Method and equipment for detecting welding defects of micro-fluidic chip and medium thereof

Abstract

The invention relates to the technical field of welding detection, in particular to a method and equipment for detecting welding defects of a micro-fluidic chip and a medium of the micro-fluidic chip. The method comprises the following steps: placing a to-be-detected micro-fluidic chip on a bearing platform of a sample bearing unit, positioning a to-be-detected sample in a detection area, and fixing the to-be-detected micro-fluidic chip by using a clamping device; the driving unit drives the laser excitation unit to move to the to-be-detected micro-fluidic chip, the laser excitation unit carries out laser excitation on the to-be-detected micro-fluidic chip, and after excitation, the double-wave hybrid laser interferometer is used for obtaining an ultrasonic signal transmitted back from a weld joint of the to-be-detected micro-fluidic chip; the electric signals are transmitted to the defect classification processing unit; and the defect classification processing unit receives the electric signal, analyzes the electric signal, and performs defect identification on the to-be-detected micro-fluidic chip based on an analysis result, so that the welding defect detection of the micro-fluidic chip is realized, the welding surface and the welding interior can be detected, and the detection precision and the detection efficiency are high.

Description

Technical Field

[0001] The present invention relates to the technical field of welding detection, and in particular to a method, equipment and medium for detecting welding defects of a microfluidic chip. Background Art

[0002] Microfluidic chips are highly integrated microfluidic manipulation devices that are widely used in medical diagnosis, bioanalysis, chemical synthesis and other fields. They are usually made of plastic materials (such as PMMA, PC), which are widely used in the manufacture of microfluidic chips due to their light weight, low cost and easy processing. However, welding is a key process in the manufacture of microfluidic chips, and the quality of its welds directly determines the function and reliability of the chip.

[0003] Traditional detection methods such as visual inspection, mechanical testing, and microscopic observation are insensitive to tiny defects, inefficient, and easy to damage samples. To solve the above shortcomings, the prior art proposes a vision-based welding detection method, which generally collects images through a camera, compares the tested solder joints in the image with the qualified parameters in the database, and detects welding defects after image processing, such as welding wire offset, welding slag residue, welding wire size, broken welding, cold welding and other defect items. However, these tests can only detect defects on the surface of the welded sample, and cannot detect the inside of the sample welding, which is not suitable for welding detection of microfluidic chips. Summary of the invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art.

[0005] To this end, the present invention provides a method for detecting welding defects in a microfluidic chip, which can detect the welding surface and the inside of the welding, has high detection accuracy and high detection efficiency, and is non-contact during detection, thereby avoiding damage to the sample during the detection process.

[0006] According to the method for detecting welding defects of a microfluidic chip according to an embodiment of the present invention, the method comprises the following steps: Build a detection system, which includes: a laser excitation unit, a dual-wave hybrid laser interferometer, a sample carrying unit, a driving unit and a defect classification processing unit, wherein the sample carrying unit includes a carrying platform for placing the microfluidic chip to be detected and a clamping device for fixing the microfluidic chip to be detected, and the driving unit is used to control the movement of the laser excitation unit; The driving unit drives the laser excitation unit to move onto the microfluidic chip to be detected, and the laser excitation unit performs laser excitation on the microfluidic chip to be detected. After the excitation, a double-wave hybrid laser interferometer is used to obtain an ultrasonic signal transmitted back from the weld of the microfluidic chip to be detected, and the ultrasonic signal is converted into an electrical signal and transmitted to the defect classification processing unit; The defect classification processing unit receives the electrical signal, obtains a waveform of the electrical signal, analyzes the waveform of the electrical signal to obtain characteristic information, performs defect identification on the microfluidic chip to be inspected based on the characteristic information, and obtains the welding defect and the position of the defect of the microfluidic chip; Obtain the ultrasonic signal corresponding to the defect, and calculate the length of the microfluidic chip through which the ultrasonic signal propagates and transmits based on the time T it takes for the ultrasonic signal to be transmitted to the defect location and then to the detection point. L 2; According to the length of the ultrasonic signal passing through the microfluidic chip during propagation and transmission L 2 Calculate the depth of the defect in the microfluidic chip h .

