Light source assembly for thin film surface defect detection

Abstract

The utility model discloses a light source assembly for film surface defect detection, which comprises a light source box and a line light source arranged in the light source box, the light source box is provided with a light-transmitting window corresponding to the line light source, and the light-transmitting window is provided with a light-transmitting plate, a shading blade and a pressing limiting plate. The number of the pressing and limiting plates is two, the light-transmitting plate and the shading blade are pressed and limited to the light-transmitting window from the two sides, the back of the shading blade is pressed by one pressing and limiting plate, and the cutting edge of the shading blade and the other pressing and limiting plate are spaced to form a light seam for light rays of the line light source to penetrate through. The device has the advantages that light rays emitted by the linear light source penetrate through the light-transmitting plate and then are emitted through the light seam between the shading blade and the pressing limiting plate on the blade side, the light rays are diffracted in the blade cutting edge area of the shading blade and irradiate the surface of the to-be-detected film to form light and dark stripes, and defects on the surface of the to-be-detected film can be presented more stereoscopically; and the detection effect is improved.

Description

Technical Field

[0001] This utility model relates to the field of membrane material defect detection, specifically to a light source assembly for detecting surface defects in thin films. Background Technology

[0002] In machine vision inspection systems, the selection and use of light sources are crucial for accurate defect detection. When inspecting defects on the surfaces of thin films such as optical films or food films, ordinary line light sources suffer from limitations due to their single beam pattern. This not only limits the illumination range but also makes it difficult to visualize the three-dimensionality of surface irregularities and small defects, hindering the camera's ability to detect defect locations. While cross-line light sources or shadowless light sources can address some of these issues, their relatively high cost necessitates appropriate modifications to ordinary line light sources to enable their effective application in detecting defects on thin film surfaces. Utility Model Content

[0003] This invention provides a light source assembly for detecting defects on thin film surfaces, aiming to overcome the aforementioned shortcomings in the prior art.

[0004] The technical solution of this utility model to solve the above-mentioned technical problems is as follows: A light source assembly for detecting defects on thin film surfaces includes a light source box and a line light source disposed in the light source box. The light source box is provided with a light-transmitting window corresponding to the line light source. A light-transmitting plate, a light-shielding blade, and a pressing and limiting plate are provided at the light-transmitting window. There are two pressing and limiting plates, which press and limit the light-transmitting plate and the light-shielding blade from both sides to the light-transmitting window. The back of the light-shielding blade is pressed by one of the pressing and limiting plates, and the blade edge of the light-shielding blade is spaced apart from the other pressing and limiting plate to form a light slit through which the light from the line light source can pass.

[0005] Based on the above technical solution, the present invention can be further improved as follows.

[0006] Furthermore, the light source box includes a front side plate and a rear side plate, both of which are L-shaped. The front side plate and the rear side plate are fixedly connected by a left side plate and a right side plate located at the left and right ends. The left and right ends of the linear light source are fixedly connected to the left side plate and the right side plate respectively. The front side plate and the rear side plate are both composed of vertical plates and horizontal plates. The two horizontal plates of the front side plate and the rear side plate are arranged opposite to each other, and the light-transmitting window extending to the left and right is provided in the middle interval area at the junction.

[0007] Furthermore, the light-transmitting plate covers the two horizontal plates and closes the light-transmitting window.

[0008] Furthermore, the light-transmitting plate is an acrylic plate.

[0009] Furthermore, the acrylic sheet is composed of two layers of rectangular sheets of the same specifications stacked together, with each layer of rectangular sheets having a thickness of 1.5-2mm.

[0010] Furthermore, the clamping limiting plate has a clamping groove at its bottom near the light-transmitting window for clamping the light-transmitting plate and / or the light-shielding blade. The other side of the clamping limiting plate is fixedly connected to the horizontal plate by screws. The clamping limiting plate and the horizontal plate are provided with a plurality of screw holes for the screws to be inserted, corresponding one-to-one.

[0011] Furthermore, the vertical plate is provided with an array of oval holes for heat dissipation.

[0012] Furthermore, the light-transmitting plate is located below the light-shielding blade, and the pressing and limiting plate is located above the back of the light-shielding blade.

[0013] Furthermore, the width of the light-transmitting window is 5-10mm, the width of the light slit is 1-5mm, and the width of the light-transmitting plate is 15-20mm.

[0014] Furthermore, the width of the light-shielding blade is 8-10mm, the thickness is 0.15-0.25mm, and the thickness at the blade edge is 0.08-0.12mm.

