Active vibration reduction sample table

Abstract

The invention relates to the technical field of detection instruments, and provides an active vibration reduction sample table which comprises a sample table body used for bearing a test sample; the at least one Z-axis piezoelectric actuator is arranged at the bottom of the sample table; the at least one X-axis piezoelectric actuator is arranged at the top of the Z-axis piezoelectric actuator; the at least one Y-axis piezoelectric actuator is arranged at the bottom of the Z-axis piezoelectric actuator; and the vibration meter is arranged on the sample table and is used for measuring a vibration signal of the sample table and inputting the vibration signal to the Z-axis piezoelectric actuator, the Y-axis piezoelectric actuator and the X-axis piezoelectric actuator, so that the Z-axis piezoelectric actuator, the Y-axis piezoelectric actuator and the X-axis piezoelectric actuator carry out vibration correction on vibration received by the sample table according to the vibration signal. The vibration influence of the external environment on the sample can be actively reduced. Compared with an existing vibration isolation structure of a measuring instrument which can only realize micron-scale vibration at the sample stage, the vibration at the sample stage can be improved to nano-scale by using the scheme.

Description

Technical Field

[0001] The present application relates to the technical field of detection instruments, in particular to the technical field of detection instruments requiring a cold source, and specifically to an active vibration reduction sample stage. Background Art

[0002] In some testing requirements, it is necessary to reduce the impact of external vibration of the test environment on the tested sample to a certain level in order to detect the performance of the tested sample as accurately as possible.

[0003] The vibration isolation structure provided by the existing testing device can only achieve micron-level vibration at the sample stage, which is difficult to meet user needs. On the other hand, the existing vibration isolation structures all provide passive vibration reduction. In summary, the prior art lacks a device that can actively reduce the vibration received by the sample in the detection scenario and has a more significant shock absorption effect. Summary of the invention

[0004] The present invention provides an active vibration reduction sample stage to solve the problem that the sample measuring device in the prior art is easily affected by the vibration of the measuring external environment and has too low measurement accuracy.

[0005] In order to solve at least one of the above problems existing in the prior art, the present application provides an active vibration reduction sample stage, comprising:

[0006] A sample stage, used to carry the test sample;

[0007] At least one Z-axis piezoelectric actuator, disposed at the bottom of the sample stage;

[0008] at least one X-axis piezoelectric actuator, disposed on top of the Z-axis piezoelectric actuator;

[0009] At least one Y-axis piezoelectric actuator, disposed at the bottom of the Z-axis piezoelectric actuator;

[0010] A vibrometer is disposed on the sample stage, and is used to measure a vibration signal of the sample stage, and input the vibration signal to the Z-axis piezoelectric actuator, the Y-axis piezoelectric actuator, and the X-axis piezoelectric actuator, so that the Z-axis piezoelectric actuator, the Y-axis piezoelectric actuator, and the X-axis piezoelectric actuator perform vibration correction on the vibration received by the sample stage according to the vibration signal.

[0011] In some embodiments of the present application, the Y-axis piezoelectric actuator and the X-axis piezoelectric actuator are driven in an opposing push-pull manner.

[0012] In some embodiments of the present application, the Y-axis piezoelectric actuator has opposite polarity to the X-axis piezoelectric actuator.

[0013] In some embodiments of the present application, the number of the X-axis piezoelectric actuators is two, which are symmetrically arranged on both sides of the top of the Z-axis piezoelectric actuator.

[0014] In some embodiments of the present application, the number of the Y-axis piezoelectric actuators is two, which are symmetrically arranged on both sides of the bottom of the Z-axis piezoelectric actuator.

[0015] In some embodiments of the present application, an active vibration reduction sample stage further includes:

[0016] The Z-axis bottom support is arranged at the bottom of the Z-axis piezoelectric actuator.

[0017] In some embodiments of the present application, an active vibration reduction sample stage further includes:

[0018] The Y-axis piezoelectric actuator support is connected to the Z-axis bottom support and is used to support the Y-axis piezoelectric actuator.

[0019] In some embodiments of the present application, an active vibration reduction sample stage further includes:

[0020] The outer frame is a box-shaped structure, which is used to wrap the Z-axis piezoelectric actuator, the X-axis piezoelectric actuator, the Y-axis piezoelectric actuator, the Z-axis bottom support and the Y-axis piezoelectric actuator support; and the sample stage is suspended on the upper surface of the box-shaped structure.

