Photoelectric microfluidic method for automatically generating liquid drops as required

Abstract

The invention discloses a photoelectric micro-fluidic method for automatically generating liquid drops as required, which comprises the following steps: acquiring an image of a reservoir area in a photoelectric wetting micro-fluidic chip, identifying cells in the image, and acquiring central coordinates and sizes of the cells, the sizes including the diameters of the cells; by taking the center of each cell as a reference, generating a light ring with a corresponding size, and moving the cells to the edge of the reservoir area through the light ring; according to the present invention, by combining the deep learning and the photoelectric wetting technology, the automation of the generation and the division of the sub-droplets is achieved, the manual intervention is reduced, and the experiment efficiency and the experiment accuracy are improved.

Description

Technical Field

[0001] The invention relates to the technical field of microfluidic chips, and in particular to a photoelectric microfluidic method for automatically generating droplets on demand. Background Art

[0002] Photoelectrowetting digital microfluidics technology manipulates droplets by projecting a light spot onto a photoconductive layer to generate a virtual electrode. This method can avoid the complex design and processing steps of the physical electrode circuit of the dielectric wetting chip, make up for its defect of being unable to reconstruct the electrode, and become an emerging digital microfluidics solution. Photoelectrowetting technology can produce many micrometer-scale monodisperse droplets, which can be used as small isolated micro-laboratories to avoid cross-infection between cells and limit secretions from entering the droplets for precise cell analysis. At present, droplet microfluidics has been widely used in drug encapsulation, targeted drug delivery, multifunctional carriers, algae cultivation and other fields. This technology has strong integration and makes it possible to build complex "lab-on-a-chip" systems and conduct comprehensive biological analysis.

[0003] However, the current photoelectrowetting technology lacks an effective control system to manage the generation and splitting efficiency of droplets. The number and volume of droplets are usually controlled manually, which severely limits the application prospects of photoelectrowetting technology. Many microfluidic high-throughput biological applications (such as digital nucleic acid amplification and analysis) require a large number of droplets to improve experimental efficiency. The droplets generated by manual manipulation have large volume differences, which not only reduces the repeatability of the experiment and makes it difficult to meet various experimental requirements, but also increases the sample processing time, resulting in low efficiency and limiting the diversity and adaptability of the experiment. At present, no one has combined deep learning and photoelectrowetting technology to realize the automatic on-demand generation of droplets on microfluidic chips. Therefore, it is very necessary to invent a photoelectric microfluidic method for automatically generating droplets on demand. Summary of the invention

[0004] In view of the above-mentioned prior art, the present invention provides a photoelectric microfluidic method for automatically generating droplets on demand, mainly to solve the technical problems existing in the above-mentioned background technology.

[0005] To achieve the above object, the technical solution of the embodiment of the present invention is implemented as follows:

[0006] The first aspect of the present invention discloses a photoelectric microfluidic method for automatically generating droplets on demand, the method comprising the following steps:

[0007] Acquire an image of a reservoir region in a photoelectrowetting microfluidic chip, identify cells in the image, and obtain the center coordinates and size of the cells, wherein the size includes the diameter of the cells;

[0008] Taking the center of each cell as a reference, a halo of corresponding size is generated, and the cell is moved to the edge of the reservoir area through the halo;

[0009] A light spot of corresponding size is generated and controlled to split a plurality of mother droplets containing a single cell from the reservoir region.

[0010] Optionally, an image of a reservoir area in the photoelectrowetting microfluidic chip is captured by a camera, and a YOLO algorithm is used to identify the reservoir area and cells in the reservoir area in the image to obtain the center coordinates of the cells and the diameter of the cells.

[0011] Optionally, the diameter of the light ring is larger than the diameter of the cell, and the diameter of the light spot when generating a mother droplet is larger than the diameter of the light spot when generating a daughter droplet.

[0012] Optionally, in the process of moving the cell to the edge of the reservoir area through the halo, the edge coordinates of the reservoir area are first obtained through the Canny algorithm, and the distance from the cell to the edge of the reservoir area is calculated at all times to see whether it is less than a first threshold. When it is less than the first threshold, it indicates that the cell has moved to the edge of the reservoir area.

