阅读说明：本技术 一种基于光栅莫尔条纹的阵列光镊 (Array optical tweezers based on grating moire fringes ) 是由 肖子峰 任洪亮 陈西满 陈颖静 于 2021-01-05 设计创作，主要内容包括：本发明涉及一种基于光栅莫尔条纹的阵列光镊,利用光栅组产生的莫尔条纹所形成的阵列,用于多个微粒子的捕获与操控。工作过程中,样品池保持静止不动,微粒在环境中不会受到外界的影响,微粒会被莫尔条纹形成的光阱牢牢束缚并跟随其移动从而达到稳定操控的效果。莫尔条纹的放大倍率仅仅取决于两个光栅之间的角度,移动一个光栅节距莫尔条纹的一个周期,会在空间尺度上放大几百倍,在捕获和操纵过程中可以根据不同的精度和范围进行任意调整形成不同阵列。本发明中,莫尔条纹成周期性变化,便于仪器观察和消除随机误差。本发明结构简单,搭建成本低,易于操作,利于商业化的推广。(The invention relates to an array optical tweezers based on grating moire fringes, which utilizes an array formed by the moire fringes generated by a grating group to capture and control a plurality of micro-particles. In the working process, the sample cell keeps still, and the particle can not receive external influence in the environment, thereby the particle can be firmly bound by the optical trap that moire fringe formed and follow its removal and reach the effect of stably controlling. The magnification of moire fringes depends only on the angle between two gratings, one period of moire fringes can be magnified by hundreds of times in the spatial scale by moving one grating pitch, and different arrays can be formed by random adjustment according to different precisions and ranges in the capturing and manipulating processes. In the invention, the moire fringes are periodically changed, so that the observation of an instrument is facilitated and random errors are eliminated. The invention has simple structure, low construction cost and easy operation, and is beneficial to commercial popularization.)

1. The array optical tweezers based on the moire fringes of the grating are characterized by comprising a laser light source, a grating system, an objective lens and a sample platform, wherein the grating system is used for generating the moire fringes, the sample platform is used for generating the moire fringes by laser emitted by the laser light source through the grating system, the moire fringes are introduced into the objective lens and are focused to a sample cell on the sample platform through the objective lens, a multi-optical trap array is generated in the sample cell, and capture and manipulation of particles are achieved.

2. The array optical tweezers based on the grating moire fringes as claimed in claim 1, wherein the grating system comprises a main grating and an indication grating which are sequentially arranged and overlapped with each other, and the included angle between the grating lines of the main grating and the grating lines of the indication grating is adjusted by adjusting the angle or position of the main grating or the indication grating.

3. The array optical tweezers of claim 2, wherein the laser light from the laser light source is incident on the main grating and the indication grating, and forms alternating light with a fixed period after passing through the main grating and the indication grating, thereby generating moire fringes.

4. The array optical tweezers of claim 3, wherein when the main grating and the indication grating move relatively, the intensity of the transmitted laser light changes alternately, and when the indication grating moves n pitches relative to the main grating, the moire fringes correspondingly move n fringe intervals, thereby achieving the manipulation of a plurality of particles.

5. The array optical tweezers based on the grating moire fringes as claimed in claim 1, wherein a beam expanding and collimating system is disposed between the laser source and the grating system, and the laser emitted from the laser source is expanded and shaped by the beam expanding and collimating system, and then enters the grating system.

6. The grating moire fringe based array optical tweezers of claim 1, wherein a telescopic system is further arranged between the grating system and the objective lens, and the moire fringes are irradiated to the objective lens through the telescopic system.

7. The grating moire fringe based array optical tweezers of claim 6, wherein a dichroic mirror is further arranged between the grating system and the telescope system, and the moire fringes are reflected by the dichroic mirror and then enter the telescope system.

8. The array optical tweezers of claim 2, wherein a driving device is further provided to control the rotation or displacement of the main grating or the indication grating in the plane thereof, respectively, so as to adjust the included angle between the grating lines of the main grating and the grating lines of the indication grating.

9. The array optical tweezers based on the grating moire fringes as claimed in any one of claims 1 to 8, wherein an illumination light source, a spectroscope, an imaging device and an analysis system are arranged, and the illumination light source, a sample stage and the spectroscope are arranged in sequence; the spectroscope is used for guiding the moire fringes to enter the objective lens and reflecting the illumination light generated by the illumination light source to the imaging device, and the analysis system acquires an optical image output by the imaging device and processes and analyzes the optical image to obtain an analysis result; or, according to the analysis result obtained by the analysis system, the feedback control driving device adjusts the included angle between the grid line of the main grating and the grid line of the indicating grating.

Technical Field

The invention relates to the technical field of optical control, in particular to array optical tweezers based on grating moire fringes.

Background

Optical tweezers are tools that can clamp and manipulate tiny objects like traditional mechanical tweezers, and capture and manipulate micro-nano-sized particles based on momentum transfer between light and matter. The optical tweezers have unique control on single particles from micrometer to nanometer due to a mild non-mechanical contact mode, and are widely applied to the fields of colloid physics, life science, microfluid and the like.

