A microfluidic chip imaging and positioning device and imaging and positioning method

Abstract

This invention discloses a microfluidic chip imaging and positioning device and method, belonging to the field of microfluidic chip positioning technology. The technical solution includes: taking a picture of the microfluidic chip using a macroscopic camera and performing distortion correction; identifying the microfluidic chip's marker points or channels based on a microfluidic chip marker point or channel recognition model; performing coordinate transformation based on a calibration matrix to obtain the set of pixel coordinates in the microscopic camera coordinates, which is the positioning coordinate set of the microfluidic chip; and obtaining the coordinates of any position of the microfluidic chip from the positioning coordinate set, thus completing the imaging and positioning of the microfluidic chip. This invention is applied to microfluidic chip imaging and positioning, solving the drawbacks of existing microfluidic chip fixtures and addressing the technical problems of universality, automation, and high precision in microfluidic chip positioning. It features speed, automation, high precision, and universality.

Description

Technical Field

[0001] This invention belongs to the field of microfluidic chip positioning technology, and particularly relates to a microfluidic chip imaging positioning device and imaging positioning method. Background Technology

[0002] Microfluidic chip technology plays a vital role in fields such as chemistry, medicine, and biology due to its advantages of small size, low sample volume, low contamination, and high efficiency. In the field of biology, microscopic observation or detection of biological samples within microfluidic chips is often required, making chip fixation and positioning crucial. Currently, the common approach is to design microfluidic chip fixtures or sleeves tailored to the specific chip structure. Positioning is achieved through holes or edges in the fixture, and clamping force is provided by flexible materials on the fixture (typically elastic sealing rings or flexible gaskets) to create a tight seal. The fixture or sleeve is then fixed to the observation platform.

[0003] Chinese patent CN201320465462.1 discloses a rapid positioning device for microfluidic chips. The main components consist of a three-dimensional platform and a positioning sleeve. The microfluidic chip is inserted into and secured in the positioning sleeve, which is fixed to a three-dimensional translation stage. The position of the microfluidic chip can be adjusted by controlling the movement of the three-dimensional platform. The advantages of this method are its ease of use and rapid positioning.

[0004] However, the methods disclosed in the aforementioned patents have certain limitations. Specifically: First, the design and adjustment precision requirements of the fixture are high. For soft materials such as PDMS chips, excessive clamping force will cause severe chip deformation, leading to blockage of the microfluidic channels. Insufficient clamping force will cause chip leakage. For hard materials such as glass chips, repeated contact with the fixture will cause small glass shards to accumulate in the fixture, affecting positioning accuracy. At the same time, to adapt to the fixture, high processing precision is required for different batches of the same type of chip. Second, different biological samples require the use of microfluidic chips with different structures, but the fixture needs to be designed for each fixed model of microfluidic chip, lacking universality, thus resulting in low efficiency and high cost. Third, chip replacement involves positioning and clamping, requiring manual operation, which cannot be automated. Finally, the above positioning method also involves the coupling between the chip fixture and the observation platform. Due to the influence of structural precision, there will be a slight positional difference each time it is placed, resulting in significant uncertainty. Summary of the Invention

[0005] Details of one or more embodiments of the present invention are set forth in the following drawings and description to make other features, objects and advantages of the present application more readily apparent.

[0006] This invention proposes a microfluidic chip imaging and positioning device and method, which solves the drawbacks of existing microfluidic chip fixtures and addresses the technical problems of universality, automation, and high precision in microfluidic chip positioning. It features speed, automation, high precision, and universality.

[0007] This invention discloses a microfluidic chip imaging and positioning method, comprising the following steps:

[0008] A macroscopic camera was used to photograph the microfluidic chip, and distortion correction was performed.

[0009] The microfluidic chip is identified by identifying its marker points or channels based on a microfluidic chip marker point or channel identification model.

[0010] The set of pixel coordinates in the micro-camera coordinates is obtained by performing coordinate transformation based on the calibration matrix, which is the positioning coordinate set of the microfluidic chip;

[0011] The coordinates of any position of the microfluidic chip can be obtained from the positioning coordinate set, thus completing the imaging and positioning of the microfluidic chip;

[0012] The calibration matrix and the microfluidic chip marker or channel identification model are established using the following methods:

[0013] Place the distortion correction plate, take a picture of the distortion correction plate with a macro camera, and calculate the distortion correction matrix M0 of the macro camera based on the picture;

[0014] After verifying that the distortion correction residual meets the requirements, a macro calibration plate is placed, a macro camera takes a picture of the macro calibration plate, the distortion of the picture is corrected according to M0, and then N-point calibration is performed to obtain the transformation matrix M1 between the macro camera coordinates and the three-dimensional platform coordinates.

