Lead tab inspection device

Abstract

A lead tab inspection device according to an embodiment comprises: a light source which generates light; a collimator which collimates the light generated from the light source, into parallel light; an objective lens on which the light passing through a lead tab is incident; an image detector which detects the light passing through the objective lens; and a controller which controls the light source, wherein the controller controls the light source such that the light source emits light of different light intensities.

Description

Lead tab inspection device

[0001] The present invention relates to a device for inspecting lead tabs used in secondary batteries.

[0002] Lithium secondary batteries are manufactured in various forms, such as cylindrical, prismatic, and pouch types. Pouch-type lithium secondary batteries have a structure in which a battery plate is sealed inside an aluminum pouch filled with electrolyte, and lead metal attached to the battery plate protrudes to the outside of the pouch. The lead metal is made of thin, elongated metal plates such as aluminum or nickel-plated copper, and the aluminum pouch is a composite film in which a synthetic resin-based film is covered on both sides of an aluminum foil. When sealing a battery plate filled with electrolyte using an aluminum pouch, the bonding between the lead metal and the pouch film is poor, which can lead to leakage of the electrolyte through the boundary between the lead metal and the pouch.

[0003] To prevent this, lead tabs are used in which a lead film that adheres well to both the lead metal and the pouch film is pre-fused to the lead metal. Lead tabs are a key component that determines stable power supply and battery life in pouch-type batteries. Small gaps or bubbles formed at the bonding site between the lead film and the lead metal, or bubbles remaining inside the lead film, can cause electrolyte leakage during the use of the secondary battery and, furthermore, lead to a fire.

[0004] Therefore, in order to increase the productivity and manufacturing reliability of secondary batteries, it is necessary to inspect bubbles and other defects formed inside the lead tabs in advance to quickly and accurately detect and classify defective lead tabs. Additionally, it is necessary to obtain clear images of defects such as bubbles to analyze the cause of their occurrence.

[0005] Conventionally, visual or vision inspection methods have been used for inspecting lead tabs, but visual or vision inspections have difficulty detecting defects such as bubbles that occur inside the lead film or at the boundary between the lead film and the lead metal edge.

[0006] Meanwhile, although the presence of bubbles inside the lead tab can be inspected using a transmission microscope, it is difficult to detect them with light-based vision inspection due to increased impermeability caused by internal scattering and absorption resulting from the multipolymer structure of the lead film and additive materials such as carbon black. In addition, microscopes generally have a shallow depth of field, making them unsuitable for inspecting relatively thick lead tabs.

[0007] In addition, Optical Coherence Tomography (OCT) is used as a method to precisely inspect lead tabs. OCT provides depth-specific tomographic images and can provide three-dimensional images by synthesizing these tomographic images. However, OCT cannot provide clear images due to severe image noise. Furthermore, it requires processing an excessive amount of data to create three-dimensional images, and continuous image processing is complex and expensive.

[0008] Meanwhile, during the process of heat-fusing the lead film to the lead metal, variations in light transmittance may occur depending on the location due to differences in thermal conductivity characteristics near the metal edge. Consequently, in vision inspection based on a single light source and single illuminance, the contrast of internal defects in the lead film is not stably formed, making precise detection difficult.

[0009] The problem that the present invention aims to solve is to provide a lead tab inspection device capable of precisely detecting defects within a lead film having regions of different transmittances.

[0010] Another problem that the present invention aims to solve is to provide a new lead tab inspection device capable of rapidly and accurately inspecting defects, such as bubbles formed within the lead film and between the lead film and the lead metal.

[0011] Another problem that the present invention aims to solve is to provide a new lead tab inspection device capable of providing a clear image of defects, such as bubbles, occurring at the boundary between the lead film and the lead metal edge.

[0012] According to one embodiment of the present invention, a lead tab inspection device is provided. The lead tab inspection device comprises a light source that generates light, a collimator that collimates the light generated from the light source into parallel light, an objective lens into which light transmitted through the lead tab is incident, an image detector that detects the light passing through the objective lens, and a controller that controls the light source, wherein the controller controls the light source so that the light source emits light of different light intensities.