[0021] In some embodiments of the present application, the vibrometer is a grating ruler.

[0022] In some embodiments of the present application, the main scale of the grating ruler is arranged on a bracket of the sample stage, or on a support of the Y-axis piezoelectric actuator;

[0023] The reading head of the grating ruler is arranged on the sample platform.

[0024] From the above description, it can be seen that an active shock-absorbing sample table provided in an embodiment of the present application includes: a sample table for carrying a test sample; at least one Z-axis piezoelectric actuator, arranged at the bottom of the sample table; at least one X-axis piezoelectric actuator, arranged at the top of the Z-axis piezoelectric actuator; at least one Y-axis piezoelectric actuator, arranged at the bottom of the Z-axis piezoelectric actuator; a vibrometer, arranged on the sample table, for measuring the vibration signal of the sample table, and inputting the vibration signal to the Z-axis piezoelectric actuator, the Y-axis piezoelectric actuator and the X-axis piezoelectric actuator, so that the Z-axis piezoelectric actuator, the Y-axis piezoelectric actuator and the X-axis piezoelectric actuator can perform vibration correction on the vibration received by the sample table according to the vibration signal.

[0025] The active vibration-damping sample stage provided in the present application has a better vibration isolation effect. Compared with the vibration isolation structure of the existing measuring instruments which can only achieve micrometer-level vibration at the sample stage, the use of this solution can improve the vibration at the sample to the nanometer level. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the prior art descriptions. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0027] Figure 1 This is a schematic diagram of the motion structure of an active vibration-absorbing sample stage on the X and Z axes according to an embodiment of the present application.

[0028] Figure 2 This is a schematic diagram of the motion structure of an active vibration-absorbing sample stage on the Y and Z axes according to an embodiment of the present application. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] It should be noted that the terms "including" and "having" in the specification and claims of the present application and the above-mentioned drawings and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices. In the absence of conflict, the embodiments in the present application and the features in the embodiments may be combined with each other. The present application will be described in detail below with reference to the drawings and in combination with the embodiments.

[0031] The patent application with publication number CN114624473A discloses a closed-loop probe station, which uses a bellows to avoid direct contact between the cold source and the sample stage / sample cavity where the object to be measured is located, so as to reduce the vibration of the cold source driving the vibration of the object to be measured and related components; the cold amount transfer between the cold source and the object to be measured is realized by the cold copper braid, so as to reduce the influence of the vibration of the cold source on the object to be measured; the cold source is set on a separate support frame to avoid the cold source driving the whole machine to vibrate. However, the above scheme can only reduce the vibration of the object to be measured, so its reduction is limited, and the cold source (GM refrigerant) will cause micron-level vibration at the sample stage, thereby failing to meet the higher precision detection requirements of the object to be measured.

[0032] Based on this, and in order to solve at least one of the above-mentioned problems existing in the prior art, an embodiment of the present application provides an active vibration reduction sample stage. Figure 1 Schematic diagram of an active vibration reduction sample stage according to an embodiment of the present application. Figure 1 as well as Figure 2 As shown, an active vibration reduction sample stage comprises:

[0033] A sample stage, used to carry the test sample;

[0034] At least one Z-axis piezoelectric actuator, disposed at the bottom of the sample stage;

[0035] at least one X-axis piezoelectric actuator, disposed on top of the Z-axis piezoelectric actuator;

[0036] At least one Y-axis piezoelectric actuator, disposed at the bottom of the Z-axis piezoelectric actuator;

[0037] A vibrometer is disposed on the sample stage, and is used to measure a vibration signal of the sample stage, and input the vibration signal to the Z-axis piezoelectric actuator, the Y-axis piezoelectric actuator, and the X-axis piezoelectric actuator, so that the Z-axis piezoelectric actuator, the Y-axis piezoelectric actuator, and the X-axis piezoelectric actuator perform vibration correction on the vibration received by the sample stage according to the vibration signal.

