A multi-faceted imaging visual inspection system and inspection method

Abstract

The invention discloses a multi-faceted imaging visual inspection system and an inspection method. The system comprises: a camera, a lens, a lens module, a light source bracket, a first screw rod, a connecting plate, and an industrial computer subsystem. The inspection method comprises: sending a signal to an X-direction displacement device through an adaptive control subsystem to move the camera to a certain position and then fix it, and make the workpiece to be measured be in the center of the image; sending a corresponding signal to a Z-direction displacement device through an adaptive control subsystem to adjust the working distance between the imaging device and the workpiece to be measured to a certain range and then fix it; designing a field of view range according to the size of the area to be detected, sending a corresponding signal to a first motor through the adaptive control subsystem to rotate a first screw rod to adjust the height in a small range in the Z direction; adjusting the light source bracket to adapt to the light source according to the size of the light source required by the workpiece to be detected, turning on the light source to irradiate the surface of the workpiece to be measured, and the camera collects the front image of the workpiece and the two side image images in the prism through the lens.

Description

Technical Field

[0001] The present invention relates to the field of visual imaging technology, and in particular to a multi-faceted imaging visual detection system and detection method. Background Art

[0002] Currently, semiconductor component inspection is commonly used, such as circuit boards, LED chips, etc. The surface features of individual components are increasing, and the appearance structure is becoming more and more complex. Traditional visual imaging devices can only capture one surface to be inspected. For products with multiple surfaces to be inspected, multiple cameras need to be set up to perform imaging inspections from different directions, which not only increases costs, but also the setting of multiple cameras will inevitably occupy a large number of workstations, resulting in a complex overall structure of the inspection device and making it difficult to install. Therefore, the development of a new type of multi-faceted imaging visual inspection system is of great significance for improving the accuracy and efficiency of surface defect detection of components with complex appearance structures. Summary of the invention

[0003] In order to solve the above technical problems, the purpose of the present invention is to provide a multi-faceted imaging visual inspection system and inspection method, which provides technical support for the inspection of semiconductor components, ensures the product quality of components, and reduces the defective rate; at the same time, the inspection system adopts a mirror imaging method of prism reflection and refraction, which realizes the simultaneous and high-precision imaging of multiple surfaces of the workpiece to be inspected by monocular vision at a fixed station, thereby greatly saving hardware costs and improving inspection efficiency. The overall structure of the present invention is simple, the operation is stable and reliable, and it is helpful to promote the development of intelligent inspection.

[0004] The purpose of the present invention is achieved through the following technical solutions:

[0005] A multi-faceted imaging visual inspection system, comprising: a camera, a lens, a lens module, a light source bracket, a first screw rod, a connecting plate, and an industrial computer subsystem;

[0006] The camera is fixed on the connecting plate and is used to adjust the distance between the imaging component and the lens module in real time;

[0007] The camera is connected to the industrial computer subsystem and is used to transmit the collected front image of the workpiece and the mirror image of the workpiece to be detected formed by the prism to the industrial computer subsystem for analysis and processing;

[0008] The lens is installed directly below the camera and connected to the lens module, and is used to collect the reflected light from the surface of the workpiece to be measured and focus it on the camera;

[0009] The light source bracket is assembled at the first connecting rod and is used to bear the upper imaging device and different types of light sources.

[0010] A multi-faceted imaging visual inspection method, comprising:

[0011] The adaptive control subsystem sends a signal to the X-axis displacement device to move the camera to a certain position and then fix it, so that the workpiece to be measured is in the center of the image;

[0012] The adaptive control subsystem sends a corresponding signal to the Z-axis displacement device to adjust the working distance between the imaging device and the workpiece to be measured to a certain range and then fix it;

[0013] The field of view is designed according to the size of the area to be detected, and the adaptive control subsystem sends a corresponding signal to the first motor to rotate the first screw rod to adjust the height in a small range in the Z direction;

[0014] According to the size of the light source required for the workpiece to be inspected, adjust the light source bracket to adapt to the light source, turn on the light source to illuminate the surface of the workpiece to be inspected, and the camera collects the images of the front of the workpiece and the two side surfaces in the prism through the lens.