[0013] Optionally, the process of calculating whether the distance from the cell to the edge of the reservoir area is less than a first threshold comprises:

[0014] Obtain the center coordinates of the cell and the edge coordinate set of the reservoir area;

[0015] Traversing the edge coordinate set of the reservoir area, and calculating the Euclidean distance from the center coordinate of the cell to each edge coordinate;

[0016] Find the minimum value among these distances, which is the shortest distance from the cell to the edge of the reservoir area, and compare the minimum value among the distances with the first threshold.

[0017] Optionally, generating a light spot of corresponding size and controlling the light spot to split a plurality of mother droplets containing a single cell from the reservoir area specifically includes: generating a plurality of light spots corresponding to the corresponding cell as the center, and guiding the water at the edge of the reservoir area and the cells to separate from the reservoir area through the light spots, thereby forming a plurality of mother droplets containing a single cell.

[0018] Optionally, after generating the mother droplet, the method further includes: generating a plurality of light spots corresponding to the mother droplet as the center, and the light spots surround the mother droplet, and the plurality of light spots move in different directions, thereby splitting the mother droplet into a plurality of sub-droplets.

[0019] Optionally, after driving the light spot to split a plurality of sub-droplets from the mother droplet, the method further comprises: performing anomaly detection on each sub-droplet, and for an abnormal droplet, moving the abnormal droplet back to the mother droplet by using the light spot,

[0020] Optionally, anomaly detection is performed on each sub-droplet, specifically including:

[0021] Each sub-droplet is identified by the YOLO algorithm, the boundary contour of each sub-droplet is extracted, and the diameter of each sub-droplet is calculated based on the boundary contour;

[0022] The diameters of all sub-droplets are averaged to obtain the average diameter;

[0023] For each sub-droplet, the deviation between the diameter of each sub-droplet and the average diameter is compared. If the deviation exceeds or is lower than a second threshold, the droplet is an abnormal droplet.

[0024] Optionally, for sub-droplets / mother droplets that meet the requirements, the light spot is used to guide the sub-droplets / mother droplets to move in parallel along a set moving path. During the movement of each sub-droplet / mother droplet, the current position of each sub-droplet / mother droplet is continuously updated through the recognition algorithm and the tracking algorithm until the sub-droplet / mother droplet reaches the target position.

[0025] The second aspect of the present invention discloses a photoelectric microfluidic system for automatically generating droplets on demand, wherein the system is used to implement the aforementioned method, and the control system comprises a visual acquisition module, a droplet detection and tracking module, an automatic control module, and a light spot halo generation module.

[0026] The visual acquisition module is configured to acquire images of mother droplets and daughter droplets on the photoelectric wetting microfluidic chip;

[0027] The automatic control module is used to receive input parameters from a user and determine the number of droplets to be generated based on the input parameters;

[0028] The light spot and light ring generation module is configured to generate a light spot or a light ring on the photoelectrowetting microfluidic chip, and split a daughter droplet containing a single cell from a mother droplet through the cooperation of the light spot or the light ring;

[0029] The droplet detection and tracking module is configured to obtain the current position of each sub-droplet in the droplet array through a recognition algorithm, and to continuously update the current position of each sub-droplet through a recognition algorithm and a tracking algorithm to achieve sub-droplet tracking.

[0030] The beneficial effects of the present invention are: 1. By combining deep learning and photoelectrowetting technology, the automation of droplet generation and splitting is achieved, human intervention is reduced, and experimental efficiency and accuracy are improved.

[0031] 2. The system can accurately control the movement path of the light spot and the splitting process of the droplets, ensuring that the generated droplets have consistent volume and shape, which is suitable for high-throughput biological and chemical analysis and meets experimental requirements.

[0032] 3. Monitor the volume of droplets in real time to ensure that the volume of each droplet meets the requirements during the experiment, and handle and replenish abnormal droplets in time to improve the reliability of the experiment. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a schematic diagram of the structure of the photoelectrowetting microfluidic chip in the embodiment of the present application;

[0034] Figure 2 It is a schematic diagram of a process of an optoelectronic microfluidic method for automatically generating droplets on demand in an embodiment of the present application;

[0035] Figure 3 is a schematic diagram of the result of generating mother droplets according to an embodiment of the present invention;

[0036] Figure 4 This is a schematic diagram of the result of splitting the mother droplet according to an embodiment of the present invention.

