Photoelectric tweezers device capable of controlling microscopic particles in patterning mode

Abstract

The invention discloses a photoelectric tweezer device capable of patterned control of microscopic particles, and relates to the technical field of microscopic particle control, the photoelectric tweezer device comprises a patterned light beam generation light path, an ultraviolet sheet illumination module and a photovoltaic wafer control platform, the patterned light beam generation light path generates preset pattern light beams, and the patterned light beam generation light path generates the preset pattern light beams; the preset pattern light beam generates a first electric field on the photovoltaic wafer control platform; the ultraviolet sheet-shaped illumination module generates second laser, the second laser is subjected to beam expansion, meanwhile, the intensity and the diameter of the second laser after beam expansion are controlled, and a second electric field is generated on the photovoltaic wafer control platform; microscopic particles in the photovoltaic wafer control platform move towards the preset pattern area under the influence of the first electric field and the second electric field. The microscopic particles are captured by using the patterned laser, so that the number of the manipulated particles is increased, and the capturing efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of microscopic particle manipulation, and more particularly to a photoelectric tweezers device capable of patterning and manipulating microscopic particles. Background Art

[0002] Optoelectronic tweezers (OET) are a new technology that can flexibly manipulate a large number of tiny objects through dielectrophoretic force. The manipulated objects can be suspended particles, biological cells, macromolecular particles, and even tiny particles such as atoms. Since lithium niobate crystals (LiNbO3, LN) have good optoelectronic properties and can generate a photovoltaic electric field on their surface after illumination, particle capture can be achieved without external electrodes. Optoelectronic tweezers have greatly enriched the means of light-induced micromanipulation and are mainly used for analysis, screening, reaction, extraction, detection, etc. OET based on lithium niobate has now become the core technology of chip laboratories.

[0003] In the past 20 years, people have been committed to conducting in-depth research and continuous innovation on the function of photoelectric tweezers. Esseling M et al. have successively reported the capture experiment of OET on the surface of C-cut LiNbO3, using spatial electric field to capture polystyrene microspheres with silver uniformly attached on the surface. Munoz-Martinez JF et al. first realized the capture of micron-sized calcium carbonate particles and nano-sized aluminum particles on C-cut LiNbO3 crystals, forming one-dimensional and two-dimensional capture patterns respectively. Verma RS et al. used OET as a means to manipulate polystyrene microspheres and red blood cells. In recent years, there has been an increasing trend in the research reports on OET in China. Wang Kai et al. from Tianjin University used self-built femtosecond laser optical tweezers to achieve stable capture of human red blood cells (RBC). Song Chunfeng, Ni Zhonghua et al. designed a micromanipulation chip based on light-induced dielectrophoresis technology combined with a detection and tracking system to construct a manipulation experimental platform based on the comprehensive analysis of current biological particle micromanipulation technology, and completed the capture and transportation of particles, including the transportation of single particles.

[0004] By utilizing the photovoltaic effect of crystals (lithium niobate, lithium tantalate), there is no need for external electrodes, the required light intensity is low, and a large number of microscopic particles can be flexibly captured, which improves the capture efficiency and reduces the capture time. However, the OET coverage based on a single laser point is small, the number of manipulated particles is limited, and the capture efficiency is low. The development of parallel OET technology has important practical significance for high-throughput microscopic particle manipulation.

[0005] Therefore, how to increase the number of manipulated particles while improving capture efficiency is an urgent problem that technicians in this field need to solve. Summary of the invention

[0006] In view of this, the present invention provides a photoelectric tweezers device capable of patterning and manipulating microscopic particles to solve the problems existing in the above-mentioned background technology.

[0007] In order to achieve the above object, the present invention adopts the following technical solution:

[0008] A photoelectric tweezer device capable of patterned manipulation of microscopic particles comprises: a patterned light beam generating optical path, an ultraviolet sheet lighting module and a photovoltaic chip manipulation platform, wherein the patterned light beam generating optical path generates a preset pattern light beam, and the preset pattern light beam generates a first electric field on the photovoltaic chip manipulation platform; the ultraviolet sheet lighting module generates a second laser, and then expands the second laser, while controlling the intensity and diameter of the expanded second laser, to generate a second electric field on the photovoltaic chip manipulation platform; the microscopic particles inside the photovoltaic chip manipulation platform move toward a preset pattern area under the influence of the first electric field and the second electric field.