[0015] Compared with the prior art, one or more embodiments of the present invention may have the following advantages:

[0016] This system can simultaneously image the front and both sides of the workpiece to be tested, providing effective technical support for a single device to simultaneously test multiple surfaces of a workpiece at a fixed station, solving the current problem of high testing costs and low efficiency, ensuring product quality and reducing the defective rate;

[0017] The camera is connected to the lens module through the lens, which minimizes the interference of the external environment on the imaging. In addition, the distance between the imaging device and the prism can be adjusted in real time through the first screw rod to ensure the imaging quality;

[0018] The light source bracket and the imaging device are assembled in an integrated manner, which greatly simplifies the device structure and facilitates the good application of the device on the actual assembly line;

[0019] The light source bracket can be adjusted in real time according to the size of the light source used, and has good applicability;

[0020] The present invention realizes high-definition imaging of multiple surfaces of a workpiece by monocular vision, and provides new technology for the fields of visual inspection and sensing. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0022] Figure 2 It is a schematic diagram of the lens module structure of the present invention;

[0023] Figure 3 It is a schematic diagram of the structure of the light source bracket of the present invention;

[0024] Figure 4It is a schematic diagram of the working principle of the present invention;

[0025] Figure 5 is a flow chart of the visual inspection method of the present invention;

[0026] Figure 6 It is a schematic diagram of Example 2 of the present invention. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be further described in detail below in conjunction with embodiments and drawings.

[0028] like Figure 1 As shown, the overall structure of the present invention includes a camera 5, a lens 6, a lens module 7, a light source bracket 8, a first screw rod 9, a first motor 10, a coaxial light source 11, a connecting plate 12, and an industrial computer subsystem 14; the camera 5 is fixed on the connecting plate 12, and the distance between the imaging component and the lens module 7 can be adjusted in real time and conveniently; the camera 5 is connected to the industrial computer subsystem 14 through a communication interface 51, and is used to collect the mirror image of the workpiece 2 to be detected formed by the first prism 72 and the second prism 73 and the front image of the workpiece 2 to be detected and transmit the image to the industrial computer subsystem 14 for analysis and processing; the light source bracket 8 is assembled at the first connecting rod 45, which can bear the upper imaging device and different types of light sources.

[0029] The above-mentioned connecting plate 12 is assembled on the first screw rod 7 by screws, and the first screw rod 7 is installed above the light source bracket 8. By adjusting the first screw rod 9, the distance between the camera 5 and the first prism 72 and the second prism 73 can be accurately adjusted, thereby adjusting the size of the imaging field of view; the lens 6 is installed directly below the camera 5 and connected to the lens module 7, and is used to collect the reflected light from the surface of the workpiece 2 to be measured and focus it on the camera 5; the lens module 7 is assembled on the upper part of the light source bracket 8 by screws; the light source bracket 8 is fixed to the slider 43 by the first connecting rod 45; the industrial computer subsystem 14 is located in the control room outside the equipment.

[0030] The X-direction displacement device 4 comprises: an X-direction motor 41, a fixed block 42, a slider 43, a linear guide rail 44, and a first connecting rod 45; the Z-direction displacement device 3 comprises: a Z-direction motor 31, a Z-direction guide rail 32, and a support plate 33; the X-direction displacement device 4 is installed on the support plate 33, and the Z-direction displacement device 3 is mounted directly above the support rod 13, and a base 1 is fixed to the bottom of the support rod 13; the X-direction displacement device 4 can adjust the position of the camera 5 in the X direction by moving, so that the workpiece 2 to be measured is in the center of the image, thereby minimizing imaging distortion and improving detection accuracy; the Z-direction displacement device 3 can adjust the working distance between the imaging device and the workpiece 2 to be measured to a certain range by moving, so as to facilitate the next step of focusing imaging and small-range adjustment of the Z-direction height.

[0031] like Figure 2 As shown, the lens module 7 includes a sleeve 71, a first prism 72, a first rotating handle 74, a first prism clamp 76, a second prism 73, a second rotating handle 75, a second prism clamp 77, and a filter 78, and the lens module 7 is connected to the upper imaging device to provide mirror images of each surface of the workpiece 2 to be measured; the first prism 72 is fixed to the inner wall of the sleeve 71 through the first prism clamp 76, and the first rotating handles 74 are installed on both sides of the first prism clamp 76 to lock the prism to prevent angular deviation; similarly, the second prism 73 is fixed to the inner wall of the sleeve 71 through the second prism clamp 77, and the second rotating handles 75 are installed on both sides of the second prism clamp 77 to lock the prism to prevent angular deviation, thereby causing a change in the field of view; the sleeve 71 is assembled on the light source bracket 8 by screws to protect the internal prism and reduce imaging interference, and the filter 78 protects various optical devices from damage.

