CN114299802A - Optical tweezers experiment teaching and scientific research device based on liquid crystal device - Google Patents

Abstract

The invention relates to an optical tweezers device based on a liquid crystal device for experimental teaching and scientific research, which comprises an optical component support frame, and a light source module, a beam expanding module, a polarization control module, a wavefront modulation module, a beam shrinking module, a focusing module, a sample adjusting module, a microscopic module and a monitoring and recording module which are arranged on the optical component support frame; the wave front modulation module comprises a second adjustable diaphragm (501), a patterned orientation liquid crystal wave plate (502) and a liquid crystal wave plate adjusting frame (503), wherein the second adjustable diaphragm (501) and the liquid crystal wave plate adjusting frame (503) are movably arranged on an optical component support frame, the patterned orientation liquid crystal wave plate (502) is arranged on the liquid crystal wave plate adjusting frame (503), and the patterned orientation liquid crystal wave plate (502) has patterned orientation. Compared with the prior art, the invention meets the requirements of optical tweezers experiment teaching and scientific research, and has strong operability, strong intuition and compact structure.

Description

Optical tweezers experiment teaching and scientific research device based on liquid crystal device

Technical Field

The invention relates to the technical field of optics, in particular to an optical tweezers device based on a liquid crystal device for experiment teaching and scientific research.

Background

Optical tweezers, also known as single-beam gradient force optical traps, are tangible objects that are routinely used to hold objects, and the objects are clamped by the tweezers applying a certain force. The optical tweezers for capturing the tiny particles is a special optical field, when the optical field interacts with an object, the whole object is subjected to the action of light so as to achieve the effect of being clamped, and then the purpose of moving the object can be achieved by moving light beams. If a square circle of a few microns is defined by the center of the formed light field, it will be observed that once photons hit the forbidden region, they will automatically and rapidly fall off the center of the light, indicating that the light field has the effect of gravity. If the particles to be captured by the optical tweezers are more than the glass beads falling into the bottom of the bowl, the optical tweezers look like a trap. The special optical field creates a region with lower potential energy, namely a potential barrier exists from the inside to the outside of the region, when the kinetic energy of an object is not enough to overcome the potential barrier, particles always stay in the trap, and finally the effect that the object under the action of the optical tweezers runs along a specific route is presented. In addition, when the light beam passes through the liquid crystal wave plate with the topological charge number and then is focused, the micro particles can generate specific motion around the axis due to the vortex light beam carrying orbital angular momentum under the action of the geometric phase of the liquid crystal wave plate.

The existing commercial optical tweezers are compact in structural design for safety and portability, and are packaged through a protective shell, so that students cannot know the working principle of the commercial optical tweezers conveniently, the intuition performance is poor, most parts of the optical tweezers are designed and formed, and the operability is poor.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide an optical tweezers device based on a liquid crystal device for experimental teaching and scientific research.

The purpose of the invention can be realized by the following technical scheme:

an optical tweezers device based on a liquid crystal device for experimental teaching and scientific research comprises an optical component support frame, and a light source module, a beam expanding module, a polarization control module, a wavefront modulation module, a beam shrinking module, a focusing module, a sample adjusting module, a microscopic module and a monitoring and recording module which are arranged on the optical component support frame;

the wave-front modulation module comprises a second adjustable diaphragm, a patterned oriented liquid crystal wave plate and a liquid crystal wave plate adjusting frame, wherein the second adjustable diaphragm and the liquid crystal wave plate adjusting frame are movably arranged on the optical component supporting frame, and the patterned oriented liquid crystal wave plate is arranged on the liquid crystal wave plate adjusting frame.

Furthermore, the optical component support frame comprises an optical bread board and vertical supports, the vertical supports are vertically arranged on the optical bread board, a plurality of sliding bases are movably arranged on the vertical supports along the normal direction of the optical bread board, each sliding base comprises an installation sliding block, a supporting rod sleeve and a supporting rod, the installation sliding blocks are movably arranged on the vertical supports, the supporting rod sleeves are vertically fixed on the installation sliding blocks, and the supporting rods are coaxially inserted into the supporting rod sleeves.