[0009] Preferably, the photovoltaic chip manipulation platform includes: a clamping displacement stage, a first C-cut iron-doped lithium niobate wafer and a second C-cut iron-doped lithium niobate wafer, the first C-cut iron-doped lithium niobate wafer and the second C-cut iron-doped lithium niobate wafer are fixed on the clamping displacement stage; the first C-cut iron-doped lithium niobate wafer receives a preset pattern light beam to generate a first electric field; the second C-cut iron-doped lithium niobate wafer receives a second laser to generate a second electric field.

[0010] Preferably, the patterned light beam generating optical path includes: a first laser, a first lens, a second lens, a half-wave plate, a spatial light modulator, a first quarter-wave plate, a polarizer, a second quarter-wave plate, an imaging lens, a dichroic mirror, a microscope objective, an illumination light source, a filter and an imaging camera; the first laser generates a first laser, which sequentially passes through the first lens, the second lens, the half-wave plate, the spatial light modulator, the first quarter-wave plate, the polarizer, the second quarter-wave plate and the imaging lens to generate a preset pattern light beam; the preset pattern light beam passes through the dichroic mirror and the microscope objective lens and enters the first C-cut iron-doped lithium niobate wafer; the illumination light source provides light for the photovoltaic wafer manipulation platform and the microscope objective lens, the imaging camera records the movement of microscopic particles in the photovoltaic wafer manipulation platform, and the filter adjusts the brightness of the light entering the imaging camera.

[0011] Preferably, the ultraviolet sheet lighting module includes: a second laser, a beam expansion system and an adjustable slit, the second laser generates a second laser, which passes through the beam expansion system and the adjustable slit in sequence; the beam expansion system expands the diameter of the second laser to twice the original diameter; the adjustable slit controls the beam diameter and intensity of the second laser after the expanded diameter by adjusting the slit, and then inputs the second laser beam into the second C-cut iron-doped lithium niobate wafer.

[0012] Preferably, the beam expansion system comprises a third lens and a fourth lens, the focal length of the third lens is 30 mm, the focal length of the fourth lens is 60 mm, and the distance between the third lens and the fourth lens is 90 mm.

[0013] Preferably, the half-wave plate adjusts the polarization direction of the laser incident on the spatial light modulator to form an angle of 45° / 135° with the working direction of the spatial light modulator.

[0014] Preferably, the first quarter wave plate converts the depolarized light reflected by the spatial light modulator into a linear depolarization state, sharpening the spot pattern passing through the polarizer.

[0015] Preferably, the pattern area loaded on the spatial light modulator is consistent with the preset pattern on the focal plane of the microscope objective, the phase information loaded in the pattern area is π, and the phase information of other areas is 0. The phase delay of π is used to make the polarization state of the laser reflected by the loaded pattern area orthogonal to the polarization state of the incident laser.

[0016] Preferably, a second quarter wave plate is arranged after the polarizer, which is 45 degrees to the polarization direction of the light passing through the polarizer, so as to convert the linear polarization into circular polarization.

[0017] Preferably, the dichroic mirror forms an angle of 45° with the incident laser, totally reflects the incident laser wavelength band, and highly transmits the illumination light source wavelength band.

[0018] It can be seen from the above technical solutions that, compared with the prior art, the present invention discloses a photoelectric tweezers device capable of patterning and manipulating microscopic particles, which has the following advantages compared with the prior art:

[0019] 1. The use of patterned lasers to capture microscopic particles is highly efficient. The efficiency is reflected in the fact that the structure of the patterned beam provides a larger beam irradiation range, which can capture particles with higher flux;

[0020] 2. It has more diverse micro-particle manipulation forms. The spatial light modulator can be used to shape the beam, so that the laser beam becomes a pattern of various shapes to manipulate the micro-particles;

[0021] 3. It has a more flexible control method, which can capture microscopic particles in liquid environment as well as microscopic particles in air environment;

[0022] 4. The device is easy to operate, scientifically designed, low-cost, and easy to promote and apply. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0024] Figure 1 A schematic diagram of the structure of an optoelectronic tweezers device capable of patterned manipulation of microscopic particles provided by the present invention;

[0025] Figure 2 A characteristic diagram of the light beam at each mark on the light path of an optoelectronic tweezers device capable of patterned manipulation of microscopic particles provided by the present invention;

