Lamp box and detection device

Abstract

The utility model relates to the technical field of light source detection, and discloses a light box and a detection device.The light box comprises a box body, a first light source module and an arc-shaped dimming module, the box body is provided with a light path channel in the first direction, the two opposite sides of the light path channel form a collection port and a light outlet respectively, the first light source module is arranged in the box body, and the arc-shaped dimming module is arranged in the box body. The arc-shaped dimming module is arranged at the light outlet, the middle of the arc-shaped dimming module is arched relative to the two ends of the arc-shaped dimming module in the direction from the light outlet to the collection port, and light emitted from the first light source module is emitted to the arc-shaped dimming module and is emitted to an object to be detected after being subjected to diffuse reflection of the arc-shaped dimming module. Light emitted by the first light source module is diffused uniformly after being subjected to diffuse reflection of the arc-shaped dimming module, so that the angles of the light are richer, the light at different angles can be provided to uniformly irradiate the surface of the to-be-detected object, high-definition imaging of a non-mirror area of the to-be-detected object is facilitated, the contrast ratio and the chromatic aberration value of imaging are enhanced, and the detection accuracy is improved. And missing detection caused by insufficient chromatic aberration is avoided.

Description

Technical Field

[0001] This utility model relates to the field of light source detection technology, and in particular to a light box and detection device. Background Technology

[0002] During the production of PCBs (Printed Circuit Boards), defects are often generated. These defects can easily affect the performance, quality, and safety of the PCBs. Therefore, optical inspection equipment is usually required to detect these defects. During inspection, the light source of the optical inspection equipment provides illumination to obtain an optical image of the PCB, and then the presence of appearance defects is determined based on this image.

[0003] However, in existing optical inspection equipment, the light source of the optical inspection equipment cannot achieve high resolution and recognition of optical imaging of some PCB circuit boards, which can easily lead to missed detection of appearance defects of PCB circuit boards. Utility Model Content

[0004] The present invention aims to provide a light box and a detection device to solve the technical problem that the light source of the existing optical detection equipment cannot achieve high resolution and recognition of optical imaging of some PCB circuit boards, which easily leads to the missed detection of appearance defects of PCB circuit boards.

[0005] The present invention addresses its technical problem by providing the following technical solution: a light box, comprising:

[0006] The housing has an optical path channel along a first direction, and the two opposite ends of the optical path channel form a collection port and an output port, respectively.

[0007] A first light source module is disposed in the housing;

[0008] An arc-shaped dimming module is disposed at the light outlet. The middle part of the arc-shaped dimming module arches upwards relative to both ends of the arc-shaped dimming module in the direction from the light outlet to the collection port. Light emitted from the first light source module can be directed toward the arc-shaped dimming module and diffusely reflected by the arc-shaped dimming module before being directed toward the object to be detected.

[0009] In this embodiment, the arc-shaped dimming module can change the direction and distribution of light, thereby modulating the angle and homogenizing the light. The light emitted by the first light source module is diffused and uniformly diffused after passing through the arc-shaped dimming module. The arc-shaped dimming module has a good modulation and homogenization effect on the light, making the angle of the light more diverse. This allows light from different angles to uniformly illuminate the surface of the object to be inspected, which is beneficial for high-definition imaging of non-mirror areas of the object to be inspected (such as the solder mask layer of a PCB circuit board), enhancing the contrast and color difference values ​​of the image, improving the resolution and recognition of the image, and avoiding missed detections due to insufficient color difference. In addition, the arc-shaped dimming module occupies less space, which can save internal space of the cabinet and improve the structural compactness.

[0010] In some embodiments, the arc-shaped dimming module includes two symmetrically arranged arc-shaped dimming plates, with an opening between the two arc-shaped dimming plates, and the opening is respectively positioned opposite the light output port and the light acquisition port.

[0011] In this embodiment, the two arc-shaped dimming plates are symmetrically arranged relative to the optical path channel, making the light output of multiple light source modules paired with the two arc-shaped dimming plates more uniform, which facilitates further improvement in the resolution and recognition of the image of the object under test. An opening is formed between the two arc-shaped dimming plates, which allows light to pass through, enabling the camera module above the acquisition port to acquire the image of the object under test without obstruction, avoiding the arc-shaped dimming module itself from blocking the line of sight and ensuring the quality of image acquisition.

[0012] In some embodiments, the first light source module includes two first light source units and two second light source units. The two first light source units are respectively disposed on opposite sides of the arc-shaped dimming module along the second direction, and the two second light source units are respectively disposed on opposite sides of the arc-shaped dimming module along the second direction. The light-emitting surfaces of the first light source units and the second light source units both face the arc-shaped dimming module.

[0013] In this embodiment, the two first light source units and the two second light source units can form four relatively independent optical path channels. By adjusting the brightness and brightness ratio of each first light source unit and each second light source unit, various combined lighting methods can be achieved to improve the color difference value and contrast of different appearance defects, thereby meeting the imaging requirements of high resolution and high recognition of the object to be inspected.

[0014] In some embodiments, the second light source unit is disposed on the side of the first light source unit near the acquisition port, the angle between the light angle provided by the first light source unit and the horizontal direction is between 0° and 30°, and the angle between the light angle provided by the second light source unit and the horizontal direction is between 45° and 70°.