[0032] like Figure 3 As shown, the light source bracket 8 includes an upper support plate 81, a first support block 82, and a second support block 83; the upper support plate 81 includes four mutually perpendicular linear slots 811, and each linear slot 811 is equipped with a screw in its lead, and the size of the X-direction space that the light source bracket 8 can accommodate can be adjusted by moving the screw, and the four screws can be adjusted separately without interfering with each other; the first support block 82 is installed on the first screw 812 and the second screw 813 through a nut, and the second support block 83 is installed on the third screw 814 and the fourth screw 815 through a nut, and then the position of the nut on the screw is moved, so that the size of the Z-direction space that the light source bracket 8 can accommodate can be adjusted in real time.

[0033] The industrial computer subsystem 14 is located in the control room outside the equipment. The industrial computer subsystem 14 includes an information processing subsystem 141 and an adaptive control subsystem 142, and is connected to the camera 5 through the communication interface 51; the information processing subsystem 141 performs surface defect detection on the image of the workpiece 2 to be tested collected by the camera 5; the adaptive control subsystem 142 controls the first motor 10 to rotate the first screw 9, adjusts the height of the camera 5, and ensures the imaging quality.

[0034] This embodiment also provides a multi-faceted imaging visual inspection method, the method comprising:

[0035] The camera 5 is moved by the X-axis displacement device 3 so that the workpiece 2 to be measured is in the center of the image, thereby minimizing imaging distortion and improving detection accuracy; the Z-axis displacement device 3 is moved to adjust the working distance between the imaging device and the workpiece 2 to be measured to a certain range, so as to facilitate the next step of focusing imaging and small-range adjustment of the height in the Z direction; then, the adaptive control subsystem 142 sends a corresponding signal to the first motor 10 to rotate the first screw 9 to adjust the height in a small range in the Z direction, so as to achieve the optimal spacing between the camera 5 and the lens module 7;

[0036] According to the detection requirements of the workpiece 2 to be detected, a reasonable light source is selected and installed on the light source bracket 8; the coaxial light source 11 is turned on to illuminate the surface of the workpiece 2 to be detected, and the camera 5 collects the front image of the workpiece 2 to be detected and the left and right side images in the prism through the lens 6 (such as Figure 4 shown);

[0037] The information processing subsystem 141 in the industrial control computer subsystem 14 splices the collected front and two side images of the workpiece 2 to be measured, eliminates the overlapping parts between them, and then forms a new image with a large field of view, completeness and high definition containing the information of each image sequence after resampling and fusion;

[0038] The next step is to pre-process the stitched images to remove irrelevant information such as interference and noise in the images and enhance the detectability of real information, thereby maximally simplifying the data and improving the overall detection accuracy and real-time performance;

[0039] Finally, the defect detection algorithm is used to perform surface defect detection on the preprocessed workpiece image, identify and mark the defective parts, and thus reduce the defective rate of the product.

[0040] Example 2

[0041] A working state of the present invention is as follows Figure 6As shown, the size of the workpiece 2 to be tested and the detection requirements have changed. After calculation, it is necessary to adjust the position of the camera 5, the distance between the camera 5 and the first prism 72 and the second prism 73, and select the annular light source 15. Therefore, the adaptive control subsystem 142 sends a signal to the Z-direction displacement device 3 and the X-direction displacement device 4 to adjust the position of the camera 5 in the X and Z directions respectively, so that the area to be tested is in the center of the field of view and then fixes the X and Z directions; the adaptive control subsystem 142 sends a signal to the first motor 10 to rotate the first screw 9 to adjust the distance between the camera 5 and the prism to ensure the field of view size and the imaging area are complete; at this moment, the camera 5 collects images of the front and two sides of the workpiece, and transmits them to the information processing subsystem 141 in the industrial computer subsystem 14 through the communication interface 51 for surface defect detection, and marks the defective area.

[0042] Although the embodiments disclosed in the present invention are as above, the above contents are only embodiments adopted for facilitating the understanding of the present invention and are not intended to limit the present invention. Any technician in the technical field to which the present invention belongs can make any modifications and changes in the form and details of the implementation without departing from the spirit and scope disclosed in the present invention, but the patent protection scope of the present invention shall still be subject to the scope defined in the attached claims.

