An imaging assembly and imaging system

Abstract

The application relates to the field of semiconductor processing equipment, and particularly relates to a semiconductor detection equipment, in particular to an imaging assembly and an imaging system. In the technical scheme provided by the embodiment of the application, a color imaging component is vertically arranged relative to a to-be-detected object, a black-and-white imaging assembly and a projection assembly are arranged around the color imaging component, two-dimensional image and three-dimensional image are obtained, a coaxial light source and a first ring-shaped light source are arranged on the color imaging component to realize high-angle bright field illumination, a second ring-shaped light source is further arranged, a plurality of colored lamp beads are arranged in the second ring-shaped light source, and different spectrum illuminations are formed among the plurality of lamp beads. In the embodiment, a multilayer structure is arranged based on bright-dark field illumination of the second ring-shaped light source, each layer has a different incident angle, so that the second ring-shaped light source realizes the switching and selection of bright-dark field illumination while realizing the multi-spectrum illumination.

Description

Technical Field

[0001] This application relates to the field of semiconductor processing equipment, specifically to a semiconductor inspection device, and more specifically, to an imaging component and an imaging system. Background Technology

[0002] The core of a machine vision system is image acquisition and processing. All information originates from images, and image quality is crucial to the entire vision system. A camera needs a light source to capture images, illuminating the feature locations to be captured while ensuring image quality remains consistent regardless of ambient light changes. This results in images with clearly defined features and sufficient contrast, facilitating further image processing by the software algorithm. Different light source configurations are required for different detection items to highlight their contrast within the image. Therefore, there is currently no universal machine vision lighting device suitable for all detection needs. For each specific case, a suitable lighting setup must be designed to achieve the best image results.

[0003] With advancements in semiconductor manufacturing technology, it has become increasingly difficult to achieve complete point clouds using only binocular reconstruction and DLP reconstruction. Furthermore, the diverse image features and blind spots in semiconductor products place even more stringent demands on the light source. In current technologies, most light sources are simple and singular ring or bowl-shaped sources, which are generally difficult to integrate with multiple detection items, resulting in less than ideal image quality. Summary of the Invention

[0004] To address the aforementioned technical problems, embodiments of this application provide an imaging component and imaging system that efficiently integrates 2D detection and 3D point cloud reconstruction, and merges multi-view point cloud reconstruction and DLP point cloud reconstruction, effectively solving the problems of accuracy and compatibility.

[0005] To achieve the above objectives, the technical solutions adopted in the embodiments of this application are as follows:

[0006] In a first aspect, an imaging assembly is provided, comprising: a color imaging component disposed relative to an object to be detected, wherein the receiving surface is disposed parallel to the surface of the object to be detected, for acquiring a color image of the object to be detected; a black and white imaging assembly comprising at least one black and white imaging component, wherein at least one of the black and white imaging components is disposed at an angle relative to the object to be detected, and the black and white imaging component has the same field of view height as the color imaging component, for acquiring a black and white image of the object to be detected; and a projection assembly comprising at least one projection component, wherein the light emitting surface of at least one of the projection components is disposed relative to the object to be detected, for projecting a stripe projection onto the object to be detected.

[0007] In another possible implementation, the black-and-white imaging assembly includes a plurality of black-and-white imaging components uniformly arranged around the color imaging component, and the plurality of black-and-white imaging components have independent imaging control channels.

[0008] In another possible implementation, the projection assembly includes a plurality of projection elements uniformly arranged around the color imaging element, with each projection element positioned between adjacent black-and-white imaging elements.

[0009] In another possible implementation, the color imaging component includes a telecentric lens and a color camera.

[0010] In another possible implementation, the black-and-white imaging component includes a Sham telecentric lens and a black-and-white camera.

[0011] In a second aspect, an imaging system is provided, comprising an imaging component as described in any of the preceding claims, and further comprising a light source component disposed on a color imaging component, the light source component comprising an annular light source disposed on the receiving surface of the color imaging component, and a coaxial light source having the same propagation path as the light path of the color imaging component; the light emitting surfaces of the annular light source and the coaxial light source are disposed relative to the object to be detected.

[0012] In another possible implementation, the color temperature of the coaxial light source is 3200k.

[0013] In another possible implementation, the ring light source includes a plurality of uniformly arranged red and blue LEDs, and the emitted light from the ring light source has a 5° angle with the vertical direction of the surface of the object to be tested.

