Automatic focusing device for light beam detection

Abstract

The utility model relates to an automatic focusing device for light beam detection. The device comprises a laser assembly, an optical assembly, an imaging assembly and a controller. The controller is connected with the laser assembly and the imaging assembly. The laser assembly is used for emitting a first laser beam meeting a preset condition; the optical assembly is used for adjusting the first laser beam, enabling a second laser beam obtained through adjustment to enter a sample through an objective lens of a microscope, and transmitting a third laser beam returned from the sample to the imaging assembly; the imaging assembly is used for generating a focusing signal according to the third laser beam; the controller is used for outputting a control signal according to the focusing signal, and the control signal is used for controlling the objective lens or an objective table of the microscope to move so as to complete focusing. By adopting the device, the focus can be quickly switched under different working conditions.

Description

Technical Field

[0001] The present application relates to the field of microscopic imaging technology, and in particular to a light beam detection autofocus device. Background Art

[0002] In the fields of materials, biology, etc., in order to detect the microscopic conditions of various samples, it is necessary to use microscopic detection platforms such as microscopes to detect the shape and characteristics of the samples. Ordinary microscopic detection platforms often have a low depth of field (millimeter to nanometer level), and the distance that can maintain clarity in the field of view is short. Therefore, in order to achieve clear measurement of the sample to be tested, it is necessary to ensure the focus clarity of the microscope system.

[0003] In traditional technology, focusing is mainly carried out by methods such as structured light projection, critical angle method, eccentric beam method, and astigmatism method. Taking structured light projection as an example, focusing is achieved by adjusting the focal length of the projector. The projector projects a set of known patterns onto the surface of an object, and uses a camera to capture the deformation of these patterns to calculate the three-dimensional shape of the object's surface. In order to ensure the clarity of the pattern, the projector needs to adjust the position of the lens or the focal length of the optical system according to the distance between the object and the projector, so that the projected pattern can be accurately imaged on the surface of the object.

[0004] However, it is difficult for the above device to quickly switch the focus under different working conditions. Utility Model Content

[0005] Based on this, it is necessary to provide a beam detection autofocus device that can quickly switch focus under different working conditions to address the above technical problems.

[0006] The present application provides a beam detection autofocus device, which includes a laser component, an optical component, an imaging component and a controller; the controller is connected to the laser component and the imaging component respectively;

[0007] The laser assembly is used to emit a first laser beam that meets preset conditions;

[0008] The optical component is used to adjust the first laser beam, and to make the adjusted second laser beam incident on the sample through the objective lens of the microscope, and to transmit the third laser beam returned from the sample to the imaging component;

[0009] The imaging component is used to generate a focus signal according to the third laser beam;

[0010] The controller is used to output a control signal according to the focus signal, wherein the control signal is used to control the movement of the objective lens or the stage of the microscope to achieve focusing.

[0011] In one embodiment, the optical assembly includes a first beam splitter and a second beam splitter;

[0012] The first beam splitter is used to transmit the first laser beam to the second beam splitter;

[0013] The second beam splitter is used to adjust the transmission direction of the first laser beam transmitted by the first beam splitter to obtain the second laser beam, and to adjust the transmission direction of the third laser beam returned from the sample to transmit the third laser beam to the first beam splitter;

[0014] The first beam splitter is further used to adjust the transmission direction of the third laser beam transmitted by the second beam splitter, so as to transmit the third laser beam to the imaging component.

[0015] In one embodiment, the transmittance of the first beam splitter is equal to the reflectivity.

[0016] In one embodiment, the second beam splitter is a dichroic mirror; the dichroic mirror is used to block the first laser beam from entering the imaging device of the microscope.

[0017] In one embodiment, the above device further comprises a lens assembly, wherein the lens assembly is arranged between the first beam splitter and the second beam splitter;

[0018] The lens assembly is used to converge the first laser beam.

[0019] In one embodiment, the lens assembly comprises a concave cylindrical lens and a convex lens; the concave cylindrical lens is arranged on a side close to the first beam splitter; the convex lens is arranged on a side close to the second beam splitter;

[0020] The concave cylindrical lens is used to direct the long axis of the first laser beam to be incident on the front focal plane of the objective lens as parallel light;

[0021] The convex lens is used to converge the short axis of the first laser beam at the front focal plane of the objective lens.

[0022] In one embodiment, the controller is connected to the convex lens;

[0023] The controller is also used to adjust the position of the convex lens to change the focus position.