Claims

1. A multi-faceted imaging visual inspection system, characterized in that: The system includes: a camera, a lens, a lens module, a light source bracket, a first screw rod, a connecting plate, and an industrial computer subsystem; The camera is fixed on the connecting plate and is used to adjust the distance between the imaging component and the lens module in real time; The camera is connected to the industrial computer subsystem and is used to transmit the collected front image of the workpiece and the mirror image of the workpiece to be detected formed by the prism to the industrial computer subsystem for analysis and processing; The lens is installed directly below the camera and connected to the lens module, and is used to collect the reflected light from the surface of the workpiece to be measured and focus it on the camera; The light source bracket is mounted on the first connecting rod and is used to bear the upper imaging device and different types of light sources; The first screw is installed above the light source bracket, and the distance between the camera and the first prism and the second prism is precisely adjusted by adjusting the first screw, thereby adjusting the size of the imaging field of view; The light source bracket comprises an upper support plate, a first support block, and a second support block; The system also includes an X-direction displacement device and a Z-direction displacement device, wherein the X-direction displacement device includes an X-direction motor, a fixed block, a slider, a linear guide rail, and a first connecting rod; the Z-direction displacement device includes: a Z-direction motor, a Z-direction guide rail, and a support plate; the X-direction displacement device is installed on the support plate, and the Z-direction displacement device is assembled just above the support rod, and a base is fixed at the bottom of the support rod; the X-direction displacement device can adjust the position of the camera in the X direction by moving, so that the workpiece to be measured is in the center of the image, thereby minimizing imaging distortion and improving detection accuracy; the Z-direction displacement device adjusts the working distance between the imaging device and the workpiece to be measured to a certain range by moving, which is used for the next step of focusing imaging and small-range adjustment of the Z-direction height; The upper support plate is provided with four mutually perpendicular linear slots, and a screw is installed in the lead of each linear slot; the first support block is installed on the first screw and the second screw through a nut, and the second support block is installed on the third screw and the fourth screw through a nut; the positions of the screws on the four linear slots of the upper support plate can be adjusted according to the size of the light source, and similarly, the first and second support blocks can adjust the four screws to meet the height requirements of the light source in the Z direction and the width requirements in the X direction to achieve light source fixation; The industrial computer subsystem includes an information processing subsystem and an adaptive control subsystem, and is connected to the camera through a communication interface; the information processing subsystem performs surface defect detection on the image of the workpiece to be tested collected by the camera; the adaptive control subsystem controls the first motor of the machine to rotate the first screw rod, adjusts the height of the camera, and ensures the imaging quality; The connecting plate is assembled on the first screw rod by screws, and the first screw rod is installed above the light source bracket; The lens module is assembled on the upper part of the light source bracket by screws; The light source bracket is fixed on the slide block via a first connecting rod; The industrial computer subsystem is located in the centralized control room outside the device; The lens module includes a sleeve, a first prism, a first prism clamp, a first rotating handle, a second prism, a second prism clamp, a second rotating handle and a filter; the lens module is connected to an upper imaging device to provide mirror images of each surface of a workpiece to be measured, the first rotating handle and the second rotating handle respectively lock the first prism and the second prism to prevent angle deviation and thus change in the field of view; the sleeve is assembled on the light source bracket by screws to protect the internal prism and reduce imaging interference, the first prism clamp and the second prism clamp are respectively fixed on the inner wall of the sleeve, and the filter is used to protect each optical device from damage.

2. The detection method of a multi-faceted imaging visual detection system as claimed in claim 1, characterized in that: The method comprises: The adaptive control subsystem sends a signal to the X-axis displacement device to move the camera to a certain position and then fix it, so that the workpiece to be measured is in the center of the image; The adaptive control subsystem sends a corresponding signal to the Z-axis displacement device to adjust the working distance between the imaging device and the workpiece to be measured to a certain range and then fix it; The field of view is designed according to the size of the area to be detected, and the adaptive control subsystem sends a corresponding signal to the first motor to rotate the first screw rod to adjust the height in a small range in the Z direction; According to the size of the light source required by the workpiece to be inspected, adjust the light source bracket to adapt to the light source, turn on the light source to illuminate the surface of the workpiece to be inspected, and the camera collects the images of the front of the workpiece and the two side surfaces of the workpiece in the prism through the lens; The information processing subsystem stitches the collected images of the front and two sides of the workpiece to eliminate the overlapping parts, and then forms a new image with a large field of view, completeness and high definition containing the information of each image sequence after resampling and fusion; Preprocess the stitched images to remove irrelevant information such as interference and noise in the images and enhance the detectability of real information; The defect detection algorithm is used to detect surface defects on the preprocessed workpiece image, identify and mark the defective parts, thereby reducing the defective rate of the product.

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