KR102292463B1 - An Apparatus and Method for Inspecting Surface Defect using Image Sensor - Google Patents

Abstract

A surface defect inspection apparatus using an image sensor according to the present invention includes a frame part that provides a transport path of an object to be inspected along a longitudinal direction parallel to the ground, and installed on one side of the frame part to transport the object to be inspected along the transport path. The transfer unit, the image sensor unit installed in the middle of the transfer path to image the surface of the inspected object from the upper part of the transferred object, and the imaging area that is the area imaged by the image sensor unit among the surface of the inspected object It includes a plurality of illumination lamps irradiating light in different directions, an illumination unit installed in the middle of the transport path, and an imaging area for every imaging by imaging the surface of the inspected object while moving the inspected object by a predetermined unit transport distance. and a control unit for controlling operations of the conveying unit and the image sensor unit so as to be different by the unit conveying distance, wherein the control unit operates the illumination unit so that any one of the plurality of illumination lamps is turned on according to a predetermined sequence when the image sensor unit is imaged It is characterized in that light is irradiated from different directions to each of the image pickup regions continuously imaged with each other by controlling the .

Description

An Apparatus and Method for Inspecting Surface Defect using Image Sensor

The present invention relates to a surface defect inspection apparatus and inspection method using an image sensor, and more particularly, by capturing the surface of the inspected object with an image sensor while transferring the inspected object, obtains a scanned image of the entire surface of the inspected object, , any one of a plurality of illumination lamps having different light irradiation directions is lit according to a predetermined sequence for every imaging, and is configured to irradiate light to an imaging area imaged by the image sensor Since the scan image can be obtained for each lighting lamp of It relates to a surface defect inspection apparatus and inspection method using a sensor.

In general, in the case of flat products such as steel plates, PCB substrates, semiconductor wafers, and films, the surface for evaluating whether defects such as contaminant adhesion, scratches, dents, and cracks formed on the surface of the product after the manufacturing process is completed going through an inspection process.

Conventionally, it is common that the surface inspection process is performed in such a way that the inspector directly inspects the surface of the product using the naked eye or a microscope. Therefore, it is difficult to secure the reliability of uniform quality, and there is a problem that cannot be applied to the surface inspection of secondary batteries, semiconductor wafers, PCB substrates, etc. where minute surface defects have a fatal effect on quality.

In order to solve this problem, in recent years, a light source that irradiates light on the surface of the product under test and an image sensor that takes an image by the reflected light reflected from the surface of the product is used to determine whether a defect exists on the surface of the product. A surface inspection apparatus has been developed, and the surface inspection apparatus using such an image sensor is disclosed in detail in [Document 1] below.

However, in the case of surface defects, since the type, shape, and direction of the defect that can be detected through the output of the image sensor vary according to the direction in which light is irradiated, as in the technique according to the following [Document 1], the inspection surface is When a method of uniformly irradiating light is applied, there is a problem in that it is difficult to accurately detect surface defects having various types, shapes, or directions.

In order to solve this problem, the following [Document 2] discloses a method of improving the accuracy of a surface inspection by installing two light sources on the left and right sides of a transported object to take images while irradiating light in different directions.

However, in the case of the following [Document 2], since light can be irradiated only in two directions, front and rear, with respect to the scan line of the line scan type image sensor due to the limitation of the arrangement structure of the line type light source, various types, shapes, or directions There is still a disadvantage in that it is difficult to accurately detect all of the surface defects with the prior art.

In addition, in the case of the following [Document 2], since the scanning speed is slow because the line scan type image sensor is used, and because it is a method of overlapping scanning while alternately flashing two light sources for each scan line, the entire surface of the subject There is a problem that it takes an excessively long time to inspect the battery, and this problem is further aggravated when the subject has a large area and a full inspection is required due to the characteristics of the product, such as a secondary battery for an electric vehicle.

[Document 1] Korean Patent No. 10-0389967 (published on Feb. 27, 2002)

[Document 2] Korean Patent No. 10-0470402 (published on July 24, 2002)

The present invention is to solve the problems of the prior art as described above, an object of the present invention is to acquire a scan image of the entire surface of the subject by imaging the surface of the subject with an image sensor while transporting the subject, , any one of a plurality of illumination lamps having different light irradiation directions is lit according to a predetermined sequence for every imaging, and is configured to irradiate light to an imaging area imaged by the image sensor Since the scan image can be obtained for each lighting lamp of An object of the present invention is to provide a surface defect inspection apparatus and an inspection method using a sensor.