[0037] Figure 5 is a framework diagram of the detection and tracking process provided by an embodiment of the present invention;

[0038] Figure 6 is a schematic diagram of tracking results provided by an embodiment of the present invention;

[0039] Figure 7 It is a module block diagram of an optoelectronic microfluidic system for automatically generating droplets on demand according to an embodiment of the present invention;

[0040] Figure 8 It is a principle block diagram of a photoelectric microfluidic system for automatically generating droplets on demand in an embodiment of the present application.

[0041] Description of Figure Numbers:

[0042] 1. Visual acquisition module; 2. Droplet detection and tracking module; 3. Automatic control module; 4. Light spot halo generation module; 11. Upper glass base; 12. Upper indium tin oxide film; 13. Upper hydrophobic layer; 14. Droplet layer; 15. Lower hydrophobic layer; 16. Dielectric layer; 17. Photoconductive layer; 18. Lower indium tin oxide film; 19. Lower glass base. DETAILED DESCRIPTION

[0043] The technical solution of the present invention is further elaborated in detail below in conjunction with the drawings and specific embodiments of the specification. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by technicians in the technical field of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention. In the following description, the expression "some embodiments" is related to a subset of all possible embodiments, but it should be understood that "some embodiments" can be the same subset or different subsets of all possible embodiments, and can be combined with each other without conflict.

[0044] In the following description, a large number of specific details are provided to provide a more thorough understanding of the present invention. However, it is apparent to those skilled in the art that the present invention can be implemented without one or more of these details. In other examples, in order to avoid confusion with the present invention, some technical features well known in the art are not described.

[0045] It should be understood that the present invention can be implemented in different forms and should not be interpreted as being limited to the embodiments proposed herein. On the contrary, providing these embodiments will make the disclosure thorough and complete, and the scope of the present invention will be fully conveyed to those skilled in the art. And the purpose of the terms used herein is only to describe specific embodiments and is not intended to be a limitation of the present invention. When used herein, the singular forms of "one", "one" and "said / the" are also intended to include plural forms, unless the context clearly indicates another way. It should also be understood that the terms "compose" and / or "include" when used in this specification determine the presence of the features, integers, steps, operations, elements and / or parts, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, parts and / or groups. When used herein, the term "and / or" includes any and all combinations of the relevant listed items.

[0046] It should also be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "inside", "outside", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0047] In order to fully understand the present invention, a detailed structure will be proposed in the following description to illustrate the technical solution proposed by the present invention. The optional embodiments of the present invention are described in detail as follows, but in addition to these detailed descriptions, the present invention may also have other implementations.

[0048] See also Figure 1 The photoelectrowetting microfluidic chip described in the embodiment of the present application comprises, from top to bottom, an upper glass base plate 11 (700 micrometers thick), an upper indium tin oxide film 12 (200 nanometers thick), an upper hydrophobic layer 13 (50 nanometers thick), a droplet layer 14 (130 micrometers thick), a lower hydrophobic layer (50 nanometers thick), a dielectric layer 16 (1 micrometer thick), a photoconductive layer 17 (1 micrometer thick), a lower indium tin oxide film 18 (200 nanometers thick) and a lower glass base plate 19 (700 micrometers thick), and the upper indium tin oxide film 12 and the lower indium tin oxide film 18 serve as electrodes. In order to facilitate the separation of multiple sub-droplets containing only a single cell from the reservoir area of ​​the photoelectrowetting microfluidic chip, the first aspect of the present invention discloses a photoelectromicrofluidic method for automatically generating droplets on demand, see Figure 2 , the method comprises the following steps:

[0049] S1, acquiring an image of a reservoir area in a photoelectrowetting microfluidic chip, identifying cells in the image, and obtaining the center coordinates and size of the cells, wherein the size includes the diameter of the cells;

[0050] S2, taking the center of each cell as a reference, generating a halo of corresponding size, and moving the cell to the edge of the reservoir area through the halo;

[0051] S3. Generate a light spot of corresponding size, and control the light spot to split a plurality of mother droplets containing a single cell from the reservoir area.

