Pocket optical tweezers

Abstract

The pocket optical tweezers comprise an optical tweezers optical path, a touch screen, a main control system and a battery, the optical tweezer optical path comprises a laser, a laser shaping optical path, a dichroic reflector, an imaging system, a camera, a microscope objective system, a sample flow cell and an illumination system; the laser emits laser with fixed wavelength, and the laser shaping light path shapes the emitted laser; the shaped laser is reflected into a microscope objective system through a dichroic reflector, is focused by the microscope objective system to form a light trap, and enters a sample flow cell to capture particles; the illumination system is used for illuminating the sample flow cell; particles in the sample flow cell are obtained through the imaging system and the camera and are displayed by the touch screen; the wavelength of laser emitted by the laser is 785 nm, the rated power of the laser is 80 mW, the beam divergence angle (FWHM) theta is 7.0 degrees, the horizontal divergence angle (FWHM) theta perpendicular to 17.0 degrees, and the astigmatism As is 10 degrees. The total length of a laser light path is 101.44 mm, and the maximum net diameter of the lens is 7.25 mm.

Description

Technical Field

[0001] The invention relates to the field of optical tweezers, and in particular to a pair of pocket optical tweezers. Background Art

[0002] Optical tweezers can generate optical traps by focusing laser beams, and control microparticles such as biological cells to make them move or suspend. At present, the common commercial optical tweezers at home and abroad mainly come from Elliot Company and BNS Company in the UK, Aresis Company in Germany, Thorlabs Company in the United States, Zhongke Optical Tweezers in China, Xi'an Institute of Optics and Precision Mechanics of the Chinese Academy of Sciences and other institutions. These optical tweezers systems have good working performance and imaging quality. Figure 1 The following are optical tweezers from Aresis, Germany. Figure 2 Shown are optical tweezers from Thorlabs, an American company.

[0003] As can be seen from the figure, although there are many optical tweezers products, most commercial optical tweezers and self-assembled optical tweezers are built on a microscope platform, usually with dimensions of 700mm×300mm×400mm, and have problems such as high cost, large size, heavy weight, need for an ultra-stable workbench, and inability to be portable. Therefore, designing an optical tweezer the size of a mobile phone has important practical value. Summary of the invention

[0004] The present invention provides a pocket optical tweezers, which greatly reduces the external dimensions of the optical tweezers device to the size of a mobile phone, thereby achieving ultra-small, portable, lightweight and integrated optical tweezers device.

[0005] In order to solve the above problems, the present invention provides a pocket optical tweezers, including an optical tweezers optical path, a touch screen, a main control system and a battery; the optical tweezers optical path includes a laser, a laser shaping optical path, a dichroic reflector, an imaging system, a camera, a microscope objective system, a sample circulation pool, and an illumination system;

[0006] The laser emits a fixed wavelength laser, and the laser shaping optical path shapes the emitted laser; the shaped laser is reflected by a dichroic reflector into the microscope objective system, and after being focused by the microscope objective system, a light trap is formed and enters the sample flow cell to capture particles; the illumination system illuminates the sample flow cell; the particles in the sample flow cell are acquired through the imaging system and the camera and displayed on the touch screen;

[0007] The laser wavelength emitted by the laser is 785nm, the laser rated power is 80mW, and the beam divergence angle = (FWHM)θ || =7.0°, horizontal divergence angle (FWHM)θ ⊥ =17.0°, astigmatism A s =10°;

[0008] The total length of the laser optical path is 101.44mm, and the maximum net diameter of the lens is 7.25mm.

[0009] In some of the embodiments, the laser shaping optical path performs astigmatism correction, collimation and beam expansion shaping. The laser astigmatism correction part is composed of two mutually perpendicular cylindrical lenses, which collimate the laser from the meridian plane and the sagittal plane respectively; after the astigmatism correction part, a Galilean beam expansion system is designed using a positive and negative lens combination of a plano-concave lens and a plano-convex lens.

[0010] In some of the embodiments, a space is reserved between the laser and the cylindrical lens of the astigmatism correction part to install a half-wave plate or a polarizer.

[0011] In some of the embodiments, the microscope objective lens system uses an oil immersion objective lens composed of multiple lenses, the microscope objective lens system has a total length of 46.568 mm, a maximum net diameter of 7.25 mm, and a numerical aperture NA of 0.87.

[0012] In some of the embodiments, the refractive index of the lens of the position-limiting objective system is 1.52.

[0013] In some embodiments, the imaging system includes a photographic eyepiece, wherein the photographic eyepiece is composed of a plano-convex lens and a doublet lens, with a total focal length D 目 =13.56mm, total length 30.45242mm.

[0014] In some of the embodiments, the lighting system includes an LED chip and a beam shaping optical path, and the beam shaping optical path can utilize a laser shaping optical path or an imaging optical path.

[0015] In some of the embodiments, the main control system is connected to the driver of the laser to control laser emission, and is connected to the camera to receive image signals; it also has a wireless signal connection function.

