the support layer is provided with a plurality of embedding areas, and the sensing circuit, the pressing layer and the compensating layer are respectively arranged in each of the embedding areas.

[0014] This application further includes a pressure sensor system, which includes a power supply, the power supply is electrically connected to the flexible piezoresistive sensor with temperature and humidity compensation and a display component, and the display component can correspondingly display the resistance value of the flexible piezoresistive sensor with temperature and humidity compensation.

[0015] As long as the above-mentioned improved technical features do not conflict with each other, they can be combined with each other.

[0016] Generally speaking, compared with the prior art, the beneficial effects of the above technical solutions conceived by the present invention include: (1)The flexible piezoresistive sensor with temperature and humidity compensation of the present invention realizes the resistance correction of the pressure sensing part under the influence of temperature and humidity by arranging a compensation part inside the first base layer and the second base layer and using the compensation part to sense temperature and / or humidity, so as to accurately detect pressure in a temperature and / or humidity environment, thereby improving the accuracy of pressure sensing of the sensor and expanding the applicable scenarios of the sensor. Further, in the present application, the compensation part is arranged inside the sensor, and a combination form similar to that of the pressure sensing part is adopted for the compensation layer and the circuit layer, so that the compensation part and the pressure sensing part are in an approximately equal thickness state, ensuring that the compensation part will not cause an increase in the overall thickness of the sensor or obvious bulging when installed inside the sensor, and the compensation part will not affect the normal pressure sensing of the pressure sensing part, thus ensuring the accuracy of pressure sensing of the sensor. At the same time, in the present application, the compensation layer of the compensation part is always in a crimped state with the second circuit layer, so that the circuit of the sensor is always in a conducting state. Whether the pressure sensing part can work effectively can be judged by whether the sensor has resistance, avoiding the problem that a conventional pressure sensor is in an open state when not in use, which is the same as the open circuit state when the sensor is damaged, resulting in the same state of the sensor when not under pressure or damaged, and thus affecting the user's misjudgment of the use state of the sensor and the monitoring of the sensor.

[0017] (2)The flexible piezoresistive sensor with temperature and humidity compensation of the present invention selects materials with the same resistance strain coefficient, so that the resistances of the pressing layer and the compensation layer change synchronously under the influence of temperature and humidity, thereby ensuring the stable compensation of the resistance of the pressing layer by the compensation layer and further ensuring the accuracy of pressure monitoring of the sensor in specific environments such as temperature and humidity. Description of the Drawings

[0018] Figure 1 is the overall structural schematic diagram of the flexible piezoresistive sensor with temperature and humidity compensation in an embodiment of the present invention; Figure 2 is the internal structural schematic diagram of the flexible piezoresistive sensor with temperature and humidity compensation in an embodiment of the present invention; Figure 3 is the overall structural schematic diagram of the pressure sensing part in an embodiment of the present invention; Figure 4 is the overall structural schematic diagram of the compensation part in an embodiment of the present invention; Figure 5 is the circuit structural schematic diagram of one of the flexible piezoresistive sensors with temperature and humidity compensation in an embodiment of the present invention; Figure 6 is the circuit structural schematic diagram of another flexible piezoresistive sensor with temperature and humidity compensation in an embodiment of the present invention.

[0019] In all the drawings, the same reference numerals denote the same technical features, specifically: 1. First base layer; 2. Second base layer; 3. Sensing circuit; 4. Pressing layer; 5. First circuit layer; 6. Compensation layer; 7. Second circuit layer; 8. Support layer. Detailed implementation

[0020] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0021] In the description of the present invention, it should be understood that unless otherwise specified, the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation to the present invention.

[0022] In addition, unless otherwise specified, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of the present invention, the meaning of "a plurality" is at least two, such as two, three, etc., unless otherwise specifically defined.

[0023] In the present invention, unless otherwise clearly defined and limited, the terms "mounted", "connected", "connected to", "fixed", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal connection of two components or the interaction relationship between two components, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0024] In the present invention, unless otherwise clearly specified and defined, the first feature being "on" or "under" the second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on top of" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature being "under", "beneath" and "underneath" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply indicates that the horizontal height of the first feature is less than that of the second feature.