In order to achieve the above object, the apparatus for inspecting surface defects using an image sensor according to the present invention includes a frame unit that provides a transport path of an inspected object in a longitudinal direction parallel to the ground, and transports the inspected object along the transport path. a transfer unit installed on one side of the frame unit to make the image It includes a plurality of illumination lamps irradiating light in different directions with respect to an imaging area that is an area, a lighting unit installed in the middle of the transport path, and the surface of the inspected object while moving the inspected object by a predetermined unit transport distance and a control unit for controlling operations of the conveying unit and the image sensor unit so that the imaging area varies by the unit conveying distance for every imaging by imaging It is characterized in that light is irradiated from different directions to each of the imaging areas continuously imaged with each other by controlling the operation of the lighting unit to be turned on in accordance with the lighting conditions.

In addition, the illumination unit includes a plurality of illumination lamps irradiating light to the imaging area from the front of the image sensor unit, a first illumination module installed in the middle of the transport path, and the imaging area from the rear of the image sensor unit. a plurality of lighting lamps irradiating light, a second lighting module installed in the middle of the transport path, and a plurality of lighting lamps included in the first lighting module and the second lighting module by a control signal from the control unit and a lighting controller that lights up according to a predetermined order, wherein the plurality of lighting lamps provided in the first lighting module have different horizontal incident angles, which is an angle between a direction in which light is irradiated and a direction in which the subject is transported, respectively. and a plurality of lighting lamps provided in the second lighting module are also arranged so that the horizontal incident angles are different from each other.

In addition, the first lighting module has a sawtooth shape in which a first inclined surface and a second inclined surface facing the imaging area are continuously connected to each other along the width direction of the frame part, and the first lighting module side lamp is installed on the front side of the image sensor part. a member, a first lighting lamp including a plurality of LED light sources respectively coupled to the first inclined surface, and a second lighting lamp including a plurality of LED light sources respectively coupled to the second inclined surface, wherein the second lighting module comprises the The third inclined surface and the fourth inclined surface facing the imaging area have a sawtooth shape continuously connected to each other along the width direction of the frame part, and a first lighting module side lamp fastening member installed on one rear side of the image sensor part, each coupled to the third inclined surface It characterized in that it comprises a third lighting lamp consisting of a plurality of LED light sources, and a fourth lighting lamp consisting of a plurality of LED light sources respectively coupled to the fourth inclined surface.

In addition, the illumination unit includes a plurality of illumination lamps irradiating light to the imaging area from the front of the image sensor unit, a first illumination module installed in the middle of the transport path, and the imaging area from the rear of the image sensor unit. a plurality of lighting lamps irradiating light, a second lighting module installed in the middle of the transport path, and a plurality of lighting lamps included in the first lighting module and the second lighting module by a control signal from the control unit It is configured to include a lighting controller that lights up according to a predetermined order, wherein each of the plurality of lighting lamps provided in the first lighting module has an angle between a direction in which light is irradiated and a direction in which the image sensor unit captures the surface of the subject. It is characterized in that the vertical incidence angles are different from each other, and the plurality of illumination lamps provided in the second lighting module are also arranged so that the vertical incidence angles are different from each other.

In addition, the plurality of lighting lamps provided in the first lighting module are respectively arranged so that the horizontal incident angle, which is an angle between a light irradiating direction and a transport direction of the subject, is different from each other, and the plurality of lighting lamps provided in the second lighting module are different from each other. It is characterized in that the illumination lamps are also arranged so that the horizontal incident angles are different from each other.