[0016] In some of these embodiments, the touch screen is also used to control laser power.

[0017] Compared with the prior art, the present invention reduces the optical path to the size of a palm through the design of the optical path of the optical tweezers, greatly reducing the external dimensions of the optical tweezers device, which can be reduced to the size of a mobile phone. Users can easily take the optical tweezers out of the laboratory and realize applications in multiple scenarios, and the structure is simple. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 Optical tweezers from Aresis;

[0019] Figure 2 The OTKB optical tweezers from Thorlabs.

[0020] Figure 3This is the overall structure diagram of the optical tweezers;

[0021] Figure 4 This is the lens layout diagram of the microscope objective system;

[0022] Figure 5 This is a schematic diagram of the optical tweezers device model;

[0023] Figure 6 for Figure 5 Top view of the . DETAILED DESCRIPTION

[0024] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention; it is obvious that the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments, and all other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making creative work are within the scope of protection of the present invention.

[0025] This embodiment provides a pocket optical tweezers, including an optical tweezers optical path, a touch screen, a main control system and a battery;

[0026] The optical tweezers optical path includes a laser and its shaping system, i.e., a laser and a laser shaping optical path, and also includes a dichroic reflector, an imaging system, a camera, a microscope objective system, a sample flow cell, and an illumination system;

[0027] The laser emits a fixed wavelength laser, and the laser shaping optical path shapes the emitted laser; the shaped laser is reflected by a dichroic reflector into the microscope objective system, and after being focused by the microscope objective system, a light trap is formed and enters the sample flow cell to capture particles; the illumination system illuminates the sample flow cell; the particles in the sample flow cell are acquired through the imaging system and the camera and displayed on the touch screen;

[0028] The laser is a semiconductor laser, the laser wavelength emitted by the laser is 785nm, the laser rated power is 80mW, and the beam divergence angle is (FWHM)θ || =7.0°, horizontal divergence angle (FWHM)θ ⊥ =17.0°, astigmatism A s =10°;

[0029] The laser shaping optical path performs astigmatism correction, collimation and beam expansion shaping. The laser astigmatism correction part is composed of two mutually perpendicular cylindrical lenses, which collimate the laser from the meridian plane and the sagittal plane directions respectively.

[0030] Table 1 Some parameters of laser astigmatism correction:

[0031] Surface type Radius of curvature thickness Material Net diameter Mechanical semi-diameter Cone coefficient Object plane standard surface unlimited 3.000 0.000 0.000 0.000 Standard surface 2.646 2.500 BK7 1.212 1.432 -4.095 Standard surface 1431.684 5.000 1.432 1.432 8.443E+05 Standard surface 12.641 2.500 BK7 2.209 2.300 -6.522 Standard surface -16.954 10.000 2.300 2.300 -11.555 Aperture standard surface unlimited 0.000 2.301 2.301 0.000 Image plane standard surface unlimited 2.301 2.301 0.000

[0032] A 3mm gap is reserved between the laser and the cylindrical lens of the astigmatism correction part to install a half-wave plate or polarizer. The driving current can be adjusted to adjust the laser optical power.

[0033] After the astigmatism correction part, a Galilean beam expansion system is designed using a plano-concave lens and a plano-convex lens in a positive and negative lens combination. This reduces the aberration caused by the spherical mirror and avoids a series of problems such as heat and refractive index change caused by focusing, so that the laser beam can fill the entrance pupil of the microscope objective after expansion, ensuring the realization of optical tweezers.

[0034] Table 2 Beam expansion system lens parameters

[0035]

[0036]

[0037] The microscope objective system is used for imaging and also realizes laser focusing to capture particles and achieve the effect of tweezers. In this embodiment, an oil-immersed objective lens composed of thirteen lenses is designed. Objective oil and a sample pool should be added to the end of the objective lens. The refractive index of the objective oil and the glass should be consistent to increase the object side aperture angle of the objective lens. After optimization, the lens with a refractive index of 1.52 can be well adapted to the objective lens. The reason for selecting an oil-immersed objective lens is to increase the numerical aperture NA of the objective lens to improve the capture performance of the optical tweezers. The total length of the microscope objective lens is 47.568 mm, the maximum net diameter is 7.25 mm, and the numerical aperture NA can be obtained by tracing the edge light path to obtain a value of 0.87.

[0038] Table 3 Microscope objective lens parameters

[0039]

[0040]

[0041] In this embodiment, the total length of the laser optical path is 101.44 mm, and the maximum net diameter of the lens is 7.25 mm. After removing the 3 mm working distance pre-given to the laser, the net size of the lens of the entire optical path is only 98.44 mm×7.25 mm.

[0042] In the imaging system of this embodiment, a photographic eyepiece is included. The main function of the photographic eyepiece is to collimate and focus the image information transmitted in parallel through the dichroic mirror onto the camera behind the eyepiece. The photographic eyepiece is composed of a plano-convex lens and a double-cemented lens to reduce the spherical aberration of the lens. The photographic eyepiece is composed of a plano-convex lens and a double-cemented lens, with a total focal length D 目 =13.56mm, total length 30.45242mm.