[0024] In one embodiment, the laser assembly comprises a laser and a knife-edge aperture; the knife-edge aperture is arranged between the laser and the optical assembly;

[0025] The laser is used to emit an original laser beam;

[0026] The knife-edge aperture is used to block the long-axis direction of the original laser beam to obtain the first laser beam.

[0027] In one embodiment, the imaging assembly includes a focusing mirror and a detection charge coupled device;

[0028] A converging mirror, used for converging the third laser beam;

[0029] A detection charge coupled device is used to generate the focus signal according to the third laser beam.

[0030] In one of the embodiments, the position between the focusing mirror and the detection charge coupled device is adjustable, and the distance between the focusing mirror and the detection charge coupled device is not less than a preset value.

[0031] The above-mentioned beam detection autofocus device includes a laser component, an optical component, an imaging component and a controller; the controller is connected to the laser component and the imaging component respectively; the laser component is used to emit a first laser beam that meets preset conditions; the optical component is used to adjust the first laser beam, and to make the adjusted second laser beam incident on the sample through the objective lens of the microscope, and to transmit the third laser beam returned from the sample to the imaging component; the imaging component is used to generate a focus signal according to the third laser beam; the controller is used to output a control signal according to the focus signal, wherein the control signal is used to control the movement of the objective lens or the stage of the microscope to complete the focus; when researchers or technicians need to quickly switch to observe different samples, the beam detection autofocus device can quickly adjust the focus between different samples without the need for long-term manual adjustment, thereby improving work efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions in the embodiments of the present application or related technologies, the drawings required for use in the embodiments of the present application or related technical descriptions will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0033] FIG1 is a schematic structural diagram of a light beam detection autofocus device in one embodiment;

[0034] FIG2 is a schematic structural diagram of a light beam detection autofocus device in another embodiment;

[0035] FIG3 is a schematic structural diagram of a light beam detection autofocus device in another embodiment;

[0036] FIG4 is a schematic structural diagram of a light beam detection autofocus device in another embodiment;

[0037] FIG5 is a schematic structural diagram of a light beam detection autofocus device in another embodiment;

[0038] FIG6 is a schematic structural diagram of a light beam detection autofocus device in another embodiment;

[0039] FIG7 is a schematic structural diagram of a light beam detection autofocus device in another embodiment;

[0040] Description of reference numerals:

[0041] Laser assembly 10; Laser 101; Knife-edge aperture 102;

[0042] Optical component 20; First beam splitter 201; Second beam splitter 202;

[0043] Dichroic mirror 2021; Imaging assembly 30; Converging mirror 301;

[0044] Detection charge coupled device 302; Controller 40; Lens assembly 50;

[0045] Concave cylindrical lens 501; Convex lens 502. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0047] In the fields of materials, biology, etc., in order to detect the microscopic conditions of various samples, it is necessary to use microscopic detection platforms such as microscopes to detect the shape and characteristics of the samples. Ordinary microscopic detection platforms often have a low depth of field (millimeter to nanometer level), and the distance that can maintain clarity in the field of view is short. Therefore, in order to achieve clear measurement of the samples to be tested, it is necessary to ensure the focus clarity of the microscope system through manual or automated methods.

[0048] Manual focus adjustment has certain subjectivity and limitations in the test process, and can only focus on the position with a certain pattern. With the development of automated machines and intelligent equipment, it has become increasingly difficult to meet the needs of modern industrial fields by manually adjusting the focus of microscopes. For example, in assembly line operations, the speed of manual focus has greatly limited the speed of assembly line inspection. Therefore, it is necessary to use autofocus to assist automated production.

[0049] There are many types of autofocus methods, and there are many related solutions now. They are generally divided into two categories: passive autofocus technology and active autofocus technology. Passive focus technology uses the imaging device itself to form an image and perform algorithm judgment, which is similar to the principle of human eye judgment; active focus technology uses other auxiliary light sources and related devices outside the imaging system to assist the system in focusing. The focusing process does not depend on the morphology of the sample itself or whether there is a recognizable pattern. It uses the method of light beam shape or property detection for high-precision focus detection, which is more suitable for short-distance and high-precision focusing of microscopic equipment. This solution is a type of active focus technology. Other active focus methods currently available are commonly used methods such as structured light projection, critical angle method, eccentric beam method, astigmatism method, etc. However, the structures of other active focus methods are often designed specifically according to the working conditions, and it is difficult to switch quickly under different working conditions.

