Double-color illumination frame extraction detection system

Abstract

The utility model provides a double-color illumination frame extraction detection system, which comprises a scanning platform, an illumination device and a detection camera, the circuit board is conveyed through the scanning platform, and the top surface of the circuit board and the hole wall of a through hole are irradiated through cooperative work of a top detection lamp box and a backlight detection lamp box in the lighting device, so that images collected by the detection camera are comprehensive; the lighting device integrates two lighting modes of a white-light lighting combination and an infrared-red-light lighting combination, and can efficiently detect different types of defects. A white-light illumination combination is suitable for detecting defects such as scratches and stains on the surface of the circuit board under visible light, and an infrared-red-light illumination combination is good at detecting defects such as recesses in the circuit board which are difficult to observe through common white light, so that the limitation of a single illumination mode in a traditional detection method is solved; therefore, the detection system can simultaneously detect defects such as scratches and stains on the surface of the circuit board and hidden defects such as internal recesses and the like, and the comprehensiveness and accuracy of detection are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of circuit board detection, and particularly relates to a two-color illumination frame extraction detection system. Background Technique

[0002] The detection technology of line scanning imaging system is widely used in the fields of PCB board (Printed Circuit Board) detection, glass panel detection, cloth detection, printed product detection, semiconductor detection, new energy detection, etc.

[0003] At present, in the field of machine vision detection, in the current circuit board (PCB board) detection field, traditional detection systems often rely on a single light source illumination method, such as only using white light or infrared light for illumination. However, this method has limitations in detecting various defects of the circuit board, and the defects of the circuit board cannot be fully revealed under a single illumination method, resulting in poor detection accuracy.

[0004] Therefore, it is necessary to provide a two-color illumination frame extraction detection system to solve the above technical problems. Content of the Utility Model

[0005] The utility model provides a two-color illumination frame extraction detection system to solve the problem that the light source illumination method of the existing circuit board frame extraction detection system is single and has limitations in detecting various defects of the circuit board.

[0006] To solve the above technical problems, the technical solution of the utility model is: a two-color illumination frame extraction detection system, which includes:

[0007] A scanning platform for supporting the circuit board. A light-transmitting opening is arranged at the position corresponding to the circuit board on the scanning platform, and through holes are arranged on the circuit board.

[0008] An illumination device, which includes:

[0009] A top detection light box located above the scanning platform for irradiating the top surface of the circuit board. The top detection light box includes a top white light module and a top infrared light module; and

[0010] A backlight detection light box located below the light-transmitting opening for irradiating the hole wall of the through hole of the circuit board. The backlight detection light box includes a back white light module and a back red light module;

[0011] A detection camera located above the scanning platform. The detection camera collects images of the circuit board on the scanning platform under the illumination of the illumination device; and

[0012] Wherein, the illumination device includes two illumination modes: a white light illumination combination and an infrared red light illumination combination;

[0013] When the lighting device adopts the white - white light illumination combination, both the top white - light module and the back white - light module emit white light, and the detection camera can detect scratches and stain defects on the image of the circuit board.

[0014] When the lighting device adopts the infrared - red light illumination combination, the top infrared - light module emits white light, the back red - light module emits red light, and the detection camera can detect concave defects on the image of the circuit board.

[0015] In the present utility model, the top detection light box includes:

[0016] A first box body, the first box body is provided with a first light - emitting port facing the circuit board and a detection port oppositely arranged with the first light - emitting port;

[0017] A left - side light - source assembly, located inside the first box body on the side close to the first light - emitting port, the left - side light - source assembly irradiates the circuit board from one side, and the left - side light - source assembly includes a left white - light module and a left infrared - light module;

[0018] A right - side light - source assembly, located inside the first box body on the side close to the first light - emitting port, the right - side light - source assembly is oppositely arranged with the left - side light - source assembly, the right - side light - source assembly irradiates the circuit board from the other side, and the right - side light - source assembly includes a right white - light module and a right infrared - light module;

[0019] A beam splitter, connected to the first box body, the beam splitter is obliquely arranged between the first light - emitting port and the detection port, and the beam splitter is located inside the first box body on the side close to the detection port; and

[0020] A top light - source assembly, connected to the first box body, located inside the first box body on the side close to the detection port, the top light - source assembly is oppositely arranged with respect to the beam splitter, and the light of the top light - source assembly is directed towards the beam splitter and irradiates the circuit board after being reflected by the beam splitter.

[0021] In the present utility model, the back - light detection light box includes:

[0022] A second box body, provided with a second light - emitting port facing the circuit board;

[0023] A back - light source assembly, connected to the second box body, used for emitting light to irradiate the through - hole wall of the circuit board, including the back white - light module and the back red - light module; wherein, the light emitted by the back - light source assembly irradiates the through - hole wall of the circuit board, and after being reflected by the circuit board, it passes through the beam splitter and forms an image at the detection port.

