An electric field measurement sensor

Abstract

The present invention discloses an electric field measurement sensor, which includes an insulating substrate, an electret, and a detection structure located on one side of the insulating substrate; the electret includes a positive electret and a negative electret, and the positive electret and the negative electret form an electrostatic field; the detection structure is arranged between the positive electret and the negative electret and has a first included angle with the first direction, and the first included angle is positively correlated with the electrostatic field, and the first direction is the thickness direction of the insulating substrate; when the electric field measurement sensor is in a detection environment, there is a second included angle between the detection structure and the first direction, and the detection structure is used to determine the electric field detection information of the current detection environment according to the angle difference between the second included angle and the first included angle. Compared with the measurement sensors in the prior art, the electric field measurement sensor provided by the embodiments of the present invention has the advantages of simple structure and low preparation cost, and at the same time ensures accurate acquisition of the electric field detection information of the detection environment, and improves the working accuracy of the electric field measurement sensor.

Description

Technical Field

[0001] The present invention relates to the technical field of sensors, and in particular, to an electric field measurement sensor. Background Art

[0002] Sensors are widely used in industrial production and scientific research projects, such as the electric field environment detection of railway automatic systems, aircraft and spacecraft operations, the power frequency electric field distribution of high-voltage transmission lines, the electromagnetic shielding and compatibility of precision electronic devices, and so on. The magnitude of the electric field in the above environments directly affects normal work and research, so the measurement of the electric field is very important.

[0003] The electric field has two characteristics: frequency and field strength. Classified by frequency, there are mainly electrostatic fields, low-frequency electric fields, and high-frequency electric fields. In each frequency category, there are strong electric fields and weak electric fields according to the electric field strength. According to the frequency characteristics of the electric field, there are mainly three types of electric field sensors: electrostatic field sensors, low-frequency alternating current electric field sensors, and high-frequency alternating current electric field sensors. The measurement of the electrostatic field is relatively simple. Currently, in the low-frequency band, the measurement is mainly based on the electromagnetic induction principle of the antenna, and in the high-frequency band, the electro-optic effect of the crystal is mostly used to measure the electric field; both need to be transmitted through the optical fiber system and then processed subsequently. The system is complex, the sensitivity is not high, generally the volume is very large, it is not conducive to integration, and the cost is very high. Summary of the Invention

[0004] In view of this, an embodiment of the present invention provides an electric field measurement sensor, which is used to solve the disadvantages of the existing measurement sensor with low sensitivity and high cost, and ensure the working accuracy of the electric field measurement sensor.

[0005] In a first aspect, an electric field measurement sensor provided by an embodiment of the present invention includes an insulating substrate, and an electret and a detection structure located on one side of the insulating substrate;

[0006] The electret includes a positive electret and a negative electret, and the positive electret and the negative electret form an electrostatic field;

[0007] The detection structure is disposed between the positive electret and the negative electret, and there is a first included angle with the first direction. The first included angle is positively correlated with the electrostatic field, and the first direction is the thickness direction of the insulating substrate;

[0008] When the electric field measurement sensor is in a detection environment, there is a second included angle between the detection structure and the first direction. The detection structure is used to determine the electric field detection information of the current detection environment according to the angle difference between the second included angle and the first included angle.

[0009] Optionally, the detection structure includes a cantilever beam and a piezoelectric layer that are attached, and the piezoelectric layer is located between the cantilever beam and the positive electret or the negative electret;

[0010] The cantilever beam includes a bottom surface and a top surface which are oppositely arranged, and the bottom surface is connected to the insulating substrate.

[0011] Optionally, the area of the bottom surface is larger than the area of the top surface.

[0012] Optionally, along the first direction, the height of the cantilever beam is H1;

[0013] The distance between the cantilever beam and the positive electret is L1, and the distance between the cantilever beam and the negative electret is L2;

[0014] Wherein, H1 ≤ L1 and H1 ≤ L2.

[0015] Optionally, the distance between the cantilever beam and the positive electret is equal to the distance between the cantilever beam and the negative electret.

[0016] Optionally, the detection structure further includes a mass block,

[0017] The mass block is located on the side of the cantilever beam away from the piezoelectric layer, and the mass block is in contact with the top surface.