[0050] In order to solve the above problems, the present application proposes a light beam detection autofocus device, which, compared with other technologies, can achieve the effect of quickly switching focus under different working conditions.

[0051] An embodiment of the present application provides a beam detection autofocus device, as shown in Figure 1, the beam detection autofocus device includes a laser component 10, an optical component 20, an imaging component 30 and a controller 40; the controller 40 is connected to the laser component 10 and the imaging component 30 respectively; the laser component 10 is used to emit a first laser beam that meets preset conditions; the optical component 20 is used to adjust the first laser beam, and to make the adjusted second laser beam incident on the sample through the objective lens of the microscope, and to transmit the third laser beam returned from the sample to the imaging component 30; the imaging component 30 is used to generate a focus signal according to the third laser beam; the controller 40 is used to output a control signal according to the focus signal, wherein the control signal is used to control the movement of the objective lens or the stage of the microscope to complete the focusing.

[0052] The laser assembly 10 is used to emit a first laser beam that meets preset conditions. The preset conditions may include the wavelength, intensity and beam shape of the laser to make it suitable for specific detection and imaging requirements.

[0053] The optical component 20 is used to make a series of adjustments to the first laser beam, including beam collimation, shape correction and convergence operations, to generate an adjusted second laser beam, and to inject it onto the sample through the objective lens of the microscope. At the same time, the optical component 20 also processes the third laser beam reflected from the sample and transmits it to the imaging component 30. The imaging component 30 receives the third laser beam and generates a focus signal according to its characteristics.

[0054] The controller 40 can analyze the focus state of the sample in real time and generate corresponding control signals by receiving the focus signal from the imaging assembly 30. These control signals are used to adjust the position of the objective lens or the stage of the microscope so that the sample is in the best focus state, thereby achieving high-precision automatic focusing.

[0055] The beam detection autofocus device in the above embodiment includes a laser component, an optical component, an imaging component and a controller; the controller is connected to the laser component and the imaging component respectively; the laser component is used to emit a first laser beam that meets preset conditions; the optical component is used to adjust the first laser beam, and to incident the adjusted second laser beam onto the sample through the objective lens of the microscope, and to transmit the third laser beam returned from the sample to the imaging component; the imaging component is used to generate a focusing signal according to the third laser beam; the controller is used to output a control signal according to the focusing signal, wherein the control signal is used to control the movement of the objective lens or the stage of the microscope to complete the focusing; when researchers or technicians need to quickly switch to observe different samples, the beam detection autofocus device can quickly adjust the focus between different samples without the need for long-term manual adjustment, thereby improving work efficiency.

[0056] The embodiment of Figure 2 provides another beam detection autofocus device. As shown in Figure 2, the optical component 20 includes a first beam splitter 201 and a second beam splitter 202; the first beam splitter 201 is used to transmit the first laser beam to the second beam splitter 202; the second beam splitter 202 is used to adjust the transmission direction of the first laser beam transmitted by the first beam splitter 201 to obtain the second laser beam, and adjust the transmission direction of the third laser beam returned from the sample to transmit the third laser beam to the first beam splitter 201; the first beam splitter 201 is also used to adjust the transmission direction of the third laser beam transmitted by the second beam splitter 202 to transmit the third laser beam to the imaging component 30.

[0057] First, the first beam splitter 201 transmits the first laser beam emitted by the laser assembly 10 to the second beam splitter 202. After receiving the laser beam transmitted by the first beam splitter 201, the second beam splitter 202 adjusts its direction to generate a second laser beam. In addition, the second beam splitter 202 is also responsible for processing the third laser beam reflected from the sample, adjusting its transmission direction and transmitting it back to the first beam splitter 201. After receiving the third laser beam, the first beam splitter 201 adjusts the transmission direction again so that the third laser beam can be transmitted to the imaging assembly 30. The imaging assembly 30 receives and processes the third laser beam to generate a focus signal.

[0058] In the above embodiment, the light signal received by the imaging component can be effectively optimized by the first beam splitter and the second beam splitter, thereby improving the imaging quality. By accurately controlling the transmission direction of the laser beam, a more precise focusing operation can be achieved, so that the imaging focus is always located in the sample area of ​​interest, thereby improving the accuracy and stability of focusing.

[0059] In another beam detection autofocus device, referring to FIG. 2 , the transmittance of the first beam splitter 201 is equal to the reflectance.