Furthermore, the optical component support frame further comprises two reflectors, each reflector is fixed on one of the sliding bases through a reflector frame, the two reflectors are symmetrically arranged relative to the vertical support, the light source module, the beam expanding module, the polarization control module and one of the reflectors are located on the same side of the vertical support, and the wavefront modulation module, the beam contracting module, the focusing module, the sample adjusting module, the microscopic module, the monitoring and recording module and the other reflector are located on the same side of the vertical support.

Further, the light source module comprises a solid laser, a first adjustable diaphragm and an adjustable optical attenuator which are movably arranged on the optical component support frame in sequence.

Furthermore, the polarization control module comprises signal voltage output equipment, and a linear polarizer, an electric control liquid crystal wave plate and a quarter wave plate which are movably arranged on the optical component support frame, wherein the signal voltage output equipment is arranged on the optical component support frame and is electrically connected with the electric control liquid crystal wave plate, the number of the electric control liquid crystal wave plates is one or more, and the number of the quarter wave plates is one or more.

Furthermore, the beam expanding module comprises two first lens groups with different focal lengths, and the beam expanding module is movably arranged on the optical component support frame;

the beam-reducing module comprises two second lens groups with different focal lengths, and is movably arranged on the optical component support frame.

Further, the focusing module comprises a right-angle optical adjusting frame, a first beam splitter, a first objective lens and an objective lens fine-tuning frame, wherein the right-angle optical adjusting frame and the objective lens fine-tuning frame are movably arranged on the optical component support frame, the first beam splitter is arranged on the right-angle optical adjusting frame, and the first objective lens is arranged on the objective lens fine-tuning frame.

Further, the sample adjustment module include sample holding frame, triaxial fine setting platform and particle sample, triaxial fine setting platform activity set up on the optical component support frame, the sample holding frame locate on the triaxial fine setting platform, the particle sample locate on the sample holding frame.

Furthermore, the microscope module comprises a second objective lens, an ocular lens, an illumination device, a stand column, a microscope adjusting frame, a microscope straight cylinder and a color filter, wherein the stand column is arranged on the optical component support frame, the microscope adjusting frame is movably arranged on the stand column, the microscope straight cylinder is arranged on the microscope adjusting frame, one end of the microscope straight cylinder is connected with the second objective lens, the other end of the microscope straight cylinder is connected with the ocular lens, the color filter is arranged on the second objective lens, and the illumination device is arranged on the microscope straight cylinder.

Furthermore, the monitoring and recording module comprises a first monitoring camera, a protection sheet, a computer and a second monitoring camera, wherein the first monitoring camera and the second monitoring camera are respectively electrically connected with the computer, the first monitoring camera is arranged on the focusing module, the protection sheet is arranged on the first monitoring camera, and the second monitoring camera is arranged on the microscope module.

Compared with the prior art, the invention has the following beneficial effects:

(1) the invention is characterized in that a sample adjusting module is used for placing a sample, a light source module generates light beams, a beam expanding module amplifies the light beams, a polarization control module generates light beams with various polarization states, a wavefront modulation module realizes the modulation of the wavefront of the light beams by utilizing the principle of liquid crystal geometric phase, a beam contracting module reduces the light beams, a focusing module is used for focusing the light beams carrying specific phases on the sample and is used for amplifying particle samples, a monitoring and recording module monitors and records the specific motion of particles of the sample in real time, a wavefront modulation module carries out wavefront modulation on the light beams by utilizing a patterned oriented liquid crystal wave plate with patterned orientation to enable the light beams to carry the geometric phase, then the particles are captured after the light beams are focused, and the specific motion of the particles is realized under the driving of the beam geometric phase, the method completely meets the requirements of optical tweezers experiment teaching and scientific research, and has strong operability and compact structure, the efficiency is high, the structure of the optical tweezers device is simple, and the cost is low;