[0015] Compared with the prior art, the beneficial effects of this utility model are:

[0016] This invention improves the structure of a conventional line light source by incorporating a clamping and limiting plate, a light-shielding blade, and a light-transmitting plate at the light-transmitting window. The light emitted by the line light source passes through the light-transmitting plate and then exits through the light slit between the light-shielding blade and the clamping and limiting plate on the blade side. The light diffracts at the cutting edge of the light-shielding blade, illuminating the surface of the film to be inspected and forming alternating bright and dark stripes. This allows the defects on the surface of the film to be inspected to be presented in a more three-dimensional manner, thereby improving the inspection effect. Attached Figure Description

[0017] Figure 1 An isometric view of a light source assembly for detecting thin film surface defects provided by this utility model;

[0018] Figure 2 for Figure 1 The front view of the light source component shown;

[0019] Figure 3 for Figure 1 An exploded view of the light source assembly shown.

[0020] Figure 4 for Figure 1 A cross-sectional view of the light source assembly shown;

[0021] Figure 5A photograph taken by a camera when using the light source assembly provided by this utility model for thin film inspection (with alternating bright and dark stripes and more three-dimensional defect display).

[0022] The attached diagram lists the components represented by each number as follows:

[0023] 1. Light source box; 2. Linear light source; 3. Light-transmitting window; 4. Light-transmitting plate; 5. Light-shielding blade; 6. Pressing and limiting plate; 7. Front side plate; 8. Rear side plate; 9. Left side plate; 10. Right side plate; 11. Screw hole; 12. Oval hole. Detailed Implementation

[0024] The technical solution provided by this utility model will be clearly and completely described below with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0025] In the description of this utility model, if terms such as "upper", "lower", "left", "right", "top", "bottom", "inner", and "outer" are used to indicate the orientation or positional relationship, the orientation or positional relationship indicated is based on the orientation or positional relationship shown in the accompanying drawings. They 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. Therefore, they should not be construed as limitations on this utility model.

[0026] like Figures 1 to 4 As shown, this utility model provides a light source assembly for detecting defects on thin film surfaces, which includes a light source box 1 and a line light source 2 disposed in the light source box 1. The light source box 1 is provided with a light-transmitting window 3 corresponding to the line light source 2. A light-transmitting plate 4, a light-shielding blade 5 and a pressing and limiting plate 6 are provided at the light-transmitting window 3. There are two pressing and limiting plates 6, which press and limit the light-transmitting plate 4 and the light-shielding blade 5 from both sides and limit them to the light-transmitting window 3. The back of the light-shielding blade 5 is pressed by one of the pressing and limiting plates 6, and the blade of the light-shielding blade 5 is spaced apart from the other pressing and limiting plate 6 to form a light slit through which the light from the line light source 2 can pass.

[0027] It should be noted that during the testing of thin film products, the best imaging effect can be achieved by aligning the industrial camera with the blade edge (i.e., the blade) above the light source. In this invention, the line light source is fixed inside the light source box, and the light emitted from it is emitted through the light-transmitting window. During the process, the light will first penetrate the light-transmitting plate, part of which is blocked by the light-shielding blade, and part of which is diffracted at the blade edge. Finally, the light emitted from the light slit will form alternating light and dark stripes on the surface of the film to be tested.

[0028] In one embodiment of this utility model, the light source box 1 includes a front side plate 7 and a rear side plate 8, both L-shaped. The front side plate 7 and the rear side plate 8 are fixedly connected by a left side plate 9 and a right side plate 10 located at the left and right ends, respectively. The left and right ends of the linear light source 2 are correspondingly fixedly connected to the left side plate 9 and the right side plate 10. The front side plate 7 and the rear side plate 8 are both composed of vertical and horizontal plates. The two horizontal plates of the front side plate 7 and the rear side plate 8 are arranged opposite each other, and a light-transmitting window 3 extending to the left and right is provided in the middle interval area at the junction. The light-transmitting plate 4 covers the two horizontal plates and closes the light-transmitting window 3. The light-transmitting plate 4 is an acrylic plate, which is composed of two layers of rectangular plates of the same specifications stacked on top of each other, and the thickness of each layer of rectangular plates is 1.5-2mm.

[0029] It should be noted that the length of the acrylic sheet is the same as or slightly longer than the length of the linear light source, and the width is preferably 20mm.

[0030] In one embodiment of the present invention, the pressing and limiting plate 6 is provided with a pressing groove at the bottom of the side near the light-transmitting window 3 for pressing the light-transmitting plate 4 and / or the light-blocking blade 5. The other side of the pressing and limiting plate 6 is fixedly connected to the horizontal plate by screws. The pressing and limiting plate 6 and the horizontal plate are provided with a plurality of screw holes 11 for the screws to be inserted.