[0060] The transmittance of the first beam splitter 201 is equal to the reflectance, that is, 50% of the incident light beam will be transmitted through it, and 50% of the incident light beam will be reflected back.

[0061] In some embodiments, the first beam splitter 201 has multiple options, and different optical elements such as non-polarizing beam splitting cube prisms or flat beam splitters can be used. For the function of the optical path, a non-polarizing beam splitter with a transmittance equal to a reflectance is generally selected, but the use conditions of the first beam splitter 201 are not limited as long as the function is met.

[0062] In the above embodiment, firstly, the equal transmittance and reflectance result in a uniform distribution of the beam energy, so that the first laser beam maintains a stable intensity distribution during the transmission and adjustment process. For the first laser beam transmitted to the second beam splitter, this uniform distribution helps to keep the shape and intensity of the beam consistent in subsequent adjustments. Secondly, when the third laser beam is reflected back from the sample and transmitted to the first beam splitter, the equal proportion of transmission and reflection enables the energy of the return beam to be effectively distributed to the imaging component, thereby improving the imaging quality and the accuracy of the focus signal.

[0063] In another beam detection autofocus device, as shown in FIG. 2 , the second beam splitter 202 is a dichroic mirror 2021 ; the dichroic mirror 2021 is used to block the first laser beam from entering the imaging device of the microscope.

[0064] The dichroic mirror 21 is a special optical element having different transmittance and reflectance for light of different wavelengths. The main function of the dichroic mirror 21 is to block the first laser beam from entering the imaging device of the microscope.

[0065] Specifically, the dichroic mirror 2021 can accurately separate the laser beam and the imaging beam: when the first laser beam is transmitted to the dichroic mirror 2021, the dichroic mirror 2021 will reflect or transmit the first laser beam according to the preset spectral characteristics. Generally, the dichroic mirror 2021 will reflect the laser beam of the infrared band or other specific wavelengths, thereby preventing the first laser beam from entering the imaging device of the microscope and preventing interference with the imaging quality. At the same time, the dichroic mirror 2021 allows visible light or other imaging bands to pass through, thereby ensuring the accuracy and clarity of the microscope imaging.

[0066] In some embodiments, there are multiple options for the dichroic mirror 2021. The dichroic mirror 2021 is a special beam splitter that has different transmittances and reflectances for light of different wavelengths; therefore, it can be used with the laser assembly 10, so that the first laser beam generated by the laser assembly 10 is reflected and does not enter the imaging device, but enters the imaging assembly 30. If it is achieved by other means to meet the functional requirements of avoiding the normal use of the beam imaging device used for autofocus, the dichroic mirror 2021 can also be replaced by other beam splitters.

[0067] The separation and filtering mechanism in the above embodiment not only protects the imaging device from the strong laser beam, but also optimizes the optical path of the beam detection autofocus device, improving the imaging quality and focusing accuracy. The design and use of the dichroic mirror enables the beam detection autofocus device to work efficiently in a complex optical system, ensuring the effective separation and management of the laser focus beam and the imaging beam.

[0068] The embodiment of FIG3 provides another beam detection autofocus device. As shown in FIG3 , the device further includes a lens assembly 50. The lens assembly 50 is disposed between the first beam splitter 201 and the second beam splitter 202. The lens assembly 50 is used to converge the first laser beam.

[0069] When the first laser beam is emitted from the laser assembly 10 and passes through the first beam splitter 201, the lens assembly 50 performs preliminary adjustments on the first laser beam to converge the first laser beam. Specifically, when the first laser beam is emitted from the laser assembly 10 and passes through the first beam splitter 201, the lens assembly 50 performs preliminary adjustments on the first laser beam and converges the first laser beam into an ideal form through appropriate optical design for further processing. The convergence process is used to adjust the intensity and distribution of the first laser beam and correct the directionality of the first laser beam.

[0070] In the above embodiment, the lens assembly enables the first laser beam to be transmitted to the second beam splitter in an optimal form, thereby achieving optimal optical performance. By precisely converging the first laser beam, the lens assembly 50 improves the performance of the entire optical system, so that the first laser beam has good directivity and focusing ability when passing through the second beam splitter 202, thereby improving the accuracy and efficiency of the autofocus system.