When the control of multiple cells and multiple molecules is faced, the single focus is still used for controlling and controlling the light capture in a microscopic environment, which is not an efficient choice, in order to realize more complex and diversified functions and higher degree of freedom, the light tweezers are from the original single light tweezers to the multiple light tweezers, and various technologies are combined, so that the novel light field light tweezers in various shapes and colors are continuously presented.

In the prior art, the main methods for generating the multi-optical trap array include a time division multiplexing method, a split optical path method and dynamic holographic optical tweezers. The time-division multiplexing method is used for realizing the optical capture of multiple particles when a single laser beam is time-division multiplexed at a sufficiently high speed to generate focuses at different positions; the split optical path method is to split the laser beam into two beams, such as two-beam interference to realize the redistribution of the intensity of the optical field; dynamic holography is to load a hologram designed by a computer on a spatial light modulator, can generate any complex light field form, and can realize dynamic adjustment.

However, the method of the prior art has a complex structure of the assembled device, high cost and great difficulty in operation, and even the device needs to be replaced for different samples, which cannot meet the requirements of common experimenters.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provides the array optical tweezers based on the grating moire fringes, which are simple in structure, low in construction cost and easy to operate, can generate a multi-optical trap array with adjustable light spot number and size on a sample stage, and can capture and operate a plurality of samples.

The technical scheme of the invention is as follows:

the array optical tweezers based on the grating moire fringes comprise a laser light source, a grating system for generating the moire fringes, an objective lens and a sample platform which are sequentially arranged, wherein laser emitted by the laser light source generates the moire fringes through the grating system, the moire fringes are introduced into the objective lens and are focused to a sample cell on the sample platform through the objective lens, a multi-optical trap array is generated in the sample cell, and capture and manipulation of particles are achieved.

Preferably, the grating system comprises a main grating and an indication grating which are sequentially arranged and mutually overlapped, and an included angle between a grid line of the main grating and a grid line of the indication grating is adjusted by adjusting the angle or the position of the main grating or the indication grating.

Preferably, the laser light emitted from the laser light source is incident on the main grating and the indicator grating, and passes through the main grating and the indicator grating to form alternating light of a fixed period, thereby generating moire fringes.

Preferably, when the main grating and the indicator grating are relatively moved, the intensity of the transmitted laser beam is alternately changed between bright and dark, and when the indicator grating is moved by n small pitches with respect to the main grating, the moire fringes are moved by n fringe intervals in accordance with the moire fringes, thereby manipulating the plurality of particles.

Preferably, a beam expanding and collimating system is arranged between the laser source and the grating system, and laser emitted by the laser source is expanded and shaped by the beam expanding and collimating system and then is incident to the grating system.

Preferably, a telescope system is further provided between the grating system and the objective lens, and the moire fringes are irradiated to the objective lens through the telescope system.

Preferably, a dichroic mirror is further provided between the grating system and the telescopic system, and the moire fringes are reflected by the dichroic mirror and then incident on the telescopic system.

Preferably, a driving device is further arranged to control the main grating or the indicating grating to rotate or displace on the plane where the main grating or the indicating grating is located, and further adjust an included angle between the grid lines of the main grating and the grid lines of the indicating grating.

Preferably, an illumination light source, a spectroscope, an imaging device and an analysis system are arranged, wherein the illumination light source, the sample stage and the spectroscope are arranged in sequence; the spectroscope is used for guiding the moire fringes to enter the objective lens and reflecting the illumination light generated by the illumination light source to the imaging device, and the analysis system acquires an optical image output by the imaging device and processes and analyzes the optical image to obtain an analysis result; or, according to the analysis result obtained by the analysis system, the feedback control driving device adjusts the included angle between the grid line of the main grating and the grid line of the indicating grating.

The invention has the following beneficial effects:

the array optical tweezers based on the grating moire fringes are used for capturing and controlling a plurality of micro-particles by utilizing an array formed by the moire fringes generated by the grating group. In the working process, the sample cell keeps still, and the particle can not receive external influence in the environment, thereby the particle can be firmly bound by the optical trap that moire fringe formed and follow its removal and reach the effect of stably controlling. The magnification of moire fringes depends only on the angle between two gratings, one period of moire fringes can be magnified by hundreds of times in the spatial scale by moving one grating pitch, and different arrays can be formed by random adjustment according to different precisions and ranges in the capturing and manipulating processes. In the invention, the moire fringes are periodically changed, so that the observation of an instrument is facilitated and random errors are eliminated.

The invention has simple structure, low construction cost and easy operation, and is beneficial to commercial popularization.