[0031] It should be noted that there are two clamping limit plates, each preferably 20mm wide and 8mm high (thickness). A portion of the side is milled off to form a clamping groove 5mm wide and 3mm high, which is used to clamp the acrylic plate and the blade. The screw hole is preferably a countersunk hole.

[0032] In one embodiment of the present invention, the vertical plate is provided with an array of oval holes 12 for heat dissipation.

[0033] In one embodiment of this utility model, the light-transmitting plate 4 is located below the light-shielding blade 5, and the pressing and limiting plate 6 is located above the back of the light-shielding blade 5.

[0034] In one embodiment of this utility model, the width of the light-transmitting window 3 is 5-10mm, the width of the light slit is 1-5mm, and the width of the light-transmitting plate 4 is 15-20mm.

[0035] In one embodiment of this utility model, the width of the light-shielding blade 5 is 8-10mm, the thickness is 0.15-0.25mm, the thickness at the blade edge is 0.08-0.12mm, and the width at the blade edge is preferably 1-2mm.

[0036] During installation, place the light-shielding blade, acrylic plate, and limiting clamping plate in that order. Use the clamping groove on the side of the limiting clamping plate to clamp the light-shielding blade to the acrylic plate, ensuring that the blade edge is located in the light-transmitting window area. This ensures the stable fixation of the blade and also causes light diffraction, meeting the needs of efficient and accurate detection.

[0037] Using the light source assembly for thin film surface defect detection provided in the above embodiments of this utility model, the thin film is subjected to defect detection, and the resulting photographs are as follows: Figure 5 As shown, the light source assembly forms alternating bright and dark stripes on the surface of the film under test, and defects such as pinholes, dents, and black spots can be displayed more three-dimensionally and clearly, with good results.

[0038] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A light source assembly for detecting surface defects in thin films, characterized in that, The utility model provides a light source box and line light source in the light source box, the light source box is equipped with light transmission window corresponding with the line light source, the light transmission window is equipped with light transmission plate, light shielding blade and compression limiting plate, the compression limiting plate is two and from two sides compresses tightly and limits the light transmission plate and light shielding blade at the light transmission window, the back of the light shielding blade is compressed tightly by one compression limiting plate, the cutting edge of the light shielding blade is spaced apart from the other compression limiting plate to form the light gap for the light of the line light source to transmit.

2. The light source assembly for film surface defect inspection according to claim 1, wherein The light source box includes front side plate and rear side plate which are both L-shaped, the front side plate and the rear side plate are fixedly connected through left side plate and right side plate located at left and right ends, the left and right ends of the line light source are fixedly connected with the left side plate and the right side plate, the front side plate and the rear side plate are both composed of vertical plate and horizontal plate, the two horizontal plates of the front side plate and the rear side plate are arranged opposite to each other and the light transmission window extending left and right is arranged at the middle interval area of the intersection.

3. The light source assembly for thin film surface defect inspection according to claim 2, wherein The light transmission plate covers the top of the two horizontal plates and closes the light transmission window.

4. The light source assembly for thin film surface defect inspection according to claim 2, wherein The light transmission plate is acrylic plate.

5. The light source assembly for thin film surface defect inspection according to claim 4, wherein The acrylic plate is composed of two layers of rectangular plates of the same specification, and the thickness of each layer of the rectangular plate is 1.5-2mm.

6. The light source assembly for film surface defect inspection according to claim 2, wherein The compression limiting plate is equipped with compression groove for compressing the light transmission plate and / or light shielding blade at the bottom of the side close to the light transmission window, the other side of the compression limiting plate is fixedly connected with the horizontal plate through screw, and the compression limiting plate and the horizontal plate are one-to-one corresponding and equipped with a plurality of screw holes for the screw.

7. The light source assembly for thin film surface defect inspection according to claim 2, wherein The vertical plate is arrayed with waist round holes for heat dissipation.

8. The light source assembly for thin film surface defect inspection according to claim 1, wherein The light shielding blade is below the light transmission plate, and the back of the light shielding blade is above the compression limiting plate.

9. The light source assembly for thin film surface defect inspection according to any one of claims 1 to 8, wherein The width of the light transmission window is 5-10mm, the width of the light gap is 1-5mm, and the width of the light transmission plate is 15-20mm.

10. The light source assembly for thin film surface defect inspection according to claim 9, wherein The width of the light shielding blade is 8-10mm, the thickness is 0.15-0.25mm, and the thickness at the cutting edge is 0.08-0.12mm.

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