[0013] In one embodiment, the objective lens may be composed of a telecentric lens.

[0014] In one embodiment, light of different light intensities may be emitted for different periods of time.

[0015] In one embodiment, the light source may emit light of at least two different wavelengths. Furthermore, the light of different light intensities may be emitted for the same amount of time.

[0016] The above controller can control the divergence angle of the above collimator.

[0017] The above objective lens may have an aperture angle less than or equal to the divergence angle of the above collimator.

[0018] In one embodiment, the objective lens may have an aperture angle of less than 10 degrees, and furthermore, may have an aperture angle of less than 1 degree.

[0019] In one embodiment, the lead tab inspection device may further include a beam splitter, and the image detector may include a first image detector and a second image detector that each detect light separated from the beam splitter.

[0020] Furthermore, the lead tab inspection device may further include an image processor that aligns images obtained from the first image detector and the second image detector.

[0021] The beam splitter can separate the wavelength or light intensity of light emitted from the light source.

[0022] In one embodiment, the lead tab inspection device may further include an image processor that processes an image obtained through the image detector, and an image analyzer that analyzes the image processed by the image processor.

[0023] The image detector can detect a first image based on a first light intensity and a second image based on a second light intensity, and the image processor can align the first image and the second image.

[0024] The above image analyzer can automatically detect defects present in the lead tab by analyzing the image processed by the above image processor.

[0025] According to embodiments of the present invention, a lead tab inspection device capable of precisely detecting defects within a lead film having regions of different transmittances can be provided.

[0026] In addition, according to embodiments of the present invention, a lead tab inspection device can be provided that can rapidly and accurately inspect defects such as bubbles in a relatively thick lead film and gaps formed in the boundary region between the lead film and the lead metal by irradiating a collimated light to the inspection target area of ​​the lead tab and acquiring an image using an objective lens having a narrow aperture angle.

[0027] Furthermore, according to embodiments of the present invention, a lead tab inspection device capable of precisely detecting defects can be provided by providing a clear image of defects such as the interface between the lead film and the lead metal or bubbles.

[0028] Figure 1 is a schematic plan view illustrating a typical pouch-type lithium secondary battery.

[0029] FIG. 2a is a schematic plan view illustrating a typical lead tab.

[0030] FIG. 2b is a schematic cross-sectional view taken along the cut line AA of FIG. 2.

[0031] FIG. 3 is a schematic cross-sectional view illustrating a lead tab inspection device according to one embodiment of the present invention.

[0032] FIG. 4 is a schematic cross-sectional view illustrating light detection according to one embodiment of the present invention.

[0033] Figure 5 is a schematic graph illustrating the light transmittance according to the inspection area of ​​the littab.

[0034] FIG. 6 is a schematic graph illustrating a ret-tab inspection method according to one embodiment of the present invention.

[0035] FIG. 7a is a schematic diagram illustrating an image of a lead tab obtained by irradiating light with a first light intensity according to one embodiment of the present invention.

[0036] FIG. 7b is a schematic diagram illustrating an image of a lead tab obtained by irradiating light with a second light intensity according to one embodiment of the present invention.

[0037] Figure 7c is a schematic diagram for explaining the image of a retab obtained by aligning the image information of Figures 7a and 7b.

[0038] FIG. 8 is a schematic graph for explaining a retab inspection method according to another embodiment of the present invention.

[0039] FIG. 9 is a schematic cross-sectional view illustrating a ret tab inspection device according to another embodiment of the present invention.

[0040] Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings. The embodiments described below are provided as examples to ensure that the concept of the present invention is sufficiently conveyed to those skilled in the art to which the present invention pertains. Accordingly, the present invention is not limited to the embodiments described below and may be embodied in other forms. Throughout the specification, the same reference numerals indicate the same components.

[0041] FIG. 1 is a schematic plan view illustrating a typical pouch-type lithium secondary battery, FIG. 2a is a schematic plan view illustrating a typical lead tab, and FIG. 2b is a schematic cross-sectional view taken along cut line AA of FIG. 2.