[0015] After verifying that the error between the measured and predicted values ​​meets the requirements, a micro calibration plate is placed, and a micro camera takes a picture of the calibration plate. Based on the picture, N-point calibration is performed to obtain the transformation matrix M2 between the three-dimensional platform coordinates and the micro camera coordinates.

[0016] After verifying that the error between the measured and predicted values ​​meets the requirements, the microfluidic chip is placed and photographed with a macro camera. This batch of photographs serves as the training set for chip recognition. Distortion correction is performed on the training set for chip recognition based on M0, and a microfluidic chip marker or channel recognition model is established based on a deep learning algorithm.

[0017] Another aspect of the present invention discloses a microfluidic chip imaging and positioning device for the aforementioned microfluidic chip imaging and positioning method, comprising a micro-illumination module, a micro-imaging module, a chip movement and macro-illumination module, a macro-imaging module, and an optical path multiplexing module; the micro-illumination module includes a compound eye lens assembly, which comprises two compound eye lenses, the optical axes of the two compound eye lenses are parallel to each other, and the focal point of each lens array element in one compound eye lens coincides with the center of the corresponding lens array element in the other compound eye lens; the micro-imaging module is used to perform infinity microscopic imaging of the sample, providing visualization of the sample morphology and spatial position; the chip movement and macro-illumination module scans and moves the microfluidic chip and provides bright-field illumination for macro-imaging; the macro-imaging module performs macro-visual imaging of the entire chip for positioning; and the optical path multiplexing module combines the micro-illumination module and the macro-imaging module.

[0018] In some embodiments, the chip movement and macroscopic illumination module further includes: a three-dimensional motorized scanning platform, a macroscopic light source, and a microfluidic chip holder; the three-dimensional motorized scanning platform moves in the XY direction to move the microfluidic chip back and forth and left and right for scanning, and moves in the Z direction to perform microscopic focusing on the microfluidic chip; the macroscopic light source provides lateral illumination to the microfluidic chip; the microfluidic chip holder is fixed on the three-dimensional motorized scanning platform, and the microfluidic chip holder has a placement area for placing the microfluidic chip; the macroscopic light source is fixed on the microfluidic chip holder and distributed along the circumference of the microfluidic chip.

[0019] In some embodiments, the microfluidic chip support further includes: a support body, a placement area, and a light board; the support body is fixedly connected to a three-dimensional electric scanning platform; the placement area is formed on the support body, and the microfluidic chip is fixed in the placement area; the light board is fixedly connected to the support body and is distributed along the circumference of the placement area; the macroscopic light source is a plurality of white LEDs, and the plurality of white LEDs are uniformly fixed on the light board along the circumference of the placement area.

[0020] In some embodiments, the microfluidic chip holder also includes a lamp board cover that is fixedly connected to and detachably disposed above a plurality of white LEDs.

[0021] In some embodiments, the light panel is a split structure, including a first light panel disposed on one side of the placement area and a second light panel disposed on the other side of the placement area; the light panel cover includes a first light panel cover fixedly connected to the first light panel and a second light panel cover fixedly connected to the second light panel.

[0022] In some embodiments, the micro-illumination module further includes: a micro-light source, a collimating mirror that collimates the diverging light of the micro-light source into parallel light, a reflecting mirror that bends the light path by 90° to compress the volume of the light path, and a condenser mirror.

[0023] In some embodiments, the microscopic imaging module includes: a microscope objective, a microscopic imaging lens assembly that focuses a sample image onto a microscopic camera, and a microscopic camera that receives imaging signals; the macroscopic imaging module includes: a visual imaging lens assembly that focuses a microfluidic chip image onto a macroscopic camera, and a macroscopic camera that receives microfluidic chip imaging signals.

[0024] In some embodiments, the optical path multiplexing module further includes: a condenser lens, a condenser lens switching component, and a beam splitter; the condenser lens switching component fixes the condenser lens and controls the condenser lens to be located at a first position entering the optical path or a second position cutting out the optical path; when the condenser lens is located at the first position, the condenser lens is located above the microfluidic chip, the condenser lens and the main ray of the micro-illumination module are coaxial, and the macroscopic imaging module does not work; when the condenser lens is located at the second position, the macroscopic imaging module performs macroscopic imaging on the microfluidic chip, and the micro-illumination module does not work; the beam splitter is located above the first position, the light from the micro-illumination module is transmitted through the beam splitter, and the light reflected back from the microfluidic chip illuminated by the macroscopic light source is reflected through the beam splitter and enters the visual imaging lens assembly.

[0025] In some embodiments, the microfluidic chip imaging and positioning device further includes a computer control system, which is electrically connected to a micro-illumination module, a micro-imaging module, a chip movement and macro-illumination module, a macro-imaging module, and an optical path multiplexing module.