[0052] It should be noted that the "reservoir" refers to a specific area on the photoelectrowetting microfluidic chip used to store and provide liquid (such as a solution containing cells), and the liquid in the "reservoir" area is usually injected from the outside. This area on the chip is designed to hold liquid and can interact with it through external means (such as optical control) to achieve functions such as droplet generation, movement and splitting.

[0053] In an optional implementation of step S1, an image of a reservoir area in a photoelectrowetting microfluidic chip is captured by a camera, and a YOLO algorithm is used to identify the reservoir area and cells in the reservoir area in the image to obtain the center coordinates and diameter of the cells.

[0054] In an optional embodiment of step S2, a halo larger than each selected cell is generated for each selected cell with each selected cell as the center. For example, the radius of the halo is set to 1.2 times the diameter of the cell. The movement of the halo drives the cell to move to the edge of the mother droplet.

[0055] Furthermore, in the process of moving the cell to the edge of the reservoir area through the halo, the edge coordinates of the reservoir area are first obtained through the Canny algorithm, and the distance from the cell to the edge of the reservoir area is calculated at all times to see whether it is less than the first threshold. When it is less than the first threshold, it means that the cell has moved to the edge of the reservoir area.

[0056] In an optional embodiment, the process of calculating whether the distance from the cell to the edge of the reservoir area is less than a first threshold comprises:

[0057] Obtain the center coordinates of the cell and the edge coordinate set of the reservoir area;

[0058] Traversing the edge coordinate set of the reservoir area, and calculating the Euclidean distance from the center coordinate of the cell to each edge coordinate;

[0059] Find the minimum value among these distances, which is the shortest distance from the cell to the edge of the reservoir area, and compare the minimum value among the distances with the first threshold value. The first threshold value may be 5 microns, that is, when the Euclidean distance from the center coordinate of the cell to at least one edge coordinate is less than 5 microns, it indicates that the cell has reached the edge of the reservoir area.

[0060] See also Figure 3 In an optional embodiment of step S3, generating a light spot of a corresponding size and controlling the light spot to split a plurality of mother droplets containing a single cell from the reservoir region specifically includes:

[0061] A plurality of light spots are generated correspondingly with the corresponding cells as the center, and the water at the edge of the reservoir area and the cells are guided to separate from the reservoir area through the light spots, thereby forming a plurality of mother droplets containing single cells.

[0062] In another embodiment of the present invention, the generated mother droplet may not contain a single cell. During the generation process, a plurality of light spots are first generated at the edge of the reservoir area, and the movement of the light spots is used to guide the splitting of corresponding mother droplets from the water in the reservoir area. Under this condition, based on the target requirements, the light spots are further driven to split a plurality of daughter droplets from the mother droplet.

[0063] Driving the light spot to split a plurality of sub-droplets from a mother droplet specifically includes: taking the mother droplet as the center, generating a plurality of light spots correspondingly, wherein the diameter of the light spot is equal to the diameter of the required sub-droplet, and the number of the generated light spots is the same as the number of the required sub-droplets, and the light spots surround the mother droplet, and the plurality of light spots move in different directions, thereby splitting the mother droplet into a plurality of sub-droplets.

[0064] For example, in one embodiment of the present invention, a plurality of light spots are generated with the mother droplet as the center, and the center angles between each light spot are equal. By moving the light spot, a plurality of sub-droplets are simultaneously separated from the mother droplet, so that the mother droplet can be evenly divided, such as Figure 4 .

[0065] It should be noted that in the process of obtaining mother droplets and daughter droplets, the diameter of the halo is larger than the diameter of the cell, and the spot diameter when generating mother droplets is larger than the spot diameter when generating daughter droplets.

[0066] Furthermore, after driving the light spot to split a plurality of sub-droplets from the mother droplet, the method further includes: performing anomaly detection on each sub-droplet, and for an abnormal droplet, moving the abnormal droplet back to the mother droplet by using the light spot,

[0067] Among them, anomaly detection is performed on each sub-droplet, specifically including:

[0068] Each sub-droplet is identified by the YOLO algorithm, the boundary contour of each sub-droplet is extracted, and the diameter of each sub-droplet is calculated based on the boundary contour;

[0069] The diameters of all sub-droplets are averaged to obtain the average diameter;

[0070] For each sub-droplet, compare the deviation of the diameter of each sub-droplet with the average diameter. If the deviation exceeds or is lower than the second threshold, which may be ±10%, the droplet is an abnormal droplet. That is, when the diameter of a small droplet exceeds or is lower than 10% of the average diameter, the small droplet is regarded as an abnormal droplet. For the abnormal droplet, the abnormal droplet is moved back to the mother droplet through the light spot.