In addition, the first lighting module has a first ramp and a second inclined surface facing the imaging area in a sawtooth shape continuously connected to each other along the width direction of the frame part, and a first lamp fastening member installed on a front side of the image sensor part; A second lamp fastening member configured to have the same structure as the first ramp fastening member and installed to be spaced apart from the first ramp fastening member on one side of the front side of the image sensor unit, a plurality of second ramp fastening members respectively coupled to the first inclined surface of the first ramp fastening member A first lighting lamp made of an LED light source, and a second lighting lamp comprising a plurality of LED light sources respectively coupled to a second inclined surface of the second lamp fastening member, wherein the second lighting module is a third lighting module facing the imaging area The inclined surface and the fourth inclined surface have a sawtooth shape continuously connected to each other along the width direction of the frame part, and have the same structure as the third lamp fastening member and the third ramp fastening member installed on the rear side of the image sensor part, and the image sensor part A fourth lamp fastening member installed to be spaced apart from the third lamp fastening member on one rear side, a third lighting lamp comprising a plurality of LED light sources respectively coupled to a third inclined surface of the third lamp fastening member, and the fourth lamp fastening member It characterized in that it comprises a fourth illumination lamp consisting of a plurality of LED light sources respectively coupled to the fourth inclined surface of the.

In addition, the unit transport distance is characterized in that it is determined by a value obtained by dividing the length of the imaging region with respect to the transport direction of the subject by the number of lighting lamps included in the first lighting module and the second lighting module.

In addition, the control unit sequentially synthesizes the captured images obtained when the corresponding lighting lamps are turned on for each of the plurality of lighting lamps to obtain a scanned image of the entire surface of the subject to be inspected, and for each of the plurality of lighting lamps It is characterized in that it is determined whether there is a defect on the surface of the inspected object by using the acquired scan image.

In addition, the surface defect inspection method using an image sensor according to the present invention is a surface defect inspection method using an image sensor installed in the middle of an object transport path and an image sensor using a plurality of lighting lamps, In the first step of transporting the subject by the unit transport distance, any one of the plurality of illumination lamps is turned on according to a predetermined order to irradiate light onto the imaging area, which is the area imaged by the image sensor, among the surface of the subject. The second step of performing the second step, the third step of imaging the imaging area from the upper part of the subject by using the image sensor, and the first to third steps until the imaging of the entire surface of the subject is completed. Repeated fourth step, using the captured image obtained in the fourth step, sequentially synthesizing the captured image obtained when the corresponding lighting lamp is turned on for each of a plurality of lighting lamps, and scanning the entire surface of the subject. A fifth step of obtaining a , and a sixth step of determining whether a defect exists on the surface of the inspected object using the scan image obtained for each of the plurality of illumination lamps, wherein the plurality of illumination lamps include It is characterized in that it is configured to irradiate light in different directions with respect to the imaging area.

The surface inspection apparatus and inspection method using an image sensor according to the present invention acquires a scanned image of the entire surface of the inspected object by imaging the surface of the inspected object with an image sensor while transferring the inspected object, but the light irradiation direction at every imaging Any one of the plurality of other lighting lamps is lit according to a predetermined sequence and configured to irradiate light to an imaging area imaged by the image sensor, so that for each of the plurality of lighting lamps, the inspection target when the lighting lamp is turned on Since a scan image of the entire surface of the cadaver can be obtained, there is an advantage in that the detection accuracy of defects having various types, shapes, or directions can be improved.

In addition, the surface inspection apparatus and inspection method using an image sensor according to the present invention is to light any one of a plurality of illumination lamps having different light irradiation directions in a predetermined order every time the image sensor scans the entire surface of the object to be imaged. Unlike the prior art of performing redundant scans on a plurality of light sources by being configured in this way, it is possible to obtain the scan images for each of a plurality of lighting lamps with different light irradiation directions with only one scan, so that the complete inspection like a secondary battery for a vehicle It has the advantage of significantly reducing the time required for surface inspection of a large-area subject.

1 is a perspective view for explaining the overall configuration of a surface defect inspection apparatus using an image sensor according to an embodiment of the present invention;
Figure 2 is a cross-sectional view of section AA of Figure 1 for explaining the configuration of the lighting unit;
3a and 3b are sectional views taken along line BB of FIG. 1 for explaining another modified example of the lighting unit, respectively;
Figure 4 is an enlarged view for explaining the configuration of the lighting module installed in the surface defect inspection device using the image sensor shown in Figure 1;
Figure 5 is a block diagram for explaining the operation configuration of the surface defect inspection apparatus using the image sensor shown in Figure 1;
Figure 6 is a view for explaining the operation of the lighting module installed in the surface defect inspection apparatus using the image sensor shown in Figure 1;
7 is a flowchart for explaining a surface defect inspection method by the surface defect inspection apparatus using the image sensor shown in FIG. 1, and
8 is a scan image of each of a plurality of illumination lamps obtained by the surface defect inspection apparatus using the image sensor shown in FIG. 1 .