[0038] From the above description, it can be seen that an active shock-absorbing sample table provided in an embodiment of the present application includes: a sample table for carrying a test sample; at least one Z-axis piezoelectric actuator, arranged at the bottom of the sample table; at least one X-axis piezoelectric actuator, arranged at the top of the Z-axis piezoelectric actuator; at least one Y-axis piezoelectric actuator, arranged at the bottom of the Z-axis piezoelectric actuator; a vibrometer, arranged on the sample table, for measuring the vibration signal of the sample table, and inputting the vibration signal to the Z-axis piezoelectric actuator, the Y-axis piezoelectric actuator and the X-axis piezoelectric actuator, so that the Z-axis piezoelectric actuator, the Y-axis piezoelectric actuator and the X-axis piezoelectric actuator can perform vibration correction on the vibration received by the sample table according to the vibration signal.

[0039] The active vibration-damping sample stage provided in the present application has a better vibration isolation effect. Compared with the vibration isolation structure of the existing measuring instruments which can only achieve micrometer-level vibration at the sample stage, the use of this solution can improve the vibration at the sample to the nanometer level.

[0040] Specifically, the sample stage is used to carry the sample, and the vibrometer is used to measure the vibration outside the test environment to which the sample stage (or the sample to be tested) is subjected, and the vibration signal is sent to the driving actuator, so that the driving actuator controls at least one of the Z-axis piezoelectric actuator, the X-axis piezoelectric actuator and the Y-axis piezoelectric actuator according to the vibration signal to realize the movement of the sample stage in three axes, X, Y and Z, thereby reducing the vibration impact of the external environment on the sample.

[0041] Furthermore, the sample stage is connected to the base plate in sequence through the Z-axis piezoelectric actuator, the Y-axis piezoelectric actuator, the X-axis piezoelectric actuator, and the movement of the sample stage in the three axes of X, Y, and Z can be achieved by controlling the voltage of the driving actuator. When the sample stage is small in size, a three-degree-of-freedom piezoelectric actuator is selected. The optional X-axis and Y-axis actuators can be reduced to one each.

[0042] The Z-axis piezoelectric actuator, X-axis piezoelectric actuator, and Y-axis piezoelectric actuator are devices that convert electrical energy into mechanical energy using the piezoelectric effect. The piezoelectric effect refers to the fact that certain materials generate an electric charge when subjected to mechanical stress, and conversely, if an electric field is applied to these materials, they will deform. Piezoelectric materials include: ceramics, such as barium titanate (BaTiO3) or lead zirconate titanate (PZT).

[0043] In addition, the above-mentioned three-degree-of-freedom piezoelectric actuator is a precision driving device that can move in three independent directions, using the piezoelectric effect to achieve high-precision displacement control. It can perform precise adjustments in multiple degrees of freedom simultaneously or independently.

[0044] Working principle of three-degree-of-freedom piezoelectric actuator: The core principle of three-degree-of-freedom piezoelectric actuator relies on the piezoelectric effect. Piezoelectric materials (such as PZT) will deform (elongate or compress) under the action of an electric field, and conversely, they will generate electric charges under mechanical stress. By applying voltage, the piezoelectric actuator can produce precise displacement in a specific direction.

[0045] Multi-DOF control: A three-DOF actuator has three degrees of freedom, usually three translational degrees of freedom (X, Y, Z axis) or three rotational degrees of freedom (rotation around X, Y, Z axis). In order to achieve precise control of multiple degrees of freedom, it is usually necessary to work together through multiple piezoelectric elements to control the movement of each degree of freedom separately. By applying different voltage signals to different piezoelectric elements, the displacement in different directions can be controlled separately.

[0046] A three-DOF actuator requires multiple independent voltage channels to drive each degree of freedom. The voltage control on each piezoelectric element is associated with the movement of the corresponding degree of freedom. For example, in an actuator used for positioning, the displacement of the X-axis and Y-axis may be controlled by two separate piezoelectric elements, while the control of the Z-axis may use another piezoelectric element.

[0047] The design of the three-degree-of-freedom piezoelectric actuator provided in this application adopts the following structures:

[0048] Parallel structure: The piezoelectric elements are arranged in parallel, and each element controls one degree of freedom. By adjusting the voltage on each piezoelectric element, the displacement of the actuator in each degree of freedom can be controlled. The advantages of this design are independent control and fast response.

[0049] Series structure: Multiple piezoelectric elements are connected into a series system. In this way, the overall deformation of the actuator can be precisely controlled in one direction. The series structure is suitable for large displacements in a specific direction or directions, but the control is relatively complex.

[0050] Composite structure: The composite structure combines the advantages of parallel and series connection to provide a large displacement range in multiple directions while maintaining high accuracy.

