Three-dimensional high-precision position measurement and manipulation method and device based on light suspended particles

Abstract

The application discloses a three-dimensional high-precision position measurement and control method and device based on light suspended micro-particles, and the device comprises a laser, a first spatial light modulator, a two-dimensional angle control system, a first reflector, a high-focusing first lens and a double-probing camera. The laser emits a first laser beam, the first spatial light modulator divides the first laser beam and controls the intensity of a second laser beam, the two-dimensional angle control system converts the second laser beam into a fourth laser beam which is controllable in two dimensions in a ZOY plane, the first reflector maps the fourth laser beam to an XOY plane, and the high-focusing first lens converges the fourth laser beam into a vertical upward optical trap to capture a microsphere; the double-probing camera probes the position or displacement of the microsphere in the ZOY plane and the XOY plane respectively. The application can realize high-precision spatial three-dimensional movement of the suspended microsphere through simple parameter adjustment, and has the advantages of large control range, high precision and non-contact.

Description

Technical Field

[0001] This invention relates to the fields of optical engineering and particle levitation technology, and in particular to a method and apparatus for high-precision three-dimensional position measurement and manipulation based on optically levied particles. Background Technology

[0002] Vacuum optical trap levitation sensing technology relies on the optical trap mechanism to non-contactly bind micron-sized particles in a vacuum environment. Utilizing their unique physical properties at the transition scale between classical and quantum domains, it achieves ultra-high sensitivity detection of physical quantities. When the suspended particles deviate from their equilibrium state due to external forces, the system analyzes their motion to deduce extremely weak force or acceleration signals. Compared to traditional force sensing methods, this technology significantly improves measurement sensitivity due to its advantages of no mechanical support, isolation from thermal noise, and extremely low mechanical loss, while also being easy to integrate and exhibiting good system stability.

[0003] In this system, suspended particles serve as the core sensing medium, and their performance directly determines the quality of the measurement results. As a highly sensitive sensing unit, this system has extremely stringent requirements for control precision. Therefore, achieving large-scale, high-precision three-dimensional manipulation of particles is not only a key step in the sensing process but also a decisive factor in ensuring the accuracy of weak force and acceleration measurements and improving the overall performance of the system.

[0004] Existing optical trap manipulation technologies typically employ multi-beam or mechanical displacement stages to measure and manipulate particles. However, these methods suffer from limitations in measurement and manipulation range, insufficient accuracy, or the introduction of mechanical noise, making it difficult to simultaneously meet the demands for large-scale, high-precision, and non-contact three-dimensional measurement and manipulation. Summary of the Invention

[0005] The purpose of this invention is to provide a method and device for high-precision three-dimensional position measurement and manipulation based on optically suspended microparticles. This invention achieves high-precision three-dimensional spatial position measurement and movement of suspended microspheres through simple parameter adjustments, offering advantages such as a large control range, high precision, and non-contact operation.

[0006] The technical solution of this invention: A three-dimensional high-precision position measurement and manipulation method based on optically levitated particles, comprising the following steps: Step 1: A first laser beam is generated by a laser, and the intensity of the first laser beam is modulated by a first spatial light modulator to generate a second laser beam with controllable intensity. Step 2: Input the second laser beam into the two-dimensional angle control system, which includes a second spatial light modulator and a third spatial light modulator; deflect the second laser beam in a first direction through the second spatial light modulator to generate a ninth laser beam; then deflect the ninth laser beam in a second direction orthogonal to the first direction through the third spatial light modulator to generate a fourth laser beam with adjustable direction. Step 3: After the fourth laser beam is reflected by the first reflecting mirror and focused by the high-focusing first lens, it forms a vertically upward optical trap in the capture area with adjustable focal position and light intensity to capture and suspend the microsphere. Step 4: Measure the three-dimensional position of the microsphere using the first and second detection cameras to obtain measurement data; Step 5: Based on the measurement data, the optical trap force distribution in the vertical direction of the optical trap is changed by adjusting the first spatial light modulator, thereby realizing the position control of the microsphere in the vertical direction; and / or the propagation direction of the fourth laser beam is changed by adjusting the two-dimensional angle control system, so that the focal point of the optical trap formed by the highly focused first lens moves in the XOY plane, thereby realizing the two-dimensional position control of the microsphere in the horizontal plane.