[0007] The beneficial effect of the present invention is that the method for detecting welding defects of microfluidic chips of the present invention excites the microfluidic chip to be detected by a laser excitation unit, and after the excitation, a dual-wave hybrid laser interferometer is used to convert the ultrasonic signal into an electrical signal, and then the electrical signal is analyzed by a defect classification processing unit to realize the detection of welding defects of the microfluidic chip, with high detection accuracy and high detection efficiency. The laser excitation unit excites the microfluidic chip to be detected and does not need to make surface contact with the microfluidic chip to be detected, thereby avoiding the situation where the microfluidic chip to be detected is damaged during the detection process, and improving the yield rate of the microfluidic chip to be detected. The present invention is suitable for weld detection of microfluidic chips made of various plastic materials such as PMMA, PC, PVC, etc., has a wide adaptability, can detect micron-level defects, and meets high-precision requirements.

[0008] According to one embodiment of the present invention, step S4 specifically includes the following steps: The defect classification processing unit acquires the electrical signal, obtains a corresponding waveform graph based on the electrical signal, and compares the waveform graph with a waveform graph without defects; If the waveform diagram is similar to the defect-free waveform Figure 1 If the microfluidic chip to be tested is defective, then the microfluidic chip to be tested has no defects; Otherwise, the microfluidic chip to be tested is defective, and the process proceeds to the next step; Analyze and process the waveform diagram to obtain the characteristic information, the characteristic information includes: frequency characteristic, amplitude characteristic, phase characteristic and propagation time characteristic; The frequency characteristics, amplitude characteristics, phase characteristics and propagation time characteristics are compared with those of a defect-free chip to determine the defects of the microfluidic chip to be inspected.

[0009] According to one embodiment of the present invention, the defects include weld cracks, weld discontinuity, weld discontinuity, weld bubbles, uneven weld surface, local density reduction and / or delamination in the weld.

[0010] According to one embodiment of the present invention, comparing the frequency characteristics, amplitude characteristics, phase characteristics and propagation time characteristics with the frequency characteristics, amplitude characteristics, phase characteristics and propagation time characteristics of a defect-free device to determine the defect of the microfluidic chip to be detected specifically includes: If the amplitude of the change of the amplitude characteristic decreases relative to the amplitude characteristic without defects, the defect type is determined to be a weld crack, a weld not joined, and a weld not continuous; If the signal frequency of the change of the frequency characteristic increases or decreases relative to the frequency characteristic without defects, it is determined that the local stress of the material has changed and there are bubbles in the welding; If the phase characteristic changes to be equivalent to the phase characteristic without defects, and the phase is shifted, and the signal time distribution changes, it is determined that the weld surface is uneven; If the change in the propagation time characteristic is delayed relative to the propagation time of a defect-free state, it is determined that the local density decreases or delamination occurs in the weld.

[0011] According to an embodiment of the present invention, step S5 specifically includes: Calculate the length of ultrasonic signal propagation and transmission through the microfluidic chip L 2The calculation formula is:

[0012] in, V 1 is the velocity of the longitudinal wave in the microfluidic chip cover, V 2 is the velocity of the longitudinal wave in the microfluidic chip body, L 1 is the length of the ultrasonic wave passing through the cover during propagation and transmission; Calculating the depth of defects in microfluidic chips h , the calculation formula is:

[0013] in, x is the horizontal coordinate value of the detection point.

[0014] According to one embodiment of the present invention, the laser excitation unit includes a laser and a laser probe; The laser is connected to the laser probe via a first optical fiber to generate ultrasonic guided waves at the weld of the microfluidic chip to be detected; The receiving probe of the dual-wave hybrid laser interferometer is connected to the dual-wave hybrid laser interferometer through a second optical fiber. The receiving probe is used to receive the ultrasonic signal transmitted back from the weld of the microfluidic chip to be detected, and convert the ultrasonic signal into an electrical signal through the dual-wave hybrid laser interferometer.

[0015] According to one embodiment of the present invention, the laser is a nano-pulse fiber laser with a wavelength of 1064 nm.

[0016] According to one embodiment of the present invention, frequency features, amplitude features, phase features and propagation time features are extracted by performing difference analysis on the electrical signal.