[0024] In the present utility model, the top detection light box further includes:

[0025] A left diffuser plate, connected to the first box body, is arranged between the left light source assembly and the first light outlet; and

[0026] A right diffuser plate, connected to the first box body, is arranged between the right light source assembly and the first light outlet;

[0027] The left diffuser plate and the right diffuser plate are arranged opposite to each other, and the planes where the left diffuser plate is located, the right diffuser plate is located, and the first light outlet is located are arranged in a triangle.

[0028] In the present utility model, the top detection light box further includes a top diffuser plate, which is located between the top light source assembly and the beam splitter.

[0029] In the present utility model, the top detection light box further includes a back diffuser plate, which is arranged between the back light source assembly and the second light outlet.

[0030] In the present utility model, the back light source assembly is adjustably connected to the second box body.

[0031] In the present utility model, the second box body is provided with a connection hole and an arc-shaped adjustment groove. The arc-shaped adjustment groove is located above the connection hole, and the opening of the arc-shaped adjustment groove faces the connection hole. The back light source assembly is connected to the connection hole by a screw, and the back light source assembly is adjustably connected to the arc-shaped adjustment groove by a screw, so that the light source assembly can be rotationally adjusted with the connection hole as the center.

[0032] In the present utility model, the included angle between the plane where the beam splitter is located and the plane where the second light outlet is located is between 30° and 50°.

[0033] In the present utility model, the included angle between the back diffuser plate and the plane where the second light outlet is located is between 5° and 45°.

[0034] Compared with the prior art, the beneficial effects of the present utility model are as follows: A two-color illumination frame extraction detection system of the present utility model conveys a circuit board through a scanning platform. The top detection light box and the backlight detection light box in the illumination device work together to irradiate the top surface and the through-hole wall of the circuit board, so that the images collected by the detection camera are comprehensive; the illumination device integrates two illumination modes of white-white light illumination combination and infrared-red light illumination combination, and can efficiently detect different types of defects. The white-white light illumination combination is suitable for detecting defects such as scratches and stains on the surface of the circuit board under visible light, while the infrared-red light illumination combination is more suitable for detecting defects such as depressions inside the circuit board that are difficult to observe through ordinary white light.

[0035] In view of the limitations of the single illumination method in traditional detection methods, this solution uses two sets of detection light rays and performs frame-by-frame detection with two frames, enabling the detection system to detect defects on the surface of the circuit board and defects under the ink on the surface of the circuit board, such as scratches, stains and other defects, as well as hidden defects such as depressions inside the circuit board, improving the comprehensiveness and accuracy of detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments. The drawings in the following description are only the corresponding drawings of some embodiments of the present invention.

[0037] Figure 1 Schematic diagram of the overall structure of the preferred embodiment of the present invention.

[0038] Figure 2 Schematic diagram of the internal structure of the top detection light box of the preferred embodiment of the present invention.

[0039] Figure 3 Schematic diagram of the internal structure of the backlight detection light box of the preferred embodiment of the present invention.

[0040] Figure 4 Schematic diagram of the arc adjustment groove structure of the preferred embodiment of the present invention.

[0041] Figure 5 Defect diagram of the circuit board under the white light illumination combination of the preferred embodiment of the present invention.

[0042] Figure 6 Defect diagram of the circuit board under the infrared and red light illumination combination of the preferred embodiment of the present invention.

[0043] Reference numerals: 11, top detection light box; 111, first box body; 1111, first light outlet; 1112, detection port; 112, left light source assembly; 113, right light source assembly; 114, top light source assembly; 115, beam splitter; 116, left diffuser plate; 117, right diffuser plate; 118, top diffuser plate; 12, backlight detection light box; 121, second box body; 1211, second light outlet; 1212, connection hole; 1213, arc adjustment groove; 122, backlight source assembly; 123, back diffuser plate; 13, detection camera; 131, line scan lens; 132, array camera; 14, scanning platform; 141, light transmission port; 15, circuit board. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0044] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present invention.

[0045] In the figures, units with similar structures are denoted by the same reference numerals.

[0046] In the terms of the present invention, words such as "first" and "second" are only for descriptive purposes, and cannot be understood as indicating or implying relative importance, nor as limiting the order of precedence.

[0047] Please refer to Figure 1 , in which Figure 1 is a schematic diagram of the overall structure of the first embodiment of the present invention.

[0048] The following is a preferred embodiment of a two-color illumination frame extraction detection system provided by the present invention that can solve the above technical problems.