[0026] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0027] This invention provides a microfluidic chip imaging and positioning method and a microfluidic chip imaging and positioning device, which can completely replace the traditional positioning scheme based on chip fixtures. Its advantages are specifically reflected in:

[0028] 1. It has strong versatility and does not require separate design for microfluidic chips with different structures. First, it is applicable to microfluidic chips with different internal structures such as liquid channels and gas channels. Second, as long as the appearance size of the microfluidic chip within the detection field of view of the macroscopic imaging module is met, it can be directly detected. It has strong versatility, which not only avoids the disadvantages of high design and debugging accuracy of fixtures, but also reduces the chip accuracy requirements, thereby reducing costs and improving detection efficiency.

[0029] 2. Increased automation: This device solves the problem that chip fixtures cannot be automated due to positioning and clamping. Through the design of chip bracket structure and common optical path coupling, it reserves the operating space for automated equipment, which can realize fully unattended automated positioning and detection.

[0030] 3. Fast and high precision: This device is based on visual imaging positioning, which avoids the chip fixture loading process. Chip positioning can be completed in seconds, improving efficiency by more than ten times. Based on a high-resolution macro camera, combined with deep learning algorithm modeling and recognition positioning, the positioning accuracy can reach 1μm, which is significantly improved compared to the mechanical positioning error of 10-100μm. Attached Figure Description

[0031] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this invention, illustrate exemplary embodiments of the invention and are used to explain the invention, but do not constitute an undue limitation of the invention. In the drawings:

[0032] Figure 1 This is a schematic diagram of the microfluidic chip imaging and positioning device provided in an embodiment of the present invention;

[0033] Figure 2 This is a schematic diagram of the microfluidic chip support structure provided in an embodiment of the present invention;

[0034] Figure 3 This is a schematic diagram of the compound eye lens assembly provided in an embodiment of the present invention;

[0035] Figure 4 This is a schematic diagram of the microfluidic chip visual imaging and positioning process provided in an embodiment of the present invention;

[0036] Figure 5 This is a schematic diagram illustrating the process of establishing a microfluidic chip marker or channel recognition model provided in an embodiment of the present invention.

[0037] Figure 6 This is a schematic diagram of the macroscopic light source arrangement on the lamp board provided in an embodiment of the present invention;

[0038] Figure 7 This is a simulated image of the illumination spot at the sample provided in an embodiment of the present invention;

[0039] Figure 8 This is an imaging effect diagram of a microfluidic chip provided in an embodiment of the present invention;

[0040] Figure descriptions: 101. Compound eye lens assembly; 102. Microscopic sight source; 103. Collimating lens; 104. Reflecting mirror; 105. Condensing lens; 201. Three-dimensional motorized scanning platform; 202. Macroscopic light source;

[0041] 2031. Support body; 2032. Light panel; 2033. Light panel cover;

[0042] 301. Microscope objective lens; 302. Microscopic imaging lens assembly; 303. Microscopic camera; 401. Visual imaging lens assembly; 402. Macroscopic camera; 501. Condenser lens switching assembly; 502. Beam splitter prism; 60. Computer control system; 70. Microfluidic chip. Detailed Implementation

[0043] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be described and illustrated below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. All other embodiments obtained by those skilled in the art based on the embodiments provided by this invention without inventive effort are within the scope of protection of this invention.

[0044] Obviously, the accompanying drawings described below are merely some examples or embodiments of the present invention. Those skilled in the art can apply the present invention to other similar scenarios based on these drawings without any inventive effort. Furthermore, it is understood that although the efforts made in this development process may be complex and lengthy, for those skilled in the art related to the content disclosed in this invention, modifications to design, manufacturing, or production based on the technical content disclosed in this invention are merely conventional technical means and should not be construed as insufficient disclosure of the present invention.

[0045] In this invention, the reference to "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the invention. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described in this invention may be combined with other embodiments without conflict.

[0046] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "a," "an," "an," "the," and similar words used in this invention do not indicate quantity limitation and may indicate singular or plural. The terms "comprising," "including," "having," and any variations thereof used in this invention are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or device that includes a series of steps or modules (units) is not limited to the listed steps or units, but may also include steps or units not listed, or may include other steps or units inherent to these processes, methods, products, or devices. The terms "connected," "linked," "coupled," and similar words used in this invention are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "A plurality" in this invention refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships may exist; for example, "A and / or B" can represent: A alone, A and B simultaneously, and B alone. The character " / " generally indicates that the preceding and following objects have an "or" relationship. The terms "first," "second," and "third" used in this invention are merely to distinguish similar objects and do not represent a specific ordering of the objects.