[0017] A computer device according to an embodiment of the present invention includes: processor; A memory for storing executable instructions; Wherein, the processor is used to read the executable instructions from the memory and execute the executable instructions to implement the above-mentioned method for detecting welding defects of a microfluidic chip.

[0018] According to a computer-readable storage medium of an embodiment of the present invention, the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the processor implements the above-mentioned method for detecting welding defects in a microfluidic chip.

[0019] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention are realized and obtained by the structures particularly pointed out in the description, claims and drawings.

[0020] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0022] Figure 1 It is a schematic diagram of the method flow of embodiment 1 of the present invention.

[0023] Figure 2 It is a partial schematic diagram of the detection system of the first embodiment of the present invention.

[0024] Figure 3 It is a schematic diagram of depth detection of defects in the first embodiment of the present invention.

[0025] Figure 4 This is a schematic diagram of a waveform diagram of a welding crack defect in the first embodiment of the present invention, wherein: Figure 4 (a) is a schematic diagram of a microfluidic chip with a welding crack defect on its surface. Figure 4 (b) is the waveform diagram of the corresponding welding crack defect.

[0026] Figure 5 1 is a schematic diagram comparing waveforms of a weld with delamination defect and a weld without defect in the first embodiment of the present invention, wherein: Figure 5 (a) is a schematic diagram of a microfluidic chip with delamination defects in the weld. Figure 5 (b) is a waveform comparison diagram of welds with and without delamination defects.

[0027] Figure 6 It is a schematic diagram of the computer device structure of the second embodiment of the present invention.

[0028] In the figure, 10 is a computer device; 1002 is a processor; 1004 is a memory; and 1006 is a transmission device. DETAILED DESCRIPTION

[0029] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, which only illustrate the basic structure of the present invention in a schematic manner, and therefore only show the components related to the present invention.

[0030] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0031] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0032] Example 1 The present application embodiment provides a method for detecting welding defects of a microfluidic chip, such as Figure 1 As shown, the method comprises the following steps: S1, build a detection system, such as Figure 2 As shown, the detection system includes: a laser excitation unit, a dual-wave hybrid laser interferometer, a sample carrying unit, a driving unit, and a defect classification processing unit. The sample carrying unit includes a carrying platform for placing the microfluidic chip to be detected, and a clamping device for fixing the microfluidic chip to be detected. The driving unit is used to control the movement of the laser excitation unit. Specifically, the laser excitation unit is connected to the dual-wave hybrid laser interferometer signal, the dual-wave hybrid laser interferometer is connected to the defect classification processing unit, and the driving unit is connected to the laser excitation unit.

[0033] S2, driving the laser excitation unit to move to the microfluidic chip to be inspected through the driving unit, such as moving to any welding area of ​​the microfluidic chip to be inspected, and the laser excitation unit performs laser excitation on the microfluidic chip to be inspected. After the excitation, a dual-wave hybrid laser interferometer is used to obtain the ultrasonic signal returned from the weld of the microfluidic chip to be inspected, and convert it into an electrical signal for transmission to the defect classification processing unit.

[0034] S3, the defect classification processing unit receives the electrical signal, obtains a waveform of the electrical signal, analyzes the waveform of the electrical signal, obtains feature information, and performs defect identification on the microfluidic chip to be inspected based on the feature information to obtain the welding defects and defect locations of the microfluidic chip; S4, obtain the ultrasonic signal corresponding to the defect, and calculate the length of the microfluidic chip through which the ultrasonic signal propagates and transmits based on the time T that the ultrasonic signal transmits to the defect location and then transmits to the detection point. L 2; S5, based on the length of the ultrasonic signal passing through the microfluidic chip during propagation and transmission L 2 Calculate the depth of the defect in the microfluidic chip h .

[0035] It should be noted that before executing step S2, the microfluidic chip to be tested is placed on the carrying platform of the sample carrying unit, and the sample to be tested is located in the detection area. The microfluidic chip to be tested is fixed by a clamping device to avoid detection errors due to sample shaking or instability, thereby improving detection accuracy.