(2) the optical tweezers device has intuitive optical design, is easy for students to understand the working principle, is convenient for the students to operate the operation space of the manual experiment, is suitable for the students of different age levels, has very obvious advantages on exciting the physical learning interest of the students, cultivating the exploration spirit of the students and promoting the scientific literacy of the students, gives attention to the cultivation and the excitation of the interest of the students while considering the scientific research applicability, practically brings the zero distance of the science and technology frontier of the current world to the students, and improves the experimental manual ability of the students while expanding the eyes of the students;

(3) the optical component support frame comprises an optical bread board and a vertical support reflector, wherein a vertical support is vertically arranged on the optical bread board, a plurality of sliding bases are movably arranged on the vertical support along the normal direction of the optical bread board, each sliding base comprises an installation sliding block, a support rod sleeve and a support rod, the installation sliding blocks are movably arranged on the vertical support, the support rod sleeves are vertically fixed on the installation sliding blocks, the support rods are coaxially inserted on the support rod sleeves, the vertical height, the horizontal position and the inclination angle of the optical components can be flexibly adjusted, and each optical component can be independently adjusted and disassembled;

(4) the light source module, the beam expanding module, the polarization control module and one of the reflectors are positioned on the same side of the vertical support, the wavefront modulation module, the beam contracting module, the focusing module, the sample adjusting module, the microscopic module, the monitoring and recording module and the other reflector are positioned on the same side of the vertical support, light beams emitted by an optical component on one side of the vertical support are reflected by the two reflectors and then are incident to the optical component on the other side of the vertical support, the optical components are arranged on two sides of the vertical support, and the two reflectors are connected with a light path, so that the designed light path is prolonged, and the structure is compact;

(5) the polarization control module comprises signal voltage output equipment, and a linear polarization plate, an electric control liquid crystal wave plate and a quarter wave plate which are movably arranged on an optical component support frame, wherein the signal voltage output equipment is arranged on the optical component support frame and is electrically connected with the electric control liquid crystal wave plate;

(6) the sample adjusting module comprises a sample clamping frame, a three-axis fine adjustment platform and a particle sample, wherein the three-axis fine adjustment platform is movably arranged on a vertical support through a sliding base, the sample clamping frame is arranged on the three-axis fine adjustment platform, the particle sample is arranged on the sample clamping frame, the three-axis fine adjustment platform can finely adjust the position of the particle sample in three mutually orthogonal directions in space, and the flexibility is strong;

(7) the first monitoring camera is arranged on the focusing module and used for monitoring and recording the focusing condition and the movement condition of particles in the particle sample in real time, and the object lens and the ocular lens in the microscopic module are used for acquiring and recording the image of the particle sample after amplifying the image, so that the real-time monitoring and recording of the movement condition of the particles in the particle sample are realized, the computer display is realized, the automation level is high, and the operation is simple and convenient.

Drawings

FIG. 1 is a schematic diagram of the apparatus of the present invention;

FIG. 2 is a side view of a right angle optical alignment mount;

fig. 3 is a liquid crystal director distribution diagram of a Q-plate (Q-5) of uniform helical phase distribution;

FIG. 4 is a liquid crystal director distribution plot for a non-uniform helical phase distributed Q-wave plate;

the reference numbers in the figures illustrate:

101. an optical bread board, 102, a vertical bracket, 103, a mounting slider, 104, a supporting rod sleeve, 105, a supporting rod, 106, a reflecting mirror frame, 107, a reflecting mirror, 201, a solid laser, 202, a first adjustable diaphragm, 203, an adjustable optical attenuator, 204, a laser beam, 301, a first lens group, 401, a linear polarizer, 402, a first electric control liquid crystal wave plate, 403, a first quarter wave plate, 404, a second quarter wave plate, 405, a second electric control liquid crystal wave plate, 406, a signal voltage output device, 501, a second adjustable diaphragm, 502, a patterned orientation liquid crystal wave plate, 503, a liquid crystal wave plate adjusting bracket, 601, a second lens group, 701, a right angle optical adjusting bracket, 702, a beam splitter, 703, a first objective lens, 704, an objective lens fine adjusting bracket, 801, a sample bracket, 802, a three-axis fine adjusting platform, 803, a particle sample, 901, a second objective lens, 903, an illumination light source, 904. column, 905, microscope adjusting frame, 906, microscope straight tube, 907, color filter, 908, beam splitter, 1001, first monitoring camera, 1002, protective sheet, 1003, computer, 1004, second monitoring camera.

Detailed Description

The invention is described in detail below with reference to the figures and specific embodiments. The present embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation manner and a specific operation process are given, but the scope of the present invention is not limited to the following embodiments.

Example 1

An optical tweezers device based on a liquid crystal device for experiment teaching and scientific research is shown in figure 1 and comprises an optical component support frame, and a light source module, a beam expanding module, a polarization control module, a wavefront modulation module, a beam shrinking module, a focusing module, a sample adjusting module, a microscopic module and a monitoring and recording module which are arranged on the optical component support frame.

The optical component support frame comprises an optical bread board 101 and a vertical support 102, wherein the vertical support 102 is vertically arranged on the optical bread board 101, a plurality of sliding bases are movably arranged on the vertical support 102 along the normal direction of the optical bread board 101, the number of the reflectors 107 is two, each reflector 107 is fixed on one of the sliding bases through a reflector frame 106, and the two reflectors 107 are symmetrically arranged relative to the vertical support 102;

the vertical support 102 can be an optical guide rail, a support with a magnetic attraction function or a support with a fixing hole, each sliding base comprises an installation sliding block 103, a support rod sleeve 104 and a support rod 105, the installation sliding block 103 is movably arranged on the vertical support 102, the support rod sleeve 104 is vertically fixed on the installation sliding block 103, the support rod 105 is coaxially inserted into the support rod sleeve 104, the telescopic function is achieved, and the height of an optical component and the distance between the optical component and the vertical support 102 can be adjusted through the sliding bases.

The light source module includes solid laser 201, first adjustable diaphragm 202 and adjustable optical attenuator 203 that activity set up on vertical support 102 in proper order, every optical component in the light source module all corresponds a sliding base, adjustable optical attenuator 203 is used for adjusting the intensity of light, if solid laser 201 power is adjustable itself, then need not adjustable optical attenuator 203, still can set up a pinhole filter as required, be used for promoting the light beam quality, if the light beam quality that the light source produced can, then need not the pinhole filter, in this embodiment, the light beam quality that solid laser 201 produced can still, consequently, need not the pinhole filter.

The beam expanding module is used for amplifying laser beams and comprises two first lens groups 301 with different focal lengths, the beam expanding module is movably arranged on the vertical support 102 through a sliding base, and the amplification ratio of the first lens groups 301 is 2-10 times.

The polarization control module can generate light in various polarization states, including left-handed circularly polarized light, right-handed circularly polarized light, linearly polarized light with controllable polarization direction and elliptically polarized light, the polarization control module comprises a signal voltage output device 406, and a linear polarizer 401, a first electric control liquid crystal wave plate 402, a first quarter wave plate 403, a second quarter wave plate 404 and a second electric control liquid crystal wave plate 405 which are sequentially and movably arranged on the vertical support 102, wherein the signal voltage output device 406 is arranged on the optical bread plate 101 and is electrically connected with the second electric control liquid crystal wave plate 405;

the working wavelength of the quarter-wave plate is consistent with the wavelength of the light generated by the light source module;

when the electric control liquid crystal wave plate and the quarter wave plate are used in a matched mode, the effect of changing the polarization state can be achieved by using proper signal voltage, and the effects comprise mutual conversion among circularly polarized light, elliptically polarized light and linearly polarized light and switching between left circularly polarized light and right circularly polarized light;

the signal voltage output device 406 has a function of multi-channel output, and controls each electric control liquid crystal wave plate respectively, and the alternating voltage regulation range is 0-20 volts.