[0049] A preferred embodiment of the two-color illumination frame extraction detection system provided by the present invention is: a two-color illumination frame extraction detection system, which includes a scanning platform 14, an illumination device, and a detection camera 13; the scanning platform 14 is used to support a circuit board 15, and the circuit board 15 is provided with through holes; the illumination device includes a top detection light box 11 and a backlight detection light box 12; wherein the top detection light box 11 is located above the scanning platform 14, and the top detection light box 11 is used to irradiate the top surface of the circuit board 15, and the top detection light box 11 includes a top white light module and a top infrared light module; the backlight detection light box 12 is located below the scanning platform 14, and the backlight detection light box 12 is used to irradiate the hole walls of the through holes of the circuit board 15, and the backlight detection light box 12 includes a back white light module and a back red light module. The detection camera 13 is located above the scanning platform 14, and the detection camera 13 collects an image of the circuit board 15 on the scanning platform 14 under the illumination of the illumination device.

[0050] Among them, the illumination device includes two illumination modes: a white-white light illumination combination and an infrared-red light illumination combination; when the illumination device adopts the white-white light illumination combination, the top white light module and the back white light module emit white light, and the detection camera 13 can detect scratches and stain defects on the surface of the circuit board 15; when the illumination device adopts the infrared-red light illumination combination, the top infrared light module emits infrared light, and the back red light module emits red light, and the detection camera 13 can detect concave defects on the surface of the circuit board 15.

[0051] A dual-color illumination frame extraction detection system of the present application conveys a circuit board 15 through a scanning platform 14. Through the collaborative work of a top detection light box 11 and a backlight detection light box 12, the illumination device irradiates the top surface and the through-hole wall of the circuit board 15 comprehensively, ensuring that the images collected by a detection camera 13 are clear and comprehensive. By integrating two illumination modes, a white-white light illumination combination and an infrared-red light illumination combination, it is possible to efficiently detect different types of defects. The white-white light illumination combination is suitable for detecting defects such as scratches and stains on the surface of the circuit board 15 under visible light, while the infrared-red light illumination combination is more adept at detecting defects such as depressions inside the circuit board 15 that are difficult to observe with ordinary white light, solving the limitations of a single illumination method in traditional detection methods, enabling the detection system to simultaneously detect defects such as scratches and stains on the surface of the circuit board 15 and hidden defects such as internal depressions, improving the comprehensiveness and accuracy of detection.

[0052] The light of the top detection light box 11 is used to detect the surface, and the light of the backlight detection light box 12 is used to detect the holes. White light is used to detect surface defects, and infrared is used to detect defects under the ink. When the top detection light box 11 uses infrared light to detect defects, it is better for the backlight detection light box 12 to use red light to feedback the defects of the holes (the defects inside the holes can be more clearly feedback relative to the white light background). Therefore, a dual-color illumination frame extraction detection system of the present application uses a combination of infrared + red light, and white + white light is convenient for users to directly observe the defects of the circuit board 15 with the naked eye.

[0053] The structure of the illumination device that can implement the above illumination combination is described as follows:

[0054] Combined with Figure 1 and Figure 2 , the top detection light box 11 in this embodiment includes a first box body 111, a left light source assembly 112, a right light source assembly 113, a top light source assembly 114, and a beam splitter 115. The first box body 111 is provided with a first light outlet 1111 facing the circuit board 15 and a detection port 1112 disposed opposite to the first light outlet 1111. The box body structure in this embodiment is generally square. The first light outlet 1111 is provided on the bottom wall of the first box body 111, and the detection port 1112 is provided on the top wall of the first box body 111. The included angle between the ray pointing from the center position of the first light outlet 1111 to the center position of the detection port 1112 and its projection on the plane where the scanning platform 14 is located is 80°. Here, for the convenience of installing various components inside the first box body 111, the first box body 111 can also be made into other shapes.

[0055] The left light source assembly 112, the right light source assembly 113, the top light source assembly 114, and the beam splitter 115 are all arranged inside the first box body 111. The left light source assembly 112 and the right light source assembly 113 are respectively located on both sides of the light outlet, and are used to irradiate the circuit board 15 from the side through the first light outlet 1111. The left light source assembly 112 is located on one side of the first box body 111 close to the first light outlet 1111. The left light source assembly 112 irradiates the circuit board 15 from one side, and the left light source assembly 112 includes a left white light module and a left infrared light module.

[0056] The right light source assembly 113 is located on one side of the first box body 111 close to the first light outlet 1111. The right light source assembly 113 is arranged opposite to the left light source assembly 112. The right light source assembly 113 irradiates the circuit board 15 from the other side, and the right light source assembly 113 includes a right white light module and a right infrared light module.