[0036] In this embodiment, the detection of the microfluidic chip for defect identification in step S3 specifically includes the following steps: The defect classification processing unit obtains the electrical signal and obtains the corresponding waveform diagram based on the electrical signal. Figure 4 As shown, Figure 4 (a) shows a schematic diagram of a microfluidic chip with a welding crack defect on its surface. Figure 4 (b) is the waveform of the corresponding welding crack defect. Compare the waveform with the waveform without defects. If the waveform is different from the waveform without defects, Figure 1 If yes, the microfluidic chip to be tested has no defects; otherwise, the microfluidic chip to be tested has defects and proceeds to the next step.

[0037] Analyze and process the waveform to obtain frequency characteristics, amplitude characteristics, phase characteristics and propagation time characteristics; for example, by performing differential analysis and extraction on the electrical signal, frequency characteristics, amplitude characteristics, phase characteristics and propagation time characteristics are obtained. For example, when a delamination defect occurs, compared with when there is no defect, part of the ultrasonic signal passes through a layer of air during propagation, and its propagation time will be delayed. Through differential analysis and extraction, the propagation time characteristics can be obtained. Compare the frequency characteristics, amplitude characteristics, phase characteristics and propagation time characteristics with those of the defect-free frequency characteristics, amplitude characteristics, phase characteristics and propagation time characteristics to determine the defects of the microfluidic chip to be tested. The defects include cracks in the weld, unjoined welds, discontinuous welds, bubbles in the weld, uneven weld surface, local density reduction and / or delamination in the weld.

[0038] In this embodiment, the frequency characteristics, amplitude characteristics, phase characteristics and propagation time characteristics are compared with those of a defect-free microfluidic chip to determine that the defects of the microfluidic chip to be detected specifically include: If the amplitude characteristic changes relative to the amplitude characteristic without defects, the defect type is determined to be a weld crack, a weld not joined, or a weld not continuous; If the signal frequency of the frequency characteristic changes relative to the frequency characteristic without defects increases or decreases, it is determined that the local stress of the material has changed and there are bubbles in the weld; If the phase characteristic changes to be equivalent to the phase characteristic without defects, and the phase shifts, and the signal time distribution changes, it is determined that the weld surface is uneven; If the change in the propagation time characteristic is delayed relative to the propagation time of the defect-free propagation time, it is determined that the local density is reduced or there is delamination in the weld, such as Figure 5 As shown, Figure 5 (a) is a schematic diagram of a microfluidic chip with delamination defects in the weld. Figure 5 (b) is a waveform comparison diagram of welds with and without delamination defects.

[0039] In this embodiment, by detecting the depth of the microfluidic chip defect, the welding quality can be evaluated according to the welding defect depth, so as to facilitate the subsequent defect repair of the microfluidic chip according to the defect depth. Figure 3 As shown, The calculation formula for calculating the time T for the ultrasonic signal to be transmitted to the defect location and then to the detection point is: T = T 1 +T 2 in, T 1 is the time it takes for the ultrasonic wave to propagate to the defect position after laser excitation, T 2 is the time it takes for the ultrasonic wave to be transmitted from the defect location back to the detection point.

[0040] The length of the ultrasonic signal passing through the microfluidic chip during the propagation and transmission process is calculated based on the time T taken for the ultrasonic signal to be transmitted to the defect location and then to the detection point. L 2The calculation formula is:

[0041] in, V 1 is the velocity of the longitudinal wave in the microfluidic chip cover, V 2 is the velocity of the longitudinal wave in the microfluidic chip body, L 1 is the length of the cover sheet during the propagation and transmission of the ultrasonic wave. Since the cover sheet is thin, the length of the cover sheet during the propagation of the longitudinal wave from the excitation point to the detection point is L 1 can be approximated as 0.8 mm.

[0042] It should be noted that the velocity v of the longitudinal wave can be expressed as:

[0043] in, E is the elastic modulus (Young's modulus), P is the dielectric density of the material, which is the material property itself. For example, the elastic modulus of a PMMA cover sheet is generally about 2.0-3.3 GPa, and the dielectric density is generally about 1.18-1.20 g / cm 3 (or 1180–1200kg / m 3 ), the longitudinal wave velocity is about 2700 m / s. The elastic modulus and medium density of the material can be found from the material database, and then the velocity of the longitudinal wave in the microfluidic chip can be obtained. V1 and the velocity of longitudinal waves in the microfluidic chip cover V 2.