The wavefront modulation module utilizes the liquid crystal geometric phase principle to realize the modulation of the beam wavefront, and comprises a second adjustable diaphragm 501, a patterned oriented liquid crystal wave plate 502 and a liquid crystal wave plate adjusting frame 503, wherein the second adjustable diaphragm 501 and the liquid crystal wave plate adjusting frame 503 are movably arranged on a sliding base, the patterned oriented liquid crystal wave plate 502 is clamped by the liquid crystal wave plate adjusting frame 503, and the position of the patterned oriented liquid crystal wave plate 502 can be finely adjusted in any two mutually perpendicular directions in the horizontal plane;

the number of the patterned oriented liquid crystal wave plates 502 is one or more, and in the embodiment, the number of the patterned oriented liquid crystal wave plates 502 is one;

the geometric phase is a special phase which is different from a dynamic propagation phase and does not depend on an optical path, and is only related to the geometric shape of the arrangement of anisotropic media on the light passing path, the patterned oriented liquid crystal wave plate 502 has patterned orientation, the patterned oriented liquid crystal wave plate 502 can be a passive liquid crystal element made of liquid crystal polymer, namely a substrate of the liquid crystal wave plate does not need a transparent conductive electrode, and can also be an active electric control liquid crystal wave plate with patterned orientation, namely the substrate of the liquid crystal wave plate has a layer of transparent conductive electrode, the patterned oriented liquid crystal wave plate 502 has the advantages of compact structure and high efficiency, the patterned oriented liquid crystal wave plate 502 with the patterned orientation is used for carrying out wavefront modulation on the light beam, the light beam carries the geometric phase, the particles are captured after the light beam is focused, and the specific movement of the particles is realized under the driving of the geometric phase of the light beam, and the method completely meets the requirements of optical tweezers experimental teaching and scientific research, the optical tweezers device has the advantages of simple structure, economy, practicability, strong operability of students and the like;

the patterned orientation can be a common Q wave plate pattern showing uniform spiral phase distribution, that is, the topological charge number Q is uniquely determined, as shown in FIG. 3, when left-handed or right-handed circularly polarized light passes through the patterned oriented liquid crystal wave plate and then acts on the particles through the focusing module, the particles can circularly rotate clockwise or counterclockwise along the annular light beam; the patterned orientation may also be a special Q-wave plate pattern exhibiting non-uniform helical phase distribution, i.e. the topological charge number Q varies with the azimuth, as shown in fig. 4, when left-handed or right-handed circularly polarized light passes through the patterned oriented liquid crystal wave plate and then acts on the particles through the focusing module, the particles can move clockwise or counterclockwise along the helical light beam and be sucked or thrown out by the light beam; the patterned orientation may also be with grating structure patterns, lens structure patterns, generation airy beam structure patterns, and other holographic patterns for corresponding particle manipulation.

The beam-reducing module is used for reducing laser beams and comprises two second lens groups 601 with different focal lengths, the beam-reducing module is movably arranged on the vertical support 102 through a sliding base, and the reducing magnification of the beam-reducing module is 2-10 times.

As shown in fig. 2, the focusing module is used for focusing a light beam carrying a specific phase onto a sample, and includes a right-angle optical adjustment frame 701, a first beam splitter 702, a first objective lens 703 and an objective lens fine adjustment frame 704, where the right-angle optical adjustment frame 701 and the objective lens fine adjustment frame 704 are movably disposed on an optical component support frame, the first beam splitter 702 is disposed on the right-angle optical adjustment frame 701, the first beam splitter 702 is a beam splitter or a beam splitter prism, and the first objective lens 703 is disposed on the objective lens fine adjustment frame 704.