[0015] In this embodiment, the first light source unit provides light at an angle of 0-30 degrees to the horizontal. The light emitted by the first light source unit is homogenized and modulated by an arc-shaped dimming plate before illuminating the surface of the object to be inspected, forming diffuse reflected light for dark-field imaging with uniform illumination and a relatively low angle. For example, when inspecting defects on a PCB circuit board, the relatively low angle of light provided by the first light source unit is beneficial for forming low-angle uniform illumination, suitable for detecting solder resist scratches, abrasions, and flatness defects. The second light source unit provides light at an angle of 45-70 degrees to the horizontal. The light emitted by the second light source unit is homogenized and modulated by an arc-shaped dimming plate before illuminating the surface of the object to be inspected, forming diffuse reflected light for dark-field imaging with uniform illumination and a relatively high angle. For example, when inspecting defects on a PCB circuit board, the higher angle of light provided by the second light source unit is beneficial for magnifying defect features, improving defect color difference values ​​and contrast, suitable for detecting solder resist scratches, oil accumulation, unevenness, and other defects.

[0016] In addition, by adjusting the brightness and off state of each first light source unit and each second light source unit, various combined lighting methods can be achieved to improve the color difference value and contrast of different appearance defects, thereby meeting the imaging requirements of high resolution and high recognition of the object to be inspected.

[0017] In some embodiments, both the first light source unit and the second light source unit include a first light emitter, which is a white LED bead or an infrared LED bead.

[0018] In this embodiment, the first light emitter can be a white LED, which can provide warm or cool color temperature white light, or an infrared LED, which can provide near-infrared light. Different types of LEDs can be flexibly selected to adapt to different circuit board types. Furthermore, when a near-infrared LED is selected as the first light emitter, the infrared light emitted by the infrared LED can penetrate the solder resist layer, such as ink, thereby detecting open circuits, short circuits, foreign objects, and oxidation defects under the solder resist layer.

[0019] In some embodiments, the housing includes a top plate and a bottom plate arranged opposite to each other. The top plate has the collection port, and the bottom plate has two pieces. The two bottom plates are arranged at intervals to form the light outlet, and the two arc-shaped dimming plates are respectively disposed on the corresponding bottom plates.

[0020] The base plate is a reflector plate used to reflect light that is incident on it.

[0021] In this embodiment, some of the light emitted by the first light source module, especially the light emitted by the first light source unit, will be scattered onto the base plate. The base plate will reflect this part of the light, thus achieving secondary utilization, improving light efficiency, and enhancing lighting intensity.

[0022] In some embodiments, the light box further includes a second light source module and a reflective module, wherein the second light source module is located on the side of the first light source module closer to the acquisition port, and the reflective module is inclinedly disposed at the optical path channel, so that the light emitted from the second light source module can be reflected by the reflective component and directed to the light outlet.

[0023] In this embodiment, the mirror area of ​​the device under test requires vertical projection light illumination. At this time, the second light source module and the anti-transmission module can be used in combination. The light emitted from the second light source module is refracted by the anti-transmission module and then illuminates in a roughly vertically downward direction, thereby providing roughly vertical illumination light to the mirror area of ​​the device under test. This minimizes the brightness changes caused by angle deviation, thereby obtaining a high-definition and recognizable image.

[0024] In some embodiments, the second light source module includes a second substrate and a second light emitter arranged in an array on one side of the second substrate, wherein the width of the second substrate is twice or more the width of the opening.

[0025] In this embodiment, the width of the second substrate is twice or more the width of the opening, making the size of the second substrate larger. The larger light-emitting surface effectively expands the aperture angle of the illumination, so that light can illuminate the object being inspected from more angles. For areas with uneven surfaces on the surface of the object being inspected, such as uneven metal pads caused by the tin plating process on PCB circuit boards, the larger light-emitting surface, through its uniform and large-area illumination distribution, can ensure that the reflected light from the uneven areas is uniformly received by the camera module, avoiding local dark areas caused by uneven areas, and preventing normal unevenness of the tin-plated board from being misjudged as defects.

[0026] In some embodiments, the light box further includes a dimming element disposed between the second substrate and the reflective module, wherein the dimming element is any one of a light-diffusing plate, a light-concentrating lens, a light guide plate, or a modulation film.

[0027] For example, when the light-adjusting component is selected as a light-diffusing plate, it can achieve light with a soft angle. When the light-adjusting component is a condenser lens, a light guide plate, or a modulation film, it can achieve parallel light or converging light with a converged angle, thus meeting the detection needs in different scenarios.

[0028] In some embodiments, the housing includes two oppositely arranged cover plates, the cover plates being reflective plates;

[0029] The anti-reflective module includes two mounting plates arranged opposite each other and an anti-reflective sheet. The two ends of the mounting plates are fixedly connected to the corresponding cover plates. The mounting plates have a sliding groove along their length. The anti-reflective sheet is located between the two mounting plates and installed in the sliding groove.

[0030] In this embodiment, when it is necessary to remove the reflective sheet, only one of the cover plates needs to be removed, and then the reflective sheet can be taken out from the slide groove without disassembling the mounting plate, which is convenient, quick, and saves time and effort.

[0031] Furthermore, the cover plate has high reflectivity, which enables it to effectively reflect light and reduce light signal loss. This compensates for the insufficient illumination in the edge areas of the first and second light source modules, ensuring a more uniform light distribution.

[0032] In some embodiments, the light box further includes a first light-absorbing element and a second light-absorbing element;

[0033] The first light-absorbing element is disposed on the inner side wall of the housing, and the first light-absorbing element is located on the side of the anti-transparency module away from the second light source module. The second light-absorbing element is disposed on the inner top wall of the housing.