[0042] Referring to FIGS. 1, 2a, and 2b, a pouch-type lithium secondary battery (10) includes a pouch film (11) and positive and negative lead tabs (20). The pouch film (11) seals the main materials inside the secondary battery, such as the battery plates of the positive and negative electrodes separated by a separator and the electrolyte.

[0043] The lead tab (20) is connected to a battery plate sealed by a pouch film (11) and exposed to the outside. The lead tab (20) may be placed together on one side of the secondary battery (10) as shown in FIG. 1, or may be placed opposite each other.

[0044] The lead tab (20) includes a lead metal (13) connected to the battery plate and a lead film (15) that partially surrounds the lead metal (13). The lead film (15) is fused to the lead metal (13) and also adheres to the pouch film (11) when sealing the battery plate, etc. with the pouch film (11) to prevent leakage of the electrolyte.

[0045] As illustrated in FIGS. 2a and 2b, the lead tab (20) includes a lead film (15) that partially wraps a lead metal (13) in the shape of a metal plate. The lead metal (13) is generally formed of aluminum for the anode and nickel-plated copper for the cathode. The lead film (15) may include an upper lead film (15a) and a lower lead film (15b), and the upper lead film (15a) and the lower lead film (15b) are fused at the upper and lower ends of the lead metal (13). The upper lead film (15a) and the lower lead film (15b) are attached to each other at an interface (15ab).

[0046] The upper and lower lead films (15a, 15b) may each be formed as a single layer, but generally have a functional multilayer structure. The lead film (15) is formed of a polyolefin composite polymer resin that has excellent adhesion to lead metal and pouch film, good insulation properties, and sealing effect, and may include additives to improve properties as needed, and generally has opaque properties.

[0047] Lead tabs (20) are manufactured by fusing lead films (15) at regular intervals to lead metal (13) straps having a certain width, and are supplied by winding them onto a reel. When manufacturing a pouch-type battery, the lead metal straps are cut into individual lead tabs (20) suitable for the battery.

[0048] The lead film (15) is intended to help fuse the pouch film (11) and the lead metal (13). However, if the lead film (15) is incompletely fused to the lead metal (13), a gap (cavity) may be formed at the interface between the lead metal (13) and the lead film (15), or bubbles may remain inside the lead film (15). The gap or bubbles increase in size due to heat generated from using the secondary battery, and consequently, cause electrolyte leakage and fire. Therefore, it is necessary to inspect the lead tabs and remove defective lead tabs before welding the lead tabs to the battery plate, and it is also necessary to inspect the lead tabs after manufacturing the battery and classify batteries with defective lead tabs attached as defective.

[0049] FIG. 3 is a schematic cross-sectional view illustrating a lead tab inspection device according to one embodiment of the present invention.

[0050] Referring to FIG. 3, a lead tab inspection device (100) according to one embodiment of the present invention may include a light source (21), a collimator (23), an objective lens (29), an image detector (31), an image processor (33), an image analyzer (35), and a controller (37).

[0051] The light source (21) generates light for inspecting the lead tab (20). The light emitted from the light source (21) may be, for example, visible light or near-infrared light. The wavelength band of the light emitted from the light source (21) may be selected according to the transmission characteristics of the lead film (15). For example, if the lead film (15) transmits visible light better than near-infrared light, a white light-emitting diode may be used as the light source (21), and conversely, if it transmits near-infrared light better, a near-infrared light-emitting diode may be used as the light source (21).

[0052] A light source (21) comprising a single light-emitting diode may be used, but the present invention is not limited thereto. A surface light source in which a plurality of light-emitting diodes are arranged may also be used as the light source (21). The light emitted from individual light-emitting diodes may emit light that has a Lambethian distribution and may emit light that has a smaller directional angle. Additionally, an illumination optical system may be included to generate light with a uniform light distribution on the plane of the lead tab being inspected.

[0053] In one embodiment, the light source (21) may emit light of different light intensities. For example, it may emit light of a first intensity and then emit light of a second intensity.