[0018] Optionally, the electric field measurement sensor operates in a first detection environment, the detection structure includes a first mass block, and the mass of the first mass block is the first mass;

[0019] The electric field measurement sensor operates in a second detection environment, the detection structure includes a second mass block, and the mass of the second mass block is the second mass;

[0020] Wherein, the electric field frequency of the first detection environment is lower than the electric field frequency of the second detection environment, and the first mass is greater than the second mass.

[0021] Optionally, the density of the first mass block is the same as the density of the second mass block; the size of the first mass block is larger than the size of the second mass block;

[0022] Or the size of the first mass block is the same as the size of the second mass block; the density of the first mass block is greater than the density of the second mass block.

[0023] Optionally, the material of the electret includes an organic material or an inorganic material.

[0024] Optionally, the material of the piezoelectric layer includes an organic material or an inorganic material.

[0025] An electric field measurement sensor provided by an embodiment of the present invention, the electric field measurement sensor includes an insulating substrate, and an electret and a detection structure located on one side of the insulating substrate. Among them, the electret includes a positive electret and a negative electret, and a more stable and stronger electrostatic field is formed by the positive electret and the negative electret. And the detection structure is arranged between the positive electret and the negative electret, and there is a first included angle with the first direction. The first included angle is positively correlated with the electrostatic field, and the first direction is the thickness direction of the insulating substrate; when the electric field measurement sensor is in the detection environment, there is a second included angle between the detection structure and the first direction, and the detection structure is used to determine the electric field detection information of the current detection environment according to the angle difference between the second included angle and the first included angle. Among them, on the premise of the first included angle, the detection structure is more likely to sensitively generate the second included angle, ensuring accurate acquisition of the electric field detection information of the detection environment and improving the working accuracy of the electric field measurement sensor. At the same time, compared with the measurement sensors in the prior art, the electric field measurement sensor also has the advantages of simple structure and low preparation cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the introduced drawings are only the drawings of a part of the embodiments to be described by the present invention, rather than all the drawings. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained according to these drawings.

[0027] Figure 1 It is a schematic structural diagram of an electric field measurement sensor provided by an embodiment of the present invention;

[0028] Figure 2 It is a schematic structural diagram of another electric field measurement sensor provided by an embodiment of the present invention;

[0029] Figure 3 It is a top view of a cantilever beam provided by an embodiment of the present invention;

[0030] Figure 4 For Figure 3 a schematic cross-sectional structure diagram along the section line A-A' in

[0031] Figure 5 It is a schematic structural diagram of another electric field measurement sensor provided by an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0032] To make the objectives, technical solutions, and advantages of the present invention clearer, the following will, in conjunction with the accompanying drawings in the embodiments of the present invention, fully describe the technical solutions of the present invention through specific implementation manners. Apparently, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0033] Figure 1 It is a schematic structural diagram of an electric field measurement sensor provided by an embodiment of the present invention. Figure 1 It is a schematic structural diagram of an electric field measurement sensor provided by an embodiment of the present invention. Refer to Figure 1 and Figure 2 As shown, the electric field measurement sensor 10 provided by the embodiment of the present invention includes an insulating substrate 100, an electret 200, and a detection structure 300 located on one side of the insulating substrate 100; the electret 200 includes a positive electret 210 and a negative electret 220, and the positive electret 210 and the negative electret 220 form an electrostatic field a; the detection structure 300 is disposed between the positive electret 210 and the negative electret 220, and there is a first included angle b with the first direction X. The first included angle b is positively correlated with the electrostatic field a, and the first direction X is the thickness direction of the insulating substrate 100; when the electric field measurement sensor 10 is in the detection environment, there is a second included angle d between the detection structure 300 and the first direction X, and the detection structure 300 is used to determine the electric field detection information of the current detection environment according to the angle difference between the second included angle d and the first included angle b.

[0034] Among them, the electric field measurement sensor 10 is used to detect the ambient electric field, and its ambient electric field can be an electrostatic field, a low-frequency alternating current electric field, and a high-frequency alternating current electric field. The embodiments of the present invention have no specific limitations in this regard. Further, the electric field measurement sensor 10 includes an insulating substrate 100, an electret 200, and a detection structure 300, and the electret 200 and the detection structure 300 are disposed on the insulating substrate 100.