[0025] Embodiment: Please refer to Figures 1 - 6 , the flexible piezoresistive sensor with temperature and humidity compensation in the preferred embodiment of the present invention includes a first base layer 1 and a second base layer 2, and a sensing circuit 3 disposed between the first base layer 1 and the second base layer 2. The sensing circuit 3 includes a pressure sensing part and a compensation part. The pressure sensing part can change its resistance according to the pressure change, and the compensation part can change its resistance according to the temperature and / or humidity change. And the pressure sensing part and the compensation part are disposed coplanarly. The pressure sensing part includes a pressing layer 4 disposed on the second base layer 2 and a first circuit layer 5 disposed on the first base layer 1. The first circuit layer 5 is a part of the sensing circuit 3, and there is a gap between the pressing layer 4 and the first circuit layer 5 so that the pressure sensing part is open circuit when not pressed; at the same time, the compensation part includes a compensation layer 6 disposed on the second base layer 2 and a second circuit layer 7 disposed on the first base layer 1. The second circuit layer 7 is also a part of the sensing circuit 3, and the compensation layer 6 is in contact with the second circuit layer 7 so that the compensation part is a closed circuit in the sensing circuit 3.

[0026] Specifically, the flexible piezoresistive sensor with temperature and humidity compensation in the present application realizes the compensation of the resistance value of the pressure sensing part by arranging a compensation part inside the first base layer 1 and the second base layer 2 and using the compensation part to sense the temperature and / or humidity, so as to correct the resistance value of the pressure sensing part under the influence of temperature and humidity, realize the accurate detection of pressure by the sensor in a temperature and / or humidity environment, and further improve the accuracy of pressure sensing of the sensor and the applicable scenarios of the sensor. Further, the present application arranges the compensation part inside the sensor and adopts a combination form of a compensation layer 6 and a circuit layer similar to that of the pressure sensing part, so that the compensation part and the pressure sensing part are in an approximately equal thickness state, ensuring that when the compensation part is placed inside the sensor, it will not cause the overall thickness of the sensor to increase or obvious bulging, etc., and the compensation part will not affect the normal pressure sensing of the pressure sensing part, ensuring the accuracy of pressure sensing of the sensor.

[0027] Meanwhile, the compensation layer 6 of the compensation part in the present application and the second circuit layer 7 are always in a crimped state, so that the circuit of the sensor is always in a conducting state. Whether the pressure sensing part can work effectively can be judged by whether the sensor has resistance value, avoiding the conventional pressure sensor being in an open state when not in use, which is the same as the open state when the sensor is damaged, resulting in the same state of the sensor when not pressed or damaged, thus affecting the user's misjudgment of the use state of the sensor and the monitoring of the sensor. Further, in the actual use scenario, when the flexible piezoresistive sensor with temperature and humidity compensation is connected and used, the external power supply can supply power to the sensor, and the compensation part of the sensor is always in a connected state. When the sensor fails or changes, the resistance value at the compensation part will change correspondingly, thereby causing the data of the external device connected to the sensor to change correspondingly, so that the user can know the state of the sensor, that is, the piezoresistive sensor in the present application can monitor the working state of the sensor during use to know the time node when the sensor is damaged or fails.

[0028] Meanwhile, the compensation layer 6 and the second circuit layer 7 in the present application are both arranged between the first base layer 1 and the second base layer 2. In the actual setting process, the compensation layer 6 or the second circuit layer 7 can be closely arranged on the first base layer 1 or the second base layer 2 to ensure that the two are integrally arranged and in a connected state.

[0029] Further preferably, the first base layer 1 and the second base layer 2 in the present application are PET (polyethylene terephthalate) films or PI (polyimide) films. PET films or PI films have excellent high and low temperature resistance, electrical insulation, adhesiveness, radiation resistance, chemical resistance, etc. Of course, in addition to the above PET films or PI films, other films with good weather resistance can also be used as the first base layer 1 and the second base layer 2.

[0030] Further, as an optional embodiment of the present invention, the resistance strain coefficients of the pressing layer 4 and the compensation layer 6 with respect to temperature and / or humidity are the same. The resistance strain coefficients of the pressing layer 4 and the compensation layer 6 with respect to temperature and / or humidity being the same means that the resistance values of the pressing layer 4 and the compensation layer 6 change proportionally with the changes in temperature and / or humidity, that is, the change rates of the pressing layer 4 and the compensation layer 6 at different temperatures and / or humidities are the same. By selecting materials with the same resistance strain coefficients, the resistances of the pressing layer 4 and the compensation layer 6 change synchronously under the influence of temperature and humidity, so as to ensure the stable compensation of the resistance of the compensation layer 6 to the pressing layer 4, and further ensure the accuracy of pressure monitoring of the sensor in specific environments such as temperature and humidity.