[0007] The above method, specifically step 5 includes: The second laser beam is received by the second spatial light modulator and divided into an eighth laser beam and a ninth laser beam. The ninth laser beam is deflected at an angle in the XOY plane. The third spatial light modulator receives the ninth laser beam and divides it into a fourth laser beam and a fifth laser beam, and deflects the fourth laser beam at an angle in the ZOX plane. The first reflector is used to convert the pointing control of the fourth laser beam in the ZOY plane into pointing control in the XOY plane, so that the intersection point of the fourth laser beam and the XOY plane can move arbitrarily in the plane.

[0008] The aforementioned method further includes: continuously measuring the position or displacement change of the microsphere in the ZOY plane using the first detection camera, and continuously measuring the position or displacement change of the microsphere in the XOY plane using the second detection camera; combining the measurement results of the first detection camera and the second detection camera to obtain the real-time position or displacement information of the microsphere in three-dimensional space, and performing closed-loop feedback control on the first spatial light modulator and / or the two-dimensional angle control system based on the real-time position or displacement information to correct the three-dimensional position of the microsphere.

[0009] The aforementioned method is applied to the three-dimensional position measurement and manipulation of the microspheres in a vacuum environment, a liquid environment, or a gaseous environment.

[0010] An apparatus for implementing the aforementioned method includes: A laser, used to emit the first laser beam; A first spatial light modulator is used to receive the first laser beam and split it into a second laser beam and a third laser beam, and to adjust the intensity of the second laser beam. A two-dimensional angle control system is used to receive the intensity-modulated second laser beam and convert it into a fourth laser beam with two-dimensional pointing control in the ZOY plane; The first reflector is used to switch the pointing control of the fourth laser beam from the ZOY plane to the XOY plane; A high-focusing first lens is used to receive the fourth laser beam reflected by the first reflector and to form a vertically upward optical trap for capturing the microsphere. A first detection camera is used to collect the scattered light from the microspheres to measure their position or displacement on the ZOY plane; The second detection camera is used to receive the scattered light after passing through the microsphere to measure its position or displacement on the XOY plane.

[0011] The aforementioned apparatus, wherein the two-dimensional angle control system comprises: A second spatial light modulator is used to receive the second laser beam, divide it into an eighth laser beam and a ninth laser beam, and deflect the ninth laser beam at an angle in the XOY plane. A third spatial light modulator is used to receive the ninth laser beam, split it into a fourth laser beam and a fifth laser beam, and deflect the fourth laser beam at an angle in the ZOX plane. The output beam control directions of the second spatial light modulator and the third spatial light modulator are orthogonal.

[0012] In the aforementioned device, the first reflector is set at a 45-degree spatial angle with the XOY plane, which is used to convert the arbitrary pointing control of the fourth laser beam in the ZOY plane into arbitrary pointing change in the XOY plane.

[0013] The aforementioned device also includes a first light barrier, a second light barrier, and a third light barrier; The first light barrier is used to absorb the third laser beam; The second light barrier is used to absorb the fifth laser beam; The third light barrier is used to absorb the eighth laser beam.

[0014] The aforementioned device also includes a second lens and a second reflecting mirror; The second lens is disposed between the microsphere and the second reflector to converge the scattered light; The second reflector is used to reflect the scattered light that has passed through the second lens to the second detection camera.

[0015] The aforementioned device also includes a container, in which the high-focusing first lens, the microsphere, and the second lens are placed, and the interior of the container is a vacuum environment, a gas environment, or a liquid environment.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention achieves high-precision, non-contact position measurement and manipulation of three degrees of freedom of suspended particles in a single-beam optical trap by independently controlling the light intensity (Z-axis) with one spatial light modulator and jointly controlling the beam angle (mapped to the X and Y axes by a reflector) with two orthogonal spatial light modulators. The manipulation range is large.