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Figure 1 is a perspective view for explaining the overall configuration of a surface defect inspection apparatus using an image sensor according to an embodiment of the present invention, Figure 2 is a cross-sectional view taken along section AA of Figure 1 for explaining the configuration of the lighting unit, Figure 3a and 3B is a cross-sectional view taken along line BB of FIG. 1 for explaining another modified example of the lighting unit, respectively.

In addition, FIG. 4 is an enlarged view for explaining the configuration of a lighting module installed in the surface defect inspection apparatus using the image sensor shown in FIG. 1, and FIG. 5 is an operation of the surface defect inspection apparatus using the image sensor shown in FIG. It is a block diagram for explaining the configuration, and FIG. 6 is a view for explaining the operation of the lighting module installed in the surface defect inspection apparatus using the image sensor shown in FIG.

In addition, FIG. 7 is a flowchart for explaining a surface defect inspection method by the surface defect inspection apparatus using the image sensor shown in FIG. 1, and FIG. 8 is a surface defect inspection apparatus using the image sensor shown in FIG. It is a scanned image image of each of a plurality of lighting lamps.

A surface defect inspection apparatus using an image sensor according to the present invention is installed on one side of the frame part 10, which provides a transport path of the inspected object T, and the frame part 10, and the inspected object T along the transport path. ) conveying parts 31, 32, 33, an optical module support 20 installed on one side of the frame part 10 in the middle of the transport path, and a lighting part fixed to the optical module support 20 ( 40 and 50 ) and an image sensor unit 60 .

At this time, the frame part 10 may be configured as an example in a table shape with an upper surface parallel to the ground, and to provide a transport path through which the subject T is transported along the longitudinal direction of the upper surface as will be described later. An opening may be formed in the central portion of the upper surface.

In addition, the transfer units 31 , 32 , and 33 perform a function of transferring the subject T along the longitudinal direction (ie, transfer path) of the upper surface of the frame unit 10 . In this embodiment, as an example, the transfer unit (31, 32, 33) is a screw-shaped transport shaft 31 installed in the center of the upper surface of the frame portion 10, the coupling portion 32a on one side of the lower surface is the transport shaft through the coupling hole 32b in the center It may be configured to include a transfer plate 32 coupled to the 31 and on which the subject T is seated on the upper surface, and a transfer motor 33 for rotating the transfer shaft 31 .

At this time, it is preferable that bearing members (not shown) for fixing the conveying shaft 31 to be rotatable are installed on both sides of the frame part 10 in the longitudinal direction to which both ends of the conveying shaft 31 are coupled.

According to the configuration as described above, the conveying parts 31, 32, and 33 rotate the conveying shaft 31 coupled in the longitudinal direction to the center of the upper surface opening of the frame 10 by the conveying motor 33 while rotating the conveying shaft. By moving the transfer plate 32 coupled to 31 in the longitudinal direction (ie, transfer path) of the upper surface of the frame part 10 , the subject T seated on the upper surface of the transfer plate 32 is to be transported along the transport path.

In this embodiment, as an example, the transfer units 31, 32, 33 are configured in a rotating screw method by the transfer motor 33, but within the scope of performing the same function, any one of known transfer means such as a conveyor belt may be used. It can be preferably implemented using

In addition, in the drawings, for convenience of explanation, the frame portion 10 and the transfer units 31 , 32 , 33 are shown as transporting a single object T, but the speed and work efficiency of the surface defect inspection process are reduced. To this end, it is more preferable that the frame portion 10 and the transfer units 31 , 32 , and 33 are configured such that a plurality of objects T are continuously transferred while being spaced apart from each other.