[0054] In one embodiment, the light source (21) can emit light of different wavelengths simultaneously or at different times.

[0055] The collimator (23) collimates the light emitted from the light source (21). The collimator (23) can diverge the light irradiated onto the lead tab (20) by an angle (θ) in a vertical direction. By adopting the collimator (23), the light can be irradiated onto the lead tab (20) in the same direction.

[0056] The objective lens (29) transmits light that has passed through the lead film (15). Generally, in the case of an objective lens with a large field of view, the size of the subject image varies depending on the distance between the objective lens and the subject, causing a perspective error that reduces measurement accuracy. To prevent this, in embodiments of the present invention, the objective lens (29) has a relatively small aperture angle (29a). In one embodiment, the aperture angle (29a) of the objective lens (29) may be smaller than the divergence angle of the light passing through the collimator (23). For example, the aperture angle (29a) may be smaller than 30 degrees, further smaller than 10 degrees, further smaller than 1 degree, further smaller than 0.1 degrees.

[0057] The objective lens (29) is configured to detect light generally parallel to the optical axis, so that objects and defects can be detected regardless of the distance from the subject, i.e., the working distance. Therefore, since there is no change in the size of objects and defects even if the working distance is different, the dimensions of objects or defects, the distance between two points, etc., can be accurately measured. For example, the objective lens (29) can be configured as a telecentric lens.

[0058] By adopting an objective lens (29) having a small aperture angle, such as a telecentric lens, diffuse reflection occurs at the lead tab (20), preventing the outline of defects such as bubbles or the edge contours of the lead metal (13) from becoming blurred, thereby enabling the acquisition of a clear, high-contrast image. Furthermore, since the objective lens (29) has a small aperture angle, the depth of field can be increased, allowing for the acquisition of a clear image of defects such as bubbles distributed at various depths of the relatively thick lead film (15), and the measurement accuracy can be improved due to minimal perspective distortion.

[0059] In this embodiment, a collimator (23) is used to irradiate the lead tab (20) with collimated light, and an objective lens (29) having a small aperture angle (29a) is used to detect light emitted at an angle within the aperture angle (29a) among the light passing through the lead tab (20). Accordingly, a clear image of defects such as bubbles within the lead tab (20) can be obtained. The light detection effect according to the embodiment of the present invention will be explained with reference to FIG. 4.

[0060] Referring to FIG. 4, incident light collimated by the collimator (23) is irradiated onto the lead tab (20), and light passing through the lead tab (20) is incident on the objective lens (29).

[0061] When a bubble (D) occurs within the lead film (15), the path of light passing through the lead film (15) and the bubble (D), which have different refractive indices, follows Snell's law. If the angle of incidence to the bubble (D) is smaller than the critical angle, the light is refracted and passes through the bubble and continues to proceed; if the angle of incidence is larger than the critical angle, the light undergoes total internal reflection at the boundary of the bubble (D). Because the density of the lead film (15) is higher than that of air, the bubble (D) within the lead film (15) emits light like a concave lens. Since total internal reflection occurs at the boundary between the lead film (15) and the bubble (D), and the light incident on the center of the bubble passes through the inside of the bubble, the image of the bubble (D) is generally composed of a bright central disc and a dark ring surrounding it, allowing the bubble (D) to be identified.

[0062] Meanwhile, the collimated incident light can be irradiated parallel to the lead tab (20), and the divergence angle (θ) of the collimated light with respect to the optical axis can be adjusted by adjusting the focal length, position, and structure of the collimator (23). Light with an adjusted divergence angle (θ) can be irradiated so that scattering occurs more easily in defects present in the lead film (15) that induce abnormal scattering. Accordingly, by detecting the light transmitted parallel to the optical axis in the defect area where the light deviates from the direction of the optical axis due to scattering and the area transmitted without scattering, defects, i.e., bubbles and bubble outlines, can be clearly identified with high contrast compared to the normal area.

[0063] In addition, according to embodiments of the present invention, a distinct and clear edge contour with high contrast can be observed by irradiating a lead metal (13) with light collimated vertically and collecting the light transmitted through the edge of the lead metal (13) using an objective lens (29) having a small aperture angle (29a).