[0035] Specifically, the electret 200 includes a positive electret 210 and a negative electret 220, and an electrostatic field a is formed between the positive electret 210 and the negative electret 220, that is, the electrostatic field a is generated before the electric field measurement sensor 10 detects the detection environment. Refer to Figure 1 As shown, the electrostatic field a is exemplarily represented by multiple dotted lines in the figure. The number of dotted lines in the figure has no actual meaning and is only used to show the area of the electrostatic field a formed by the electret 200. Further, compared with ordinary polar body materials, the electret 200 can generate a more stable electrostatic field, and the field strength of the electrostatic field is greater.

[0036] Further, the detection structure 300 is disposed between the positive electret 210 and the negative electret 220, that is, the detection structure 300 is disposed in the electrostatic field a. Under the action of the force of the electrostatic field a, the detection structure 300 will deflect even when the detection environment is not detected. The deflection presentation mode can be that there is an included angle between the detection structure 300 and the first direction X. Taking the first included angle b as an example for illustration. In other words, the existing deflection of the detection structure 300 can be considered as electrostatic bias, that is, the electrostatic deflection generated by the detection structure 300 under the action of the electrostatic field a, and the magnitude of the first included angle b is positively correlated with the electrostatic field a. Exemplarily, the stronger the field strength of the electrostatic field a, the larger the first included angle b. Refer to Figure 1 As shown, the first included angle b is the included angle between the tangent line at point c in the detection structure 300 and the first direction X. The first included angle b can also be any point other than point c in the detection structure 300. The embodiments of the present invention do not specifically limit this.

[0037] Further, refer to Figure 1 As shown, when there is a first included angle b in the detection structure 300, that is, when the detection structure 300 already has a deflection, the electric field measurement sensor 10 is then disposed in the detection environment to detect the electric field of the detection environment, that is, to measure the intensity and frequency of the electric field, etc., and the electric field information of the detection environment can be measured more sensitively and accurately. Specifically, under the electrostatic field a generated by the detection structure 300 inside the electric field measurement sensor 10, the detection structure 300 is already in a biased state, that is, an unstable limit state. Under the condition of a new external force, the deflection amplitude and frequency of the detection structure 300 will be more obvious. Therefore, in this case, if the electric field where the detection structure 300 is located changes, the detection structure 300 will be more easily affected by the force brought by the electric field, resulting in a larger deflection of the detection structure 300. The presentation mode of the larger deflection can be that there is a new included angle between the detection structure 300 and the first direction X. Taking the second included angle d as an example for illustration. It should be noted that if the electric field of the detection environment is an electrostatic field, the detection structure 300 only presents a new deflection angle; if the electric field of the detection environment is a low-frequency alternating current field or a high-frequency alternating current field, the detection structure 300 presents vibration based on the first included angle b. Selecting a certain moment, the detection structure 300 also presents a new deflection angle. The embodiments of the present invention do not specifically limit this.

[0038] Refer to Figure 2 As shown, and Figure 2The detection structure 300 shown by the dashed line in the figure is a schematic diagram of the position at the second included angle d. It should be noted that both the first included angle a and the second included angle b are the included angles between the tangent line at point c in the detection structure 300 and the first direction X. Further, the detection structure 300 can reflect the electric field detection information of the current detection environment according to the angle difference between the second included angle d and the first included angle b. The electric field detection information can be the electric field strength. Similarly, the electric field frequency of the detection environment can also be reflected according to the vibration frequency of the detection structure 300 in the detection environment. Generally speaking, when there is already the first included angle b, that is, under the condition of electrostatic bias, the detection structure 300 can feedback the electric field information in the detection environment more accurately, that is, the sensitivity of the electric field measurement sensor 10 is higher. That is, no matter what type and magnitude the detected environmental electric field is, the electric field measurement sensor 10 provided by the embodiments of the present invention can accurately measure. At the same time, the electret 200 and the detection structure 300 are prepared on the insulating substrate 100, which reflects that the structure of the electric field measurement sensor 10 is simple and its manufacturing cost is also relatively low.

[0039] Further, the electric field measurement sensor 10 is arranged in a vacuum environment condition to detect the electric field of the detection environment, so as to avoid the influence of external water vapor, dust and damping force in the air on the measurement accuracy of the electric field measurement sensor 10 and ensure the measurement effect of the electric field measurement sensor 10.