[0057] The beam splitter 115 is obliquely arranged between the first light outlet 1111 and the detection port 1112, and the beam splitter 115 is farther away from the first light outlet 1111 relative to the left light source assembly 112 and the right light source assembly 113. The beam splitter 115 is located on one side of the first box body 111 close to the detection port 1112. The beam splitter 115 can reflect the light emitted by the top detection light box 11 onto the circuit board 15, and at the same time can allow part of the light reflected by the circuit board 15 to pass through and enter the detection camera 13; the beam splitter 115 can allow part of the light to pass through while reflecting the light, which is beneficial to taking images of the circuit board 15.

[0058] The top light source assembly 114 is connected to the first box body 111. The top light source assembly 114 is located on one side of the first box body 111 close to the detection port 1112. The top light source assembly 114 is arranged opposite to the beam splitter 115. The light of the top light source assembly 114 is directed towards the beam splitter 115 and is reflected by the beam splitter 115 and then irradiates the circuit board 15. The top light source assembly 114 includes a top white light module and a top infrared light module. The top light source assembly 114 is used to make up for the missing light at the gap between the left light source assembly 112 and the right light source assembly 113.

[0059] The lights of the left light source assembly 112 and the right light source assembly 113 can respectively irradiate the circuit board 15 from the side, and can be used to detect the diffuse reflection surfaces on the circuit board 15. Diffuse reflection surfaces such as pads and ink surfaces on the circuit board 15 can diffusely reflect light. The light reflected by the circuit board 15 passes through the first light outlet 1111, the beam splitter 115, and the detection port 1112 in sequence and reaches the detection camera 13. The detection camera 13 captures the image to realize the scanning detection of the surface of the circuit board 15.

[0060] The light rays of the left light source assembly 112, the right light source assembly 113, and the top light source assembly 114 are obliquely irradiated onto the circuit board 15 through the first light outlet 1111. In the white light illumination mode, defects such as scratches and stains on the surface of the circuit board 15 are detected; in the infrared red light illumination mode, hidden defects such as depressions on the surface of the circuit board 15 are detected.

[0061] In addition, the top detection light box 11 further includes a left diffuser plate 116, a right diffuser plate 117, and a top diffuser plate 118. The left diffuser plate 116 is connected to the first box body 111, and the left diffuser plate 116 is arranged between the left light source assembly 112 and the first light outlet 1111; the right diffuser plate 117 is connected to the first box body 111, and the right diffuser plate 117 is arranged between the right light source assembly 113 and the first light outlet 1111; the left diffuser plate 116 and the right diffuser plate 117 are arranged oppositely, and the plane where the left diffuser plate 116 is located, the plane where the right diffuser plate 117 is located, and the plane where the first light outlet 1111 is located are arranged in a triangle.

[0062] The top diffuser plate 118 is located between the top light source assembly 114 and the beam splitter 115. The light rays at the position of the top light source assembly 114 pass through the top diffuser plate 118 and then act on the PCB through the beam splitter 115.

[0063] In this embodiment, the side diffuser plate corresponding to the left light source assembly 112 is the left diffuser plate 116, the side diffuser plate corresponding to the right light source assembly 113 is the right diffuser plate 117, and the side diffuser plate corresponding to the top light source assembly 114 is the top diffuser plate 118. By setting the left diffuser plate 116, the right diffuser plate 117, and the top diffuser plate 118, the light rays emitted by the left light source assembly 112, the right light source assembly 113, and the top light source assembly 114 can be converted into line light sources with relatively uniform light intensity at each position, which is beneficial for the detection of the circuit board 15 and can avoid misjudgment caused by different light intensities at each position.

[0064] The three side diffuser plates are respectively arranged corresponding to the three light source assemblies, and the light rays emitted by the left light source assembly 112, the right light source assembly 113, and the top light source assembly 114 can be converted into line light sources with relatively uniform light intensity at each position, which is beneficial for the detection of the surface of the circuit board 15 and can avoid misjudgment caused by different light intensities at each position.

[0065] The top diffuser plate 118 in this embodiment can be frosted glass, which has the same function as the diffuser plate for light homogenization; the remaining light directly acts on the PCB after passing through the diffuser plate or frosted glass. Since the diffuser plate is prone to bending when heated, the left diffuser plate 116 and the right diffuser plate 117 below are preferably made of two pieces of frosted glass for light diffusion. Further, the included angle between the left diffuser plate 116 and the first light outlet 1111 is between 5° - 45°. In this embodiment, the included angle between the left diffuser plate 116 and the first light outlet 1111 is preferably set to 40°.