[0044] Based on the length of ultrasonic signal passing through the microfluidic chip during propagation and transmission L 2 Calculating the depth of microfluidic chip defects h The calculation formula is:

[0045] in, x is the horizontal coordinate value of the detection point.

[0046] In this embodiment, the laser excitation unit includes a laser and a laser probe; the laser is connected to the laser probe through a first optical fiber to generate ultrasonic guided waves at the weld of the microfluidic chip to be detected; the receiving probe of the dual-wave hybrid laser interferometer is connected to the dual-wave hybrid laser interferometer through a second optical fiber, which is used to detect the ultrasonic signal transmitted back from the weld of the microfluidic chip to be detected, and convert the ultrasonic signal into an electrical signal through the dual-wave hybrid laser interferometer. The laser uses but is not limited to a nano-pulse fiber laser with a wavelength of 1064nm. The 1064nm nano-pulse fiber laser can generate high-energy single laser pulses, stronger processing capabilities and higher efficiency; it has a narrower line width, and the wavelength distribution of the laser beam is more concentrated, which helps to reduce measurement errors, improve analysis accuracy, and is low in price.

[0047] In this embodiment, the defect classification processing unit can be a host computer. After the dual-wave hybrid laser interferometer converts the ultrasonic signal into an electrical signal, it is transmitted to the host computer for processing. The host computer can also transmit a driving signal to the driving unit. After receiving the driving signal, the driving unit controls the movement of the laser excitation unit. That is, the driving unit is also connected to the laser probe signal. By driving the laser probe, the welding area of ​​the microfluidic chip to be inspected can be excited point by point, ensuring the accuracy of the excitation range and positioning, thereby realizing automated detection.

[0048] In summary, the method for detecting welding defects in microfluidic chips of the present invention excites the microfluidic chip to be detected by a laser excitation unit, and after the excitation, a dual-wave hybrid laser interferometer is used to convert the ultrasonic signal into an electrical signal, and then the electrical signal is analyzed by a defect classification processing unit to realize the detection of welding defects in the microfluidic chip, with high detection accuracy and high detection efficiency. The laser excitation unit excites the microfluidic chip to be detected and does not need to make surface contact with the microfluidic chip to be detected, thereby avoiding the situation where the microfluidic chip to be detected is damaged during the detection process, and improving the yield rate of the microfluidic chip to be detected. The present invention is suitable for weld detection of microfluidic chips made of various plastic materials such as PMMA, PC, PVC, etc., has a wide adaptability, can detect micron-level defects, and meet high-precision requirements.

[0049] Example 2 An embodiment of the present application provides a computer device, which includes a processor and a memory, wherein the memory stores at least one instruction or at least one program, and the at least one instruction or the at least one program is loaded and executed by the processor to implement a method for detecting welding defects in a microfluidic chip as provided in the above method embodiment.

[0050] Figure 6 The hardware structure diagram of a device for implementing a method for detecting welding defects of a microfluidic chip provided in an embodiment of the present application is shown. The device may participate in constituting or include the apparatus or system provided in an embodiment of the present application. Figure 6 As shown, the computer device 10 may include one or more processors 1002 (the processor may include but is not limited to a processing device such as a microprocessor MCU or a programmable logic device FPGA), a memory 1004 for storing data, and a transmission device 1006 for communication functions. In addition, it may also include: a display, an input / output interface (I / O interface), a universal serial bus (USB) port (which may be included as one of the ports of the I / O interface), a network interface, a power supply and / or a camera. It can be understood by those skilled in the art that Figure 6 The structure shown is only for illustration and does not limit the structure of the above electronic device. Figure 6 More or fewer components as shown, or with Figure 6 Different configurations are shown.

[0051] It should be noted that the one or more processors and / or other data processing circuits described above may generally be referred to herein as "data processing circuits". The data processing circuits may be embodied in whole or in part as software, hardware, firmware, or any other combination thereof. In addition, the data processing circuit may be a single independent processing module, or may be incorporated in whole or in part into any of the other components in the computer device 10 (or mobile device). As described in the embodiments of the present application, the data processing circuit acts as a processor control (e.g., selection of a variable resistor terminal path connected to an interface).