[0034] In this embodiment, the first light-absorbing element and the second light-absorbing element are used to absorb the energy of the light transmitted from the light-transmitting sheet and significantly reduce the intensity of stray light. This effectively prevents the light reflected back from the inner side wall and inner top wall of the box from interfering with the imaging of the camera module and ensures the imaging quality.

[0035] The present invention also addresses its technical problem by employing the following technical solution: providing a detection device, including the lightbox described in any of the above embodiments; and

[0036] A camera module is disposed at the acquisition port and is used to acquire image information of the object to be detected.

[0037] Since the detection device includes the lightbox as described in any of the above embodiments, it also has the beneficial effects of any of the above embodiments. The specific beneficial effects have been described in detail above and will not be repeated here. Attached Figure Description

[0038] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0039] Figure 1 This is a three-dimensional structural schematic diagram of the detection device in the embodiments of this application;

[0040] Figure 2 This is a three-dimensional structural diagram of the light box in the embodiments of this application;

[0041] Figure 3 This is a cross-sectional structural diagram of the light box in an embodiment of this application;

[0042] Figure 4 This is a schematic diagram of the internal structure of the light box in an embodiment of this application;

[0043] Figure 5 This is a three-dimensional structural diagram of the light box after removing the top and side panels in the embodiment of this application;

[0044] Figure 6 This is a three-dimensional structural diagram of the first light source unit in the embodiments of this application;

[0045] Figure 7 This is a three-dimensional structural diagram of the second light source module in the embodiments of this application;

[0046] Figure 8 This is a three-dimensional structural diagram of the anti-reflective module in the embodiments of this application.

[0047] Explanation of reference numerals in the attached figures:

[0048] 100. Lightbox; 10. Cabinet; 11. Optical path channel; 110. Acquisition port; 111. Light output port; 12. Top plate; 13. Bottom plate; 130. Groove; 14. Side plate; 15. Cover plate; 150. Interface; 20. First light source module; 21. First light source unit; 210. First substrate; 211. First light emitter; 212. First heat sink; 213. First cooling fan; 22. Second light source unit; 30. Arc 31. Arc-shaped dimming module; 310. Opening; 40. Second light source module; 41. Second substrate; 42. Second light emitter; 43. Dimming component; 44. Second heat sink; 45. Second cooling fan; 50. Reflective module; 51. Mounting plate; 510. Slide groove; 52. Reflective sheet; 60. First light absorber; 70. Second light absorber; 200. Detection device; 201. Camera module; 202. Transmission module. Detailed Implementation

[0049] To facilitate understanding of this utility model, a more detailed description is provided below with reference to the accompanying drawings and specific embodiments. It should be noted that when an element is described as "connected" to another element, it can be directly on the other element, or one or more intermediate elements may exist between them. The terms "upper," "lower," "left," "right," "upper end," "lower end," "top," and "bottom," etc., used in this specification, indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and 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, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0050] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of the invention.

[0051] PCB inspection is divided into AVI (Area of ​​Visual Interest) inspection and AOI (Area of ​​Interest) inspection. During AVI inspection, PCBs typically have both a solder resist layer (ink) and metal pads. PCB manufacturing processes include OSP (Organic Solderability Preservative), plating, and electroless soldering. After OSP processing and some electroless soldering processes, the gloss of the metal pads decreases, and may even show slight blackening in certain areas. This results in the color difference between the metal pads and the solder resist layer not being effectively separated. Current optical inspection equipment has low resolution and recognition capabilities, making it difficult to effectively identify these two areas, leading to missed and false detections of PCB surface defects.

[0052] In addition, due to the tin plating process, the surface of the metal pads will have irregular unevenness. Currently, the light source of optical inspection equipment will image obvious black areas on some PCBs with tin plating process, which will be misidentified by the optical inspection equipment as appearance defects (this area is actually a normal area in the production process). This will increase the false alarm rate of the optical inspection equipment and affect the accuracy of inspection.

[0053] To address the aforementioned deficiencies in existing technologies, this utility model provides a lightbox and detection device. The light emitted from a first light source module is diffused and homogenized by an arc-shaped dimming module. The light emitted from the first light source module is diffused and uniformly diffused by the arc-shaped dimming module, resulting in a wider range of light angles. This allows light from different angles to uniformly illuminate the surface of the object being detected, facilitating high-definition imaging of non-mirror areas (such as the solder mask layer on a PCB circuit board), enhancing contrast and color difference values, improving resolution and recognizability, and avoiding... To avoid missed detections due to insufficient color difference, the second light source module has a larger emitting surface. This larger emitting surface effectively expands the aperture angle of the illumination, allowing light to reach the object being inspected from more angles. For areas with uneven surfaces (such as uneven metal pads caused by the tin plating process on PCB boards), the larger emitting surface, through its uniform and large-area illumination distribution, ensures that the reflected light from these uneven areas is evenly received by the camera module, avoiding localized dark areas caused by uneven surfaces and preventing normal unevenness on the tin-plated board from being misjudged as defects.

[0054] Please see Figures 1 to 4 ,in, Figure 3 The dashed line indicates the direction of optical path channel 11, and the dotted line indicates the direction of optical propagation.

[0055] This utility model embodiment provides a light box 100, including a box body 10, a first light source module 20, and an arc-shaped dimming module 30. The box body 10 is provided with a light path channel 11 along a first direction X (vertical direction). A collection port 110 and a light output port 111 are formed on opposite sides of the light path channel 11, respectively. The first light source module 20 is disposed in the box body 10, and the arc-shaped dimming module 30 is disposed at the light output port 111. The middle part of the arc-shaped dimming module 30 arches relative to the two ends of the arc-shaped dimming module 30 along the direction from the light output port 111 to the collection port 110. The light emitted from the first light source module 20 can be directed to the arc-shaped dimming module 30 and diffusely reflected by the arc-shaped dimming module 30 before being directed to the object to be detected.