[0026] Figure 3 A diagram showing the principle and process of photovoltaic effect manipulation of microparticles in a photoelectric tweezers device capable of patterned manipulation of microparticles provided by the present invention; wherein a is a diagram showing the principle of photovoltaic effect manipulation of microparticles, b is a diagram showing the distribution of microparticles before laser irradiation, c is a diagram showing the movement trend of microparticles after laser irradiation, and d is a diagram showing the final distribution of microparticles after laser irradiation;

[0027] In the figure: 1 patterned light beam generating optical path; 101 first laser; 102 first lens; 103 second lens; 104 half-wave plate; 105 spatial light modulator; 106 first quarter-wave plate; 107 polarizer; 108 second quarter-wave plate; 109 imaging lens; 110 dichroic mirror; 111 microscope objective; 112 illumination light source; 113 filter; 114 image sensor; 2 ultraviolet sheet illumination module; 201 second laser; 202 third lens; 203 fourth lens; 204 adjustable slit; 3 photovoltaic wafer manipulation platform; 301 clamping displacement stage; 302 first C-cut iron-doped lithium niobate wafer; 303 second C-cut iron-doped lithium niobate wafer. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only 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.

[0029] The embodiment of the present invention discloses a photoelectric tweezers device capable of patterning and manipulating microscopic particles, such as Figure 1As shown, it includes: a patterned beam generating optical path 1, an ultraviolet sheet lighting module 2 and a photovoltaic chip manipulation platform 3, the patterned beam generating optical path 1 generates a preset pattern beam, and the preset pattern beam generates a first electric field on the photovoltaic chip manipulation platform 3; the ultraviolet sheet lighting module 2 generates a second laser, and then expands the second laser, while controlling the intensity and diameter of the second laser after expansion, to generate a second electric field on the photovoltaic chip manipulation platform 3; the microscopic particles inside the photovoltaic chip manipulation platform 3 move toward the preset pattern area under the influence of the first electric field and the second electric field.

[0030] In a specific embodiment, the photovoltaic chip manipulation platform 3 includes a clamping displacement stage 301, a first C-cut iron-doped lithium niobate wafer 302 and a second C-cut iron-doped lithium niobate wafer 303, and the first C-cut iron-doped lithium niobate wafer 302 and the second C-cut iron-doped lithium niobate wafer 303 are fixed on the clamping displacement stage 301; the first C-cut iron-doped lithium niobate wafer 302 receives a preset pattern light beam to generate a first electric field; the second C-cut iron-doped lithium niobate wafer 303 receives a second laser to generate a second electric field; the clamping displacement stage 301 can adjust the relative positions of the first C-cut iron-doped lithium niobate wafer 302 and the second C-cut iron-doped lithium niobate wafer 303 in the x-, y-, and z-axis directions.

[0031] In a specific embodiment, the patterned light beam generating optical path 1 includes: a first laser 101, a first lens 102, a second lens 103, a half-wave plate 104, a spatial light modulator 105, a first quarter-wave plate 106, a polarizer 107, a second quarter-wave plate 108, an imaging lens 109, a dichroic mirror 110, a microscope objective lens 111, an illumination light source 112, a filter 113 and an imaging camera 114. The first laser 101 generates a first laser, which passes through the first lens 102, the second lens 103, the half-wave plate 104, the spatial light modulator 105, the first quarter-wave plate 106, the polarizer 107, the second quarter-wave plate 108, the imaging lens 109, the dichroic mirror 110, the microscope objective lens 111, the illumination light source 112, the filter 113 and the imaging camera 114 in sequence. After entering the spatial light modulator 105 along an angle of 5-10°, the first quarter wave plate 106, the polarizer 107, the second quarter wave plate 108 and the imaging lens 109 placed in sequence on the reflected light path generate a preset pattern light beam; the preset pattern light beam passes through the dichroic mirror 110 and the microscope objective lens 111 and enters the first C-cut iron-doped lithium niobate wafer 302; the illumination light source 112 provides light for the photovoltaic wafer manipulation platform 3 and the microscope objective lens 111, the imaging camera 114 records the movement of microscopic particles in the photovoltaic wafer manipulation platform 3, and the filter 113 adjusts the brightness of the light entering the imaging camera 114.