[0052] The memory 1004 can be used to store software programs and modules of application software, such as a program instruction / data storage device corresponding to a microfluidic chip welding defect detection method in an embodiment of the present application. The processor executes various functional applications and data processing by running the software programs and modules stored in the memory 1004, that is, implementing the above-mentioned method. The memory 1004 may include a high-speed random access memory, and may also include a non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some instances, the memory 1004 may further include a memory remotely arranged relative to the processor, and these remote memories may be connected to the computer device 10 via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0053] The transmission device 1006 is used to receive or send data via a network. The specific example of the above network may include a wireless network provided by a communication provider of the computer device 10. In one example, the transmission device 1006 includes a network adapter (Network Interface Controller, NIC), which can be connected to other network devices through a base station so as to communicate with the Internet. In one example, the transmission device 1006 can be a radio frequency (RF) module, which is used to communicate with the Internet wirelessly.

[0054] The display may be, for example, a touch screen liquid crystal display (LCD) that enables a user to interact with a user interface of the computer device 10 (or mobile device).

[0055] Example 3 An embodiment of the present application also provides a computer-readable storage medium, which can be set in a server to store at least one instruction or at least one program related to a method for detecting welding defects in a microfluidic chip in an embodiment of the method. The at least one instruction or the at least one program is loaded and executed by the processor to implement a method for detecting welding defects in a microfluidic chip provided in the above-mentioned method embodiment.

[0056] Optionally, in this embodiment, the storage medium may be located in at least one of the multiple network servers of the computer network. Optionally, in this embodiment, the storage medium may include, but is not limited to, various media that can store program codes, such as a USB flash drive, a read-only memory (ROM), a random access memory (RAM), a mobile hard disk, a magnetic disk, or an optical disk.

[0057] Example 4 The embodiment of the present invention further provides a computer program product or a computer program, which includes computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium, and the processor executes the computer instructions, so that the computer device executes a method for detecting welding defects in a microfluidic chip provided in the above various optional embodiments.

[0058] It should be noted that the above-mentioned sequence of the embodiments of the present application is for description only and does not represent the advantages and disadvantages of the embodiments. The above-mentioned specific embodiments of the present application are described. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in an order different from that in the embodiments and still achieve the desired results. In addition, the processes depicted in the drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0059] Each embodiment in this application is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the device, equipment and storage medium embodiments, since they are basically similar to the method embodiments, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment.

[0060] A person skilled in the art will understand that all or part of the steps to implement the above embodiments may be accomplished by hardware or by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, and the above-mentioned storage medium may be a read-only memory, a disk or an optical disk, etc.

[0061] Based on the above ideal embodiments of the present invention, the relevant staff can make various changes and modifications without departing from the technical concept of the present invention through the above description. The technical scope of the present invention is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A method for detecting welding defects of a microfluidic chip, characterized in that: The method comprises the following steps: Build a detection system, which includes: a laser excitation unit, a dual-wave hybrid laser interferometer, a sample carrying unit, a driving unit and a defect classification processing unit, wherein the sample carrying unit includes a carrying platform for placing the microfluidic chip to be detected and a clamping device for fixing the microfluidic chip to be detected, and the driving unit is used to control the movement of the laser excitation unit; The driving unit drives the laser excitation unit to move onto the microfluidic chip to be detected, and the laser excitation unit performs laser excitation on the microfluidic chip to be detected. After the excitation, a double-wave hybrid laser interferometer is used to obtain an ultrasonic signal transmitted back from the weld of the microfluidic chip to be detected, and the ultrasonic signal is converted into an electrical signal and transmitted to the defect classification processing unit; The defect classification processing unit receives the electrical signal, obtains a waveform of the electrical signal, analyzes the waveform of the electrical signal to obtain characteristic information, performs defect identification on the microfluidic chip to be inspected based on the characteristic information, and obtains the welding defect and the position of the defect of the microfluidic chip; Obtain the ultrasonic signal corresponding to the defect, and calculate the length of the microfluidic chip through which the ultrasonic signal propagates and transmits based on the time T it takes for the ultrasonic signal to be transmitted to the defect location and then to the detection point. L 2; According to the length of the ultrasonic signal passing through the microfluidic chip during propagation and transmission L 2 Calculate the depth of the defect in the microfluidic chip h .