[0066] The included angle between the right diffuser plate 117 and the first light outlet 1111 is between 20° and 60°. In this embodiment, it is preferably set that the included angle between the right diffuser plate 117 and the first light outlet 1111 is 36°. In this embodiment, it is preferably set that the included angle between the top diffuser plate 118 and the first light outlet 1111 is between 60° and 90°, and in this embodiment, it is preferably set that the included angle between the top diffuser plate 118 and the first light outlet 1111 is 80°.

[0067] The included angle between the plane where the beam splitter 115 is located and the plane where the first light outlet 1111 is located is between 30° and 50°. In this embodiment, it is preferably set that the included angle between the plane where the beam splitter 115 is located and the plane where the first light outlet 1111 is located is 45°.

[0068] Combined Figure 1 and Figure 3 The backlight detection light box 12 includes a second box body 121, a backlight source assembly 122 and a beam splitter 115; the second box body 121 is located below the scanning platform 14. The backlight detection light box 12 is provided with a second light outlet 1211 facing the circuit board 15. The backlight source assembly 122 is connected to the second box body 121. The light emitted by the backlight source assembly 122 irradiates the through-hole wall of the circuit board 15. The backlight source assembly 122 includes a back white light module and a back red light module; wherein, the light emitted by the backlight source assembly 122 irradiates the through-hole wall of the circuit board 15, and after being reflected by the circuit board 15, it passes through the beam splitter 115 and forms an image at the detection port 1112.

[0069] The backlight detection light box 12 is located below the light transmission port 141. The backlight detection light box 12 is used to emit light towards the circuit board 15, and there is an included angle between the light emitted by the backlight detection light box 12 and the straight line where the extension direction of the through-hole is located; the detection camera 13 is arranged on the ray pointing from the center position of the first light outlet 1111 to the center position of the detection port 1112, and the detection camera 13 is arranged towards the direction from the detection port 1112 to the first light outlet. The detection camera 13 is used to confirm whether the circuit board 15 is qualified according to the surface shadow image of the circuit board 15.

[0070] The backlight detection light box 12 further includes a back diffuser plate 123, and the back diffuser plate 123 is arranged between the backlight source assembly 122 and the light transmission port 141. The side diffuser plate corresponding to the backlight source assembly 122 is the back diffuser plate 123. The back diffuser plate 123 converts the light emitted by the backlight source assembly 122 into a line light source with relatively uniform light intensity at each position, which is beneficial to the detection of the circuit board 15, avoids misjudgment caused by different light intensities at each position, and improves the practicability of the structure of the backlight detection light box 12.

[0071] The included angle between the backlight diffuser plate 123 and the plane where the second light outlet 1211 is located is between 5° and 45°. Preferably, in this embodiment, the included angle between the backlight diffuser plate 123 and the plane where the second light outlet 1211 is located is 10°.

[0072] In this embodiment, the backlight assembly 122 is adjustably connected to the second box body 121.

[0073] Combined Figure 4 , the second box body 121 is provided with a connection hole 1212 and an arc-shaped adjustment groove 1213. The opening of the arc-shaped adjustment groove 1213 faces the connection hole 1212. The backlight assembly 122 is connected to the connection hole 1212 by a screw, and the backlight assembly 122 is adjustably connected to the arc-shaped adjustment groove 1213 by a screw, so that the backlight assembly 122 can be rotationally adjusted with the connection hole 1212 as the center, so that the backlight assembly 122 can be rotationally adjusted with the connection hole 1212 as the center.

[0074] The structure of the detection camera 13 in this embodiment will be described:

[0075] Combined Figure 1 , the detection camera 13 in this embodiment is arranged on the ray pointing from the center position of the first light outlet 1111 to the center position of the detection port 1112, and the detection camera 13 is arranged facing the direction from the detection port 1112 to the first light outlet 1111. Further, the detection camera 13 includes a line scan lens 131 and an array camera 132. The line scan lens 131 is located between the array camera 132 and the top detection light box 11. The light emitted by the top detection light box 11 irradiates the circuit board 15, and after being reflected by the circuit board 15, it passes through the first light outlet 1111 and the detection port 1112 in sequence, and enters the array camera 132 through the line scan lens 131, and then imaging is performed. In addition, in other embodiments, the detection camera 13 may also only include the array camera 132.

[0076] The working principle of a two-color illumination frame extraction detection system of the present utility model is as follows:

[0077] I. Preparation work.

[0078] Place the circuit board 15 to be detected on the scanning platform 14.

[0079] Prepare the lighting devices required for detection (including the top detection light box 11 and the backlight detection light box 12), and the detection camera 13.

[0080] II. Select the lighting mode.