[0014] In another possible implementation, the imaging system further includes a second annular light source disposed between the imaging component and the object to be detected. The light-emitting surface of the second annular light source faces the surface of the object to be detected. The second annular light source includes a plurality of uniformly distributed LEDs of different colors, including red, green, blue and white light. Each LED of a color is configured with an independent control channel, and LEDs of different colors are combined to form different spectral illuminations.

[0015] In another feasible approach, the second annular light source has a multi-layer structure, with each layer having a combination of LED beads of different colors and each layer having a different incident angle.

[0016] In another possible implementation, the second ring light source includes a first ring light, a second ring light, a third ring light, a fourth ring light, and a fifth ring light arranged relative to the object to be detected from near to far.

[0017] In another feasible embodiment, the incident angle of the first ring light is 10°, and multiple white and blue LEDs are arranged evenly spaced within the first ring light, with the multiple white and blue LEDs being independently controlled through different channels.

[0018] In another possible implementation, the incident angle of the second ring light is 15°, and multiple blue LEDs are arranged within the second ring light. The multiple blue LEDs are evenly distributed in multiple lighting areas, and the multiple lighting areas are independently controlled through different channels.

[0019] In another feasible embodiment, the incident angle of the third ring light is 30°, and multiple green and blue LEDs are arranged evenly spaced within the third ring light, with the multiple green and blue LEDs being independently controlled through different channels.

[0020] In another feasible embodiment, the incident angle of the fourth ring light is 45°, and multiple red and blue LEDs are arranged evenly spaced within the fourth ring light, with the multiple red and blue LEDs being independently controlled through different channels.

[0021] In another feasible embodiment, the incident angle of the fifth ring light is 75°, and multiple red and green LEDs are arranged evenly spaced within the fifth ring light, with the multiple red and green LEDs being independently controlled through different channels.

[0022] The embodiments of the present invention bring the following beneficial effects:

[0023] The technical solution provided in this application embodiment offers an imaging component and an imaging system, including a color imaging component vertically arranged opposite to the object to be detected, and a black-and-white imaging component and a projection component arranged around the color imaging component, enabling the acquisition of two-dimensional and three-dimensional images. A coaxial light source and a first ring light are provided on the color imaging component to achieve high-angle bright-field illumination. The system also includes a second ring light source, in which multi-color LEDs are arranged to combine multiple LEDs to form different spectral illuminations. Furthermore, in this embodiment, the second ring light source has a multi-layer structure based on bright and dark field illumination, with each layer having a different incident angle, thus enabling the second ring light source to switch and select between bright and dark field illuminations while achieving multi-spectral illumination.

[0024] Other features and advantages of this disclosure will be set forth in the following description, or some features and advantages may be inferred from the description or determined without doubt, or may be learned by practicing the techniques described above.

[0025] To make the above-mentioned objects, features and advantages of this disclosure more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] The system shown in the accompanying drawings will be further described according to exemplary embodiments. These exemplary embodiments will be described in detail with reference to the drawings. These exemplary embodiments are non-limiting exemplary embodiments, wherein example figures represent similar mechanisms in the various views of the drawings.

[0028] Figure 1 This is a first structural schematic diagram of an imaging system provided in an embodiment of this application.

[0029] Figure 2 This is a cross-sectional view of the ring light source provided in an embodiment of this application.

[0030] Figure 3 This is a schematic diagram of the second structure of the imaging system provided in an embodiment of this application.

[0031] Figure 4 A cross-sectional view of the second annular light source provided in an embodiment of this application.

[0032] Figure 5 This is a schematic diagram of the third structure of the imaging system provided in an embodiment of this application.

[0033] Illustration:

[0034] 100 - Three-dimensional imaging system; 200 - Object to be detected;

[0035] 110 - Color imaging component; 120 - Black and white imaging component; 130 - Projection assembly; 140 - Coaxial light source; 150 - Ring light source; 160 - Second ring light source;

[0036] 111 - Color camera; 112 - Telecentric lens; 121 - Sham telecentric lens; 122 - Black and white camera; 161 - First ring light; 162 - Second ring light; 163 - Third ring light; 164 - Fourth ring light; 165 - Fifth ring light. Detailed Implementation

[0037] To better understand the above technical solutions, the technical solutions of this application will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the embodiments of this application and the specific features in the embodiments are detailed descriptions of the technical solutions of this application, rather than limitations on the technical solutions of this application. In the absence of conflict, the embodiments of this application and the technical features in the embodiments can be combined with each other.