Drawings

FIG. 1 is a schematic structural view of the present invention;

FIG. 2 is a schematic diagram of the lateral moire fringes formed by the grating system;

FIG. 3 is a schematic diagram of an array of dots formed in a sample cell by transverse moire fringes;

in the figure: 10 is a laser light source, 11 is a beam expanding collimation system, 12 is a grating system, 13 is a dichroic mirror, 14 is a telescope system, 15 is an objective lens, 16 is a sample stage, 17 is a sample cell, 20 is a spectroscope, 21 is an imaging device, 22 is an analysis system, and 23 is an illumination light source.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples.

In order to solve the defects in the prior art, the present invention provides an array optical tweezers based on grating moire fringes, as shown in fig. 1, which includes a laser light source 10, a beam expanding collimation system 11, a grating system 12 for generating moire fringes, a dichroic mirror 13, a telescopic system 14, a spectroscope 20, an objective lens 15 (which may adopt a microscope objective lens 15 with a relatively high numerical aperture), a sample stage 16, an illumination light source 23, an imaging device 21 (such as a CMOS camera), an analysis system 22 (such as a PC), wherein the spectroscope 20, the imaging device 21, and the analysis system 22 are sequentially arranged. Laser emitted by a laser source 10 is expanded by a beam expanding and collimating system 11, collimated and shaped, and then enters a grating system 12; the light beam generates moire fringes through the grating system 12; the moire fringes are reflected by a dichroic mirror 13 and then enter a telescopic system 14; the moire fringes are irradiated to the objective lens 15 through the telescope system 14; moire fringes are introduced into an objective lens 15, focused to a sample cell 17 on a sample stage 16 through the objective lens 15, and a multi-optical trap array is generated in the sample cell 17, so that the particles are captured and manipulated. The beam splitter 20 is used to direct the moire fringes into the objective lens 15; meanwhile, the illumination light generated by the illumination light source 23 is reflected to the imaging device 21, further, the image of the capturing and manipulating process of the present invention is transmitted to the imaging device 21 through the lens image, after the image information is collected, the analysis system 22 acquires the optical image output by the imaging device 21, and processes and analyzes the optical image to obtain the analysis result.

In this embodiment, the beam expanding and collimating system 11 is a beam coupler composed of two lenses; the telescopic system 14 is composed of two lenses. The grating system 12 includes a main grating and an indication grating which are sequentially arranged and overlapped with each other, and a smaller included angle is formed between the grating lines of the main grating and the grating lines of the indication grating, as shown in fig. 2. Laser emitted by the laser source 10 is incident on the main grating and the indicating grating, alternating light with a fixed period is formed after the laser penetrates through the main grating and the indicating grating, moire fringes are generated, a multi-optical-trap array is formed on the sample cell 17, and particles are captured. When relative motion is generated between the main grating and the indicating grating, the light intensity of the transmitted laser is changed alternately in bright and dark, and when the indicating grating moves by n small pitches relative to the main grating, the Moire fringes correspondingly move by n fringe intervals, so that the control of a plurality of particles is realized. In this embodiment, the pitches (grating pitches) of the main grating and the indication grating may be equal or different, and are determined according to the specific use environment.

The included angle between the grid lines of the main grating and the grid lines of the indicating grating is adjusted by adjusting the angle or the position of the main grating or the indicating grating to form Moire fringes in different directions, so that the shape of the array is changed, the capture in different precision and ranges in the particle group is realized, and the individual capture requirements of the particles in different precision and different ranges are met.

In this embodiment, an included angle between the grid lines is adjusted to obtain a horizontal moire fringe, and a horizontally arranged particle capture array is formed, specifically, P1 is set to represent a grid pitch of the main grating, P2 is set to represent a grid pitch of the indication grating, and θ is set to represent an included angle between the grid line of the main grating and the grid line of the indication grating; then, when P1 is equal to P2cos θ, the grating system 12 generates lateral moire fringes, as shown in fig. 2 (in the figure, B is the width of the moire fringes), forming a laterally aligned particle capture array, as shown in fig. 3.

When the displacement of the indicator grating is adjusted, the moire fringes can be moved, enabling movement of a plurality of particles captured in the array. Moire fringes enlarge displacementWhen the moire fringes move P2, the moire fringes move by one moire width and the particle population steadily follows the moire beam movement in the array.

In order to adjust the angle or position of the main grating or the indication grating, the invention is further provided with a driving device (such as a motor, not shown in the figure) which respectively controls the main grating or the indication grating to rotate or displace on the plane where the main grating or the indication grating is located, so as to adjust the included angle between the grid lines of the main grating and the grid lines of the indication grating. The particle capture array can drive the main grating or the indicating grating to deflect slightly through the driving device, so that the included angle between the grid lines is changed slightly, and the shape and the precision of the array are set.

Further, according to the analysis result obtained by the analysis system 22, the feedback control driving device adjusts the included angle between the grid line of the main grating and the grid line of the indication grating, so as to realize the deflection and movement of the main grating or the indication grating, and change the particle capture array.

The above examples are provided only for illustrating the present invention and are not intended to limit the present invention. Changes, modifications, etc. to the above-described embodiments are intended to fall within the scope of the claims of the present invention as long as they are in accordance with the technical spirit of the present invention.