[0071] The embodiment of Figure 4 provides another beam detection autofocus device. As shown in Figure 4, the lens assembly 50 includes a concave cylindrical lens 501 and a convex lens 502; the concave cylindrical lens 501 is arranged on a side close to the first beam splitter 201; the convex lens 502 is arranged on a side close to the second beam splitter 202; the concave cylindrical lens 501 is used to direct the long axis of the first laser beam to be incident on the front focal plane of the objective lens as parallel light; the convex lens 502 is used to converge the short axis of the first laser beam at the front focal plane of the objective lens.

[0072] The lens assembly 50 includes a concave cylindrical lens 501 and a convex lens 502, which respectively perform different functions in the optical path. The concave cylindrical lens 501 is arranged on a side close to the first beam splitter 201, and its main function is to adjust the long axis of the first laser beam into a parallel beam so that it remains parallel when it is transmitted to the front focal plane of the objective lens. Specifically, after the first laser beam passes through the concave cylindrical lens 501, the long axis direction of the beam is adjusted to form a parallel beam, so that the first laser beam can remain parallel when entering the front focal plane of the objective lens.

[0073] The convex lens 502 is arranged on a side close to the second beam splitter 202, and is responsible for converging the short axis of the first laser beam. Through the adjustment of the convex lens 502, the short axis of the first laser beam is converged at the front focal plane of the objective lens, so that the first laser beam reaches an ideal focusing state at this point. After the light beam passes through the convex lens 502, the light beam in the short axis direction is converged to the front focal plane of the objective lens, and the best light beam focusing is achieved at this position.

[0074] In some embodiments, in order to achieve the functions of rapid adjustment and adaptation to different working conditions required by the present technical solution, the lens combination should be able to be adjusted separately. After replacing the imaging device of the microscope or changing the working conditions, the position of the lens combination can be adjusted so that the short axis of the light beam converges at the front focal plane of the imaging device objective lens (adjusting the convex lens 502) and the long axis of the light beam is incident on the front focal plane of the imaging device objective lens as parallel light (adjusting the concave cylindrical lens 501).

[0075] In some embodiments, the lens combination that can realize the function of making the long axis and slow axis directions of the elliptical light beam converge to different degrees is not unique, and other different lens combinations can be used as substitutes. The functions that the lens combination needs to realize are: first, the position of the first part of the lens can be adjusted to change the convergence degree of the short axis, and at this time, whether the convergence degree of the long axis will change or not (the function realized by the convex lens 502); then, the position of the second part of the lens can be adjusted to change the convergence degree of the long axis, and at this time, the convergence degree of the short axis will not change (the function realized by the concave cylindrical lens 501).

[0076] In some embodiments, due to the differences in the installation position and working distance of the beam detection autofocus device caused by the mechanical dimensions of different microscope equipment, in actual use, the controller 40 can also be used to adjust the position of the convex lens 502 to converge the first laser beam, thereby enabling the beam detection autofocus device to work normally.

[0077] In the above embodiment, the lens assembly can adjust and converge the long axis and short axis of the laser beam to different degrees, so that the beam has the characteristics of parallel light and convergent light when passing through the front focal plane of the objective lens. The concave cylindrical lens and the convex lens work together in the lens assembly to achieve precise control and adjustment of the long axis and short axis directions of the first laser beam, so that the beam can reach the desired irradiation state on the sample surface.

[0078] The embodiment of FIG5 provides another beam detection autofocus device. As shown in FIG5 , the controller 40 is connected to the concave cylindrical lens 501 ; the controller 40 is also used to adjust the position of the concave cylindrical lens 501 to change the focusing position.

[0079] The controller 40 adjusts the position of the concave cylindrical lens 501, changes the actual focus position of the beam detection autofocus device, and allows it to deviate from the object focal plane of the imaging device of the microscope. This adjustment allows the imaging device of the microscope to focus on the inside of the sample to be tested to observe the characteristics inside the sample. Specifically, the controller 40 moves the position of the concave cylindrical lens 501, thereby changing the convergence point of the short axis of the first laser beam, and the focus of the first laser beam can be adjusted to a position outside the front focal plane of the objective lens, so that the microscope can deeply observe the structure and characteristics inside the sample.

[0080] In the above embodiment, the microscope can flexibly adapt to different imaging requirements, thereby providing detailed observation of the interior of the sample. The controller controls the position adjustment of the concave cylindrical lens so that the first laser beam can be focused on the target position inside the sample, thereby realizing observation of the internal features of the sample.