[0038] In the detailed description below, numerous specific details are illustrated with examples to provide a comprehensive understanding of the relevant guidance. However, it will be apparent to those skilled in the art that this application can be practiced without these details. In other instances, well-known methods, procedures, systems, components, and / or circuits have been described at a relatively high level without detail to avoid unnecessarily obscuring aspects of this application.

[0039] This application provides an imaging component and imaging system for automated optical defect detection on the surface of industrial products, particularly for automated optical inspection of semiconductor products. In this embodiment, the automated optical inspection scenario for semiconductor products mainly focuses on chip packaging processes.

[0040] Specifically, chip packaging can be achieved through wire bonding, a relatively old and mature packaging technology used across various industries. A variety of wire materials are used, such as gold, copper, and aluminum wires, with the smallest wire diameter being around 20µm. The large number of wires, their varying directions and curvatures make it difficult to inspect wire arc height using traditional 2D methods. Furthermore, the thinness and numerous reflection angles of the wires make it challenging to fit point clouds using traditional 3D methods.

[0041] Specifically, semiconductor products in chip packaging technology mainly refer to IGBT devices (Insulated Gate Bipolar Transistors). As a power semiconductor device, IGBTs are widely used in rail transportation, smart grids, industrial energy conservation, electric vehicles, and new energy equipment. Wire bonding connects individual IGBT chips or DBCs to form a complete circuit structure. Even with mature bonding technology, issues such as cold solder joints and high wire arc height can still occur. Currently, the industry uses line laser scanning to generate 3D point clouds, but this has many blind spots and low accuracy. Furthermore, it cannot detect 2D-related inspection items. Therefore, a faster and more efficient 2D & 3D inspection solution is needed.

[0042] Specifically, BGA packaging is the preferred choice among existing packaging processes. BGA packaging is an emerging technology that connects wafer components to the PCB, providing more possibilities for the connection between wafer integrated circuits (ICs) and PCB circuit boards. However, BGA packaging requires certain technical requirements and precise control of the manufacturing process to ensure the accuracy of the number and position of the BGA balls, thus guaranteeing packaging quality. The desired outcome is achieved through 3D morphology and 2D dimensional inspection. Currently, spectral confocal microscopy is used for inspection, which meets the accuracy requirements but has very low inspection efficiency; while line laser DLP and other methods may meet the efficiency requirements, the required accuracy is difficult to achieve.

[0043] Therefore, for the 2D and 3D inspection of the three types of products mentioned above, it is difficult to achieve a complete point cloud using only binocular reconstruction and DLP reconstruction. Furthermore, the variable pose of gold wires, the blind spots of IGBTs, and the specular reflections of certain BGA spheres severely affect the inspection results. Such numerous and complex inspection items place even stricter requirements on the light source; most light sources used in the industry are simple and single ring or bowl-shaped light sources, which are generally difficult to be compatible with multiple inspection items, resulting in less than ideal image quality.

[0044] Therefore, in order to solve the problems existing in the above-mentioned technologies, this embodiment provides an imaging system that can realize automatic optical detection in complex scenes.

[0045] For details, please refer to Figure 1 This is a schematic diagram of an imaging system structure provided in this embodiment. The imaging system 100 includes an imaging component and a light source component. The imaging component includes a color imaging component 110 and a monochrome imaging component. The color imaging component is positioned relative to the object to be detected 200, with its receiving surface parallel to the surface of the object. This can be understood as the color imaging component being vertically positioned relative to the object in this embodiment. The monochrome imaging component includes at least one monochrome imaging component 120. In this embodiment, the number can be one. Unlike the color imaging component, the monochrome imaging component is tilted relative to the object to be detected, but it has the same field of view height as the color imaging component; that is, the monochrome imaging component and the color imaging component have the same setting height relative to the object.

[0046] In this embodiment, the color imaging component includes a telecentric lens 112 and a color camera 111, wherein the color camera is a CXP camera. This configuration ensures that the RGB channels of the color image acquired by the color imaging component are without positional deviation. When inspecting the object, three-channel images can be acquired in a single photograph, enabling the detection of different defects and improving inspection efficiency. The black-and-white imaging component includes a Schahm telecentric lens 121 and a black-and-white camera 122, wherein the black-and-white camera is a CXP camera. The Schahm telecentric lens effectively expands the depth of field, ensuring clear imaging of the object. In this embodiment, the black-and-white imaging component is used in conjunction with the color imaging component. By fusing the color image and the black-and-white image acquired under the same field-of-view height, a three-dimensional image reconstruction of the object to be inspected is achieved.