[0064] Referring again to FIG. 3, the image detector (31) detects light that has passed through the objective lens (29). The image detector (31) may include, for example, a camera. The image detector (31) captures an image of light that is incident within the aperture angle (29a) of the objective lens (29) among the light that has passed through the lead tab (20). The image detector (31) may include a CCD or CMOS image sensor, and may capture an image of the lead tab (20) using the image sensor. The image detector (31) may detect light in the visible region or near-infrared region.

[0065] The image processor (33) processes image information detected by the image detector (31) by applying a signal processing technique. The image processor (33) can generate an image to be displayed by performing various transformations such as geometric transformation, image matching, color correction, or color conversion of the image information detected by the image detector (31).

[0066] The image analyzer (35) can automatically detect defects such as bubbles by analyzing image information processed by the image processor (33). The image analyzer (35) can provide data on the size, shape, and distribution of defects such as bubbles by analyzing the image, and can determine whether the lead tab (20) is defective through machine learning.

[0067] The controller (37) controls each part within the system. The controller (27) can control the light source (21), the collimator (23), the image detector (31), the image processor (33), and the image analyzer (35). For example, the controller (37) can control the wavelength and light intensity of the light emitted from the light source (21), and can control the light emission time. For example, the controller (37) can control the light source (21) so that the light source (21) emits light of different light intensities for the same time or for different times. In addition, the controller (37) can control the divergence angle (θ) of the collimator (23). Furthermore, the controller (37) can control the image detector (31) to control the image detection time and the wavelength of the detected light, control the image processor (33) to process the detected image, and control the image analyzer (35) to perform image analysis.

[0068] Meanwhile, the lead tab (20) may include various regions (R1, R2, R3) depending on the magnitude of the transmittance. As shown in FIG. 5, the first region (R1) is a region exhibiting the highest first transmittance (T1), the second region (R2) is a region exhibiting a second transmittance (T2) lower than the first transmittance (T1), and the third region (R3) is a region exhibiting the lowest third transmittance (T3) due to the lead metal. The third transmittance (T3) may be zero as light is blocked by the metal.

[0069] The second region (R2) having a second transmittance (T2) is a region of the lead film (15) that is in contact with the lead metal. The second region (R2) is formed of the same material as the first region (R1), but may have a different transmittance from the first region (R1) by being modified by heat, etc.

[0070] When inspecting a lead film (15) containing regions with different transmittances by irradiating it with light of the same intensity, a problem may arise where defects can be clearly observed in one region but not in another region. To solve this problem, some embodiments of the present invention use a method of detecting defects by irradiating light with different light intensities according to transmittance.

[0071] FIG. 6 is a schematic graph for explaining a lead tab inspection method according to an embodiment of the present invention, FIG. 7a is a schematic diagram for explaining an image of a lead tab obtained by irradiating light with a first light intensity according to an embodiment of the present invention, FIG. 7b is a schematic diagram for explaining an image of a lead tab obtained by irradiating light with a second light intensity according to an embodiment of the present invention, and FIG. 7c is a schematic diagram for explaining an image of a lead tab obtained by aligning the image information of FIG. 7a and FIG. 7b.

[0072] First, referring to FIG. 6, the light source (21) irradiates light with a first light intensity (I1) and then irradiates light with a second light intensity (I2). The light of the first light intensity (I1) is at a first time (t 1-1 ~t 1-2 ) is irradiated for ), and light of the second light intensity (I2) is irradiated for the second time (t 1-2 ~t 1-3 ) can be investigated during. The first time and the second time may be continuous, as shown in FIG. 6, but the present invention is not limited thereto, and the first time and the second time may be discontinuous.

[0073] Light irradiation is completed for one lead tab (20), and for the next lead tab, the first time (t 2-1 ~t 2-2 Light of the first light intensity (I1) is irradiated during ) and during the second time (t 2-2 ~t 2-3During this time, light of a second light intensity (I2) can be irradiated. Through this light irradiation, inspection of all lead tabs (20) can be performed.