[0047] This invention discloses, in one aspect, an imaging and positioning method for a microfluidic chip 70, such as... Figure 4 As shown, it includes the following steps:

[0048] A macroscopic camera 402 was used to take a picture of the microfluidic chip 70, and distortion correction was performed.

[0049] The microfluidic chip 70 is identified by its marker points or channels based on the marker point or channel identification model.

[0050] The set of pixel coordinates in the coordinate system of the micro-camera 303 is obtained by performing coordinate transformation based on the calibration matrix, which is the positioning coordinate set of the microfluidic chip 70.

[0051] The coordinates of any position of the microfluidic chip 70 can be obtained from the positioning coordinate set, thus completing the imaging positioning of the microfluidic chip 70.

[0052] like Figure 5 As shown, the calibration matrix and the microfluidic chip 70 marker point or channel recognition model are established using the following method:

[0053] Place the distortion correction plate, take a picture of the distortion correction plate with the macro camera 402, and calculate the distortion correction matrix M0 of the macro camera 402 based on the picture;

[0054] After verifying that the distortion correction residual meets the requirements, a macro calibration plate is placed, and a macro camera 402 takes a picture of the macro calibration plate. The distortion of the picture is corrected according to M0, and then N-point calibration is performed to obtain the transformation matrix M1 of the coordinates of the macro camera 402 and the coordinates of the three-dimensional platform.

[0055] After verifying that the error between the measured and predicted values ​​meets the requirements, a micro calibration plate is placed, and the micro camera 303 takes a picture of the calibration plate. Based on the picture, N-point calibration is performed to obtain the transformation matrix M2 between the coordinates of the three-dimensional platform and the coordinates of the micro camera 303.

[0056] After verifying that the error between the measured and predicted values ​​meets the requirements, the microfluidic chip 70 is placed and a macroscopic camera 402 is used to take pictures of the microfluidic chip 70. This batch of pictures is used as the training set for chip recognition. The distortion of the training set for chip recognition is corrected according to M0, and a microfluidic chip 70 marker point or channel recognition model is established based on deep learning algorithm.

[0057] The aforementioned imaging and positioning method first requires calibration and modeling. Specifically, this includes: 1. Calibrating the coordinate transformation relationship between the macroscopic camera 402 and the microscopic camera 303 relative to the 3D motorized scanning platform 201; 2. Due to the large field of view of the macroscopic camera 402, distortion correction calibration of the macroscopic camera 402 is required; 3. To identify the chip for easier positioning, a recognition model of chip marker points or channels needs to be established based on deep learning algorithms. The specific process is as follows... Figure 5 As shown. This calibration and modeling work is performed after the device is assembled and adjusted, and only needs to be done once. It is directly built into the host computer software on the computer control system 60 and does not need to be updated with different microfluidic chips 70.

[0058] After calibration and model building, the microfluidic chip 70 can be visually imaged and positioned using the aforementioned device. This includes: 1. Taking a picture of the chip with the macro camera 402 and performing distortion correction; 2. Identifying marker points or channels on the chip based on the model; 3. Performing coordinate transformation based on the calibration matrix to obtain the set of pixel coordinates in the coordinate system of the micro camera 303, which is the chip's positioning coordinate set; 4. Obtaining the coordinates of any position on the chip from the positioning coordinate set, facilitating imaging, identification, detection, and scanning of samples within the chip. The specific process is as follows: Figure 4 As shown.

[0059] Another aspect of the present invention discloses a microfluidic chip 70 imaging and positioning device for the above-described microfluidic chip 70 imaging and positioning method, such as... Figure 1 As shown, it includes a microscopic illumination module, a microscopic imaging module, a chip movement and macroscopic illumination module, a macroscopic imaging module, and an optical path multiplexing module; the microscopic illumination module includes a compound eye lens assembly 101, as shown... Figure 3As shown, the compound eye lens assembly 101 includes two compound eye lenses with parallel optical axes. The focal points of each lens array element in one compound eye lens coincide with the center of the corresponding lens array element in the other compound eye lens. The microscopic imaging module is used to perform infinity microscopic imaging of the sample, providing visualization of the sample morphology and spatial position. The chip movement and macroscopic illumination module scans and moves the microfluidic chip 70 and provides bright-field illumination for macroscopic imaging. The macroscopic imaging module performs macroscopic visual imaging of the entire chip for positioning. In some embodiments, the microscopic illumination module further includes: a microscopic light source 102, a collimating mirror 103 that collimates the diverging light of the microscopic light source 102 into parallel light, a reflecting mirror 104 that bends the optical path by 90° to compress the optical path volume, and a condenser lens 105. The optical path multiplexing module is used to organically combine the microscopic illumination module and the macroscopic imaging module.