[0047] Furthermore, the imaging component in this embodiment also includes a projection component 130. The projection component includes a projection element whose light-emitting surface is positioned opposite the object to be detected, for projecting transmissive stripes onto the object. The projection element employs a DLP device to project various types of stripes onto the surface of the object, and can be selectively used in conjunction with a color imaging component and a monochrome imaging component to achieve the reconstruction of 3D point clouds in different scenes.

[0048] Specifically, when the surface of the object to be detected has a specular reflection effect, the projection component is used in conjunction with the black and white imaging component to solve the problem of unclear image caused by specular reflection, thereby resolving the stripes and achieving high-precision reconstruction of 3D point cloud; when the surface of the object to be detected is not specular, the projection component is used in conjunction with the color imaging component, and the 3D point cloud is reconstructed by resolving the stripes in the same way.

[0049] Please continue reading. Figure 1 The light source assembly in this embodiment includes an annular light source 150 disposed at the receiving surface of the color imaging component, and a coaxial light source 140 having the same propagation path as the light path of the color imaging component, wherein the light emitting surfaces of the annular light source and the coaxial light source are disposed opposite to the object to be detected.

[0050] In this embodiment, the coaxial light source is a coaxial point light source. In order to make reasonable use of the three RGB channels of the color camera and prevent the RGB single channel of a color image from being overexposed or underexposed, the coaxial light source is a high-brightness light source composed of LEDs with a color temperature of 3200k.

[0051] See Figure 2 The image shown is a cross-sectional view of the ring light source in this embodiment. The ring light source contains multiple evenly arranged red and blue LEDs, and the emitted light from the ring light source forms a 5° angle with the vertical direction, creating high-angle illumination for illuminating objects with slight tilt.

[0052] Furthermore, to adapt to the image feature representation of different detection scenarios and different detection objects, this embodiment also provides a second ring light source 160 with multispectral illumination. The second ring light source is positioned between the imaging component and the object to be detected, with its light-emitting surface facing the surface of the object. It includes multiple uniformly distributed LEDs of different colors, each with its own independent control channel. Different colored LEDs combine to form different spectral illuminations, and the corresponding LED is activated according to the detection object.

[0053] The second ring light source contains multiple LEDs of various colors, including red, green, blue, and white, which produce corresponding red, green, blue, and white light when activated. For example, when inspecting gold wires, because the gold wires are small in diameter and numerous, their direction and curvature vary significantly. A single light source cannot capture the required features, so a contrasting color principle is used to increase the contrast between the gold wires and the background. Specifically, the red, blue, green, and white LEDs are first activated, and corresponding color images are acquired using the color imaging component to detect defects such as bending, broken lines, and double wires. After acquisition, the blue LED is activated, and corresponding point cloud images are acquired using the color imaging component, the black-and-white imaging component, and the projection component. Based on the point cloud images, the arc height and collapsed lines of the gold wires are detected.

[0054] Furthermore, in order to meet the requirements for both bright and dark optical fields in complex detection scenarios, the second ring light source in this embodiment is preferably a multi-layer structure, with each layer having a different incident angle.

[0055] For details, please refer to Figure 3 For the optimized imaging system, the second ring light source in this system has a five-layer structure. The first ring light 161, the second ring light 162, the third ring light 163, the fourth ring light 164 and the fifth ring light 165 are arranged in order from near to far from the object to be detected. Each layer is equipped with a combination of LED beads of different colors, and each layer has a different incident angle.

[0056] Please see Figure 4 The image shown is a cross-sectional view of the second annular light source in this embodiment. The first annular light is incident at an angle of 10° to create dark field illumination. Multiple white and blue LEDs are evenly spaced within the first annular light. The white LEDs are independently controlled via a first channel, and the blue LEDs are independently controlled via a second channel.

[0057] The second ring light has an incident angle of 15° to form dark-field illumination. Since the second ring light is used for contour imaging in this embodiment, multiple blue LEDs within the second ring light are uniformly distributed across multiple illumination areas, and each illumination area is independently controlled via a different channel to achieve contour imaging. Furthermore, the number of these illumination areas is preferably four; that is, the second ring light has four illumination areas, which are independently controlled via a third, fourth, fifth, and sixth channel.