[0017] 2. This invention uses a single-path vertical optical trap for capture and performs measurement and control through pure optical modulation, avoiding complex mechanical movement or the introduction of other interference fields. It is particularly suitable for vacuum or isolated environments that are extremely sensitive to vibration and noise.

[0018] 3. The measurement and control optical path of the present invention and the controlled microsphere can be placed together in a sealed container, so that the device and method can be applied not only to the atmospheric environment, but also directly to the vacuum, specific gas or liquid environment, which greatly expands its application potential in basic physics research (such as vacuum sensing) and biochemical detection.

[0019] 4. The device of this invention incorporates a three-dimensional position measurement system based on dual cameras, which can monitor the movement of the microsphere in real time, providing a foundation for achieving rapid closed-loop feedback control and further improving the accuracy and stability of the operation. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of the device of the present invention; Figure 2 This is a schematic diagram of the structure of the two-dimensional angle control system of the present invention; Figure 3 This is a schematic diagram of the operation of a two-dimensional angle control system; Figure 4 This is a schematic diagram showing the positional changes of the microspheres under control.

[0021] Figure Labels L1, First laser beam; L2, Second laser beam; L3, Third laser beam; L4, Fourth laser beam; L5, Fifth laser beam; L8, Eighth laser beam; L9, Ninth laser beam; S1, Laser; S2, First spatial light modulator; S3, Two-dimensional angle control system; S4, First reflecting mirror; S5, High-focusing first lens; S6, Microsphere; S7, Second lens; S8, Second reflecting mirror; S9, Second detection camera; S10, First detection camera; S11, First light block; S12, Second light block; S13, Second spatial light modulator; S14, Third spatial light modulator; S15, Third light block; H1, Container. Detailed Implementation

[0022] The present invention will be further described below with reference to the accompanying drawings and embodiments, but this should not be construed as limiting the present invention.

[0023] Example: A three-dimensional high-precision position measurement and manipulation device based on optically levitated microparticles, such as... Figure 1 As shown, it includes: Laser S1: Used to generate a first laser beam L1 with high collimation, providing a laser source for the entire device.

[0024] The first spatial light modulator S2 is an acousto-optic modulator (AOM), model G&H3080-125, paired with a G&H3307 series RF driver. Its input port is coaxially connected to the output port of the laser S1, receiving the first laser beam L1 and splitting it into a second laser beam L2 for subsequent manipulation and a useless third laser beam L3. Simultaneously, the intensity of the second laser beam L2 can be continuously adjusted. The first optical block S11 is positioned perpendicular to the optical path in the direction of the third laser beam L3's emission from the first spatial light modulator S2, completely absorbing the third laser beam L3 to prevent stray light from interfering with subsequent optical paths.

[0025] Two-dimensional angle control system S3: such as Figure 2 As shown, it includes a second spatial light modulator S13 and a third spatial light modulator S14, and the output beam control directions of the second spatial light modulator S13 and the third spatial light modulator S14 are orthogonal, used to realize two-dimensional pointing control of the second laser beam L2 in the ZOY plane, generating a fourth laser beam L4. Wherein: The second spatial light modulator S13 is an acousto-optic modulator, model G&H3080-125, paired with a DR-DFA-MC driver. Its input port aligns with the L2 output direction of the first spatial light modulator S2, receiving the second laser beam L2 and splitting it into an eighth laser beam L8 and a ninth laser beam L9. The ninth laser beam L9 is then deflected in the XOY plane, with the angle between the undeflected and deflected beams being θ. XOYThe third light block S15 is positioned perpendicular to the optical path and is located at the emission direction of the eighth laser beam L8 from the second spatial light modulator S13. It is used to absorb the eighth laser beam L8 and eliminate stray light.

[0026] The third spatial optical modulator S14 uses the same acousto-optic modulator as the second spatial optical modulator S13, paired with a DR-DFA-MC driver. Its input port is coaxially aligned with the output direction of L9 of S13, receiving the ninth laser beam L9, splitting it into a fourth laser beam L4 and a fifth laser beam L5, and deflecting the fourth laser beam L4 in the ZOX plane. The angle between the undeflected and deflected beams is θ. ZOX Furthermore, the deflection direction is spatially orthogonal to the deflection direction of S13. The second light block S12 is positioned perpendicular to the optical path at the emission direction of the fifth laser beam L5 from the third spatial light modulator S14, and is used to absorb the fifth laser beam L5 and eliminate stray light.