[0056] like Figure 1As shown, the light box 100 can cooperate with the camera module 201 to detect the object to be detected. The camera module 201 can be a CCD (Charge-Coupled Device) camera, and the object to be detected can be a PCB circuit board, but is not limited to this. For example, the object to be detected can also be a flexible circuit board, semiconductor wafer, etc. During the detection process, the object to be detected can be placed horizontally below the light box 100 and corresponding to the position of the light outlet 111, that is, below the arc-shaped dimming module 30. The camera module 201 can be set above the light box 100 and corresponding to the position of the acquisition port 110. The camera module 201 is used to receive the light reflected by the object to be detected, thereby forming an image of the object to be detected.

[0057] The housing 10 defines an optical path channel 11 along a first direction X. The first direction X can be a vertical direction, meaning the optical path channel 11 is set in a vertical direction and is used to allow light to pass through. The upper end of the optical path channel 11 forms a collection port 110, and the lower end of the optical path channel 11 forms a light exit port 111.

[0058] The first light source module 20 is installed in the housing 10, and the arc-shaped dimming module 30 is located at the light outlet 111. The first light source module 20 can be used to provide bypass illumination light. The arc-shaped dimming module 30 has an arc-shaped structure, and the top of the arc-shaped dimming module 30 arches towards the light outlet 110, making it easier for the light emitted by the first light source module 20 to directly hit the surface of the arc-shaped dimming module 30. The arc-shaped dimming module 30 can change the direction and distribution of light, and has a good modulation and homogenization effect on light, playing a role in... The light source module 20 modulates the angle of light and homogenizes the light. After being diffusely reflected by the arc-shaped dimming module 30, the light is evenly diffused, making the angle of light more diverse. This allows diffusely reflected light from different angles to evenly illuminate the surface of the object to be tested, which is beneficial for high-definition imaging of the non-mirror areas of the object to be tested, enhances the contrast and color difference of the image, and makes the image information of the object to be tested acquired by the camera module 201 clearer. This improves the resolution and recognition of the image of the object to be tested and avoids missed detection due to insufficient color difference.

[0059] For example, for PCBs processed by OSP or partially tinned, the arc-shaped dimming module 30 diffuses and homogenizes the light emitted by the first light source module 20, providing diffused light at different angles to illuminate the PCB surface. This enhances the color contrast between the metal pads and the solder resist layer, improves the resolution and recognition of the PCB image, and avoids missed detections due to insufficient color difference between the metal pads and the solder resist layer. It can accurately detect defects such as scratches, cracks, bubbles, and missing prints in the solder resist layer, thereby ensuring the accuracy of PCB defect detection.

[0060] In addition, the curved dimming module 30 occupies less space (compared to the hemispherical structure of a traditional dome light source), which can save internal space of the cabinet 10 and improve the structural compactness.

[0061] In some embodiments, such as Figure 3 and Figure 4 As shown, the arc-shaped dimming module 30 includes two symmetrically arranged arc-shaped dimming plates 31, with an opening 310 formed between the two arc-shaped dimming plates 31. The opening 310 is respectively positioned opposite the light output port 111 and the collection port 110.

[0062] The two arc-shaped dimming plates 31 are symmetrically arranged relative to the optical path channel 11. The first light source module 20 may include multiple light source modules. The multiple light source modules can be located on opposite sides of the arc-shaped dimming module 30 along the second direction Y (width direction of the housing 10), so that the light output after the multiple light source modules are matched with the two arc-shaped dimming plates 31 is more uniform, which is conducive to further improving the resolution and recognition of the image of the object to be detected.

[0063] An opening 310 is formed between the two curved dimming plates 31, which allows light to pass through, so that the camera module 201 above the acquisition port 110 can acquire the image of the object to be detected without obstruction through the opening 310, avoiding the curved dimming plates 31 from blocking the line of sight and ensuring the image acquisition quality.

[0064] In some embodiments, the curved dimming plate 31 can be a curved acrylic plate. The curved acrylic plate has a good homogenization and diffusion effect on light. The light emitted by the first light source module 20 is diffused uniformly after being diffused by the curved acrylic plate and is directed toward the surface of the object to be tested, thereby enhancing the difference in imaging brightness of the object to be tested and improving the resolution and recognition of the imaging of the object to be tested.

[0065] Optionally, the surface of the curved acrylic sheet can be frosted or sanded to facilitate diffuse reflection and refraction of light when it passes through the surface of the curved acrylic sheet, thereby ensuring uniform diffusion of light and producing diffused light with richer angles and more uniformity.

[0066] In other embodiments, the curved dimming plate 31 may also be a curved Fresnel lens, a curved light guide plate, or a curved light homogenizing plate 43 (with modulation texture), etc. These optical devices can all play the role of modulating the angle of light and homogenizing light, providing richer and more uniform diffuse reflected light to illuminate the object to be tested.

[0067] In some embodiments, the first light source module 20 includes two first light source units 21 and two second light source units 22. The two first light source units 21 are respectively disposed on opposite sides of the arc-shaped dimming module 30 along the second direction Y, and the two second light source units 22 are respectively disposed on opposite sides of the arc-shaped dimming module 30 along the second direction Y. The light-emitting surfaces of the first light source units 21 and the second light source units 22 both face the arc-shaped dimming module 30.