[0031] Further, as an alternative embodiment of the present invention, a plurality of pressure sensing portions are provided between the first base layer 1 and the second base layer 2 in the present application, and the plurality of pressure sensing portions are evenly distributed between the first base layer 1 and the second base layer 2. The plurality of pressure sensing portions can form a plurality of sensing points on the sensor, so as to test the pressures from different positions, thereby realizing the pressure monitoring at various places within the use area of the sensor. Optionally, the pressure sensing portions may also be unevenly distributed within the use range of the sensor. For example, according to actual use requirements, the pressure sensing portions are densely concentrated in some areas, or a small number of pressure sensing portions are distributed in these areas.

[0032] Further, as an alternative embodiment of the present invention, the sensing circuit 3 in the present application can be formed by means such as printing, chemical etching, lithography or dispensing, as long as a conductive circuit structure can be formed between the first base layer 1 and the second base layer 2, and the resistance of the pressure sensing portion and the compensation portion can be monitored. Specifically, when an external force acts on the sensor in the present application, the pressing layer 4 approaches the first circuit layer 5. When the two come into contact, the second circuit layer 7 is in a conducting state in the sensing circuit 3, and the resistance value at the second circuit layer 7 changes correspondingly and is reflected in the form of an electrical signal, and the electrical signal changes correspondingly with the increase of the pressure, realizing the induction of the pressure.

[0033] Optionally, the sensing circuit 3 in the present application is encapsulated between the first base layer 1 and the second base layer 2 through double-sided tape or other colloidal structures, and the circuit is exposed at the pressure sensing portion and the compensation portion. Through the form of double-sided tape pasting or glue encapsulation, it can be avoided that the rest of the sensing circuit 3 is in a good protection state except for the pressure sensing and temperature and humidity sensing parts, thereby increasing the service life of the flexible piezoresistive sensor.

[0034] Further, as an alternative embodiment of the present invention, as Figure 5 shown, the plurality of pressure sensing portions and the compensation portions in the present application are arranged in parallel. Specifically, both ends of the pressure sensing portion and the compensation portion in the present application are connected to the circuit. During the compression process, the actual resistance value of the pressure sensing portion is R 11 , and its resistance value at temperature or humidity is R 12 ; the actual resistance value of the compensation portion is R 21 , and its resistance value at temperature or humidity is R 22 . Since the resistance strain coefficients of the pressing layer 4 and the compensation layer 6 to temperature and / or humidity are the same, the compensation coefficient k of the compensation portion at the corresponding temperature or humidity is k = R 22 / R 21 . Similarly, the compensation coefficient of the pressure sensing portion at the corresponding temperature is also k, then the actual resistance value R 11 of the pressure sensing portion = R 12 / k. In this way, the actual resistance value of the pressure sensing part can be obtained. The pressure received by the pressure sensing part is linearly related to the resistance value of the pressure sensing part, and the actual pressure of the pressure sensing part can be correspondingly obtained.

[0035] Specifically, since the compensation part in this application is always connected to the circuit, when the initial resistance value of the compensation part is known, the current I of the compensation part under the open circuit of the pressure sensing part can be obtained 11 =Vcc / R 21 , when in the corresponding temperature or humidity environment, the current I flowing through the compensation part 12 =Vcc / R 22 =Vcc / (R 21 *k). In this way, the compensation coefficient k under the current temperature and humidity can be obtained; when the pressure sensing part is under pressure, the circuit of the pressure sensing part is in an actual connected state. At this time, the measured resistance value R of the pressure sensing part 12 The actual resistance value R can be obtained through conversion by the compensation coefficient 11 , and the actual pressure corresponding to the pressure sensing part is obtained in this way.

[0036] Furthermore, as an optional embodiment of the present invention, as Figure 6 shown, multiple pressure sensing parts in this application are connected in parallel to form a sensing end, and the sensing end and the compensation part are connected in series. Specifically, both ends of the pressure sensing part and the compensation part in this application are connected to the circuit, and the compensation coefficient of the pressure sensing part and the compensation part under temperature and / or humidity is also k. When the sensing end and the compensation part are connected in series, when the pressure sensing end of the sensing circuit 3 is under pressure, its output voltage under standard conditions is Vcc*R 11 / (R 11 +R 21 ); when this flexible piezoresistive sensor is affected by temperature and / or humidity, its output voltage under the same pressure is Vcc*R 12 / (R 12 +R 22 )=Vcc*R 11 *k / (R 11 *k+R 12 *k)=Vcc*R 11 / (R 11 +R 12 ). It can be seen that when the sensing end and the compensation part in this application are connected in series, their output voltages under standard conditions and under the influence of temperature or humidity are the same. At this time, the influence of temperature and humidity is eliminated. At this time, the output voltage of this flexible piezoresistive sensor is not affected by temperature and / or humidity, and the magnitude of the pressure received by the pressure sensing part can be accurately calculated.