[0027] The first reflecting mirror S4 is fixed at a 45-degree spatial angle with the XOY plane. It is used to convert the arbitrary pointing control of the fourth laser beam L4 in the ZOY plane into arbitrary pointing change in the XOY plane, so as to realize the pointing mapping of the laser beam from the vertical plane to the horizontal plane.

[0028] The high-focusing first lens S5 has its light inlet coaxially aligned with the reflected light path of the fourth laser beam L4 from the first reflecting mirror S4. This allows the converged fourth laser beam L4 to form a vertically upward single-path optical trap. The focal size of the optical trap matches the size of the microsphere S6, enabling contactless capture and levitation of the microsphere S6. The microsphere S6 is the core object of optical levitation manipulation, positioned at the focal point of the optical trap formed by the high-focusing first lens S5, and levitation is achieved through the balance between the optical trap force and gravity.

[0029] The second lens S7 is positioned in the direction of the scattered light emission from the microsphere S6 and is coaxial with the center of the microsphere S6. It is used to converge the scattered light transmitted through the microsphere S6 and improve the signal acquisition accuracy of the detection camera.

[0030] Second reflector S8: Located on the light-emitting side of second lens S7, at a 45° angle to the scattered light path, used to reflect the converged scattered light to the light-inlet of second detection camera S9.

[0031] The second detection camera S9 has an entrance port that is coaxial with the reflected light path of the second reflector S8. It is used to receive the scattered light that passes through the microsphere S6 and is processed by the second lens S7 and the second reflector S8, and to measure the position or displacement of the microsphere S6 on the XOY plane.

[0032] First detection camera S10: Located in the direction of the side-scattered light emission of microsphere S6, parallel to the ZOY plane, used to directly collect the side-scattered light of microsphere S6 and measure the position or displacement of microsphere S6 on the ZOY plane.

[0033] In this embodiment, the high-focusing first lens S5, microsphere S6, and second lens S7 are placed inside a container H1. The container H1 is a transparent and sealed optical container. The optical window of the container H1 is coaxially connected with the reflected light path of the first reflector S4 and the reflected light path of the second reflector S8 to ensure that the light path is unobstructed. The container H1 can be evacuated, filled with a specific gas, or filled with a transparent liquid to enable the device to be used in vacuum, gas, and liquid environments.

[0034] The measurement and control method based on this device includes the following steps: Step 1: Turn on the laser S1 to generate a first laser beam L1 with high collimation; the first laser beam L1 is incident on the first spatial light modulator S2. By adjusting the RF driver parameters of the first spatial light modulator S2, the first laser beam L1 is split into a second laser beam L2 and a third laser beam L3. The third laser beam L3 is completely absorbed by the first light block S11. At the same time, the intensity of the second laser beam L2 is modulated to adjust its light intensity to the initial light intensity that can achieve the suspension of the microsphere, thus generating a second laser beam L2 with controllable intensity.

[0035] Step 2: The second laser beam L2 generated in Step 1 is incident on the two-dimensional angle control system S3, and then sequentially deflected in the spatial orthogonal direction by the second spatial light modulator S13 and the third spatial light modulator S14. The second laser beam L2 is incident on the second spatial light modulator S13. By adjusting the parameters of its matching DR-DFA-MC driver, the second laser beam L2 is split into an eighth laser beam L8 and a ninth laser beam L9. The eighth laser beam L8 is absorbed by the third optical block S15, while the ninth laser beam L9 is deflected in the XOY plane, forming a deflection angle θ. XOY ; The deflected ninth laser beam L9 is incident on the third spatial light modulator S14. By adjusting the parameters of its matching DR-DFA-MC driver, the ninth laser beam L9 is split into a fourth laser beam L4 and a fifth laser beam L5. The fifth laser beam L5 is absorbed by the second optical block S12, while the fourth laser beam L4 is deflected in the ZOX plane, forming a deflection angle θ. ZOX ; Since the deflection directions of the second spatial light modulator S13 and the third spatial light modulator S14 are spatially orthogonal, by coordinating and adjusting the driver parameters of the two, the arbitrary pointing control of the fourth laser beam L4 in the ZOY plane can be achieved, thus generating a fourth laser beam L4 with adjustable pointing.