[0040] In summary, the embodiments of the present invention provide an electric field measurement sensor. The detection structure is arranged between a positive electret and a negative electret and has a first included angle with the first direction; when the measurement sensor is in the detection environment, there is a second included angle between the detection structure and the first direction, and the detection structure is used to determine the electric field detection information of the current detection environment according to the angle difference between the second included angle and the first included angle. Compared with the measurement sensors in the prior art, the electric field measurement sensor provided by the embodiments of the present invention has the advantages of simple structure and low manufacturing cost. At the same time, it can accurately obtain the electric field detection information of the detection environment and improve the working accuracy of the electric field measurement sensor.

[0041] Figure 3 This is a top view of a cantilever beam provided by an embodiment of the present invention. Refer to Figure 1 and Figure 3 As shown, the detection structure 300 includes a cantilever beam 310 and a piezoelectric layer 320 which are attached to each other. The piezoelectric layer 320 is located between the cantilever beam 310 and the positive electret 210 or the negative electret 220; the cantilever beam 310 includes a bottom surface 310A and a top surface 310B which are oppositely arranged, and the bottom surface 310A is connected to the insulating substrate 100.

[0042] Specifically, the detection structure 300 includes a cantilever beam 310. The cantilever beam 310 is made of a conductive material, and the cantilever beam 310 is deflected or vibrated to different degrees under different electric fields. That is, under the electrostatic field a generated by the electret 200, a deflection presenting a first angle b with the first direction X is formed, and under the electric field of the detection environment, a deflection presenting a second angle d with the first direction X is formed. The intensity of the electric field is reflected from the difference in the deflection angles of the cantilever beam 310, and corresponding vibrations can also be generated when the electric field is at different frequencies, so that the frequency of the electric field is reflected by the vibration frequency of the cantilever beam 310.

[0043] Furthermore, the detection structure 300 further includes a piezoelectric layer 320. The piezoelectric layer 320 is attached to the cantilever beam 310. When the cantilever beam 310 is deflected and vibrated under different electric field environments, the piezoelectric layer 320 moves together with the cantilever beam 310, such as stretching, contracting or vibrating. Further, according to the piezoelectric effect, the piezoelectric layer 320 can cause the internal charge to flow to form an electrical signal according to its motion state, realizing the conversion of mechanical energy into electrical energy, and the piezoelectric layer 320 can output the converted electrical signal through a connecting wire to realize the detection of the electric field by the electric field measurement sensor 10.

[0044] Furthermore, referring to Figure 3 as shown, the cantilever beam 310 includes a bottom surface 310A and a top surface 310B which are oppositely arranged. The bottom surface 310A is connected to the insulating substrate 100, that is, the bottom surface 310A of the cantilever beam 310 is a fixed end and does not move in position, while the top surface 310B moves along the direction of the electric field to realize the movement of the cantilever beam 310. It should be noted that the bottom surface 310A and the top surface 310B are part of the cantilever beam 310, so the bottom surface 310A and the top surface 310B are of the same material, Figure 3 and different fillings in

[0045] Figure 4 are only used to indicate different positions, not different materials. Figure 3 is a schematic cross-sectional structure diagram along the section line A-A' in Figure 3 and Figure 4 as shown, the area of the bottom surface 310A is larger than the area of the top surface 310B.

[0046] Specifically, the bottom surface 310A of the cantilever beam 310 is connected to the insulating substrate 100, and the cantilever beam 310 moves with different amplitudes and frequencies under different electric field environments. To ensure that the cantilever beam 310 is more easily affected by the electric field force to move and to ensure the stable connection between the cantilever beam 310 and the insulating substrate 100, the area of the top surface 310B that is not connected to the insulating substrate 100 is set to be smaller, and the area of the bottom surface 310A connected to the insulating substrate 100 is larger. Thus, while ensuring that the mass of the cantilever beam 310 can be smaller and the damping force received is smaller, it can also ensure that the cantilever beam 310 is stably arranged on the insulating substrate 100. Exemplarily, referring to Figure 4 In [reference], from the cross-sectional schematic diagram of the cantilever beam 310, it can be seen that the cross-section of the cantilever beam 310 can be a trapezoid. The upper side of the trapezoid is a part of the top surface 310A, and the lower side of the trapezoid is a part of the bottom surface 310B. This further proves that the area of the bottom surface 310A is larger than the area of the top surface 310B, thereby ensuring the stable arrangement of the cantilever beam 310 and at the same time ensuring the measurement accuracy of the electric field measurement sensor 10.