[0068] like Figure 3 As shown, in this embodiment, on the left side of the arc-shaped dimming module 30 (with... Figure 3 (Taking the viewing angle as an example) A first light source unit 21 and a second light source unit 22 are provided. A first light source unit 21 and a second light source unit 22 are also provided on the right side of the arc-shaped dimming module 30. In this way, the two first light source units 21 and the two second light source units 22 can form four relatively independent optical path channels 11. By adjusting the brightness and brightness ratio of each first light source unit 21 and each second light source unit 22, various combined lighting methods can be achieved to improve the color difference value and contrast of different appearance defects, and meet the imaging requirements of high resolution and high recognition of the object to be inspected.

[0069] It is understood that in other embodiments, the first light source module 20 may also include more or fewer light source modules.

[0070] In some embodiments, the second light source unit 22 is disposed on the side of the first light source unit 21 near the acquisition port 110. The angle between the light angle provided by the first light source unit 21 and the horizontal direction is between 0° and 30°, and the angle between the light angle provided by the second light source unit 22 and the horizontal direction is between 45° and 70°. The horizontal direction is the direction of the plane containing the second direction Y and the third direction Z.

[0071] like Figure 3 and Figure 4 As shown, the first light source unit 21 is located inside the housing 10 and near the bottom side of the housing 10. The second light source unit 22 can be located directly above or diagonally above the first light source unit 21. The two first light source units 21 are symmetrically arranged with respect to the arc-shaped dimming module 30, and the two second light sources are symmetrically arranged with respect to the arc-shaped dimming module 30 to improve the uniformity of illumination.

[0072] The first light source unit 21 provides light at an angle of 0 to 30 degrees to the horizontal direction. The light emitted by the first light source unit 21 is homogenized and modulated by the arc-shaped dimming plate 31 and then illuminates the surface of the object to be inspected, forming diffuse reflected light with uniform illumination and a relatively low angle for dark field imaging. For example, when inspecting defects on a PCB circuit board, the relatively low angle of light provided by the first light source unit 21 is beneficial for forming low-angle uniform illumination, which is suitable for detecting solder resist scratches, abrasions, and flatness defects.

[0073] The second light source unit 22 provides light at an angle of 45-70 degrees to the horizontal direction. The light emitted by the second light source unit 22 is homogenized and modulated by the arc-shaped dimming plate 31 and then illuminates the surface of the object to be inspected, forming diffuse reflected light for dark field imaging with uniform illumination and a relatively high angle. For example, when inspecting defects on PCB circuit boards, using the second light source unit 22 to provide light at a higher angle is beneficial for magnifying defect features, improving defect color difference values ​​and contrast, and is suitable for detecting defects such as solder resist scratches, oil accumulation, and unevenness.

[0074] In actual PCB circuit board defect detection, by adjusting the brightness and off state of each first light source unit 21 and each second light source unit 22, a variety of combined lighting methods can be achieved to improve the color difference value and contrast of different appearance defects, thereby meeting the imaging requirements of high resolution and high recognition of PCB circuit boards.

[0075] For example, if the light intensity is insufficient after the second light source unit 22 is turned on, the first light source module 21 can be turned on to supplement the light intensity and increase the imaging effect, thereby improving the resolution and recognition of the image.

[0076] In some embodiments, the housing 10 includes a top plate 12 and a bottom plate 13 disposed opposite to each other. The top plate 12 has a collection port 110, and the bottom plate 13 has two pieces. The two bottom plates 13 are spaced apart and form a light outlet 111. Two arc-shaped dimming plates 31 are respectively disposed on the corresponding bottom plates 13. The bottom plates 13 can be used to reflect the light irradiated onto the bottom plates 13.

[0077] Specifically, some of the light emitted by the first light source module 20, especially the light emitted by the first light source unit 21, will be scattered onto the base plate 13. The base plate 13 will reflect this part of the light, thus making it usable again, improving light efficiency and enhancing lighting intensity.

[0078] Alternatively, the base plate 13 may be made of a high reflectivity material to improve reflectivity; for example, the base plate 13 may be made of mirror aluminum.

[0079] Please see Figure 3 , Figure 4 and Figure 5In some embodiments, the housing 10 further includes two oppositely arranged side plates 14 and two oppositely arranged cover plates 15. The two side plates 14 are respectively connected to opposite sides of the top plate 12, and the two side plates 14 and the top plate 12 form a roughly "U" shape. Optionally, the top plate 12 and the two side plates 14 can be integrally formed. Two bottom plates 13 are respectively connected to the ends of the corresponding side plates 14 away from the top plate 12, and two cover plates 15 are respectively disposed at opposite ends of the top plate 12 along its length.

[0080] In some embodiments, the arc-shaped dimming plate 31 is fixedly connected to two cover plates 15 at opposite ends along its length. For example, the arc-shaped dimming plate 31 can be fixedly connected to the cover plates 15 by means of plug-in or screw connection to ensure assembly reliability.

[0081] Optionally, the base plate 13 is provided with a groove 130 corresponding to the arc-shaped dimming plate 31 along its length direction, and the arc-shaped dimming plate 31 is engaged in the groove 130 to ensure assembly accuracy.

[0082] In some embodiments, the two ends of the first light source unit 21 are fixedly connected to the two cover plates 15 respectively. For example, the first light source unit 21 can be fixedly connected to the cover plate 15 by means of plugging, screwing or other methods to ensure assembly reliability.