[0036] In step 3, the fourth laser beam L4 generated in step 2 is incident on the first reflecting mirror S4 at a 45° angle to the XOY plane. After being reflected by the first reflecting mirror S4, its pointing control changes from the ZOY plane to any pointing change within the XOY plane. The reflected fourth laser beam L4 is incident on the high-focusing first lens S5. After being highly focused by the high-focusing first lens S5, a vertically upward single-path optical trap is formed in the capture area inside the container H1. The focal position and light intensity of the optical trap are the initial preset values. The microsphere S6 is placed at the focal point of the optical trap. The optical trap force is balanced with the gravity of the microsphere and the environmental resistance in the gas / liquid environment, realizing the non-contact capture and stable suspension of the microsphere S6.

[0037] Step 4: Measure the position or displacement of the microsphere S6 on the ZOY plane and XOY plane respectively using the first detection camera S10 and the second detection camera S9 to obtain the three-dimensional position measurement data of the microsphere S6.

[0038] Step 5: Based on the three-dimensional position measurement data, by adjusting the intensity modulation parameters of the RF driver of the first spatial light modulator S2, the light intensity of the second laser beam L2 is changed, which in turn changes the light intensity of the fourth laser beam L4, ultimately changing the optical trap force distribution in the vertical Z-axis direction. When the intensity of the modulated light of the first spatial light modulator S2 is increased, the vertical light trap force of the light trap increases. The light trap force is greater than the resultant force of the microsphere's gravity and the environmental resistance. The microsphere S6 moves vertically upward in the positive Z-axis direction until it reaches a new force equilibrium position. When the intensity of the modulated light of the first spatial light modulator S2 is reduced, the vertical light trap force of the light trap decreases, and the resultant force of the gravity of the microsphere and the environmental resistance is greater than the light trap force. The microsphere S6 moves vertically downward in the negative Z-axis direction until a new force equilibrium position is reached. By continuously and precisely adjusting the light intensity of the first spatial light modulator S2, high-precision and continuous position control of the microsphere S6 in the Z-axis direction can be achieved.

[0039] Based on the three-dimensional position measurement data, the spatial deflection angle θ of the fourth laser beam L4 is changed by coordinating the driver parameters of the second spatial light modulator S13 and the third spatial light modulator S14 in the two-dimensional angle control system S3. XOY and θ ZOX After being reflected by the first reflecting mirror S4, the focal position of the light trap in the XOY plane is changed, thereby realizing two-dimensional positional manipulation of the microsphere S6 in the horizontal direction, such as... Figure 3 As shown, the specific implementation is as follows: Adjusting the driver parameters of the second spatial light modulator S13 changes the deflection angle θ. XOY The size and direction of the laser beam L4 are adjusted to achieve angular deflection of the fourth laser beam L4 in the X-axis direction within the XOY plane. The focus of the optical trap moves along the X-axis direction, causing the microsphere S6 to move synchronously along the X-axis. Adjusting the driver parameters of the third spatial light modulator S14 changes the deflection angle θ. ZOX The size and direction of the fourth laser beam L4 are adjusted to achieve angular deflection of the Y-axis direction in the XOY plane, and the focus of the optical trap moves along the Y-axis direction, which drives the microsphere S6 to move synchronously along the Y-axis. Due to θ XOY With θ ZOX To achieve spatial orthogonal deflection, the second spatial light modulator S13 and the third spatial light modulator S14 are coordinated and adjusted to change the intersection point of the fourth laser beam L4 with the XOY plane from the initial position P1 to any position P2 or P3 within the plane. The optical trap focus moves synchronously with the intersection point, ultimately enabling arbitrary two-dimensional position manipulation of the microsphere S6 within the XOY plane. Figure 4 As shown.