[0047] Figure 5 As shown in the schematic structural diagram of another electric field measurement sensor provided by an embodiment of the present invention, along the first direction X, the height of the cantilever beam 310 is H1; the distance between the cantilever beam 310 and the positive electret 210 is L1, and the distance between the cantilever beam 310 and the negative electret 220 is L2; wherein, H1 ≤ L1 and H1 ≤ L2.

[0048] Among them, during the working process of the electric field measurement sensor 10, the cantilever beam 310 will deflect and vibrate with different amplitudes in the space between the positive electret 210 and the negative electret 220. To ensure the error-free operation of the electric field measurement sensor 10, it is necessary to ensure that the cantilever beam 310 does not contact the electret 200 during the movement. Referring to Figure 5 As shown, the height of the cantilever beam 310 is H1. Then the height H1 of the cantilever beam 310 is less than the distance L1 between the cantilever beam 310 and the positive electret 210, and at the same time the height H1 of the cantilever beam 310 is less than the distance L2 between the cantilever beam 310 and the negative electret 220. It should be noted that Figure 5 [reference] is used to represent the state of the cantilever beam 310 without electrostatic biasing. Specifically, the height of the cantilever beam 310 and the distance between it and the electret 200 are not specifically limited in the embodiments of the present invention.

[0049] Continuing to refer to Figure 5 As shown, the distance between the cantilever beam 310 and the positive electret 210 is equal to the distance between the cantilever beam 310 and the negative electret 220.

[0050] Further, the distance between the cantilever beam 310 and the positive electret 210 is L1, and the distance between the cantilever beam 310 and the negative electret 220 is L2. When L1 = L2, that is, when the cantilever beam 310 is located at the middle position between the positive electret 210 and the negative electret 220, it ensures that the electric field measurement sensor 10 is more regular and reduces the process preparation difficulty of the electric field measurement sensor 10.

[0051] Continuing to refer Figures 1 to 5 As shown, the detection structure 300 further includes a mass block 330. The mass block 330 is located on the side of the cantilever beam 310 away from the piezoelectric layer 320, and the mass block 330 is in contact with the top surface 310B.

[0052] Among them, the detection structure 300 further includes a mass block 330. The mass block 330 can ensure that the electric field measurement sensor 10 measures the alternating current electric fields at different frequencies, such as high-frequency alternating current electric fields and low-frequency alternating current electric fields, more stably based on different weights. The embodiments of the present invention do not specifically limit the frequency of the electric field. Refer Figures 1 to 5 As shown, the mass block 330 is in contact with the top surface 310B of the cantilever beam 310.

[0053] Continuing to refer Figures 1 to 5 As shown, when the electric field measurement sensor 10 operates in the first detection environment, the detection structure 300 includes a first mass block 330, and the mass of the first mass block 330 is the first mass; when the electric field measurement sensor 10 operates in the second detection environment, the detection structure 300 includes a second mass block 330, and the mass of the second mass block 330 is the second mass; wherein, the electric field frequency of the first detection environment is lower than that of the second detection environment, and the first mass is less than the second mass.

[0054] Exemplarily, the electric field frequency of the first detection environment is lower than that of the second detection environment. To ensure the stable and accurate operation of the electric field measurement sensor 10, the weight of the mass block 330 selected in the first detection environment is less than the weight of the mass block 330 selected in the second detection environment. Specifically, when the electric field measurement sensor 10 operates in the first detection environment, the detection structure 300 includes a first mass block 330, and the mass of the first mass block 330 is the first mass, then the first mass is less than the second mass. Based on the specific electric field frequency and the mass size of the mass block 330, the embodiments of the present invention do not specifically limit this.

[0055] Further, the density of the first mass block is the same as that of the second mass block; the size of the first mass block is smaller than that of the second mass block; or the size of the first mass block is the same as that of the second mass block; the density of the first mass block is less than that of the second mass block.