[0051] In some embodiments of the present application, see Figure 1 as well as Figure 2 The Y-axis piezoelectric actuator and the X-axis piezoelectric actuator are driven in an opposing push-pull manner. The Y-axis piezoelectric actuator and the X-axis piezoelectric actuator have opposite polarities.

[0052] Specifically, the X-axis and Y-axis are driven by two opposing actuators in an opposing push-pull manner, and the two have opposite polarities, that is, when one is driven to pull, the other is driven to contract. It can be understood that the opposing structure can reduce the occurrence of flipping, while the Z-axis uses one actuator. Furthermore, more actuators can be selected to achieve 6-DOF control.

[0053] It is understood that piezoelectric materials (such as PZT, barium titanate, etc.) have intrinsic polarity, which means that the atomic or molecular arrangement of the material has a certain electric dipole moment. When an external electric field is applied to the piezoelectric material, the electric dipole moment inside the material will rearrange, causing the material to deform. The working principle of the piezoelectric actuator is to use this phenomenon to displace the material by applying an electric field. Specifically:

[0054] Positive polarity: When the positive electrode of the piezoelectric actuator is connected to one end of the piezoelectric material and the negative electrode is connected to the other end, the direction of the electric field is consistent with the polarity direction of the material. At this time, the piezoelectric material will stretch (increase in size in the stretching direction) or compress perpendicular to the direction of the electric field.

[0055] Negative Polarity: If the electrodes are connected in the opposite direction to the original polarity of the material (i.e. the direction of the electric field is opposite to the polarity), the piezoelectric material will compress or shorten when an electric field is applied.

[0056] The polarity of the piezoelectric material (i.e. the direction of the electric dipole moment of the crystal) is determined during the manufacturing process. Different piezoelectric materials (such as barium titanate BaTiO 3 , lead zirconate titanate PZT, etc. have different polarity directions. During processing, these materials are usually "polarized", that is, the electric dipole moment inside the material is uniformly pointed in a certain direction through an external electric field.

[0057] Polarization: The polarization process is to place the piezoelectric material in a high electric field so that the electric dipole moment inside the material is aligned along the direction of the external electric field. After the electric field is removed, the polarized material still maintains a certain internal polarity. The polarity direction is consistent with the direction of the applied electric field.

[0058] Polarity direction: The polarity direction of each piezoelectric material is inherent and depends on the crystal structure of the material. In the design of piezoelectric actuators, controlling the direction and magnitude of the electric field can precisely control the deformation direction and displacement of the material.

[0059] The deformation of a piezoelectric actuator is closely related to the polarity of the applied electric field. The correct polarity setting is critical to the performance of the actuator, affecting the following aspects:

[0060] Displacement direction: When the direction of the electric field is consistent with the polarity direction of the material, the material will stretch; when it is opposite, the material will be compressed. By selecting different polarity controls, displacement in different directions can be achieved.

[0061] Deformation amplitude: When the same voltage is applied, the consistency or opposite direction of the electric field and the material polarity will affect the deformation amplitude of the actuator. The correct polarity setting can make the piezoelectric material respond to the electric field with maximum efficiency, thereby obtaining a larger displacement.

[0062] Actuator performance: Incorrect polarity setting may result in a smaller displacement output by the actuator or an incorrect direction, which may reduce the efficiency of the actuator. Reverse polarity connection may result in material damage or loss of function, or even permanent damage.

[0063] In practical applications, the piezoelectric actuator needs to control the polarity through a voltage signal. Preferably, this can be achieved in the following ways:

[0064] Direct current (DC) control: The polarity of the piezoelectric material is controlled directly by applying positive and negative voltages. When the voltage is positive, the material deforms in one direction; when the voltage is negative, the material deforms in the opposite direction.

[0065] AC voltage control: By adjusting the frequency and voltage amplitude, the oscillation behavior of the actuator can be controlled. Frequency changes can change the vibration frequency of the piezoelectric material, thereby affecting the displacement and response.

[0066] Controller Design: An accurate controller can dynamically adjust the polarity of the voltage signal to precisely control the motion trajectory, velocity, and acceleration of the piezoelectric actuator.

[0067] The number of the X-axis piezoelectric actuators is two, which are symmetrically arranged on both sides of the top of the Z-axis piezoelectric actuator.