[0032] Among them, mark 1 is a diagram of the polarization direction of the laser after laser beam expansion, mark 2 is a diagram of the polarization direction of the laser after passing through a half-wave plate, mark 3 is a diagram of the loading pattern of the spatial light modulator, mark 4 is a diagram of the depolarized light reflected by the spatial light modulator, mark 5 is a diagram of the depolarization of the first quarter-wave plate converted into a linear polarization state, mark 6 is a diagram of the polarization direction of the laser passing through a polarizer, and mark 7 is a diagram of the second quarter-wave plate converting linear polarization into circular polarization.

[0033] Reference Figure 2In this embodiment, the continuous wave excitation light is provided by an external light source and is all linearly polarized light (as shown by mark 1). The central band of the first laser 101 used is 405 nm; the focal length f1 of the first lens 102 is 30 mm, the focal length f2 of the second lens 103 is 90 mm, the first lens 102 and the second lens 103 are 120 mm apart (two convex lenses form a beam expansion system), and the laser is expanded to three times its original diameter through the beam expansion system composed of the first lens 102 and the second lens 103; after beam expansion, the laser is adjusted to a 45° angle with the working direction of the spatial light modulator through a half-wave plate 104. (As shown by mark 2). The pattern area loaded on the spatial light modulator 105 is consistent with the expected pattern on the focal plane of the microscope objective 111, and the phase information loaded on the pattern area is π, and the phase information of other areas is 0. The delay of the π phase makes the polarization state of the laser reflected by the loaded pattern area orthogonal to the polarization state of the incident laser (as shown by mark 3); the laser reflected by the spatial light modulator 105 enters the first quarter wave plate 106 to convert the depolarized light reflected by the spatial light modulator 105 (as shown by mark 4) into a linear depolarization state (as shown by mark 5) to sharpen the spot pattern passing through the polarizer 107, and then the light beam enters the polarizer 107. The light passing direction of the polarizer 107 is 135° / -45°, which is parallel to the polarization state of the laser after being modulated by π by the spatial light modulator 105, so that the vibration direction of the polarized light is incident at 135° / -45° (as shown by mark 6), then the linear polarized light is converted into circular polarized light (as shown in mark 7) by a second quarter wave plate 108 which is 45 degrees to the polarization direction of the polarizer 107, and then passes through the imaging lens 109 and is reflected by the dichroic mirror 110 which is 45 degrees to the incident laser, and enters the microscope objective 111, and forms an image on the upper surface of the first C-cut iron-doped lithium niobate wafer 302. The illumination light source 112 provides light source for the imaging camera 114, and the microscopic particle movement information of the photovoltaic wafer manipulation platform 3 is transmitted to the imaging camera 114 through the microscope objective 111, the dichroic mirror 110, and the filter 113; an imaging lens 109 is arranged between the spatial light modulator 105 and the microscope objective 111, and the focal length f5 of the imaging lens 109 is 150 mm, and the distances from the imaging lens 109 to the spatial light modulator 105 and to the rear focal plane of the microscope objective 111 are equal to the focal length of the imaging lens 109, that is, f5=L1+L2;

[0034] In a specific embodiment, the ultraviolet sheet lighting module 2 includes: a second laser 201, a beam expansion system and an adjustable slit 204. The second laser 201 generates a second laser, which passes through the beam expansion system and the adjustable slit 204 in sequence; the beam expansion system expands the diameter of the second laser to twice the original diameter; the adjustable slit 204 controls the beam diameter and intensity of the second laser after the diameter is expanded by adjusting the slit, and then inputs the second laser beam into the second C-cut iron-doped lithium niobate wafer 303; the height of the center position of the adjustable slit 204 is consistent with the center position of the beam of the second laser 201; and the center position of the adjustable slit 204 and the center position of the beam of the second laser 201 are always consistent with the center position of the second C-cut lithium niobate wafer 303 on the photovoltaic wafer manipulation platform 3.

[0035] In a specific embodiment, the second laser 201 has the same central wavelength of 405 nm as the first laser 101; the focal length f3 of the third lens 202 is 30 mm, the focal length f4 of the fourth lens 203 is 60 mm, the third lens 202 and the fourth lens 203 are 90 mm apart (two convex lenses form a beam expansion system), and the laser is expanded to twice its original diameter through the beam expansion system composed of the third lens 202 and the fourth lens 203; after beam expansion, the laser can control the beam diameter and intensity of the second C-cut iron-doped lithium niobate wafer 303 from the side through the adjustable slit 204.

[0036] In a specific embodiment, the beam expansion system includes a third lens 202 and a fourth lens 203 , the focal length of the third lens 202 is 30 mm, the focal length of the fourth lens 203 is 60 mm, and the distance between the third lens 202 and the fourth lens 203 is 90 mm.