In addition, the transfer motor 33 may be configured as a conventional electric motor, but as will be described later, a stepping motor capable of controlling the rotation angle of the motor to precisely control the unit transfer distance of the subject T. It is more preferable to do

In addition, the optical module support 20 is made of an approximately 'C' shape in which the upper ends of the vertical supports (not shown) perpendicular to both sides are connected by a horizontal support (not shown), the vertical support (not shown) is Each end is configured to be fixedly installed on both ends in the width direction of the upper surface of the frame portion (10).

On the other hand, the image sensor unit 60 is installed in the middle of the transport path by being fixed to the central part of the horizontal support (not shown) of the optical module support 20. By this configuration, the transport path is controlled as described above. The surface of the subject T is imaged from the upper part of the subject T being transported.

In this case, the image sensor unit 60 may be preferably implemented using an imaging device such as a CCD device. In the drawings, the image sensor unit 60 is shown as being cylindrical for convenience of illustration, but every imaging More preferably, it is formed in the shape of a bar having a long length in the width direction of the subject T so that the entire width direction of the transferred subject T can be imaged.

In addition, as described above, the image sensor unit 60 may be configured such that images are continuously captured according to a predetermined imaging cycle with respect to the subject T, which is continuously supplied while being spaced apart from each other. From when one end of the inspected object T, which is an inspection target, approaches the area where the image is captured by the image sensor unit 60 using a sensor (not shown), and the like, until the other end passes through the area where the image is captured The imaging may be configured to be performed according to the imaging cycle.

At this time, the imaging area IA, which is an area imaged by the image sensor unit 60 on the surface of the subject T, may vary depending on the characteristics of the imaging device. For convenience of explanation, in this embodiment, an example As the imaging area IA has a length indicated by a dotted line in FIG. 2 in the direction of the transport path and corresponds to the width of the subject T (or the width of the transport plate) in the width direction of the frame part 10 . It will be described as a region made of a rectangular shape having a length.

In addition, the illumination units 40 and 50 are configured to include a plurality of illumination lamps irradiating light in different directions with respect to the imaging area IA, specifically, in front of the image sensor unit 60 . A first illumination module 43 including a plurality of illumination lamps irradiating light to the imaging area IA, a plurality of lights irradiating light to the imaging area IA from the rear of the image sensor unit 60 a second lighting module 46 including a lamp, and a lighting controller 50 for lighting a plurality of lighting lamps included in the first lighting module 43 and the second lighting module 46 according to a predetermined order; is configured to include

At this time, the first lighting module 43 has a length corresponding to the width of the frame portion 10 and is formed in a plate shape inclined from the front of the image sensor unit 60 toward the imaging area IA. and the second lighting module 46 has a length corresponding to the width of the frame portion 10 and has a plate shape inclined toward the imaging area IA from the rear of the image sensor unit 60 . do.

As described above, the first and second lighting modules 43 and 46 configured to be symmetrical to each other in the front and rear directions (left and right directions in the drawing) of the imaging area IA have both ends of a pair of connecting plates, respectively. connected to each other by 47, and each connecting plate 47 is fixed to a vertical support (not shown) of the optical module support 20 by a pair of support plates 48, respectively, so that the middle of the transport path is installed on

In addition, the lighting controller 50 may be installed on one side of the optical module support 20, in this embodiment, as an example, is configured to be fixedly installed on one side of the vertical support (not shown).

In addition, the first lighting module 43 and the second lighting module 46 are each configured to include a plurality of lighting lamps. In this embodiment, for convenience of explanation, the first lighting module 43 and the second lighting module 46 are provided. A case in which the lighting module 46 includes two lighting lamps will be described as an example.

That is, on the lower surface of the first lighting module 43, the first lighting lamp 41 and the second lighting lamp 42 are vertically spaced apart from each other in the longitudinal direction (that is, in the width direction of the frame part). On the lower surface of the second lighting module 46, the third lighting lamp 44 and the fourth lighting lamp 45 are vertically spaced apart from each other in the longitudinal direction (that is, in the width direction of the frame part). do.

At this time, the first to fourth lighting lamps 41, 42, 44, 45 may be preferably implemented with various kinds of light sources, but in this embodiment, as an example, the lighting lamps 41, 42, 44,45) were composed of LED light sources.