[0081] Select the white-white light illumination combination or the infrared-red light illumination combination according to the detection requirements.

[0082] (1) White light illumination combination: The top white light module and the back white light module emit white light, which is used to detect surface defects such as scratches and stains on the circuit board 15.

[0083] (2) Infrared and red light illumination combination: The top infrared light module emits infrared light, and the back red light module emits red light, which is used to detect internal defects such as depressions on the circuit board 15.

[0084] III. Start the lighting device.

[0085] Start the top detection light box 11 and the backlight detection light box 12, activate the corresponding light source modules according to the selected lighting mode, ensure that all light source components work properly, and the light evenly irradiates the circuit board 15.

[0086] (1) When the white light illumination combination irradiates the circuit board 15, turn on the top white light modules of the four light source components (i.e., the left light source component 112, the right light source component 113, the top light source component 114, and the backlight source component 122) at the same time.

[0087] The white light line emitted by the left white light module of the left light source component 112 forms a line light source with relatively uniform illumination intensity at each position after passing through the left diffuser plate 116, and then irradiates the circuit board 15 through the first light outlet 1111. After being reflected by the circuit board 15, it enters the detection camera 13 through the first light outlet 1111, the beam splitter 115, and the detection port 1112 in sequence, completing the image acquisition process.

[0088] The white light line emitted by the right white light module of the right light source component 113 forms a line light source with relatively uniform illumination intensity at each position after passing through the right diffuser plate 117, and then irradiates the circuit board 15 through the first light outlet 1111. After being reflected by the circuit board 15, it enters the detection camera 13 through the first light outlet 1111, the beam splitter 115, and the detection port 1112 in sequence, completing the image acquisition process.

[0089] The white light line emitted by the top white light module of the top light source component 114 irradiates the circuit board 15 after passing through the top diffuser plate 118, the beam splitter 115, and the first light outlet 1111; after being reflected by the circuit board 15, it enters the detection camera 13 through the first light outlet 1111, the beam splitter 115, and the detection port 1112 in sequence, completing the image acquisition process.

[0090] The white light line emitted by the back white light module in the backlight source component 122 forms a line light source with relatively uniform illumination intensity at each position after passing through the back diffuser plate 123, and then irradiates the circuit board 15 through the second light outlet 1211. After being reflected by the hole wall of the through hole on the circuit board 15, it enters the detection camera 13 through the first light outlet 1111, the beam splitter 115, and the detection port 1112 in sequence, completing the image acquisition process.

[0091] (2)When the infrared and red light illumination combination irradiates the circuit board 15, the infrared light modules of the three light source components (i.e., the left light source component 112, the right light source component 113, and the top light source component 114) in the top detection light box 11 and the red light module of the backlight component 122 are turned on simultaneously.

[0092] The infrared light rays emitted by the left infrared light module of the left light source component 112 form a linear light source with relatively uniform illumination intensity at each position after passing through the left diffuser plate 116, and then irradiate the circuit board 15 through the first light outlet 1111. After being reflected by the circuit board 15, they enter the detection camera 13 in sequence through the first light outlet 1111, the beam splitter 115, and the detection port 1112, completing the imaging process.

[0093] The infrared light rays emitted by the right infrared light module of the right light source component 113 form a linear light source with relatively uniform illumination intensity at each position after passing through the right diffuser plate 117, and then irradiate the circuit board 15 through the first light outlet 1111. After being reflected by the circuit board 15, they enter the detection camera 13 in sequence through the first light outlet 1111, the beam splitter 115, and the detection port 1112, completing the imaging process.

[0094] The infrared light rays emitted by the top infrared light module of the top light source component 114 irradiate the circuit board 15 after passing through the top diffuser plate 118, the beam splitter 115, and the first light outlet 1111; after being reflected by the circuit board 15, they enter the detection camera 13 in sequence through the first light outlet 1111, the beam splitter 115, and the detection port 1112, completing the imaging process.

[0095] The red light rays emitted by the back red light module in the backlight component 122 form a linear light source with relatively uniform illumination intensity at each position after passing through the back diffuser plate 123, and then irradiate the circuit board 15 through the second light outlet 1211. After being reflected by the hole wall of the through hole on the circuit board 15, they enter the detection camera 13 in sequence through the first light outlet 1111, the beam splitter 115, and the detection port 1112, completing the imaging process.

[0096] IV. The detection camera 13 captures images.

[0097] The detection camera 13 is located above the scanning platform 14 and receives the light reflected by the circuit board 15 through the beam splitter 115. Under the action of the lighting device, the detection camera 13 starts to capture the image of the circuit board 15 on the scanning platform 14.