[0043] Table 4 Camera eyepiece lens parameters

[0044] Surface type Radius of curvature thickness Material Net diameter Mechanical semi-diameter Cone coefficient Object plane standard surface unlimited unlimited 0.000 0.000 0.000 Aperture standard surface unlimited 10.000 3.000 3.000 0.000 Standard surface unlimited 3.000 N-BK7 3.000 3.000 -2.450E+08 Standard surface -15.402 0.641 3.000 3.000 -2.243 Standard surface 20.622 3.496 P-SK58A 2.888 2.888 -4.330 Standard surface -5.771 3.019 F2 2.584 2.888 -0.545 Standard surface -26.967 10.000 2.226 2.888 0.000 Image plane unlimited 2.630 3.000 0.000

[0045] In this embodiment, the lighting system includes an LED chip and a beam shaping optical path, and the beam shaping circuit can use a laser shaping optical path or an imaging optical path (photographic eyepiece optical path).

[0046] The main control system is connected to the driver of the laser to control laser emission and connected to the camera to receive image signals; the touch screen is also used to control the laser power. Therefore, when using, the user can set it through the touch screen and transmit it to the main control system to control laser emission. The main control system also has Bluetooth and WIFI wireless signal connection functions.

[0047] In this embodiment, the optical tweezers optical path is designed so that the total length of the entire laser optical path is 101.44mm, and the maximum net diameter of the lens is 7.25mm. After removing the 3mm working distance pre-given to the laser, the net size of the lens of the overall optical path is only 98.44mm×7.25mm. This allows the entire optical path of the system to be less than 150mm×110mm×10mm, and the entire system to be as small as 150mm×110mm×20mm. The dimensions of the optical tweezers device are greatly reduced, and can be reduced to the size of a mobile phone. Users can easily take the optical tweezers out of the laboratory and realize applications in multiple scenarios.

[0048] The above is only a preferred specific implementation of the present invention, but the design concept of the present invention is not limited to this. Any technician familiar with the technical field who uses this concept to make non-substantial changes to the present invention within the technical scope disclosed by the present invention shall be deemed to infringe the protection scope of the present invention.

Claims

1. A pocket optical tweezers, characterized in that: It includes an optical tweezers optical path, a touch screen, a main control system and a battery; the optical tweezers optical path includes a laser, a laser shaping optical path, a dichroic reflector, an imaging system, a camera, a microscope objective system, a sample circulation pool and an illumination system; The laser emits a fixed wavelength laser, and the laser shaping optical path shapes the emitted laser; the shaped laser is reflected by the dichroic reflector into the microscope objective system, and after being focused by the microscope objective system, a light trap is formed and enters the sample flow cell to capture particles; The lighting system illuminates the sample flow cell; the particles in the sample flow cell are acquired through the imaging system and the camera and displayed on the touch screen; The laser wavelength emitted by the laser is 785nm, the laser rated power is 80mW, and the beam divergence angle = (FWHM)θ || =7.0°, horizontal divergence angle (FWHM)θ ⊥ =17.0°, astigmatism A s =10°; The total length of the laser optical path is 101.44mm, and the maximum net diameter of the lens is 7.25mm.

2. The pocket optical tweezers according to claim 1, characterized in that: The laser shaping optical path performs astigmatism correction, collimation and beam expansion shaping. The laser astigmatism correction part is composed of two mutually perpendicular cylindrical lenses, which collimate the laser from the meridian plane and the sagittal plane respectively; after the astigmatism correction part, a Galilean beam expansion system is designed using a positive and negative lens combination of a plano-concave lens and a plano-convex lens.

3. The pocket optical tweezers according to claim 2, characterized in that: A gap is reserved between the laser and the cylindrical lens of the astigmatism correction part to install a half-wave plate or a polarizer.

4. The pocket optical tweezers according to claim 1, characterized in that: The microscope objective lens system adopts an oil-immersion objective lens composed of multiple lenses. The microscope objective lens system has a total length of 46.568 mm, a maximum net diameter of 7.25 mm, and a numerical aperture NA of 0.

87.

5. The pocket optical tweezers according to claim 4, characterized in that: The refractive index of the lens of the position-limiting objective system is 1.

52.

6. The pocket optical tweezers according to claim 1, characterized in that: The imaging system includes a photographic eyepiece, which is composed of a plano-convex lens and a doublet lens, with a total focal length D 目 =13.56mm, total length 30.45242mm.

7. The pocket optical tweezers according to claim 1, characterized in that: The lighting system includes an LED chip and a beam shaping optical path, and the beam shaping circuit can utilize a laser shaping optical path or an imaging optical path.

8. The pocket optical camera according to any one of claims 1 to 7, characterized in that: The main control system is connected to the driver of the laser to control laser emission and is connected to the camera to receive image signals; it also has a wireless signal connection function.

9. The pocket optical camera according to any one of claims 1 to 7, characterized in that: The touch screen is also used to control the laser power.

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