[0056] Among them, the mass of the mass block 330 can depend on the density and size of the mass block 330. Specifically, the mass of the first mass block is less than that of the second mass block. When the densities of the first mass block and the second mass block are the same, the size of the first mass block can be set to be smaller than that of the second mass block. Similarly, when the sizes of the first mass block and the second mass block are the same, the density of the first mass block can be selected to be less than that of the second mass block.

[0057] Continue to refer to Figures 1 to 5 As shown, the material of the electret 200 includes an organic material or an inorganic material.

[0058] Specifically, the electret 200 can be prepared with an inorganic material, and a stable electrostatic field a can exist between the positive electret 210 and the negative electret 220. Similarly, the electret 200 can also be prepared with an organic material, and the organic material has the advantages of storing a large amount of electric charge and storing the electric charge for a long time, that is, the electric field strength formed between the positive electret 210 and the negative electret 220 prepared with the organic material is greater and the duration is longer.

[0059] Continue to refer to Figures 1 to 5 As shown, the material of the piezoelectric layer 320 includes an organic material or an inorganic material.

[0060] Specifically, the piezoelectric layer 320 can be prepared with an inorganic material, and the piezoelectric layer 320 prepared with the inorganic material has a high sensitivity to the conversion between mechanical energy and electrical energy, ensuring the stability of the operation of the electric field measurement sensor 10. Further, the piezoelectric layer 320 can also be prepared with an organic material, and the piezoelectric layer 320 prepared with the organic material has the advantages of easy control of parameters during the preparation process and low preparation cost.

[0061] Note that the above is only the preferred embodiment of the present invention and the technical principles applied. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described here, and various obvious changes, re-adjustments, combinations with each other and substitutions can be made by those skilled in the art without departing from the protection scope of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments only. Without departing from the concept of the present invention, more other equivalent embodiments can be included, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. An electric field measurement sensor, characterized in that, It includes an insulating substrate, an electret, and a detection structure located on one side of the insulating substrate; The electret includes a positive electret and a negative electret, and the positive electret and the negative electret form an electrostatic field; The detection structure is disposed between the positive electret and the negative electret, and there is a first included angle with the first direction. The first included angle is positively correlated with the electrostatic field, and the first direction is the thickness direction of the insulating substrate; When the electric field measurement sensor is in a detection environment, there is a second included angle between the detection structure and the first direction, and the detection structure is used to determine the electric field detection information of the current detection environment according to the angle difference between the second included angle and the first included angle; Wherein, the detection structure includes a cantilever beam and a piezoelectric layer disposed in a fitting manner, and the piezoelectric layer is located between the cantilever beam and the positive electret or the negative electret; the cantilever beam includes a bottom surface and a top surface disposed opposite to each other, and the bottom surface is connected to the insulating substrate; the area of the bottom surface is larger than the area of the top surface; Along the first direction, the height of the cantilever beam is H1; The distance between the cantilever beam and the positive electret is L1, and the distance between the cantilever beam and the negative electret is L2; Wherein, H1≤L1 and H1≤L2; The distance between the cantilever beam and the positive electret is equal to the distance between the cantilever beam and the negative electret.

2. The electric field measurement sensor according to claim 1, wherein The detection structure further includes a mass block, The mass block is located on the side of the cantilever beam away from the piezoelectric layer, and the mass block is in contact with the top surface.

3. The electric field measurement sensor according to claim 2, wherein When the electric field measurement sensor operates in a first detection environment, the detection structure includes a first mass block, and the mass of the first mass block is the first mass; When the electric field measurement sensor operates in a second detection environment, the detection structure includes a second mass block, and the mass of the second mass block is the second mass; Wherein, the electric field frequency of the first detection environment is lower than the electric field frequency of the second detection environment, and the first mass is less than the second mass.

4. The electric field measurement sensor according to claim 3, wherein The density of the first mass block is the same as the density of the second mass block; the size of the first mass block is smaller than the size of the second mass block; Or the size of the first mass block is the same as the size of the second mass block; the density of the first mass block is less than the density of the second mass block.

5. The electric field measurement sensor according to claim 1, wherein The material of the electret includes an organic material or an inorganic material.

6. The electric field measurement sensor according to claim 1, wherein The material of the piezoelectric layer includes an organic material or an inorganic material.

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