[0074] The first light intensity (I1) is an intensity suitable for detecting defects present in the lead film, such as abnormal deformation, scratches, and bubbles, while transmitting through or scattering within the first region (R1) of the lead film having the first transmittance (T1).

[0075] The second light intensity (I2) is an intensity suitable for detecting defects, such as bubbles, present in the second region (R2) of the lead film having the second transmittance (T2). The second light intensity (I2) is greater than the first light intensity (I1).

[0076] As shown in FIG. 7a, the first time (t 1-1 ~t 1-2 During this time, a first image (13i1) of the lead metal and a first image (15i1) of the lead film are obtained by irradiating light of a relatively small first light intensity (I1). In the first image (15i1) of the lead film, defects within a first region (R1) with high transmittance can be easily detected. However, because the light intensity is small, defects within a second region (R2) with low transmittance are not easily detected.

[0077] As shown in FIG. 7b, the second time (t 1-2 ~t 1-3 During this time, a second image (13i2) of the metal and a second image (15i2) of the lead film are obtained by irradiating light of a relatively large second light intensity (I2). In the second image (15i2) of the lead film, defects within the second region (R2) with low transmittance can be easily detected. However, because the light intensity is too large, light saturation occurs in the first region (R1) with high transmittance, so defects within the first region (R1) are not easily detected.

[0078] In some embodiments, the present invention can obtain a clear image (15i1) in a first region (R1) and a clear image (15i2) in a second region (R2) by irradiating light of different light intensities for different periods of time. Furthermore, by using image information of FIG. 7a and FIG. 7b to perform image matching, an image (15i) of a lead film combined with the first image (15i1) and the second image (15i2) can be obtained as shown in FIG. 7c. An image (13i) of the lead metal may be obtained by using the first image or the second image, or by matching these first and second images.

[0079] In this embodiment, it is described that light of the first light intensity (I1) is irradiated first and light of the second light intensity (I2) is irradiated later, but this order may be reversed.

[0080] In the present embodiment, the light having the first light intensity (I1) and the light having the second light intensity (I2) may be light of the same wavelength, but are not necessarily limited thereto.

[0081] FIG. 8 is a schematic graph illustrating a ret-tab inspection method according to another embodiment of the present invention.

[0082] Referring to FIG. 8, in the embodiment described with reference to FIG. 6, the light of the first light intensity (I1) and the light of the second light intensity (I2) are irradiated at different times, but in this embodiment, the light of the first light intensity (I1) and the light of the second light intensity (I2) are irradiated to the lead tab (20) for the same amount of time. However, the wavelengths of the light of the first light intensity (I1) and the light of the second light intensity (I2) may be different from each other.

[0083] For example, the light source (21) may emit light of at least two different wavelengths among blue, green, red light, and near-infrared light. Additionally, the image detector (31) may be equipped with a sensor capable of detecting each of the different wavelengths of light emitted from the light source (21). For example, the image detector (31) may be equipped with a Bayer RGB sensor or an RGB-NIR sensor.

[0084] According to the present embodiment, by simultaneously irradiating light of different wavelengths with different light intensities and detecting the light of these wavelengths respectively, images suitable for the first region (R1) and the second region (R2) can be obtained, and defects within the first and second regions (R1, R2) can be detected from each of these images. Additionally, these images can be aligned to display a final image.

[0085] According to the present embodiment, the inspection time can be shortened because the lead tab (20) is examined for the same amount of time.

[0086] FIG. 9 is a schematic cross-sectional view illustrating a ret tab inspection device according to another embodiment of the present invention.

[0087] Referring to FIG. 9, in this embodiment, the lead tab inspection device is similar to that described with reference to FIG. 3, but differs in that it includes a plurality of image detectors (31a, 31b) together with a beam splitter (30).