The sample adjusting module comprises a sample holding frame 801, a three-axis fine adjustment platform 802 and a particle sample 803, wherein the three-axis fine adjustment platform 802 is movably arranged on the vertical support 102 through a sliding base, the sample holding frame 801 is arranged on the three-axis fine adjustment platform 802, the particle sample 803 is arranged on the sample holding frame 801, and the three-axis fine adjustment platform 802 can finely adjust the position of the particle sample 803 in three mutually orthogonal directions in space.

The microscopic module is used for amplifying the particle sample 803 and comprises a second objective 901, an ocular 902, lighting equipment, a stand column 904, a microscopic adjusting rack 905, a microscopic straight cylinder 906 and a color filter 907, wherein the stand column 904 is arranged on an optical component support frame, the microscopic adjusting rack 905 is movably arranged on the stand column 904, the microscopic straight cylinder 906 is arranged on the microscopic adjusting rack 905, one end of the microscopic straight cylinder 906 is connected with the second objective 901, the other end of the microscopic straight cylinder 906 is connected with the ocular 902, and the color filter 907 is arranged on the second objective 901;

the illumination device comprises an illumination light source 903 and a second beam splitter 908, the illumination light source 903 and the second beam splitter 908 are arranged on the microscope straight cylinder 906, the second beam splitter 908 is a beam splitter, an included angle between the second beam splitter 908 and the horizontal direction is 45 degrees, the illumination light source 903 emits a light source along the horizontal direction, and the light source is reflected by the second beam splitter 908 and then irradiates the particulate sample 803 through the second beam splitter 901;

the illumination device may also employ an annular shadowless lamp mounted between the particulate sample 803 and the microscopy block;

the second objective 901 can be a microscope objective of 10-100 times or an oil lens of 100 times, and the position of the second objective 901 is finely adjusted in any two mutually perpendicular directions in the horizontal plane;

if the magnification of the second objective 901 is appropriate, the eyepiece 902 may not be needed, and if the laser is too strong, a color filter 907 may be placed in front of the microscopic module to block most of the laser from passing through, so as to protect the microscopic module and the monitoring and recording module.

The monitoring and recording module is used for monitoring and recording the movement of particles in a particle sample 803 in real time and comprises a first monitoring camera 1001, a protective sheet 1002, a computer 1003 and a second monitoring camera 1004, wherein the first monitoring camera 1001 and the second monitoring camera 1004 are both connected with a memory card, the first monitoring camera 1001 and the second monitoring camera 1004 are respectively electrically connected with the computer 1003, the first monitoring camera 1001 is arranged on a right-angle optical adjusting frame 701 and receives laser reflected by the particle sample 803 and transmitted light of the particle sample 803 irradiated by an illuminating light source 903 to monitor and record the focusing condition and the movement of the particles in the particle sample 803 in real time, the protective sheet 1002 is arranged on the first monitoring camera 1001, the protective sheet 1002 is a 25% light attenuation sheet or a color filter to prevent the laser from being too strong to damage a camera photosensitive member, and the second monitoring camera 1004 is arranged on the microscopic module and is used for monitoring and recording the movement of the particles in real time in the particle sample 803, Recording the movement of the particles in the particle sample 803;

the first monitoring camera 1001 is a CCD or CMOS camera, and the second monitoring camera 1004 is a CCD or CMOS camera.

After the light beam passes through the patterned oriented liquid crystal wave plate 502 and carries a specific phase, an included angle between the beam splitting interface of the first beam splitter 702 and the horizontal direction is 45 degrees, the vertical light beam is split into two light beams, namely, the vertically transmitted light beam and the horizontally reflected light beam by the first beam splitter 702, the horizontally light beam can be used for assisting in indicating the optimal position of the patterned oriented liquid crystal wave plate 502 when the horizontal position of the patterned oriented liquid crystal wave plate 502 is finely adjusted, and the part of the light beam can be shielded by a baffle plate so as to protect non-users passing around the equipment; after the vertically transmitted light beam is focused on the particle sample 803 by the objective lens of the second objective lens 901, a part of the vertically transmitted light beam is reflected by the particle sample 803, passes through the second objective lens 901, is reflected by the first beam splitter 702 to the horizontal direction opposite to the previous horizontal light beam, and is received by the first monitoring camera 1001 of the monitoring and recording module, if the laser is too strong, the protective sheet 1002 can be placed in front of the camera lens of the first monitoring camera 1001 to prevent the laser from damaging the camera photosensitive component.