[0037] In a specific embodiment, the half-wave plate 104 adjusts the polarization direction of the laser light incident on the spatial light modulator 105 to form an angle of 45° / 135° with the working direction of the spatial light modulator 105 .

[0038] In a specific embodiment, the first quarter wave plate 106 converts the depolarized light reflected by the spatial light modulator 105 into a linear polarization state, and sharpens the spot pattern passing through the polarizer 107 .

[0039] In a specific embodiment, the pattern area loaded on the spatial light modulator 105 is consistent with the preset pattern on the focal plane of the microscope objective 111, the phase information loaded in the pattern area is π, and the phase information of other areas is 0. The phase delay of π is used to make the polarization state of the laser reflected by the loaded pattern area orthogonal to the polarization state of the incident laser.

[0040] In a specific embodiment, a second quarter wave plate 108 is disposed after the polarizer 107 , which is 45° away from the polarization direction of the light passing through the polarizer 107 , so as to convert the linear polarization into circular polarization.

[0041] In a specific embodiment, the dichroic mirror 110 forms an angle of 45° with the incident laser, fully reflects the incident laser wavelength band, and highly transmits the illumination light source 112 wavelength band.

[0042] Reference Figure 3 In this embodiment, the first C-cut iron-doped lithium niobate wafer 302 and the second C-cut iron-doped lithium niobate wafer 303 have an iron doping concentration of 0.03%, and the +C plane direction is consistent. The second C-cut iron-doped lithium niobate wafer 303 will generate a large-scale electric field after being irradiated by the second laser 201, and the patterned area irradiated by the first laser 101 will generate a small-scale electric field on the first C-cut iron-doped lithium niobate wafer 302 after being reduced by the microscope lens. Since the charged areas on the two wafers are of different sizes, an inhomogeneous electric field will be formed between the wafers (as shown in a), and the microscopic particles are therefore in a non-equilibrium force state and move toward the patterned area (as shown in b, c, and d). The electric field force to which the microscopic particles are subjected after being polarized in the inhomogeneous electric field is the dielectrophoretic force. This is a conventional means of manipulating microscopic particles by photoelectric tweezers. The expression of the dielectrophoretic force to which microscopic particles are subjected in the inhomogeneous electric field is:

[0043]

[0044] Among them, r is the radius of the microscopic particle, ε m is the dielectric constant of the medium, E is the electric field strength, α ( ω is the Klausius-Mossotti factor;

[0045] α ( ω ) The expression is:

[0046]

[0047] in, Represent the complex dielectric constants of microscopic particles and media, σ is the conductivity, and ω is the angular frequency of the electric field. When the electric field is constant, that is, when the angular frequency of the electric field ω→0, ε * The imaginary part of approaches infinity, and the expression of Re[α(ω)] can be expressed as:

[0048]

[0049] Therefore, the final dielectrophoretic force expression is:

[0050]

[0051] In this embodiment, the direction and magnitude of the dielectrophoretic force exerted on the microscopic particles can be determined according to the above formula; when Re[α(ω)]>0, the microscopic particles are captured by the photoelectric tweezers and are subjected to a positive dielectrophoretic force; when Re[α(ω)]<0, the microscopic particles are captured by the photoelectric tweezers and are subjected to a negative dielectrophoretic force.

[0052] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0053] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An optoelectronic tweezers device capable of patterning and manipulating microscopic particles, characterized in that: include: A patterned light beam generating optical path (1), an ultraviolet sheet lighting module (2) and a photovoltaic chip manipulation platform (3), wherein the patterned light beam generating optical path (1) generates a preset pattern light beam, and the preset pattern light beam generates a first electric field on the photovoltaic chip manipulation platform (3); the ultraviolet sheet lighting module (2) generates a second laser, and then expands the second laser, while controlling the intensity and diameter of the expanded second laser, to generate a second electric field on the photovoltaic chip manipulation platform (3); microscopic particles inside the photovoltaic chip manipulation platform (3) move toward a preset pattern area under the influence of the first electric field and the second electric field.