[0068] In some embodiments of the present application, see Figure 1 as well as Figure 2 There are two X-axis piezoelectric actuators, which are symmetrically arranged on both sides of the top of the Z-axis piezoelectric actuator.

[0069] In some embodiments of the present application, see Figure 1 as well as Figure 2 There are two Y-axis piezoelectric actuators, which are symmetrically arranged on both sides of the bottom of the Z-axis piezoelectric actuator.

[0070] In some embodiments of the present application, see Figure 1 as well as Figure 2 , an active vibration reduction sample stage, further comprising:

[0071] The outer frame is a box-type structure (it should be pointed out that the box-type structure does not have a seal, that is, the box-type structure does not have a box cover), which is used to wrap the Z-axis piezoelectric actuator, the X-axis piezoelectric actuator, the Y-axis piezoelectric actuator, the Z-axis bottom support and the Y-axis piezoelectric actuator support; and the sample stage is suspended on the upper surface of the box-type structure.

[0072] In some embodiments of the present application, the vibrometer is a grating ruler.

[0073] An optical linear encoder (Optical Scale) is a sensor used to accurately measure displacement, position, and speed. It uses optical principles to achieve high-precision displacement detection and is usually composed of a grating with precise spacing and a matching readout system. It can provide high-resolution and high-precision displacement data and is suitable for applications that require micron or nanometer accuracy.

[0074] The working principle of the grating ruler is based on the interference, diffraction or reflection effect of light. The grating ruler consists of the following main parts:

[0075] Grating: The grating is the core part of the scale, usually a transparent or reflective stripe pattern with regular, uniform spacing. The spacing of the stripes (also called the grating period) determines the resolution of the scale. Gratings can be transparent or reflective, and the most common types are reflection gratings and transmission gratings.

[0076] Light source: The light source provides a stable light beam, usually a laser or LED light source. After the light emitted by the light source passes through the grating, it forms a series of diffracted beams or reflected beams.

[0077] Photodetectors: Photodetectors (such as photodiodes, CCD or CMOS sensors) are used to detect the light beam after it passes through the grating. These detectors sense the intensity change of the light beam and thus obtain the displacement information.

[0078] Signal processing circuit: The signal processing circuit converts the optical signal obtained from the detector into an electronic signal, and then outputs the digital displacement data through encoding.

[0079] The workflow is as follows: The light source emits a stable light beam onto the grating. When the light beam passes through the grating, it will be diffracted or reflected to form multiple light beams. The detector receives these light beams and detects the position change of the grating based on the change in signal intensity. By analyzing the changes in the grating stripes, the position change of the grating relative to the detector is calculated to obtain the displacement data.

[0080] Grating rulers can be divided into different types according to the structure and measurement method of the grating:

[0081] Transmissive Encoder: This type of encoder uses a light-transmitting grating, and the light beam is detected by the sensor after passing through the grating stripes. Transmissive encoders are generally simpler and suitable for applications with lower precision requirements.

[0082] Reflective Encoder: In this type of encoder, the light beam is reflected back to the detector by a reflective grating. Reflective encoders are generally more resistant to contamination and have a longer service life, making them suitable for use in industrial environments.

[0083] Incremental Encoder: The output of an incremental encoder is a signal related to the displacement increment. Every time the grating moves a certain distance, the photodetector generates a pulse signal representing a certain displacement increment. By counting these pulses, the position can be calculated.

[0084] Absolute Encoder: An absolute encoder can provide absolute position values. Each position corresponds to a unique code. When the encoder moves, the output signal can directly represent the current position without the need to obtain relative displacement through pulse counting.

[0085] In some embodiments of the present application, the main scale of the grating ruler is arranged on a bracket of the sample stage, or on a support of the Y-axis piezoelectric actuator;

[0086] The reading head of the grating ruler is arranged on the sample platform.

[0087] Specifically, the main scale of the grating ruler is installed on the sample stage bracket or the support of the uniaxial actuator, and the reading head is installed on the sample stage, or the two are installed in opposite positions, so that the vibration state of the sample stage or the sample can be detected by the grating ruler, thereby controlling the aforementioned piezoelectric actuator, and the vibration at the sample can be improved to the nm level.

[0088] In some embodiments of the present application, the vibrometer may also be a laser vibrometer.