[0071] In an optional embodiment, for the sub-droplets / mother droplets that meet the requirements, the light spots are used to guide the sub-droplets / mother droplets to move in parallel along the set moving paths. During the movement of each sub-droplet / mother droplet, the current position of each sub-droplet / mother droplet is continuously updated by the recognition algorithm and the tracking algorithm until the sub-droplet / mother droplet reaches the target position. The method of continuously updating the current position of each sub-droplet by the recognition algorithm and the tracking algorithm specifically includes:

[0072] Identify multiple sub-droplets / mother droplets in the target image of the previous frame through a recognition algorithm to obtain the bounding box coordinates and bounding box ID name of each sub-droplet / mother droplet in the previous frame;

[0073] The bounding box coordinates of the previous frame of multiple sub-droplets / mother droplets are simultaneously input into the Kalman filter, and the positions of the multiple droplets in the next frame are predicted according to the speed and position of the corresponding sub-droplets / mother droplets;

[0074] The multiple sub-droplets / mother droplets in the target image of the current frame are identified by a recognition algorithm to obtain the bounding box coordinates of each sub-droplet / mother droplet in the current frame.

[0075] Specifically, when performing motion detection, first obtain the target image of the previous frame in a stationary state, and use the recognition algorithm to identify the target image of the previous frame to obtain the bounding box coordinates of each child droplet / mother droplet in the previous frame, and assign a corresponding bounding box ID name to each bounding box. The obtained bounding box coordinates are input into the Kalman filter, and the Kalman filter predicts the possible position of each droplet in the current frame, and then obtain the target image of the current frame in a moving state, and use the recognition algorithm to identify the target image of the current frame to obtain the bounding box coordinates of each droplet in the current frame, where the bounding box of the current frame has two types of high confidence and low confidence.

[0076] For the identified bounding box of the current frame, ID matching needs to be performed. The ID matching adopts two-step matching. The first matching is for the bounding box coordinates of the current frame with high confidence, and the IoU calculation is performed between it and the corresponding predicted position of the Kalman filter. If the IoU is greater than the set threshold, it is considered that the bounding box coordinates of the current frame of the droplet match the predicted position, and the bounding box ID name of the previous frame of the corresponding droplet is assigned to the bounding box of the current frame;

[0077] The second match is for the low-confidence bounding box that has not been matched yet, and the IoU calculation is performed again. If the IoU between the low-confidence bounding box and the predicted position is greater than the threshold, the bounding box ID name of the previous frame of the corresponding droplet is assigned to the bounding box of the current frame.

[0078] In a possible implementation, if any bounding box of the current frame cannot be assigned a corresponding bounding box ID of the previous frame, a new bounding box ID is assigned to the bounding box.

[0079] The detection and tracking results are as follows Figure 5-Figure 6 As shown in Figure 1, in case S1, the confidence level of all target detections is very high. At this time, the detection and tracking results are relatively ideal, and all targets are correctly identified and tracked in the first matching process;

[0080] In case S2, there is a low-confidence target in the field of view. The low-confidence target is marked in red, and through two IoU calculations and matching processes, a suitable ID is assigned to ensure the continuity of tracking;

[0081] In case S3, there is a new target. If the IoU between a certain prediction box output by the model and all the prediction boxes is lower than the threshold and the total number of prediction boxes is greater than the number of bounding box IDs, it is considered that there is a new target and a new ID is assigned to the newly detected target.

[0082] Further, adjusting the corresponding light spot according to the deviation between the updated current position of the sub-droplet and the target position specifically includes adjusting the position or shape of the corresponding light spot according to the deviation.