[0037] Further optionally, the flexible piezoresistive sensor with temperature and humidity compensation in the present application mainly obtains the resistance value of the pressure sensing part through the voltage division law, and then obtains the specific pressure value of the pressure sensing part through the linear relationship between the resistance of the pressure sensing part and the pressure.

[0038] Specifically, the standard state of the flexible piezoresistive sensor here refers to the state where the sensor is not affected by temperature and / or humidity, that is, the resistance value of the pressure sensing part will not change due to the influence of temperature and / or humidity.

[0039] Further, as an alternative embodiment of the present invention, the second circuit layer 7 in the present application includes a plurality of sensing electrodes arranged side by side at intervals, and the compensation layer 6 includes a plurality of induction sheets arranged side by side at intervals. Each induction sheet is embedded between each sensing electrode. The form of mutual embedding of the induction sheet and the sensing electrode makes the overall thickness of the compensation part relatively thin, which will not affect the overall thickness of the sensor, avoids the compensation part from affecting the pressure perception of the pressure sensing part, and the mutual embedding form of the two ensures that the connection state between the compensation layer 6 and the second circuit layer 7 is basically stable, and its resistance value will not change like the pressure sensing part under the pressure state, that is, a pressure-insensitive resistance structure is formed to ensure the accurate perception of temperature and humidity by the compensation part. Secondly, the form of mutual embedding of the induction sheet and the sensing electrode can ensure that the compensation part and the sensing circuit 3 are in a conductive state, thereby indicating the working state of the sensor.

[0040] Further, as an alternative embodiment of the present invention, the first circuit layer 5 in the present application includes a plurality of sensing electrodes arranged side by side at intervals, the pressing layer 4 is a sheet-like structure, and the pressing layer 4 at least partially covers the area of the first circuit layer 5 in the thickness direction. The sheet-like structure of the pressing layer 4 is convenient for pressure sensing and can increase the contact area with the sensing electrode, thereby accurately converting the magnitude of the external pressure into the resistance value of the pressure sensing part and realizing the accurate perception of the external pressure.

[0041] Further, as an alternative embodiment of the present invention, the plurality of sensing electrodes arranged side by side at intervals at the first circuit layer 5 and the second circuit layer 7 in the present application can be interdigital electrodes.

[0042] Further, the core of the present application lies in the combined setting form of the pressure sensing part and the compensation part. The pressure sensing part has the characteristics of changing resistance under pressure and being affected by temperature and humidity; the compensation part is always in a connected state with the sensing circuit 3, and it has the characteristics of being pressure-insensitive and being affected by temperature and humidity. Among them, when the flexible piezoresistive sensor with temperature and humidity compensation is connected to an external power supply, the resistance change of the pressure sensing part at the corresponding temperature and humidity can be accurately obtained through the resistance change of the compensation part at the temperature and humidity; then this resistance change is brought into the pressure sensing part to obtain the resistance change of the pressure sensing part under the force condition, realizing the decoupling of temperature and humidity changes and pressure changes, so as to correspondingly obtain the pressure received by the flexible piezoresistive sensor with temperature and humidity compensation and realize pressure monitoring.

[0043] Further, as an alternative embodiment of the present invention, a rigid gasket is further provided between the first base layer 1 and the pressing layer 4 in the present application. The size of the rigid gasket is the same as that of the pressing layer 4. The rigid gasket is used to conduct external pressure to the pressing layer 4 to ensure the accuracy of pressure perception of the pressure sensing part. The present application is a flexible piezoresistive sensor, and its overall structure is flexible. During actual pressing, deformation problems will occur. The deformation of the pressing layer 4 will affect the contact with the first circuit layer 5, resulting in pressure sensing errors. Therefore, a rigid gasket is provided on the side of the pressing layer 4 facing away from the first circuit layer 5 to transfer external pressure to the pressing layer 4, and the rigid gasket will not deform under pressure to ensure that the pressing layer 4 attached to it maintains its shape.