[0060] Regarding the microscopic illumination module, it should be noted that it provides suitable bright-field illumination for microscopic imaging. It includes a microscopic light source 102, which provides the light source for bright-field microscopic imaging; the microscopic light source 102 can be a white LED or a halogen lamp, etc.; a collimating lens 103, which collimates the divergent light from the light source into parallel light; a compound eye lens assembly 101, containing two compound eye lenses with identical parameters, which improves the uniformity and brightness of the illumination; a reflecting mirror 104, which bends the light path by 90° to compress the light path volume; and a condenser lens 105, which focuses the light from the compound eye lens assembly 101 into a uniform square spot to illuminate the sample area. The microscopic illumination module is one of the core modules of this device, and its main function is to provide high light energy utilization and high uniformity illumination for microscopic imaging. The compound eye lens assembly 101 is key to achieving the above effects. The optical axes of the two compound eye lenses it contains are parallel to each other, and the focal points of each lens array element in the first compound eye lens coincide with the centers of the corresponding lens array elements in the second compound eye lens. The external structure of the compound eye lens is as follows: Figure 3As shown. When the microscopic illumination module is working normally, the light emitted by the microscopic light source 102 is collimated into parallel light by the collimating lens 103. This parallel light is then focused onto the center of the corresponding lens array element of the second compound eye lens after passing through the lens array elements of the first compound eye lens. The first compound eye lens divides the wide illumination beam into multiple narrow illumination beams. The uniformity within each narrow beam is necessarily greatly enhanced. Due to the uniformity of the single illumination range of the wide beam, and because the entire system is a rotationally symmetric system, the slight non-uniformities at the edges of each narrow beam are compensated for by the superposition of symmetrical positions, further improving the uniformity of illumination and enabling the light energy within the entire aperture to be effectively and uniformly utilized. The second compound eye lens acts as a field mirror. The light spot emitted from it is then focused onto the sample by the condenser lens 105. Each small focused light spot on the sample is illuminated by light emitted from all points of the light source. At the same time, the light beams emitted from each point of the light source overlap and converge into the same field of view on the illumination spot. Therefore, all the small light spots converge to form a uniform square light spot, illuminating the sample area, as shown. Figure 7 As shown.

[0061] In some embodiments, the chip movement and macroscopic illumination module further includes: a three-dimensional motorized scanning platform 201, a macroscopic light source 202, and a microfluidic chip 70 support; the three-dimensional motorized scanning platform 201 moves in the XY direction to move the microfluidic chip 70 back and forth and left and right for scanning, and moves in the Z direction to perform microscopic focusing on the microfluidic chip 70; the macroscopic light source 202 provides lateral illumination to the microfluidic chip 70; the microfluidic chip 70 support is fixed on the three-dimensional motorized scanning platform 201, and the microfluidic chip 70 support has a placement area for placing the microfluidic chip 70; the macroscopic light source 202 is fixed on the microfluidic chip 70 support and distributed circumferentially along the microfluidic chip 70. Figure 2 As shown, the microfluidic chip 70 support further includes: a support body 2031, a placement area, and a light board 2032; the support body 2031 is fixedly connected to the three-dimensional motorized scanning platform 201; the placement area is formed on the support body 2031, and the microfluidic chip 70 is fixed in the placement area; the light board 2032 is fixedly connected to the support body 2031 and is distributed circumferentially along the placement area; the macroscopic light source 202 is a plurality of white LEDs, such as... Figure 6 As shown, several white LEDs are uniformly fixed on the lamp board 2032 along the circumference of the placement area.