[0083] Please see Figure 6 In some embodiments, both the first light source unit 21 and the first light source unit 22 include a first light emitter 211, which is a white LED or an infrared LED.

[0084] The first light source can be a white LED, which can provide warm or cool color temperature white light, or an infrared LED, which can provide near-infrared light. Different types of LEDs can be flexibly selected to suit different circuit board types. Optionally, the first light source 211 uses an infrared LED. The infrared light emitted by the infrared LED can penetrate the solder resist layer (such as ink), thereby enabling non-contact detection of the internal structure of the PCB circuit board. This can effectively identify whether there are short circuits, foreign matter residues, or oxidation problems inside the PCB circuit board, significantly improving the accuracy and reliability of defect detection.

[0085] In some embodiments, the first light source unit 21 further includes a first substrate 210, and a first light emitter 211 is disposed on one side of the first substrate 210. Optionally, the first substrate 210 may be an aluminum substrate, and the first light emitter 211 may be arranged linearly along the length of the aluminum first substrate 210 or arranged in an array on the first substrate 210.

[0086] In some embodiments, the first light source unit 21 further includes a first heat sink 212, which is disposed on the side of the first substrate 210 away from the first light emitter 211. The first heat sink 212 may be a metal plate with good thermal conductivity. For example, the first heat sink 212 may be configured as a serrated aluminum plate to improve thermal conductivity.

[0087] Optionally, the first light source unit 21 further includes a first cooling fan 213. The first cooling fan 213 is disposed on the side of the first heat sink 212 away from the first substrate 210. There may be multiple first cooling fans 213, which are spaced apart along the length of the first heat sink 212 to improve heat dissipation efficiency.

[0088] It is understandable that the structure and installation method of the second light source unit 22 can be the same as that of the first light source unit 21, and will not be described in detail here.

[0089] Please refer to the following: Figure 4 , Figure 7 and Figure 8 In some embodiments, the light box 100 also includes a second light source module 40 and a reflective module 50. Both the second light source module 40 and the reflective module 50 are disposed in the housing 10. The second light source module 40 is disposed on the side of the first light source module 20 near the acquisition port 110, and the reflective module 50 is disposed at an angle at the optical path channel 11. The light emitted from the second light source module 40 can be directed toward the reflective module 50 and reflected by the reflective module 50 before being directed toward the light outlet 111.

[0090] like Figure 4 As shown, the second light source module 40 can be positioned directly above or diagonally above the first light source module 20. The two opposite ends of the second light source module 40 are fixedly connected to the two cover plates 15 respectively. For example, the second light source module 40 can be fixedly connected to the cover plates 15 by means of plug-in or screw connection to ensure assembly reliability.

[0091] The anti-reflection module 50 has a certain light reflection and light transmission capability. The light emitted by the second light source 42 can be refracted by the anti-reflection module 50 and directed vertically toward the object to be tested. At the same time, the light reflected back from the object to be tested can pass through the anti-reflection module 50 and be directed toward the camera module 201.

[0092] For the mirror area of ​​the test piece, vertical projection light is required. At this time, the second light source module 40 and the anti-transmission module 50 can work together to provide roughly vertical illumination light to the mirror area of ​​the test piece, which minimizes the brightness change caused by angle deviation, thereby obtaining a high-definition and recognizable image.

[0093] In some embodiments, the second light source module 40 includes a second substrate 41 and second light emitters 42 arranged in an array on one side of the second substrate 41, wherein the width of the second substrate 41 is twice or more the width of the opening 310.

[0094] The second light source module 40 includes a second substrate 41 and a plurality of second light emitters 42. The plurality of second light emitters 42 can be arranged in an array uniformly on the second substrate 41. The width of the second substrate 41 (the dimension of the second substrate 41 in the vertical direction) is twice or more the width of the opening 310. For example, when the width of the opening 310 is 25 mm, the width of the second substrate 41 can be configured to be greater than or equal to 50 mm to provide a larger light-emitting surface. Optionally, the second substrate 41 can be an aluminum substrate, and the second light emitters 42 can be LED chips. The LED chips can be white LED chips or other colored LED chips.

[0095] The larger light-emitting surface effectively expands the aperture angle of the illumination, allowing light to reach the object being inspected from more angles. For areas with uneven surfaces (such as uneven metal pads caused by the tin plating process on PCB circuit boards), the larger light-emitting surface, through its uniform and large-area illumination distribution, can ensure that the reflected light from the uneven areas is uniformly received by the camera module 201, avoiding local dark areas caused by uneven surfaces and preventing normal unevenness of the tin-plated board from being misjudged as defects.

[0096] In practical applications, the second light source module 40 can be used in conjunction with the first light source module 20 to form a comprehensive light source system. By adjusting the brightness and off state of the first light source unit 21, the second light source unit 22, and the second light source module 40, high-resolution and recognizable images of the metal pads and solder resist layer of the PCB circuit board can be acquired, satisfying the defect detection needs of partially blackened solder plating boards (white ink), partially blackened OSP boards, and partially uneven solder plating boards.

[0097] In some embodiments, the second light source module 40 further includes a dimming element 43 (see Figure 4 The dimming element 43 is disposed between the second substrate 41 and the anti-transmitting module 50. The dimming element 43 is used to scatter the light emitted by the second light source module 40 to the anti-transmitting module 50. The dimming element 43 can increase the projection range and uniformity of the light emitted by the second light source module 40.