Example 2

In this embodiment, as shown in fig. 1, the optical component support frame further includes two mirrors 107 located at the top of the vertical support 102, each mirror 107 is fixed on one of the sliding bases by a mirror bracket 106, and the two mirrors 107 are symmetrically arranged with respect to the vertical support 102;

if the designed light path is longer, the optical components are divided into two parts, the light source module, the beam expanding module, the polarization control module and one of the reflectors 107 are positioned on the same side of the vertical support 102, the wavefront modulation module, the beam shrinking module, the focusing module, the sample adjusting module, the microscopic module, the monitoring and recording module and the other reflector 107 are positioned on the same side of the vertical support 102, and light beams emitted by the optical components on one side of the vertical support 102 are reflected by the two reflectors 107 and then enter the optical components on the other side of the vertical support 102. The rest is the same as in example 1.

Embodiment 1 and embodiment 2 provide an optical tweezers device based on liquid crystal device for experimental teaching and scientific research, different from commercial optical tweezers in the current market, utilize liquid crystal device to generate specific optical phase, modulate the wave front of light beam, realize specific control of micro-particle spatial motion, have intuitive optical design, easy students understand the working principle, convenient students to practice the experimental operating space, suitable for students of different ages, has remarkable advantages for exciting the physical learning interest of students, cultivating the exploration spirit of students and promoting the scientific literacy of students, the method has the advantages that the method gives attention to the cultivation and interest excitation of students' abilities while considering the scientific research applicability, practically brings zero distance to the students in the scientific and technological frontier of the world, and improves the experimental manipulative ability of the students while expanding the eyes of the students.

The foregoing detailed description of the preferred embodiments of the invention has been presented. It should be understood that numerous modifications and variations could be devised by those skilled in the art in light of the present teachings without departing from the inventive concepts. Therefore, the technical solutions available to those skilled in the art through logic analysis, reasoning and limited experiments based on the prior art according to the concept of the present invention should be within the scope of protection defined by the claims.

Claims (10)

1. An optical tweezers device based on a liquid crystal device and used for experimental teaching and scientific research is characterized by comprising an optical component support frame, and a light source module, a beam expanding module, a polarization control module, a wavefront modulation module, a beam shrinking module, a focusing module, a sample adjusting module, a microscopic module and a monitoring and recording module which are arranged on the optical component support frame;

the wave front modulation module comprises a second adjustable diaphragm (501), a patterned oriented liquid crystal wave plate (502) and a liquid crystal wave plate adjusting frame (503), wherein the second adjustable diaphragm (501) and the liquid crystal wave plate adjusting frame (503) are movably arranged on the optical component support frame, and the patterned oriented liquid crystal wave plate (502) is arranged on the liquid crystal wave plate adjusting frame (503).

2. The optical tweezers device based on the liquid crystal device for experimental teaching and scientific research as claimed in claim 1, wherein the optical component support frame comprises an optical bread board (101) and a vertical support (102), the vertical support (102) is vertically arranged on the optical bread board (101), a plurality of sliding bases are movably arranged on the vertical support (102) along the normal direction of the optical bread board (101), each sliding base comprises a mounting sliding block (103), a support rod sleeve (104) and a support rod (105), the mounting sliding block (103) is movably arranged on the vertical support (102), the support rod sleeve (104) is vertically fixed on the mounting sliding block (103), and the support rod (105) is coaxially inserted into the support rod sleeve (104).