[0062] The chip movement and macroscopic illumination module is designed to scan and move the chip, providing suitable bright-field illumination for macroscopic imaging. It includes a 3D motorized scanning platform 201, which uses a DC motor to move the microfluidic chip 70 with high precision. Movement in the XY directions moves the chip forward, backward, left, and right for scanning, while movement in the Z direction allows for microscopic focusing. The platform's accuracy and resolution can be configured according to requirements; in this embodiment, the minimum step size is 20nm, and the repeatability during movement is 0.5μm. A macroscopic light source 202 provides the light source for macroscopic bright-field imaging. The macroscopic light source 202 consists of a series of LEDs evenly distributed around the microfluidic chip 70, providing lateral illumination. A microfluidic chip 70 support is used to fix the macroscopic light source 202 and provide a placement area for the chip. The biggest challenge in macroscopic visual imaging and positioning of the microfluidic chip 70 is that the microfluidic chip 70 is generally made of a completely transparent material, and to ensure microscopic imaging effects, its material has high light transmittance. When imaging the chip with ordinary coaxial or transmitted illumination, most of the light is transmitted or scattered, and the background causes great interference, making it impossible to see the fine structure of the internal channels of the chip clearly. Even the external outline cannot be clearly distinguished from the background. Therefore, this invention proposes an integrated microfluidic chip 70 support design based on lateral illumination, the structure of which is as follows: Figure 2 As shown, it includes a support body 2031, a first lamp plate 2032, a second lamp plate 2032, a first lamp plate cover 2033, and a second lamp plate cover 2033. The support body 2031 is fastened to the 3D electric scanning platform 201 with screws and serves as a carrier for the chip and macroscopic lateral illumination source. Space is reserved at the upper and lower structures to facilitate the mechanical gripper's gripping and placement of the chip, achieving full automation. The structures of the first and second lamp plates 2032 are as follows: Figure 6 As shown, several white LEDs are symmetrically distributed on it to uniformly illuminate the microfluidic chip 70 from the side. The first lamp plate cover 2033 and the second lamp plate cover 2033 respectively isolate and protect the lamp plate 2032 and enhance its aesthetics. This integrated microfluidic chip 70 support structure is simple, small in size, and easy to use. It can meet the needs of automated operation and has strong versatility. Taking a microfluidic chip 70 sample as an example, the imaging effect is as follows: Figure 8 As shown, the channels and markers in the microfluidic chip 70 are clearly imaged with high contrast to the background.

[0063] In some embodiments, the microfluidic chip 70 support also includes a lamp board cover 2033 that is disposed above a plurality of white LEDs and is detachably and fixedly connected to the lamp board 2032.

[0064] In some embodiments, the lamp panel 2032 is a split structure, including a first lamp panel 2032 disposed on one side of the placement area and a second lamp panel 2032 disposed on the other side of the placement area; the lamp panel cover 2033 includes a first lamp panel cover 2033 fixedly connected to the first lamp panel 2032 and a second lamp panel cover 2033 fixedly connected to the second lamp panel 2032.

[0065] In some embodiments, the microscopic imaging module includes: a microscope objective 301, a microscope imaging lens assembly 302 that focuses the sample image onto a microscopic camera 303, and a microscopic camera 303 that receives the imaging signal. The microscopic imaging module performs infinity-corrected microscopic imaging of the sample, providing visualization of the sample's morphology and spatial location. It includes the microscope objective 301, which performs microscopic magnification imaging and is characterized by high magnification (≥50X), high NA (≥0.8), ultra-flat field, and apochromatic; the microscope imaging lens assembly 302, which focuses the sample image onto the microscopic camera 303 and is characterized by wide-field imaging, apochromatic, and diffraction-limited performance across the entire field of view; and the microscopic camera 303, which receives the imaging signal and whose resolution and field of view parameters can be configured as needed.

[0066] In some embodiments, the macroscopic imaging module includes: a visual imaging lens assembly 401 that focuses an image of the microfluidic chip 70 onto a macroscopic camera 402, and a macroscopic camera 402 that receives imaging signals from the microfluidic chip 70. The macroscopic imaging module performs macroscopic visual imaging of the entire chip for positioning. It includes the visual imaging lens assembly 401, which focuses the chip image onto the macroscopic camera 402. Its features include a large field of view (covering the entire size of the chip) and a long working distance (facilitating common optical path coupling with the micro-illumination module); and the macroscopic camera 402, which receives the chip imaging signal. Its features include high resolution (20 megapixels and above) for clear imaging of the micro-channels of the microfluidic chip 70 and a large field of view for clear imaging of the entire chip field of view.

[0067] In some embodiments, the optical path multiplexing module organically combines the micro-illumination module and the macro-imaging module, and further includes: a condenser lens 105, a condenser lens switching component 501, and a beam splitter 502; the condenser lens switching component 501 fixes the condenser lens 105 and controls the condenser lens 105 to be located at a first position entering the optical path or a second position cutting out the optical path; when the condenser lens 105 is located at the first position, the condenser lens 105 is located above the microfluidic chip 70, the condenser lens 105 and the main ray of the micro-illumination module are coaxial, and the macro-imaging module does not work; when the condenser lens 105 is located at the second position, the macro-imaging module performs macro-imaging on the microfluidic chip 70, and the micro-illumination module does not work; the beam splitter 502 is located above the first position, the light from the micro-illumination module is transmitted through the beam splitter 502, and the light reflected back from the microfluidic chip 70 illuminated by the macro-light source 202 is reflected through the beam splitter 502 and enters the visual imaging lens assembly 401.