[0083] Exemplarily, for each child droplet / mother droplet, the deviation between its current position and the nearest point on the target path is calculated, and the nearest point can be determined by calculating the distance from the current position of the child droplet / mother droplet to all points on the target path, and then selecting the point with the smallest distance. If the deviation exceeds a threshold, it is considered that the child droplet / mother droplet has deviated from the predetermined path.

[0084] If the sub-droplet / mother droplet deviates from the predetermined path, the position or shape of the light spot is adjusted to guide the sub-droplet / mother droplet back to the predetermined path. For example, if the sub-droplet / mother droplet deviates to the left, the light spot on the right can be strengthened to guide the sub-droplet / mother droplet to move to the right.

[0085] In summary, in the specific implementation of the present invention, a mixed liquid of deionized water and Chlorella solution is injected into the chip through a syringe pump. After the biological sample is introduced into the chip, the cells are randomly distributed. Then the number z, size and position of the sub-droplets to be split are set artificially, and the image of the reservoir area in the photoelectric wetting microfluidic chip is collected by a camera, and the reservoir area and the cells in the reservoir area in the image are identified using the YOLO algorithm to obtain the center coordinates of the cell and the diameter of the cell. The center of each cell is used as a reference to generate a halo of corresponding size. Next, by manipulating the halo, a single cell is moved to the edge of the reservoir area and the edge of the mother droplet. After moving to the edge of the reservoir area, the halo is switched to switch to a larger light spot. Through the movement of the light spot, z mother droplets containing a single cell are guided to split from the water in the reservoir area to achieve accurate encapsulation of a single cell. At the same time, by adjusting the size and position of the light spot, it is ensured that the cell will not be damaged during the movement, and can accurately reach the predetermined position.

[0086] In addition, the present invention can also generate multiple light spots at the edge of the reservoir area, guide the mother droplet containing no cells to be split from the water in the reservoir area by moving the light spots, and split multiple child droplets from the mother droplet by adjusting the size and position of the light spots after the mother droplet containing no cells is split, and detect the number of child droplets at this time and whether there are child droplets with abnormal volumes. If the number of child droplets does not meet the requirements, the number of generated droplets is reset and child droplets are regenerated. If there are child droplets with abnormal volumes, the middle droplet is moved into the mother droplet, the number of generated droplets is reset and child droplets are regenerated.

[0087] See also Figures 7 and 8The second aspect of the present invention discloses a photoelectric microfluidic system for automatically generating droplets on demand, and the system is used to implement the above method. The control system includes a visual acquisition module 1, a droplet detection and tracking module 2, an automatic control module 3, and a light spot halo generation module 4.

[0088] The visual acquisition module 1 is configured to acquire images of mother droplets and daughter droplets on the photoelectric wetting microfluidic chip;

[0089] The droplet detection and tracking module 2 is configured to obtain the current position of each sub-droplet in the droplet array through a recognition algorithm, and to continuously update the current position of each sub-droplet through a recognition algorithm and a tracking algorithm to achieve sub-droplet tracking.

[0090] The automatic control module 3 is used to receive input parameters from the user, and determine the number of droplets generated based on the input parameters, and display the moving path;

[0091] The light spot halo generating module 4 is configured to generate a light spot or halo on the photoelectrowetting microfluidic chip, and split a daughter droplet containing a single cell from a mother droplet through the cooperation of the light spot or halo;

[0092] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. The protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A photoelectric microfluidic method for automatically generating droplets on demand, characterized in that: The method comprises the following steps: Acquire an image of a reservoir region in a photoelectrowetting microfluidic chip, identify cells in the image, and obtain the center coordinates and size of the cells, wherein the size includes the diameter of the cells; Taking the center of each cell as a reference, a halo of corresponding size is generated, and the cell is moved to the edge of the reservoir area through the halo; A light spot of corresponding size is generated and controlled to split a plurality of mother droplets containing a single cell from the reservoir region.

2. The optoelectronic microfluidic method for automatically generating droplets on demand according to claim 1, characterized in that: The image of the reservoir area in the photoelectrowetting microfluidic chip is collected by a camera, and the YOLO algorithm is used to identify the reservoir area and cells in the reservoir area in the image to obtain the center coordinates and diameter of the cells.