[0089] A laser vibrometer is an instrument that uses laser technology to measure the vibration of an object. It measures the vibration velocity, displacement and acceleration of the surface of an object in a non-contact manner. The working principle of a laser vibrometer is based on the laser Doppler effect. When a laser beam is irradiated onto the surface of a vibrating object, the frequency of the reflected laser beam changes, and this frequency change is proportional to the vibration velocity of the object. By measuring this frequency change, the laser vibrometer can calculate the vibration velocity of the object and further obtain vibration parameters such as displacement and acceleration. The main advantages of a laser vibrometer include:

[0090] Non-contact measurement: No contact with the object being measured is required, avoiding the interference and mass loading effects that may be introduced by traditional contact sensors.

[0091] High precision: Laser measurement technology has very high accuracy and can detect tiny vibrations.

[0092] High frequency response: It can measure high frequency vibrations and is suitable for application scenarios that require high frequency response.

[0093] Wide application: It is suitable for vibration measurement of various materials and surfaces, and is not limited by the surface state of the measured object.

[0094] In addition, when using a laser vibrometer, the following points should be noted: The reflectivity of the surface of the object being measured will affect the measurement accuracy, and it is necessary to spray a reflective film on the surface or use a reflective patch to improve the reflectivity. Factors such as ambient light and air turbulence may interfere with the laser beam and affect the measurement results, so it is necessary to measure in a relatively stable environment. The laser beam needs to be accurately aimed at the measurement point of the object being measured to ensure the accuracy of the measurement data.

[0095] In some embodiments of the present application, the active vibration reduction sample stage further includes:

[0096] An inertial sensor is arranged at the bottom of the main structure of the active vibration reduction sample stage; a measurement signal of the inertial sensor is used as one of the inputs of the vibration isolator control signal.

[0097] An inertial sensor is a device that can measure the acceleration and angular velocity of an object. It works based on the inertial characteristics of an object during motion, and usually relies on physical principles to measure the state of motion of an object. According to the different physical quantities measured, inertial sensors can be divided into:

[0098] Accelerometer: measures the linear acceleration of an object, usually in m / s 2 (meters per second squared). Accelerometers are typically able to measure acceleration in one or more directions.

[0099] Gyroscope: measures the angular velocity of an object, usually in rad / s (radians per second). Gyroscopes are used to sense the rotation rate and angle changes of an object.

[0100] These sensors can be manufactured using integrated circuit (IC) technology. Modern inertial sensors often integrate multiple sensors on the same chip to form an inertial measurement unit (IMU).

[0101] An accelerometer works by sensing the acceleration (i.e. the rate of change of velocity) of an object. Its working principle is usually based on the principle of inertia of a particle, that is, when the housing of the accelerometer is subjected to acceleration, the internal mass block (or sensing element) will be displaced relative to the housing. By measuring this displacement or strain, the acceleration can be calculated.

[0102] Piezoelectric accelerometer: Based on the piezoelectric effect, the movement of the mass generates an electrical signal that is proportional to the acceleration.

[0103] Capacitive accelerometer: The displacement of internal particles causes a change in capacitance, and the change in capacitance is proportional to the acceleration.

[0104] MEMS accelerometer: Based on micro-electromechanical system (MEMS) technology, it uses tiny mass blocks and suspension structures to sense the displacement generated by acceleration and convert it into an electrical signal.

[0105] Preferably, the present application selects IMU as an inertial sensor, which is a multi-sensor unit composed of an accelerometer, a gyroscope and sometimes a magnetometer, and is usually used for precise navigation and attitude control. It can provide three-dimensional acceleration, angular velocity and sometimes magnetic field information of an object.

[0106] The shock absorbing platform is arranged at the bottom of the inertial sensor and is used to cooperate with the inertial sensor to reduce the vibration of the main structure.

[0107] Specifically, a shock-absorbing platform is disposed on a tabletop, and the tabletop is provided with an active shock-absorbing sample table. It can be understood that by additionally arranging an inertial sensor and a shock-absorbing platform, the vibration effect of the external environment on the sample can be further reduced through the cooperation of the two.