[0098] (1) In this embodiment, when there are no defects on the surface of the circuit board 15 collected under the white-white light illumination combination, it is manifested as uniform light emission on the surface of the collected circuit board 15. If there are scratches or stain defects on the surface of the collected circuit board 15, they are obvious under the white-white light illumination combination. As Figure 5 shown, in the circuit board image collected by the detection camera 13 under the white-white light illumination combination, the defects of scratches and stains on the surface of the circuit board are very obvious.

[0099] (2) In this embodiment, when there are no defects on the surface of the circuit board 15 collected under the infrared-red light illumination combination, it is manifested as uniform light emission on the surface of the collected circuit board 15. If there are concave defects on the surface of the collected circuit board 15, they are obvious under the infrared-red light illumination combination. As Figure 6 shown, in the circuit board image collected by the detection camera 13 under the infrared-red light illumination combination, the concave defects on the surface of the circuit board are very obvious.

[0100] When the through holes on the circuit board 15 are base material holes, light undergoes diffuse reflection inside the base material holes, and only a small amount of light can enter the camera array through the first light outlet 1111, the beam splitter 115, and the detection port 1112. The scanning imaging shows that the hole wall is dark; when the through holes on the circuit board 15 are electroplated holes, light undergoes specular reflection in the electroplated holes, and a large amount of light can enter the camera array through the first light outlet 1111, the beam splitter 115, and the detection port 1112. The scanning imaging shows that the inside of the hole is bright. By detecting the bright and dark changes of the through hole wall in the scanned image, it is possible to detect whether there are defects on the through hole wall. In this embodiment, when there are no defects on the wall surface of the through holes of the circuit board 15, it is manifested as uniform light emission inside the through holes of the collected circuit board 15. If there are defects on the through hole wall surface, such as ink deposition on the metal surface of the hole wall, or metal impurities deposited on the non-metal hole wall surface, then black dots will appear on the uniform reflective surface or reflective dots will appear on the non-reflective surface.

[0101] V. The control system performs image processing and analysis.

[0102] The collected image data is transmitted to the control system for processing and analysis.

[0103] The control system identifies defects in the image, such as scratches, stains, and concavities, through a preset algorithm.

[0104] It is determined whether the circuit board 15 is qualified according to the recognition result and confirmed by the user.

[0105] In this way, the working process of the dual-color illumination frame extraction detection system in this preferred embodiment is completed.

[0106] In this dual-color illumination frame extraction detection system, steps such as judging whether the circuit board 15 is qualified according to the recognition result are not particularly described as the innovation points of this application, but are applied to the dual-color illumination frame extraction detection system as existing technologies. After the control system receives the image data collected by the detection camera 13, it will be processed according to the existing image processing and analysis technologies. The focus of this application lies in the structural design of the dual-color illumination frame extraction detection system, the illumination method, and the optimization of the detection method to ensure the accuracy and efficiency of the detection.

[0107] In addition, in the dual-color illumination frame extraction detection system of this application, the white-white light illumination combination is used to detect surface defects, which is convenient for users to detect. The top white light module of the top detection light box 11 irradiates the surface defects of the detected circuit board surface, such as surface scratches, solder pads on the solder mask, exposed copper, depressions, protruding copper, whitening of the solder mask, broken solder mask bridges, open circuits, short circuits, etc. The back white light module of the backlight detection light box 12 irradiates the through-hole walls of the circuit board, which is convenient for maintenance personnel to observe the hole wall defects.

[0108] The infrared-red light illumination combination is mainly used to detect defects under the circuit board ink. The top infrared light module of the top detection light box 11 is used to detect defects under the surface ink of the circuit board, such as open circuits and short circuits under the ink, copper wires under the ink, foreign objects under the ink, etc. The back red light module of the backlight detection light box 12 irradiates the through-hole walls of the circuit board 15, and can better feedback the defects of the holes (the defects inside the holes can be more clearly feedback relative to the white light background).

[0109] At the same time, two illumination modes of the white-white light illumination combination and the infrared-red light illumination combination are set. Compared with using monochromatic light for detection, through the setting of two groups of detection light rays in this solution, the detection of most surface defects and ink defects on the circuit board surface and inside the holes is realized by using two-frame sub-frame detection, and the detection effect is better than that of monochromatic light detection. It also solves the problem that the combined brightness of white light and infrared light cannot be exposed, the combined brightness of white light and infrared light has limitations on the brightness of both lights, and the proportion of infrared light is prone to be too high, and the detection ability of using mixed light is limited to a certain extent.

[0110] In summary, although the present utility model has been disclosed above with preferred embodiments, the above preferred embodiments are not intended to limit the present utility model. Those of ordinary skill in the art can make various changes and modifications without departing from the spirit and scope of the present utility model. Therefore, the protection scope of the present utility model shall be subject to the scope defined by the claims.