[0081] The embodiment of Figure 6 provides another beam detection autofocus device. As shown in Figure 6, the laser component 10 includes a laser 101 and a knife-edge aperture 102; the knife-edge aperture 102 is arranged between the laser 101 and the optical component 20; the laser 101 is used to emit an original laser beam; the knife-edge aperture 102 is used to block the long-axis direction of the original laser beam to obtain a first laser beam.

[0082] The laser 101 is used to emit an original laser beam to generate a stable and high-intensity laser source. The original laser beam usually presents an elliptical spot with a distinct major axis and minor axis. In order to optimize the shape of the original laser beam, a knife-edge aperture 102 is disposed between the laser 101 and the optical component 20. The main function of the knife-edge aperture 102 is to block the major axis direction of the original laser beam, thereby adjusting the shape of the original laser beam. Specifically, when the original laser beam passes through the knife-edge aperture 102, the knife-edge aperture 102 will block a portion of the original laser beam in the major axis direction, so that the remaining beam forms a corrected spot, thereby forming a first laser beam.

[0083] In some embodiments, the wavelength of the laser 101 has multiple options. In order to avoid affecting the imaging effect of the imaging device, the laser wavelength is generally selected in the infrared band, and a binocular mirror or an infrared filter is used in the optical path to prevent the light beam used for autofocus from entering the imaging device; when the normal use of the imaging device is met, lasers 101 with other wavelengths can also be used. At the same time, there are multiple options for the type of laser 101: in the example structure, a semiconductor laser 101 is used as the laser 101 of the focusing system, and has an elliptical laser beam shape; but other types of lasers 101 can also be used.

[0084] In some embodiments, the laser 101 does not necessarily need to have an elliptical beam shape; any beam shape having two uniformly symmetrical vertical orthogonal directions and being able to align with the two vertical orthogonal directions of the lens assembly 50 to change the light focusing ability can be sufficient; for example, circular or rectangular beam shapes can meet the requirements.

[0085] In the above embodiment, the knife-edge aperture effectively changes the shape and characteristics of the laser beam, making it more suitable for subsequent optical processing and adjustment. This preliminary beam adjustment lays the foundation for the precise convergence and transmission of the subsequent lens assembly, so that the beam can maintain good shape and directionality throughout the entire optical path, thereby achieving higher autofocus accuracy and effect. The combination of the laser and the knife-edge aperture realizes the optimization adjustment of the original laser beam.

[0086] The embodiment of Figure 7 provides another beam detection autofocus device. As shown in Figure 7, the imaging component 30 includes a converging mirror 301 and a detection charge coupled device 302; the converging mirror 301 is used to converge the third laser beam; the detection charge coupled device 302 is used to generate a focusing signal according to the third laser beam.

[0087] The converging mirror 301 is used to converge the third laser beam returning from the sample. After the third laser beam passes through the dichroic mirror 2021 and the first beam splitter 201, the converging mirror 301 converges the third laser beam and concentrates the scattered beam at one point.

[0088] The detection charge coupled device 302 will receive the third laser beam that has been converged and convert it into an electrical signal. The detection charge coupled device 302 can generate an accurate focus signal based on the intensity and position changes of the beam. Specifically, when the third laser beam is converged onto the detection charge coupled device 302, the light signal detected by the detection charge coupled device 302 will change with the change of the sample position. By analyzing the change of the light signal, the detection charge coupled device 302 can provide information about whether the sample is in focus. The generated focus signal is then transmitted to the controller 40, and the controller 40 makes real-time adjustments based on these signals to achieve precise control of autofocus.

[0089] There is no limitation on the types of the converging mirror 301 and the detection charge coupled device 302. The converging mirror 301 and the detection charge coupled device 302 used in this case are linear array converging mirror 301 and detection charge coupled device 302 modules, but other optical signal detectors, such as planar array converging mirror 301 and detection charge coupled device 302 or two-channel or four-channel photoelectric detectors, can be used as long as they can detect the deviation of the optical signal position.

[0090] In the above embodiment, through the coordinated work of the focusing mirror and the detection charge-coupled device, efficient processing and precise detection of the third laser beam are achieved, so that the imaging component can provide an accurate focusing signal, thereby providing a reliable foundation for the operation of the entire autofocus system.