[0108] From the above description, it can be seen that an active shock-absorbing sample table provided in an embodiment of the present application includes: a sample table for carrying a test sample; at least one Z-axis piezoelectric actuator, arranged at the bottom of the sample table; at least one X-axis piezoelectric actuator, arranged at the top of the Z-axis piezoelectric actuator; at least one Y-axis piezoelectric actuator, arranged at the bottom of the Z-axis piezoelectric actuator; a vibrometer, arranged on the sample table, for measuring the vibration signal of the sample table, and inputting the vibration signal to the Z-axis piezoelectric actuator, the Y-axis piezoelectric actuator and the X-axis piezoelectric actuator, so that the Z-axis piezoelectric actuator, the Y-axis piezoelectric actuator and the X-axis piezoelectric actuator can perform vibration correction on the vibration received by the sample table according to the vibration signal.

[0109] The active vibration-damping sample stage provided in the present application has a better vibration isolation effect. Compared with the vibration isolation structure of the existing measuring instruments which can only achieve micrometer-level vibration at the sample stage, the use of this solution can improve the vibration at the sample to the nanometer level.

[0110] In the description of this specification, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are 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 therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0111] The descriptions with reference to the terms "one embodiment", "a specific embodiment", "some embodiments", "for example", "example", "specific example", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. The order of steps involved in each embodiment is used to schematically illustrate the implementation of the present invention, and the order of steps therein is not limited and may be appropriately adjusted as needed.

[0112] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0113] Each embodiment in this specification is described in a progressive manner, and the same and similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment. In the description of this specification, the description of the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiment of this specification. In this specification, the schematic representation of the above terms does not necessarily target the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, in the absence of contradiction, a person skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0114] The above is only an example of the embodiment of the present specification and is not intended to limit the embodiment of the present specification. For those skilled in the art, the embodiment of the present specification may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the embodiment of the present specification shall be included in the scope of the claims of the embodiment of the present specification.

Claims

1. An active vibration reduction sample stage, characterized in that: include: A sample stage, used to carry the test sample; At least one Z-axis piezoelectric actuator, disposed at the bottom of the sample stage; at least one X-axis piezoelectric actuator, disposed on top of the Z-axis piezoelectric actuator; At least one Y-axis piezoelectric actuator, disposed at the bottom of the Z-axis piezoelectric actuator; A vibrometer is disposed on the sample stage, and is used to measure a vibration signal of the sample stage, and input the vibration signal to the Z-axis piezoelectric actuator, the Y-axis piezoelectric actuator, and the X-axis piezoelectric actuator, so that the Z-axis piezoelectric actuator, the Y-axis piezoelectric actuator, and the X-axis piezoelectric actuator perform vibration correction on the vibration received by the sample stage according to the vibration signal.

2. The active vibration reduction sample stage according to claim 1, characterized in that: The Y-axis piezoelectric actuator and the X-axis piezoelectric actuator are driven in an opposing push-pull manner.

3. The active vibration reduction sample stage according to claim 1, characterized in that: The Y-axis piezoelectric actuator has opposite polarity to the X-axis piezoelectric actuator.

4. The active vibration reduction sample stage according to claim 1, characterized in that: The number of the X-axis piezoelectric actuators is two, which are symmetrically arranged on both sides of the top of the Z-axis piezoelectric actuator.

5. The active vibration reduction sample stage according to claim 1, characterized in that: The number of the Y-axis piezoelectric actuators is two, which are symmetrically arranged on both sides of the bottom of the Z-axis piezoelectric actuator.

6. The active vibration reduction sample stage according to claim 1, characterized in that: Also includes: The Z-axis bottom support is arranged at the bottom of the Z-axis piezoelectric actuator.

7. The active vibration reduction sample stage according to claim 6, characterized in that: Also includes: The Y-axis piezoelectric actuator support is connected to the Z-axis bottom support and is used to support the Y-axis piezoelectric actuator.

8. The active vibration reduction sample stage according to claim 7, characterized in that: Also includes: The outer frame is a box-shaped structure, which is used to wrap the Z-axis piezoelectric actuator, the X-axis piezoelectric actuator, the Y-axis piezoelectric actuator, the Z-axis bottom support and the Y-axis piezoelectric actuator support; and the sample stage is suspended on the upper surface of the box-shaped structure.

9. The active vibration reduction sample stage according to claim 8, characterized in that: The vibrometer is a grating ruler.

10. The active vibration reduction sample stage according to claim 9, characterized in that: The main scale of the grating ruler is arranged on the bracket of the sample stage, or on the support of the Y-axis piezoelectric actuator; The reading head of the grating ruler is arranged on the sample platform.

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