[0044] Further, as an alternative embodiment of the present invention, a support layer 8 is further provided between the first base layer 1 and the second base layer 2 in the present application. A plurality of embedding areas are provided on the support layer 8, and the above-mentioned sensing circuit 3, pressing layer 4 and compensation layer 6 are all arranged in the embedding areas. The support layer 8 in the present application is mainly used to fill the non-circuit areas between the first base layer 1 and the second base layer 2, which makes the overall flexible piezoresistive sensor in a flat state, enables the sensor to be stressed evenly, and ensures the accuracy of pressure perception.

[0045] Further, the present application further includes a pressure sensing system, which includes a power supply. The power supply is electrically connected to a flexible piezoresistive sensor with temperature and humidity compensation and a display component. When the pressure sensing system operates, the power supply can supply power to the flexible piezoresistive sensor with temperature and humidity compensation and the display component, and the display component can correspondingly read and display the resistance value of the flexible piezoresistive sensor with temperature and humidity compensation, so as to facilitate the calculation of the pressure at each pressure sensing part. It should be noted that the display component in the present application can respectively read and calculate the resistance values at the compensation part and each pressure sensing part.

[0046] Those skilled in the art can easily understand that the above are only the preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A flexible piezoresistive sensor for temperature and humidity compensation, characterized in that: The invention comprises a first base layer and a second base layer, and a sensing circuit arranged between the first base layer and the second base layer, wherein the sensing circuit comprises a pressure sensing part and a compensation part, wherein the pressure sensing part can change the resistance value according to the pressure change, and the compensation part can change the resistance value according to the temperature and / or humidity change, and the pressure sensing part and the compensation part are arranged on the same plane; The pressure sensing portion includes a pressing layer disposed on the second base layer and a first circuit layer disposed on the first base layer, the first circuit layer is a part of the sensing circuit, and a gap is left between the pressing layer and the first circuit layer, so that the pressure sensing portion is open circuit when not under pressure; The compensation part includes a compensation layer arranged on the second base layer and a second circuit layer arranged on the first base layer, the second circuit layer is a part of the sensor circuit, and the compensation layer is attached to the second circuit layer, so that the compensation part is a passage in the sensor circuit.

2. The flexible piezoresistive sensor for temperature and humidity compensation according to claim 1, characterized in that: A plurality of the pressure sensing parts are provided between the first base layer and the second base layer, and the plurality of the pressure sensing parts are evenly distributed between the first base layer and the second base layer.

3. The flexible piezoresistive sensor for temperature and humidity compensation according to claim 2, characterized in that: The pressing portion and the compensating portion have the same resistance gage coefficient to temperature and / or humidity.

4. The flexible piezoresistive sensor for temperature and humidity compensation according to claim 3, characterized in that: A plurality of the pressure sensing parts are arranged in parallel with the compensation part.

5. The flexible piezoresistive sensor for temperature and humidity compensation according to claim 3, characterized in that: A plurality of the pressure sensing parts are connected in parallel to form a sensing end, and the sensing end is connected in series with the compensation part.

6. The flexible piezoresistive sensor for temperature and humidity compensation according to claim 1, characterized in that: The second circuit layer includes a plurality of sensing electrodes arranged side by side and at intervals, and the pressing layer includes a plurality of sensing sheets arranged side by side and at intervals, and each of the sensing sheets is embedded between each of the sensing electrodes.

7. The flexible piezoresistive sensor for temperature and humidity compensation according to claim 6, characterized in that: The first circuit layer includes a plurality of sensing electrodes arranged side by side and spaced apart from each other. The pressing layer is a sheet-like structure. The pressing layer at least partially covers the first circuit layer region along a thickness direction.

8. The flexible piezoresistive sensor for temperature and humidity compensation according to claim 1, characterized in that: A hard gasket is further provided between the first base layer and the pressing layer, and the hard gasket has the same size as the pressing layer.

9. The flexible piezoresistive sensor for temperature and humidity compensation according to claim 1, characterized in that: A supporting layer is further provided between the first base layer and the second base layer. A plurality of embedding areas are provided on the supporting layer. The sensing circuit, the pressing layer and the compensation layer are respectively arranged in each of the embedding areas.

10. A pressure sensing system, characterized in that: include: A power supply, wherein the power supply is electrically connected to the flexible piezoresistive sensor for temperature and humidity compensation as described in any one of claims 1 to 9 and a display component, and the display component can display the resistance value of the flexible piezoresistive sensor for temperature and humidity compensation accordingly.

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