[0068] The optical path multiplexing module combines the micro-illumination module and the macro-imaging module to achieve optical path multiplexing. This common optical path design greatly reduces the size and complexity of the overall device and can realize the functions of the two modules without moving the chip, thus improving efficiency. This module includes a beam splitter 502, which allows light from the micro-illumination module to be transmitted so that it can be focused into a uniform square spot by the condenser lens 105 to illuminate the sample area. Simultaneously, it allows light reflected from the chip illuminated by the macro-light source 202 to be reflected into the vision imaging lens assembly 401. This assembly can also be replaced by other beam splitters such as a flat beam splitter or a thin-film beam splitter. A condenser lens switching assembly 501 is also included, with the condenser lens 105 fixed to it via a flange. This assembly controls the condenser lens 105's entry into and exit from the optical path. When entering the optical path, the condenser lens 105 and the main ray from the micro-illumination module are coaxial, forming a micro-illumination spot, and the macro-imaging module is not activated. When exiting the optical path, the macro-imaging module performs macroscopic imaging of the chip, and the micro-illumination module is not activated. Furthermore, when the condenser lens 105 exits the optical path, the area above the microfluidic chip 70 becomes larger, facilitating the mechanical gripper to pick up and place the chip, thus achieving full automation. The condenser lens switching component 501 can be implemented through a linear motor module, an angle deflection module, or a magnetic encoder servo motor.

[0069] In some embodiments, the microfluidic chip 70 imaging and positioning device further includes a computer control system 60, which is electrically connected to a micro-illumination module, a micro-imaging module, a chip movement and macro-illumination module, a macro-imaging module, and an optical path multiplexing module.

[0070] The computer control system 60 serves as the control and display center for the entire device. It can issue control commands and processes via host computer software, specifically including controlling the switching and brightness of the microscopic light source 102 and the macroscopic light source 202; controlling the speed, direction, step value, and distance parameters of the three-dimensional motorized scanning platform 201; controlling the condenser lens switching component 501, thereby controlling the condenser lens 105 entering and exiting the light path; and controlling the exposure time and white balance parameters of the microscopic camera 303 and the macroscopic camera 402. Additionally, this system is responsible for displaying the sample and chip image planes, and for locating the microfluidic chip 70 and measuring the sample within the chip via the built-in microfluidic chip in the host computer software.

[0071] The aforementioned microfluidic chip 70 imaging positioning method and microfluidic chip 70 imaging positioning device can completely replace the traditional positioning scheme based on chip fixtures. Its advantages are specifically reflected in:

[0072] 1. It has strong versatility and does not require separate design for microfluidic chips 70 with different structures. First, it is applicable to microfluidic chips 70 with different internal structures such as liquid channels and gas channels. Second, as long as the appearance size of the microfluidic chip 70 within the detection field of view of the macroscopic imaging module is met, it can be directly detected. It has strong versatility, which not only avoids the disadvantages of high design and debugging accuracy of fixtures, but also reduces the chip accuracy requirements, thereby reducing costs and improving detection efficiency.

[0073] 2. Increased automation: This device solves the problem that chip fixtures cannot be automated due to positioning and clamping. Through the design of chip bracket structure and common optical path coupling, it reserves the operating space for automated equipment, which can realize fully unattended automated positioning and detection.

[0074] 3. Fast and high precision: This device is based on visual imaging positioning, which avoids the chip fixture loading process. Chip positioning can be completed in seconds, improving efficiency by more than ten times. Based on the high-resolution macro camera 402, combined with deep learning algorithm modeling and recognition positioning, the positioning accuracy can reach 1μm, which is significantly improved compared to the mechanical positioning error of 10-100μm.

[0075] The technical features of the above embodiments can be combined in any way. For the sake of brevity, 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.

[0076] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A microfluidic chip imaging and positioning method, characterized in that, Includes the following steps: A macroscopic camera was used to photograph the microfluidic chip, and distortion correction was performed. The microfluidic chip is identified by identifying its marker points or channels based on a microfluidic chip marker point or channel identification model. The set of pixel coordinates in the micro-camera coordinates is obtained by performing coordinate transformation based on the calibration matrix, which is the positioning coordinate set of the microfluidic chip; The coordinates of any position of the microfluidic chip can be obtained from the positioning coordinate set, thus completing the imaging and positioning of the microfluidic chip; The calibration matrix and the microfluidic chip marker or channel identification model are established using the following methods: Place the distortion correction plate, take a picture of the distortion correction plate with a macro camera, and calculate the distortion correction matrix M0 of the macro camera based on the picture; After verifying that the distortion correction residual meets the requirements, a macro calibration plate is placed, a macro camera takes a picture of the macro calibration plate, the distortion of the picture is corrected according to M0, and then N-point calibration is performed to obtain the transformation matrix M1 between the macro camera coordinates and the three-dimensional platform coordinates. After verifying that the error between the measured and predicted values ​​meets the requirements, a micro calibration plate is placed, and a micro camera takes a picture of the calibration plate. Based on the picture, N-point calibration is performed to obtain the transformation matrix M2 between the three-dimensional platform coordinates and the micro camera coordinates. After verifying that the error between the measured and predicted values ​​meets the requirements, the microfluidic chip is placed and photographed with a macro camera. This batch of photographs serves as the training set for chip recognition. Distortion correction is performed on the training set for chip recognition based on M0, and a microfluidic chip marker or channel recognition model is established based on a deep learning algorithm.