[0098] The dimming element 43 can be one of a light-diffusing plate, a light-concentrating lens, a light guide plate, or a modulation film. For example, when the dimming element 43 is a light-diffusing plate, it can achieve light with a soft angle. When the dimming element 43 is a light-concentrating lens, a light guide plate, or a modulation film, it can achieve parallel light or focused light with a converged angle, thus meeting the detection needs in different scenarios.

[0099] In some embodiments, the second light source module 40 further includes a second heat sink 44, which is disposed on the side of the second substrate 41 away from the second light emitter 42. The second heat sink 44 may be a metal plate with good thermal conductivity. For example, the second heat sink 44 may be configured as a serrated aluminum plate to improve thermal conductivity.

[0100] Optionally, the second light source module 40 further includes a second cooling fan 45, which is disposed on the side of the second heat sink 44 away from the second substrate 41. There may be multiple second cooling fans 45, which are spaced apart along the length of the second heat sink 44 to improve heat dissipation efficiency.

[0101] In some embodiments, the housing 10 includes two oppositely arranged cover plates 15, and the reflective module 50 includes two oppositely arranged mounting plates 51 and a reflective sheet 52. The two ends of the mounting plates 51 are respectively fixedly connected to the corresponding cover plates 15. The mounting plates 51 are provided with a groove 510 along their length direction. The reflective sheet 52 is disposed between the two mounting plates 51 and installed in the groove 510.

[0102] Optionally, the reflective sheet 52 can be a glass sheet with a certain light reflection and light transmission capability. The light emitted by the second light source 42 can be refracted by the reflective sheet 52 and directed vertically toward the object to be tested. At the same time, the light reflected back from the object to be tested can pass through the reflective module 50 and be directed toward the camera module 201.

[0103] Two mounting plates 51 are positioned between two cover plates 15. The two ends of the mounting plates 51 are fixedly connected to the cover plates 15 by screws, snap-fits, or other methods. A reflective sheet 52 is positioned between the two mounting plates 51. Each mounting plate 51 has a groove 510 on the side facing the reflective sheet 52. After assembly, the reflective sheet 52 is inserted into the groove 510, with both ends of the reflective sheet 52 abutting against the end faces, ensuring the stability of the reflective sheet 52 assembly. When it is necessary to disassemble the reflective sheet 52, only one cover plate 15 needs to be removed, and then the reflective sheet 52 can be taken out from the groove 510 without disassembling the mounting plates 51, making the process convenient and quick.

[0104] In some embodiments, the cover plate 15 is a reflector with high reflectivity, which enables the cover plate 15 to effectively reflect light and reduce light signal loss, thereby compensating for the insufficient illumination in the edge area of ​​the first light source module and the second light source module, and ensuring more uniform light distribution.

[0105] In some embodiments, the inner sidewall of the cover plate 15 is provided with a reflective element (not shown). The reflective element can be high-reflectivity aluminum (reflectivity of 95% or more) or high-reflectivity sticker, etc. The reflective element can effectively reflect light, thereby compensating for the insufficient lighting problem in the edge area of ​​the first light source module 20 and the second light source module 40, and ensuring a more uniform light distribution.

[0106] Please see Figure 3 In some embodiments, the light box 100 further includes a first light-absorbing element 60 and a second light-absorbing element 70. The first light-absorbing element 60 is disposed on the inner side wall of the box body 10 and is located on the side of the reflective module 50 away from the second light source module 40. The second light-absorbing element 70 is disposed on the inner top wall of the box body 10.

[0107] The first light-absorbing element 60 and the second light-absorbing element 70 can be made of materials with good light-absorbing properties. For example, the first light-absorbing element 60 and the second light-absorbing element 70 can be black light-absorbing velvet, which can effectively absorb light and reduce interference caused by light reflection. Optionally, the first light-absorbing element 60 is installed on the inner side wall of the housing 10 by adhesive bonding, that is, the first light-absorbing element 60 is installed on the inner surface of a side plate 14 that is far away from the second light source module 40, and the second light-absorbing element 70 is installed on the inner top wall of the housing 10 by adhesive bonding, that is, the second light-absorbing element 70 is installed on the inner surface of the top plate 12.

[0108] The first light-absorbing element 60 and the second light-absorbing element 70 are used to absorb the energy of the light transmitted from the light-transmitting sheet and significantly reduce the intensity of stray light. This effectively prevents the light reflected back from the inner side wall and inner top wall of the housing 10 from interfering with the imaging of the camera module 201 and ensures the imaging quality.

[0109] In some embodiments, such as Figure 5 As shown, the cover plate 15 is provided with multiple interfaces 150 that can be adapted to different types of power supply devices such as constant current sources or time-sequential strobe controllers. Through the corresponding interfaces 150, the first light source unit 21, the second light source unit 22, or the first light source module 20 can be connected and cooperated with different types of power supply devices. When the first light source unit 21, the second light source unit 22, and the first light source module 20 are connected to the constant current source through the corresponding interfaces 150, the first light source unit 21, the second light source unit 22, and the first light source module 20 remain in a constantly lit state.

[0110] The time-sequence strobe controller can control the on / off state and brightness of the corresponding light source. When the first light source unit 21, the second light source unit 22, and the first light source module 20 are connected to the time-sequence strobe controller through the corresponding interface 150, the on / off state and brightness of the first light source unit 21, the second light source unit 22, and the first light source module 20 can be adjusted according to the different timing signals sent by the time-sequence strobe controller. In this way, the lighting mode can be diversified, and the camera module 201 can capture multiple independent images with no interference between the light sources.