[0058] The third ring light has an incident angle of 30° to form dark field illumination. Green and blue LEDs are arranged evenly spaced within the third ring light. Multiple green LEDs and multiple blue LEDs are independently controlled through the seventh and eighth channels, respectively.

[0059] The fourth ring light has an incident angle of 45° to form bright field illumination. Red and blue LEDs are arranged evenly spaced within the fourth ring light. Multiple red LEDs and multiple blue LEDs are independently controlled through the ninth and tenth channels, respectively.

[0060] The fifth ring light has an incident angle of 75° for bright field illumination. The fifth ring light is equipped with multiple red LEDs and multiple green LEDs that are evenly distributed. The multiple red LEDs and multiple green LEDs are independently controlled through the eleventh channel and the second channel, respectively.

[0061] In this embodiment, the second ring light combines multispectral and bright / dark field illumination, and together with the coaxial light source and the first ring light source, it serves as a system-level light source, enabling its application in various detection scenarios and for lighting and imaging of various detection targets. For example, in 2D project detection of defects in bonded materials, IGBTs, and BGA materials, including but not limited to foreign objects, scratches, chipping, bridging, oxidation discoloration, deformation, pits, protrusions, cracks, and other abnormalities, the coaxial light source and the first ring light are first activated to form high-angle bright field illumination and acquire a first image of the object to be detected. Then, the first, third, fourth, fifth, and sixth channels of the second ring light are activated to form low-angle dark field illumination and acquire a second image of the object to be detected. Through the comparison and processing of the bright and dark field images, a comprehensive expression of different features can be achieved, making the final detection result more accurate.

[0062] For further details, please refer to [link / reference]. Figure 5 This embodiment optimizes the structure of the aforementioned imaging device to achieve multi-directional image acquisition and more complete 3D point cloud reconstruction. Specifically, the black-and-white imaging component in this structure includes multiple black-and-white imaging parts 120, which are symmetrically arranged around the color imaging part, and a projection component 130 is provided between each black-and-white imaging part.

[0063] In this embodiment, the number of black and white imaging components includes two or four, preferably four. That is, four black and white imaging components are evenly arranged around the color imaging component, and four projection components are arranged between each black and white imaging component, also in a uniform distribution.

[0064] The optimized imaging device increases the field of view by adding more black-and-white imaging components and projection components, thus avoiding blind spots caused by a single black-and-white imaging component. The four black-and-white imaging components have independent imaging control channels. By controlling two relatively positioned black-and-white imaging components and a color imaging component, a binocular 3D imaging device can be formed. In this embodiment, the four black-and-white imaging components can be combined in pairs based on their relative relationships to construct binocular 3D imaging devices under different conditions. Furthermore, the four projection components can also be independently controlled according to the correspondence of the black-and-white imaging components. For example, for the anomaly detection of silver paste in the packaging structure, the detection mainly focuses on its area, contour, and adhesion height. The area and contour detection are achieved by controlling the activation of the first, third, fourth, fifth, and sixth channels to use low-to-medium angle blue light illumination for dark-field imaging. For adhesion height, while maintaining constant light source control, the four black-and-white imaging components are activated to image and construct a 3D image. The corresponding height information is obtained based on the constructed 3D image.

[0065] In summary, this application provides an imaging system including a color imaging component vertically positioned relative to the object to be detected, and a black-and-white imaging component and a projection component surrounding the color imaging component, enabling the acquisition of two-dimensional and three-dimensional images. The color imaging component is equipped with a coaxial light source and a first ring light to achieve high-angle bright-field illumination. It also includes a second ring light, in which multi-color LEDs are incorporated to combine and form different spectral illuminations. Furthermore, in this embodiment, the second ring light source has a multi-layered structure based on bright and dark field illumination, with each layer having a different incident angle, thus enabling the second ring light source to switch and select between bright and dark field illuminations while simultaneously achieving multi-spectral illumination.