3. The optoelectronic microfluidic method for automatically generating droplets on demand according to claim 2, characterized in that: The diameter of the light ring is larger than the diameter of the cell, and the diameter of the light spot when generating a mother droplet is larger than the diameter of the light spot when generating a daughter droplet.

4. The optoelectronic microfluidic method for automatically generating droplets on demand according to claim 3, characterized in that: In the process of moving the cell to the edge of the reservoir area through the halo, the edge coordinates of the reservoir area are first obtained through the Canny algorithm, and the distance from the cell to the edge of the reservoir area is calculated at all times to see whether it is less than the first threshold. When it is less than the first threshold, it means that the cell has moved to the edge of the reservoir area.

5. The optoelectronic microfluidic method for automatically generating droplets on demand according to claim 4, characterized in that: The process of calculating whether the distance from the cell to the edge of the reservoir area is less than a first threshold comprises: Obtain the center coordinates of the cell and the edge coordinate set of the reservoir area; Traversing the edge coordinate set of the reservoir area, and calculating the Euclidean distance from the center coordinate of the cell to each edge coordinate; Find the minimum value among these distances, which is the shortest distance from the cell to the edge of the reservoir area, and compare the minimum value among the distances with the first threshold.

6. The optoelectronic microfluidic method for automatically generating droplets on demand according to claim 5, characterized in that: The generating of a light spot of corresponding size and controlling the light spot to split a plurality of mother droplets containing a single cell from the reservoir area specifically comprises: taking the corresponding cell as the center, generating a plurality of light spots correspondingly, guiding the water at the edge of the reservoir area and the cells to separate from the reservoir area through the light spots, thereby forming a plurality of mother droplets containing a single cell.

7. The optoelectronic microfluidic method for automatically generating droplets on demand according to claim 1, characterized in that: After generating the mother droplet, the method further includes: generating a plurality of light spots corresponding to the mother droplet as the center, and the light spots surround the mother droplet, and the plurality of light spots move in different directions, thereby splitting the mother droplet into a plurality of daughter droplets.

8. The optoelectronic microfluidic method for automatically generating droplets on demand according to claim 7, characterized in that: After driving the light spot to split a plurality of sub-droplets from the mother droplet, the method further includes: performing anomaly detection on each sub-droplet, for an abnormal droplet, moving the abnormal droplet back to the mother droplet by the light spot, and performing anomaly detection on each sub-droplet, specifically including: Each sub-droplet is identified by the YOLO algorithm, the boundary contour of each sub-droplet is extracted, and the diameter of each sub-droplet is calculated based on the boundary contour; The diameters of all sub-droplets are averaged to obtain the average diameter; For each sub-droplet, the deviation between the diameter of each sub-droplet and the average diameter is compared. If the deviation exceeds or is lower than a second threshold, the droplet is an abnormal droplet.

9. The optoelectronic microfluidic method for automatically generating droplets on demand according to claim 8, characterized in that: For sub-droplets / mother droplets that meet the requirements, the light spot is used to guide the sub-droplets / mother droplets to move in parallel along the set moving path. During the movement of each sub-droplet / mother droplet, the current position of each sub-droplet / mother droplet is continuously updated through the recognition algorithm and the tracking algorithm until the sub-droplet / mother droplet reaches the target position.

10. The optoelectronic microfluidic method for automatically generating droplets on demand according to any one of claims 1 to 9, characterized in that: The method is applied to an optoelectronic microfluidic system for automatically generating droplets on demand. The control system includes a visual acquisition module, a droplet detection and tracking module, an automatic control module, and a light spot halo generation module. The visual acquisition module is configured to acquire images of mother droplets and daughter droplets on the photoelectric wetting microfluidic chip; The automatic control module is used to receive input parameters from the user, and determine the number of droplets generated based on the input parameters, and display the moving path; The light spot and light ring generation module is configured to generate a light spot or a light ring on the photoelectrowetting microfluidic chip, and split a daughter droplet containing a single cell from a mother droplet through the cooperation of the light spot or the light ring; The droplet detection and tracking module is configured to obtain the current position of each sub-droplet in the droplet array through a recognition algorithm, and to continuously update the current position of each sub-droplet through a recognition algorithm and a tracking algorithm to achieve sub-droplet tracking.

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