[0088] In one embodiment, the beam splitter (30) separates the wavelengths of light emitted from the light source (21). That is, the light source (21) may emit light of different wavelengths, and the beam splitter (30) separates the light of different wavelengths. For example, when light of different wavelengths is irradiated simultaneously as described with reference to FIG. 8, the beam splitter (30) may send the light of the first wavelength from these lights to the first image detector (31a) and the light of the second wavelength to the second image detector (31b). A clear image of the first region (R1) and the second region (R2) of the lead film can be obtained at the first image detector (31a) and the second image detector (31b), respectively. By aligning these images, an image of the lead tab (20) can be displayed.

[0089] In another embodiment, the beam splitter (30) may separate light intensity. For example, a light source (21) may irradiate light of light intensity (I1+I2), and the beam splitter (30) may separate light of first light intensity (I1') and second light intensity (I2') into light of second light intensity (I2') at the ratios of I1 / (I1+I2) and I2 / (I1+I2), respectively, as the light intensity is reduced to (I1'+I2) as it passes through the optical system and the lead tab (20). A first image detector (31a) may detect light of first light intensity (I1'), and a second image detector (31b) may detect light of second light intensity (I2') to obtain clear images of the first region (R1) and the second region (R2), respectively, and these images may be aligned to display an image of the lead tab (20). In this embodiment, the light of the first light intensity (I1') and the light of the second light intensity (I2') may be intensities suitable for observing the first region (R1) and the second region (R2).

[0090] In another embodiment, the beam splitter (30) may separate light intensity, but may also split light reduced to (I1'+I2') into ratios other than I1 / (I1+I2) and I2 / (I1+I2), as in the above embodiment. In this case, a neutral density (ND) filter, an iris diaphragm, an attenuator, etc., can be placed in front of the first image detector (31a) and / or the second image detector (31b) to adjust the light split by the beam splitter (30) to an intensity suitable for image detection in the first region (R1) and the second region (R2), respectively. Through this, the first image detector (31a) and the second image detector (31b) can obtain a clear image of the first region (R1) and the second region (R2), respectively, and the images can be aligned to display an image of the lead tab (20).

[0091] Although various embodiments of the present invention have been described above, the present invention is not limited to the various embodiments and features described above, and various modifications and changes are possible within the scope of the technical concept according to the claims of the present invention.

Claims

1. In a lead tab inspection device, A light source that generates light; A collimator that collimates light generated from the above light source into parallel light; An objective lens into which light transmitted through the above lead tab is incident; An image detector that detects light passing through the above objective lens; and It includes a controller that controls the above light source, and The above controller is a lead tab inspection device that controls the light source so that the light source emits light of different light intensities.

2. In Claim 1, The above objective lens is a lead tab inspection device composed of a telecentric lens.

3. In Claim 1, A lead tab inspection device in which light of different light intensities is emitted for different periods of time.

4. In Claim 1, The light source emits light of at least two different wavelengths, and A lead tab inspection device that emits light of different light intensities for the same amount of time.

5. In Claim 1, The above controller is a lead tab inspection device that controls the divergence angle of the above collimator.

6. In Claim 1, The above objective lens is a lead tab inspection device having an aperture angle less than or equal to the divergence angle of the above collimator.

7. In Claim 1, The above objective lens is a lead tab inspection device having an aperture angle of less than 10 degrees.

8. In Claim 1, Includes a beam splitter, The above image detector is a lead tab inspection device comprising a first image detector and a second image detector, each of which detects light separated from the beam splitter.

9. In Claim 8, The beam splitter is a lead tab inspection device that separates the wavelength or light intensity of light emitted from the light source.

10. In Claim 8, A lead tab inspection device further comprising an image processor that aligns images obtained from the first and second image detectors.

11. In Claim 1, An image processor that processes an image obtained through the above image detector; and A lead tab inspection device further comprising an image analyzer that analyzes an image processed by the above image processor.

12. In Claim 11, The above image detector detects a first image based on a first light intensity and a second image based on a second light intensity, and The above image processor is a lead tab inspection device that aligns the first image and the second image.

13. In Claim 11, The above image analyzer is a lead tab inspection device that automatically detects defects present in the lead tab by analyzing an image processed by the above image processor.

Images