[0066] This embodiment efficiently integrates 2D detection and 3D point cloud reconstruction through this configuration. The fusion of multi-view point cloud reconstruction and DLP point cloud reconstruction effectively solves the problems of accuracy and compatibility, enabling high-precision point cloud reconstruction for both highly reflective and diffusely reflective objects. Furthermore, the light source enhancement design, through the above configuration, effectively reduces exposure time and increases production capacity. The combination of various light sources and the independent control of multiple channels allow for the use of different wavelengths and angles of light sources for different detection projects to obtain optimal image effects, improving the compatibility of the light source scheme. The application of the SAM lens effectively solves the depth-of-field problem, providing a good image foundation for multi-view reconstruction and DLP reconstruction. The above configuration, along with the configuration of 2D and 3D detection hardware, maximizes the compatibility of the equipment, allowing a single device to produce multiple materials, thus saving costs.

[0067] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0068] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An imaging component, characterized in that, include: A color imaging component is positioned relative to the object to be detected, with its receiving surface parallel to the surface of the object to be detected, for acquiring a color image of the object to be detected; A black-and-white imaging component includes at least one black-and-white imaging element, wherein at least one of the black-and-white imaging elements is tilted relative to the object to be detected, and the black-and-white imaging element has the same field of view height as the color imaging element, for acquiring a black-and-white image of the object to be detected; A projection assembly includes at least one projection component, wherein the light-emitting surface of at least one of the projection components is disposed relative to the object to be tested, for projecting stripe projections onto the object to be tested.

2. The imaging component according to claim 1, characterized in that, The black-and-white imaging component includes multiple black-and-white imaging elements, which are uniformly arranged around the color imaging component, and each of the multiple black-and-white imaging elements has an independent imaging control channel.

3. The imaging component according to claim 2, characterized in that, The projection assembly includes multiple projection components, which are uniformly arranged around the color imaging component, and each projection component is disposed between adjacent black and white imaging components.

4. The imaging component according to claim 1, characterized in that, The color imaging component includes a telecentric lens and a color camera.

5. The imaging component according to claim 1, characterized in that, The black-and-white imaging component includes a Sham telecentric lens and a black-and-white camera.

6. An imaging system, characterized in that, The imaging component includes the imaging component as described in any one of claims 1-5, and further includes a light source component disposed on the color imaging component. The light source component includes an annular light source disposed on the receiving surface of the color imaging component, and a coaxial light source having the same propagation path as the light path of the color imaging component. The light emitting surfaces of the annular light source and the coaxial light source are disposed relative to the object to be detected.

7. The imaging system according to claim 6, characterized in that, The color temperature of the coaxial light source is 3200k.

8. The imaging system according to claim 6, characterized in that, The ring light source includes multiple uniformly arranged red and blue LEDs, and the emitted light from the ring light source has a 5° angle with the vertical direction of the surface of the object to be tested.

9. The imaging system according to claim 6, characterized in that, The imaging system further includes a second ring light source disposed between the imaging component and the object to be detected. The light-emitting surface of the second ring light source faces the surface of the object to be detected. The second ring light source includes multiple uniformly distributed LED beads of different colors. The colors of the multiple LED beads include red light, green light, blue light, and white light. Each color of LED bead is configured with an independent control channel. The LED beads of different colors are combined to form different spectral illumination.

10. The imaging system according to claim 9, characterized in that, The second ring light source has a multi-layer structure, with each layer having a combination of LED beads of different colors and each layer having a different incident angle.

11. The imaging system according to claim 10, characterized in that, The second ring light source includes a first ring light, a second ring light, a third ring light, a fourth ring light, and a fifth ring light arranged relative to the object to be detected from near to far.

12. The imaging system according to claim 11, characterized in that, The incident angle of the first ring light is 10°. Multiple white and blue LEDs are arranged evenly spaced within the first ring light. The multiple white and blue LEDs are controlled independently through different channels.

13. The imaging system according to claim 11, characterized in that, The incident angle of the second ring light is 15°. Multiple blue LED beads are arranged within the second ring light and are evenly distributed in multiple lighting areas. The multiple lighting areas are independently controlled through different channels.

14. The imaging system according to claim 11, characterized in that, The incident angle of the third ring light is 30°. Multiple green and blue LED beads are arranged evenly spaced within the third ring light. The multiple green and blue LED beads are independently controlled through different channels.

15. The imaging system according to claim 11, characterized in that, The incident angle of the fourth ring light is 45°. Multiple red and blue LEDs are evenly distributed within the fourth ring light. The multiple red and blue LEDs are independently controlled through different channels.

16. The imaging system according to claim 11, characterized in that, The fifth ring light has an incident angle of 75°. Multiple red and green LEDs are evenly distributed within the fifth ring light, and each of the multiple red and green LEDs is independently controlled through a different channel.

Images