Claims

1. A two-color illumination frame extraction detection system, characterized in that: include: A scanning platform, used to support a circuit board, wherein a light-transmitting port is provided at a position of the scanning platform corresponding to the circuit board, and the circuit board is provided with a through hole; A lighting device, comprising: A top detection light box, located above the scanning platform, for illuminating the top surface of the circuit board, the top detection light box comprising a top white light module and a top infrared light module; and A backlight detection light box, located below the light-transmitting port, for illuminating the through-hole wall of the circuit board, the backlight detection light box comprising a back white light module and a back red light module; An inspection camera is located above the scanning platform, and the inspection camera collects an image of the circuit board on the scanning platform under the illumination of the illumination device; and Wherein; the lighting device includes two lighting modes: a white light lighting combination and an infrared red light lighting combination; When the lighting device adopts the white-light lighting combination, the top white light module and the back white light module both emit white light, and the inspection camera can detect scratches and stains defects in the image of the circuit board; When the lighting device adopts an infrared and red light lighting combination, the top infrared light module emits infrared light, the back red light module emits red light, and the detection camera can detect the concave defects in the image of the circuit board.

2. The dual-color illumination frame extraction detection system according to claim 1, characterized in that: The top detection light box comprises: A first box body, wherein the first box body is provided with a first light outlet facing the circuit board and a detection outlet arranged opposite to the first light outlet; A left light source assembly is located inside the first housing and close to the first light outlet. The left light source assembly illuminates the circuit board from one side. The left light source assembly includes a left white light module and a left infrared light module. a right light source assembly, located inside the first housing and close to the first light outlet, the right light source assembly being arranged opposite to the left light source assembly, irradiating the circuit board from the other side, and comprising a right white light module and a right infrared light module; a spectroscope connected to the first housing, the spectroscope being tilted between the first light outlet and the detection outlet, and located inside the first housing near the detection outlet; and A top light source assembly is connected to the first housing and is located inside the first housing on one side close to the detection port. The top light source assembly is arranged relative to the spectroscope. The light from the top light source assembly is directed toward the spectroscope and illuminates the circuit board after being reflected by the spectroscope. The top light source assembly includes a top white light module and a top infrared light module.

3. The dual-color illumination frame extraction detection system according to claim 2, characterized in that: The backlight detection light box comprises: The second box is provided with a second light outlet facing the circuit board; A backlight source assembly is connected to the second housing and is used to emit light to illuminate the through-hole wall of the circuit board. The backlight source assembly includes the back white light module and the back red light module. The light emitted by the backlight source assembly is irradiated onto the through-hole wall of the circuit board, and after being reflected by the circuit board, passes through the spectroscope and forms an image at the detection port.

4. The dual-color illumination frame extraction detection system according to claim 2, characterized in that: The top detection light box also includes: a left diffuser plate connected to the first housing, the left diffuser plate being disposed between the left light source assembly and the first light outlet; and A right diffuser plate connected to the first box, and arranged between the right light source assembly and the first light outlet; The left light diffuser plate and the right light diffuser plate are arranged opposite to each other, and the plane where the left light diffuser plate is located, the plane where the right light diffuser plate is located, and the plane where the first light outlet is located are arranged in a triangle.

5. The dual-color illumination frame extraction detection system according to claim 2, characterized in that: The top detection light box also includes a top light diffusion plate, and the top light diffusion plate is located between the top light source assembly and the beam splitter.

6. The dual-color illumination frame extraction detection system according to claim 3, characterized in that: The top detection light box further comprises a back light scattering plate, and the back light scattering plate is arranged between the backlight source assembly and the second light outlet.

7. The dual-color illumination frame extraction detection system according to claim 3, characterized in that: The backlight source assembly is adjustably connected to the second box.

8. The dual-color illumination frame extraction detection system according to claim 7, characterized in that: The second box body is provided with a connecting hole and an arc-shaped adjusting groove, wherein the arc-shaped adjusting groove is located above the connecting hole and the opening of the arc-shaped adjusting groove faces the connecting hole. The backlight source assembly is connected to the connection hole via screws, and the backlight source assembly is adjustably connected to the arc-shaped adjustment groove via screws, so that the light source assembly can be rotated and adjusted around the connection hole.

9. The dual-color illumination frame extraction detection system according to claim 3, characterized in that: The angle between the plane where the beam splitter is located and the plane where the second light outlet is located is between 30° and 50°.

10. The dual-color illumination frame extraction detection system according to claim 6, characterized in that: The angle between the back light diffuser plate and the plane where the second light outlet is located is between 5° and 45°.

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