[0040] During the microsphere measurement and manipulation processes in steps 4 and 5, the first detection camera S10 and the second detection camera S9 are simultaneously activated to collect and fuse microsphere motion signals in real time, providing a basis for closed-loop control. Specifically: The first detection camera S10 collects the lateral scattered light from the microsphere S6 in real time. Through image recognition and displacement algorithm, it measures the position or displacement of the microsphere on the ZOY plane and obtains real-time position data of the Z-axis and Y-axis. The second detection camera S9 receives the scattered light that passes through the microsphere S6, converges at S7, and is reflected at S8 in real time. Using the same image recognition and displacement algorithm, it measures the position or displacement of the microsphere on the XOY plane and obtains real-time position data of the X and Y axes. The two-dimensional position data collected by the two detection cameras are transmitted to the data processing terminal. Through the data fusion algorithm, redundant data is eliminated and integrated to obtain the real-time position or displacement information (position, velocity, and acceleration of the X, Y, and Z axes) of the microsphere S6 in three-dimensional space. Based on this information, the first spatial light modulator S2 and / or the two-dimensional angle control system S3 are controlled in a closed-loop feedback manner to correct the three-dimensional position of the microsphere S6.

[0041] Furthermore, based on practical application requirements, the internal environment of container H1 is adjusted to enable three-dimensional measurement and manipulation of microspheres in vacuum, gas, and liquid environments. Specifically: Vacuum environment: The interior of container H1 is evacuated to a vacuum environment by a vacuum pumping system, eliminating the collision interference of gas molecules on the microspheres. It is suitable for scenarios such as vacuum optical trap sensing and basic physics research.

[0042] Gas environment: Fill the container H1 with a preset gas and adjust it to the required gas pressure. It is suitable for scenarios such as particle manipulation and gas sensing in gas environments.

[0043] Liquid environment: Fill the container H1 with a transparent liquid to ensure that the liquid is free of bubbles and impurities. It is suitable for scenarios such as biochemical detection, particle measurement and manipulation in liquid environments.

[0044] In all three environments, only the output power of the laser S1 and the intensity modulation parameters of the RF driver of the first spatial light modulator S2 need to be adjusted according to the environmental resistance. The remaining measurement and control steps are completely consistent, achieving seamless adaptation to multiple scenarios.

[0045] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A three-dimensional high-precision position measurement and manipulation method based on optically levitated microparticles, characterized in that, Includes the following steps: Step 1: A first laser beam (L1) is generated by a laser (S1), and the intensity of the first laser beam (L1) is modulated by a first spatial light modulator (S2) to generate a second laser beam (L2) with controllable intensity. Step 2: Input the second laser beam (L2) into the two-dimensional angle control system (S3), which includes a second spatial light modulator (S13) and a third spatial light modulator (S14); deflect the second laser beam (L2) in a first direction through the second spatial light modulator (S13) to generate a ninth laser beam (L9); then deflect the ninth laser beam (L9) in a second direction orthogonal to the first direction through the third spatial light modulator (S14) to generate a fourth laser beam (L4) with adjustable direction. Step 3: After the fourth laser beam (L4) is reflected by the first reflecting mirror (S4) and focused by the high-focusing first lens (S5), it forms a vertically upward optical trap in the capture area with adjustable focal position and light intensity to capture and suspend the microsphere (S6). Step 4: Measure the three-dimensional position of the microsphere (S6) using the first detection camera (S10) and the second detection camera (S9) to obtain measurement data; Step 5: Based on the measurement data, the optical trap force distribution in the vertical direction of the optical trap is changed by adjusting the first spatial light modulator (S2), thereby realizing the position control of the microsphere in the vertical direction; and / or the propagation direction of the fourth laser beam (L4) is changed by adjusting the two-dimensional angle control system (S3), so that the focal point of the optical trap formed by the high-focusing first lens (S5) moves in the XOY plane, thereby realizing the two-dimensional position control of the microsphere in the horizontal plane.