[0111] Based on the same utility model concept, such as Figure 1 As shown, this utility model embodiment also provides a detection device 200, which includes a light box 100 as in any of the above embodiments and a camera module 201. The camera module 201 is disposed at the acquisition port 110 and is used to acquire image information of the object to be detected.

[0112] The detection device 200 can be used to detect defects in the object to be tested (such as a PCB circuit board). Since the detection device 200 includes the light box 100 as in any of the above embodiments, it also has the beneficial effects of any of the above embodiments. The specific beneficial effects have been described in detail above and will not be repeated here.

[0113] Optionally, the inspection device 200 also includes a transmission module 202, which can transport the object to be inspected to the inspection station (i.e., the position below the light box 100) so that the appearance defects of the object to be inspected can be detected using the light box 100 and the camera module 201.

[0114] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it; under the concept of this utility model, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of this utility model as described above. For the sake of brevity, they are not provided in detail; although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some 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 this utility model.

Claims

1. A light box (100), characterized in that, The utility model relates to a kind of light detection device, including: Box (10), the light path passage (11) is provided with in first direction of the box (10), the opposite ends of the light path passage (11) form acquisition port (110) and light outlet (111) respectively; First light source module (20), the first light source module (20) is set in the box (10); Arc light modulation module (30), the arc light modulation module (30) is set at the light outlet (111), the middle part of the arc light modulation module (30) is relative to the two ends of the arc light modulation module (30) and is arched along the direction of the light outlet (111) and points to the acquisition port (110), light emitted from the first light source module (20) can be shot to the arc light modulation module (30), and after being diffusely reflected by the arc light modulation module (30), it is shot to the object to be detected.

2. The light box (100) according to claim 1, characterized in that The arc light modulation module (30) includes two arc light modulation plates (31) symmetrically arranged, and an opening (310) is formed between the two arc light modulation plates (31), and the opening (310) is arranged opposite to the light outlet (111) and the acquisition port (110) respectively.

3. The light box (100) according to claim 2, characterized in that The first light source module (20) includes two first light source units (21) and two second light source units (22), the two first light source units (21) are arranged on the opposite sides of the arc light modulation module (30) in the second direction respectively, and the two second light source units (22) are arranged on the opposite sides of the arc light modulation module (30) in the second direction respectively, and the light emitting surface of the first light source unit (21) and the light emitting surface of the second light source are both directed to the arc light modulation module (30).

4. The light box (100) according to claim 3, characterized in that The second light source unit (22) is arranged on the side of the first light source unit (21) close to the acquisition port (110), the included angle between the light angle provided by the first light source unit (21) and the horizontal direction is between 0° and 30°, and the included angle between the light angle provided by the second light source unit (22) and the horizontal direction is between 45° and 70°.

5. The light box (100) according to claim 3, characterized in that The first light source unit (21) and the second light source unit (22) both include a first light emitter (211), and the first light emitter (211) is a white light LED lamp bead or an infrared LED lamp bead.

6. The light box (100) according to claim 2, characterized in that The box (10) includes a top plate (12) and a bottom plate (13) arranged oppositely, the acquisition port (110) is formed in the top plate (12), the bottom plate (13) has two parts, the two bottom plates (13) are arranged at intervals and form the light outlet (111), and the two arc light modulation plates (31) are arranged on the corresponding bottom plates (13) respectively; The bottom plate (13) is a reflective plate.

7. The light box (100) according to claim 2, characterized in that The light box (100) further comprises a second light source module (40) and a reflection module (50), the second light source module (40) is located on the side of the first light source module (20) close to the collection port (110), and the reflection module (50) is arranged obliquely at the light path channel (11), so that the light emitted from the second light source module (40) can be reflected by the reflection module (50) and then be emitted to the light outlet (111).

8. The light box (100) according to claim 7, characterized in that The second light source module (40) comprises a second substrate (41) and a second light emitter (42) arranged in an array on one side of the second substrate (41), and the width of the second substrate (41) is twice or more than the width of the opening (310).

9. The light box (100) according to claim 8, characterized in that The light box (100) further comprises a light adjusting piece (43), the light adjusting piece (43) is arranged between the second substrate (41) and the reflection module (50), and the light adjusting piece (43) is any one of a light homogenizing plate, a condenser lens, a light guide plate or a modulation film.

10. The light box (100) according to claim 7, characterized in that The box body (10) comprises two oppositely arranged cover plates (15), and the cover plates (15) are reflective plates. The reflection module (50) comprises two oppositely arranged mounting plates (51) and a reflection sheet (52), the two ends of the mounting plate (51) are fixedly connected with the corresponding cover plate (15), and the mounting plate (51) is provided with a sliding groove (510) along the length direction of the mounting plate (51), and the reflection sheet (52) is arranged between the two mounting plates (51) and is mounted in the sliding groove (510).

11. The light box (100) according to claim 7, characterized in that The light box (100) further comprises a first light absorbing piece (60) and a second light absorbing piece (70). The first light absorbing piece (60) is arranged on the inner side wall of the box body (10), and the first light absorbing piece (60) is located on the side of the reflection module (50) away from the second light source module (40), and the second light absorbing piece (70) is arranged on the inner top wall of the box body (10).

12. A detection device (200), characterized in that The light box (100) comprises the light box (100) according to any one of claims 1-11; and A camera module (201) is arranged at the collection port (110) and used for collecting image information of the object to be detected. The light box (100) comprises the light box (100) according to any one of claims 1-11; and A camera module (201) is arranged at the collection port (110) and used for collecting image information of the object to be detected.

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