2. The photoelectric tweezers device capable of patterning and manipulating microscopic particles according to claim 1, characterized in that: The photovoltaic wafer manipulation platform (3) comprises: a clamping displacement platform (301), a first C-cut iron-doped lithium niobate wafer (302) and a second C-cut iron-doped lithium niobate wafer (303); the first C-cut iron-doped lithium niobate wafer (302) and the second C-cut iron-doped lithium niobate wafer (303) are fixed on the clamping displacement platform (301); the first C-cut iron-doped lithium niobate wafer (302) receives a preset pattern light beam to generate a first electric field; the second C-cut iron-doped lithium niobate wafer (303) receives a second laser to generate a second electric field.

3. The photoelectric tweezers device capable of patterning and manipulating microscopic particles according to claim 2, characterized in that: The patterned light beam generating optical path (1) comprises: a first laser (101), a first lens (102), a second lens (103), a half-wave plate (104), a spatial light modulator (105), a first quarter-wave plate (106), a polarizer (107), a second quarter-wave plate (108), an imaging lens (109), a dichroic mirror (110), a microscope objective lens (111), an illumination light source (112), a filter (113) and an imaging camera (114). The first laser (101) generates a first laser, which passes through the first lens (102), the second lens (103), the half-wave plate (104), the spatial light modulator (105), the first quarter-wave plate (106), the polarizer (107), the second quarter-wave plate (108), the imaging lens (109), the dichroic mirror (110), the microscope objective lens (111), the illumination light source (112), the filter (113) and the imaging camera (114). The light modulator (105), the first quarter wave plate (106), the polarizer (107), the second quarter wave plate (108) and the imaging lens (109) generate a preset pattern light beam; the preset pattern light beam passes through a dichroic mirror (110) and a microscope objective lens (111) and enters the first C-cut iron-doped lithium niobate wafer (302); the illumination light source (112) provides light for the photovoltaic wafer manipulation platform (3) and the microscope objective lens (111); the imaging camera (114) records the movement of microscopic particles in the photovoltaic wafer manipulation platform (3); and the filter (113) adjusts the brightness of the light entering the imaging camera (114).

4. The photoelectric tweezers device capable of patterning and manipulating microscopic particles according to claim 2, characterized in that: The ultraviolet sheet lighting module (2) comprises: a second laser (201), a beam expansion system and an adjustable slit (204); the second laser (201) generates a second laser which passes through the beam expansion system and the adjustable slit (204) in sequence; the beam expansion system expands the diameter of the second laser to twice its original diameter; the adjustable slit (204) controls the beam diameter and intensity of the second laser after the diameter is expanded by adjusting the slit, and then inputs the second laser beam into the second C-cut iron-doped lithium niobate wafer (303).

5. The photoelectric tweezers device capable of patterning and manipulating microscopic particles according to claim 4, characterized in that: The beam expansion system comprises a third lens (202) and a fourth lens (203); the focal length of the third lens (202) is 30 mm, the focal length of the fourth lens (203) is 60 mm, and the third lens (202) and the fourth lens (203) are 90 mm apart.

6. The photoelectric tweezers device capable of patterning and manipulating microscopic particles according to claim 3, characterized in that: The half-wave plate (104) adjusts the polarization direction of the laser light incident on the spatial light modulator (105) to form an angle of 45° / 135° with the working direction of the spatial light modulator (105).

7. The photoelectric tweezers device capable of patterning and manipulating microscopic particles according to claim 3, characterized in that: The first quarter wave plate (106) converts the depolarized light reflected by the spatial light modulator (105) into a linear depolarization state, and sharpens the light spot pattern passing through the polarizer (107).

8. The photoelectric tweezers device capable of patterning and manipulating microscopic particles according to claim 3, characterized in that: The pattern area loaded on the spatial light modulator (105) is consistent with a preset pattern on the focal plane of the microscope objective lens (111), the phase information loaded in the pattern area is π, and the phase information of other areas is 0, and the polarization state of the laser reflected by the loaded pattern area is orthogonal to the polarization state of the incident laser by utilizing the delay of the π phase.

9. The photoelectric tweezers device capable of patterning and manipulating microscopic particles according to claim 3, characterized in that: A second quarter wave plate (108) is arranged behind the polarizer (107), which is 45 degrees to the polarization direction of the light passing through the polarizer (107) and converts linear polarization into circular polarization.

10. The photoelectric tweezers device capable of patterning and manipulating microscopic particles according to claim 3, characterized in that: The dichroic mirror (110) forms an angle of 45° with the incident laser, fully reflects the incident laser wavelength band, and highly transmits the illumination light source (112) wavelength band.

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