2. A microfluidic chip imaging and positioning device for the microfluidic chip imaging and positioning method according to claim 1, characterized in that, include The micro-illumination module includes a compound eye lens assembly, which includes two compound eye lenses. The optical axes of the two compound eye lenses are parallel to each other, and the focal point of each lens array element in one compound eye lens coincides with the center of the corresponding lens array element in the other compound eye lens. The microscopic imaging module is used to perform infinity-scale microscopic imaging of samples, providing visualization of sample morphology and spatial location; The chip movement and macroscopic illumination module scans and moves the microfluidic chip and provides bright-field illumination for macroscopic imaging; The macroscopic imaging module performs macroscopic visual imaging of the entire chip for positioning. And an optical path multiplexing module, which combines the micro-illumination module with the macro-imaging module.

3. The microfluidic chip imaging and positioning device according to claim 2, characterized in that, The chip movement and macro lighting module further includes: The three-dimensional electric scanning platform moves in the XY direction to move the microfluidic chip back and forth and left and right to perform scanning, and moves in the Z direction to perform microscopic focusing on the microfluidic chip. Macroscopic light source provides lateral illumination to the microfluidic chip; A microfluidic chip holder is fixed on a three-dimensional motorized scanning platform. The microfluidic chip holder has a placement area for placing the microfluidic chip. A macroscopic light source is fixed on the microfluidic chip holder and distributed around the microfluidic chip.

4. The microfluidic chip imaging and positioning device according to claim 3, characterized in that, The microfluidic chip scaffold further includes: The main support frame is fixedly connected to the 3D electric scanning platform. The placement area is located on the main body of the support, and the microfluidic chip is fixed in the placement area. The light panel is fixedly connected to the main body of the bracket and is distributed circumferentially along the placement area; The macroscopic light source is a number of white LEDs, which are uniformly fixed on the lamp board along the circumference of the placement area.

5. The microfluidic chip imaging and positioning device according to claim 4, characterized in that, The microfluidic chip support also includes a lamp board cover that is fixedly connected to several white LEDs and is detachably mounted on the lamp board.

6. The microfluidic chip imaging and positioning device according to claim 5, characterized in that, The light panel has a split structure, including a first light panel located on one side of the placement area and a second light panel located on the other side of the placement area; the light panel cover includes a first light panel cover fixedly connected to the first light panel and a second light panel cover fixedly connected to the second light panel.

7. The microfluidic chip imaging and positioning device according to claim 2, characterized in that, The micro-illumination module further includes: a micro-light source, a collimating mirror that collimates the diverging light of the micro-light source into parallel light, a reflecting mirror that bends the light path by 90° to compress the volume of the light path, and a condenser lens.

8. The microfluidic chip imaging and positioning device according to claim 2, characterized in that, The microscopic imaging module includes: a microscope objective, a microscopic imaging lens assembly that focuses sample images onto a microscopic camera, and a microscopic camera that receives imaging signals; the macroscopic imaging module includes: a visual imaging lens assembly that focuses microfluidic chip images onto a macroscopic camera, and a macroscopic camera that receives microfluidic chip imaging signals.

9. The microfluidic chip imaging and positioning device according to claim 7, characterized in that, The optical path multiplexing module further includes: A condenser lens switching component fixes the condenser lens and controls it to be in either the first position entering the optical path or the second position cutting out the optical path. When the condenser lens is in the first position, it is positioned above the microfluidic chip, and the condenser lens and the main ray of the micro-illumination module are coaxial, while the macroscopic imaging module is not in operation. When the condenser lens is in the second position, the macroscopic imaging module performs macroscopic imaging of the microfluidic chip, while the micro-illumination module is not in operation. The beam splitter, located above the first position, is a light-transmitting beam splitter of the micro-illumination module. The light reflected back from the microfluidic chip illuminated by the macro-light source is reflected through the beam splitter and enters the visual imaging lens assembly.

10. The microfluidic chip imaging and positioning device according to claim 9, characterized in that, The microfluidic chip imaging and positioning device also includes a computer control system, which is electrically connected to the micro-illumination module, the micro-imaging module, the chip movement and macro-illumination module, the macro-imaging module, and the optical path multiplexing module.

Images