3. The optical tweezers device for experimental teaching and scientific research based on liquid crystal devices according to claim 2, wherein said optical component holder further comprises two mirrors (107), each mirror (107) being fixed to one of the sliding bases by a mirror holder (106), said two mirrors (107) being symmetrically arranged with respect to the vertical support (102), said light source module, beam expansion module, polarization control module and one of the mirrors (107) being located on the same side of the vertical support (102), said wavefront modulation module, beam contraction module, focusing module, sample adjustment module, microscopy module, monitoring and recording module and the other mirror (107) being located on the same side of the vertical support (102).

4. The optical tweezers device based on the liquid crystal device for experimental teaching and scientific research as claimed in claim 1, wherein the light source module comprises a solid laser (201), a first adjustable diaphragm (202) and an adjustable optical attenuator (203) which are movably arranged on the optical component support frame in sequence.

5. The optical tweezers device for experimental teaching and scientific research based on the liquid crystal device as claimed in claim 1, wherein the polarization control module comprises a signal voltage output device (406), and a linear polarizer (401), an electrically controlled liquid crystal wave plate and a quarter wave plate which are movably arranged on the optical component support frame, wherein the signal voltage output device (406) is arranged on the optical component support frame and electrically connected with the electrically controlled liquid crystal wave plate, the electrically controlled liquid crystal wave plate is one or more in number, and the quarter wave plate is one or more in number.

6. The optical tweezers device based on the liquid crystal device for experimental teaching and scientific research as claimed in claim 1, wherein said beam expanding module comprises two first lens sets (301) with different focal lengths, said beam expanding module is movably disposed on the optical component support frame;

the beam-reducing module comprises two second lens groups (601) with different focal lengths, and the beam-reducing module is movably arranged on the optical component support frame.

7. The optical tweezers device based on the liquid crystal device for experimental teaching and scientific research as claimed in claim 1, wherein said focusing module comprises a right-angle optical adjustment frame (701), a first beam splitter (702), a first objective lens (703) and an objective lens fine adjustment frame (704), said right-angle optical adjustment frame (701) and said objective lens fine adjustment frame (704) are movably disposed on the optical component support frame, said first beam splitter (702) is disposed on said right-angle optical adjustment frame (701), and said first objective lens (703) is disposed on said objective lens fine adjustment frame (704).

8. The optical tweezers device for experimental teaching and scientific research based on liquid crystal devices of claim 1, wherein said sample adjustment module comprises a sample holder (801), a three-axis fine adjustment platform (802) and a particle sample (803), said three-axis fine adjustment platform (802) is movably disposed on the optical component holder, said sample holder (801) is disposed on the three-axis fine adjustment platform (802), and said particle sample (803) is disposed on the sample holder (801).

9. The optical tweezers device based on the liquid crystal device for experiment teaching and scientific research according to claim 1, wherein the microscope module comprises a second objective (901), an ocular (902), lighting equipment, a vertical column (904), a microscope adjusting frame (905), a microscope straight cylinder (906) and a color filter (907), the vertical column (904) is arranged on the optical component support frame, the microscope adjusting frame (905) is movably arranged on the vertical column (904), the microscope straight cylinder (906) is arranged on the microscope adjusting frame (905), one end of the microscope straight cylinder (906) is connected with the second objective (901), the other end of the microscope straight cylinder is connected with the ocular (902), the color filter (907) is arranged on the second objective (901), and the lighting equipment is arranged on the microscope straight cylinder (906).

10. The optical tweezers device based on the liquid crystal device for experimental teaching and scientific research according to claim 1, wherein the monitoring and recording module comprises a first monitoring camera (1001), a protection sheet (1002), a computer (1003) and a second monitoring camera (1004), the first monitoring camera (1001) and the second monitoring camera (1004) are respectively electrically connected with the computer (1003), the first monitoring camera (1001) is disposed on the focusing module, the protection sheet (1002) is disposed on the first monitoring camera (1001), and the second monitoring camera (1004) is disposed on the microscopic module.

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