[0091] In another beam detection autofocus device, as shown in FIG7 , the positions of the above-mentioned converging mirror 301 and the detection charge coupled device 302 should be adjustable, and a certain distance condition should be satisfied between the two, so that after the light beam passes through the converging mirror 301, the long axis direction (the direction in which the parallel light is incident on the front focal plane of the imaging device objective lens) can be converged to the converging mirror 301 and the detection surface of the detection charge coupled device 302. In this way, the proportional relationship between the sample defocus distance and the moving distance of the focusing light intensity signal detected on the converging mirror 301 and the detection charge coupled device 302 can be adjusted, thereby increasing the measurement range of the autofocus system.

[0092] In the above embodiment, by precisely adjusting the distance between the converging mirror and the detection charge coupled device, a higher focusing accuracy can be achieved. The distance between the converging mirror and the detection charge coupled device is not less than a preset value, which can effectively reduce the phenomenon of light beam divergence or excessive convergence caused by too close a distance, so that the light beam converges best on the detector, thereby improving the accuracy of the focusing signal and the imaging clarity.

[0093] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to the memory, database or other medium used in the embodiments provided in the present application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetoresistive random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The database involved in each embodiment provided in this application may include at least one of a relational database and a non-relational database. Non-relational databases may include distributed databases based on blockchains, etc., but are not limited to this. The processor involved in each embodiment provided in this application may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., but are not limited to this.

[0094] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0095] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A beam detection autofocus device, characterized in that: The device comprises a laser component, an optical component, an imaging component and a controller; the controller is connected to the laser component and the imaging component respectively; The laser assembly is used to emit a first laser beam that meets preset conditions; The optical component is used to adjust the first laser beam, and to make the adjusted second laser beam incident on the sample through the objective lens of the microscope, and to transmit the third laser beam returned from the sample to the imaging component; The imaging component is used to generate a focus signal according to the third laser beam; The controller is used to output a control signal according to the focus signal, wherein the control signal is used to control the movement of the objective lens or the stage of the microscope to achieve focusing.

2. The beam detection autofocus device according to claim 1, characterized in that: The optical assembly includes a first beam splitter and a second beam splitter; The first beam splitter is used to transmit the first laser beam to the second beam splitter; The second beam splitter is used to adjust the transmission direction of the first laser beam transmitted by the first beam splitter to obtain the second laser beam, and to adjust the transmission direction of the third laser beam returned from the sample to transmit the third laser beam to the first beam splitter; The first beam splitter is further used to adjust the transmission direction of the third laser beam transmitted by the second beam splitter, so as to transmit the third laser beam to the imaging component.

3. The beam detection autofocus device according to claim 2, characterized in that: The transmittance of the first beam splitter is equal to the reflectivity.

4. The beam detection autofocus device according to claim 2, characterized in that: The second beam splitter is a dichroic mirror; The dichroic mirror is used to block the first laser beam from entering the imaging device of the microscope.

5. The beam detection autofocus device according to claim 2, characterized in that: The device also includes a lens assembly, wherein the lens assembly is disposed between the first beam splitter and the second beam splitter; The lens assembly is used to converge the first laser beam.

6. The beam detection autofocus device according to claim 5, characterized in that: The lens assembly comprises a concave cylindrical lens and a convex lens; the concave cylindrical lens is arranged on a side close to the first beam splitter; the convex lens is arranged on a side close to the second beam splitter; The concave cylindrical lens is used to direct the long axis of the first laser beam to be incident on the front focal plane of the objective lens as parallel light; The convex lens is used to converge the short axis of the first laser beam at the front focal plane of the objective lens.

7. The beam detection autofocus device according to claim 6, characterized in that: The controller is connected to the concave cylindrical lens; The controller is also used to adjust the position of the concave cylindrical lens to change the focusing position.

8. The beam detection autofocus device according to claim 1, characterized in that: The laser assembly comprises a laser and a knife-edge aperture; the knife-edge aperture is arranged between the laser and the optical assembly; The laser is used to emit an original laser beam; The knife-edge aperture is used to block the long-axis direction of the original laser beam to obtain the first laser beam.

9. The beam detection autofocus device according to claim 1, characterized in that: The imaging assembly includes a focusing mirror and a detection charge coupled device; The converging mirror is used to converge the third laser beam; The detection charge coupled device is used to generate the focus signal according to the third laser beam.

10. The beam detection autofocus device according to claim 9, characterized in that: The position between the converging mirror and the detection charge coupled device is adjustable, and the distance between the converging mirror and the detection charge coupled device is not less than a preset value.

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