2. The method according to claim 1, characterized in that, Step 5 specifically includes: The second laser beam (L2) is received by the second spatial light modulator (S13) and divided into an eighth laser beam (L8) and a ninth laser beam (L9). The ninth laser beam (L9) is deflected at an angle in the XOY plane. The third spatial light modulator (S14) receives the ninth laser beam (L9) and divides it into a fourth laser beam (L4) and a fifth laser beam (L5), and deflects the fourth laser beam (L4) at an angle in the ZOX plane. The pointing control of the fourth laser beam (L4) in the ZOY plane is converted into pointing control in the XOY plane by the first reflector (S4), so that the intersection point of the fourth laser beam (L4) and the XOY plane can move arbitrarily in the plane.

3. The method according to claim 1, characterized in that, Also includes: The first detection camera (S10) continuously measures the position or displacement change of the microsphere (S6) on the ZOY plane, and the second detection camera (S9) continuously measures the position or displacement change of the microsphere (S6) on the XOY plane. Combining the measurement results of the first detection camera (S10) and the second detection camera (S9), the real-time position or displacement information of the microsphere (S6) in three-dimensional space is obtained. Based on the real-time position or displacement information, the first spatial light modulator (S2) and / or the two-dimensional angle control system (S3) are subjected to closed-loop feedback control to correct the three-dimensional position of the microsphere (S6).

4. The method according to claim 1, characterized in that, The method is applied to the three-dimensional position measurement and manipulation of the microsphere (S6) in a vacuum environment, liquid environment or gas environment.

5. An apparatus for implementing the method according to any one of claims 1-4, characterized in that, include: Laser (S1) is used to emit the first laser beam (L1). A first spatial light modulator (S2) is used to receive the first laser beam (L1) and split it into a second laser beam (L2) and a third laser beam (L3), and to adjust the intensity of the second laser beam (L2). A two-dimensional angle control system (S3) is used to receive the intensity-modulated second laser beam (L2) and convert it into a fourth laser beam (L4) with two-dimensional pointing control in the ZOY plane. The first reflector (S4) is used to switch the pointing control of the fourth laser beam (L4) from the ZOY plane to the XOY plane; A high-focusing first lens (S5) is used to receive the fourth laser beam (L4) reflected by the first reflector (S4) and form a vertically upward optical trap for capturing the microsphere (S6). The first detection camera (S10) is used to collect the scattered light of the microsphere (S6) to measure its position or displacement on the ZOY plane; The second detection camera (S9) is used to receive the scattered light after passing through the microsphere (S6) to measure its position or displacement on the XOY plane.

6. The apparatus according to claim 5, characterized in that, The two-dimensional angle control system (S3) includes: The second spatial light modulator (S13) is used to receive the second laser beam (L2), divide it into an eighth laser beam (L8) and a ninth laser beam (L9), and deflect the ninth laser beam (L9) at an angle in the XOY plane. The third spatial light modulator (S14) is used to receive the ninth laser beam (L9), divide it into a fourth laser beam (L4) and a fifth laser beam (L5), and deflect the fourth laser beam (L4) at an angle in the ZOX plane. The output beam control directions of the second spatial light modulator (S13) and the third spatial light modulator (S14) are orthogonal.

7. The apparatus according to claim 6, characterized in that, The first reflector (S4) is set at a 45-degree spatial angle with the XOY plane, and is used to convert the arbitrary pointing control of the fourth laser beam (L4) in the ZOY plane into arbitrary pointing change in the XOY plane.

8. The apparatus according to claim 6, characterized in that, It also includes a first light block (S11), a second light block (S12), and a third light block (S15). The first light barrier (S11) is used to absorb the third laser beam (L3). The second light barrier (S12) is used to absorb the fifth laser beam (L5); The third light barrier (S15) is used to absorb the eighth laser beam (L8).

9. The apparatus according to claim 5, characterized in that, It also includes a second lens (S7) and a second reflecting mirror (S8); The second lens (S7) is disposed between the microsphere (S6) and the second reflector (S8) to converge the scattered light; The second reflector (S8) is used to reflect the scattered light that has passed through the second lens (S7) to the second detection camera (S9).

10. The apparatus according to claim 5, characterized in that, It also includes a container (H1), in which the high-focusing first lens (S5), microsphere (S6) and second lens (S7) are placed, and the interior of the container (H1) is a vacuum environment, a gas environment or a liquid environment.

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