2. The method for detecting welding defects of a microfluidic chip according to claim 1, characterized in that: Defect identification of the microfluidic chip to be inspected specifically includes the following steps: The defect classification processing unit acquires the electrical signal, obtains a corresponding waveform graph based on the electrical signal, and compares the waveform graph with a waveform graph without defects; If the waveform diagram is consistent with the defect-free waveform diagram, then the microfluidic chip to be tested is defect-free; Otherwise, the microfluidic chip to be tested is defective, and the process proceeds to the next step; Analyze and process the waveform diagram to obtain the characteristic information, wherein the characteristic information includes: frequency characteristics, amplitude characteristics, phase characteristics and propagation time characteristics; The frequency characteristics, amplitude characteristics, phase characteristics and propagation time characteristics are compared with those of a defect-free chip to determine the defects of the microfluidic chip to be inspected.

3. The method for detecting welding defects of a microfluidic chip according to claim 2, characterized in that: The defects include weld cracks, weld discontinuity, weld discontinuity, weld bubbles, uneven weld surface, local density reduction and / or delamination in the weld.

4. The method for detecting welding defects of a microfluidic chip according to claim 3, characterized in that: Comparing the frequency characteristics, amplitude characteristics, phase characteristics and propagation time characteristics with those of a defect-free microfluidic chip to determine the defects of the microfluidic chip to be detected specifically includes: If the amplitude of the change of the amplitude characteristic decreases relative to the amplitude characteristic without defects, the defect type is determined to be a weld crack, a weld not joined, and a weld not continuous; If the signal frequency of the change of the frequency characteristic increases or decreases relative to the frequency characteristic without defects, it is determined that the local stress of the material has changed and there are bubbles in the welding; If the phase characteristic changes to be equivalent to the phase characteristic without defects, and the phase is shifted, and the signal time distribution changes, it is determined that the weld surface is uneven; If the change in the propagation time characteristic is delayed relative to the propagation time of a defect-free state, it is determined that the local density decreases or delamination occurs in the weld.

5. The method for detecting welding defects of a microfluidic chip according to claim 1, characterized in that: Calculate the length of ultrasonic signal propagation and transmission through the microfluidic chip L 2The calculation formula is: in, T It is the time it takes for the ultrasonic signal to be transmitted to the defect location and then to the detection point. V 1 is the velocity of the longitudinal wave in the microfluidic chip cover, V 2 is the velocity of the longitudinal wave in the microfluidic chip body, L 1 is the length of the ultrasonic wave passing through the cover during propagation and transmission; Calculating the depth of defects in microfluidic chips h , the calculation formula is: in, x is the horizontal coordinate value of the detection point.

6. The method for detecting welding defects of a microfluidic chip according to claim 1, characterized in that: The laser excitation unit includes a laser and a laser probe; The laser is connected to the laser probe via a first optical fiber to generate ultrasonic guided waves at the weld of the microfluidic chip to be detected; The receiving probe of the dual-wave hybrid laser interferometer is connected to the dual-wave hybrid laser interferometer through a second optical fiber. The receiving probe is used to receive the ultrasonic signal transmitted back from the weld of the microfluidic chip to be detected, and convert the ultrasonic signal into an electrical signal through the dual-wave hybrid laser interferometer.

7. The method for detecting welding defects of a microfluidic chip according to claim 6, characterized in that: The laser adopts a nanometer pulse fiber laser with a wavelength of 1064nm.

8. The method for detecting welding defects of a microfluidic chip according to claim 2, characterized in that: The frequency characteristics, amplitude characteristics, phase characteristics and propagation time characteristics are extracted by performing differential analysis on the electrical signals.

9. A computer device, characterized in that: include: processor; A memory for storing executable instructions; Wherein, the processor is used to read the executable instructions from the memory, and execute the executable instructions to implement the microfluidic chip welding defect detection method as described in any one of claims 1 to 8.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the processor implements the method for detecting welding defects in a microfluidic chip according to any one of claims 1 to 8.

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