In addition, since the first lighting lamp 41 and the second lighting lamp 42 are disposed so as to be spaced apart from each other in the vertical direction on the lower surface of the first lighting module 43 made of an inclined flat plate shape, each lighting The direction in which the lamps 41 and 42 irradiate light to the imaging area IA and the direction in which the image sensor unit 60 images the surface (ie, the imaging area) of the subject T (ie, in the drawing) The normal incidence angle, which is the angle between the upper surface of the transfer plate and the direction perpendicular to each other), is different from each other.

Also, in the case of the third lighting lamp 44 and the fourth lighting lamp 45 disposed to be spaced apart from each other on the lower surface of the second lighting module 46, the normal incidence angles are different from each other for the same reason.

As described above, each of the plurality of illumination lamps 41, 42, 44, and 45 included in the first illumination module 43 and the second illumination module 46 is disposed in the imaging area IA, as shown in FIG. The direction of irradiating light to each other is different.

On the other hand, the first illumination lamp 41 and the second illumination lamp 42 installed in the first illumination module 43 have a difference in normal incidence angle as described above, but irradiate light from the front of the imaging area IA. Since it is common in point and the difference in the normal incidence angle is not large due to the arrangement structure of the lighting lamps 41 and 42, when the first lighting lamp 41 and the second lighting lamp 42 are respectively irradiated for the same defect, the image sensor unit There is a point that it is difficult to generate a large difference between the captured images obtained in There is a possibility that it will not happen.

Accordingly, in order to improve this, in this embodiment, as another modification of the lighting unit, the directions in which the first lighting lamp 41 and the second lighting lamp 42 each irradiate light to the imaging area IA are further differentiated. 3A, between the direction in which the first illumination lamp 41 and the second illumination lamp 42 each irradiate light to the imaging area IA and the transport direction of the subject It was arranged so that the horizontal incident angle, which is the angle of , was different from each other.

In the case of this embodiment, for this purpose, the first lighting lamp 41 is arranged to irradiate light from the left to the right direction based on the transport direction of the subject as indicated by the dotted line in the drawing, and the second lighting lamp 42 is configured to be arranged to irradiate light from the right to the left with respect to the transport direction of the subject as indicated by the solid line in the drawing.

In addition, although not shown in the drawings, in the case of the third lighting lamp 44 and the fourth lighting lamp 45, the horizontal incident angle These were configured to be different from each other.

Specifically, the first lighting module 43 has a sawtooth shape in which a first inclined surface and a second inclined surface facing the imaging area IA are continuously connected to each other along the width direction of the frame part 10, and the image sensor The first lamp fastening member 41a installed on one side of the front side of the part 60 and the first lamp fastening member 41a have the same structure as the first lamp fastening member 41a and the first lamp fastening member on the front side of the image sensor unit 60 A first lighting lamp 41 comprising a second lamp fastening member 42a installed spaced apart from the 41a, a plurality of LED light sources 41b respectively coupled to the first inclined surface of the first lamp fastening member 41a; It is configured to include a second lighting lamp 42 made of a plurality of LED light sources 42b respectively coupled to the second inclined surface of the second lamp fastening member 42a.

Similarly, although not shown in the drawings, the second lighting module 46 is also in the shape of a sawtooth in which the third and fourth inclined surfaces facing the imaging area IA are continuously connected to each other along the width direction of the frame unit 10. A third lamp fastening member (not shown) installed on one rear side of the image sensor unit 60 , has the same structure as the third lamp fastening member (not shown), and the image sensor unit 60 has the A fourth lamp fastening member (not shown) installed spaced apart from the third lamp fastening member (not shown), and a plurality of LED light sources (not shown) coupled to the third inclined surface of the third lamp fastening member (not shown), respectively. A third lighting lamp (not shown) made of, and a fourth lighting lamp (not shown) made of a plurality of LED light sources (not shown) coupled to the fourth inclined surface of the fourth lamp fastening member (not shown), respectively. do.

At this time, the configuration of the second lighting module 46 is configured to be symmetrical with the first lighting module 43 in the front and rear directions (left and right in the drawing) of the imaging area IA as described above. The drawings will be omitted.

In addition, another modified example of the lighting unit is shown in FIG. 3B . The modified example is the first lighting lamp 41 , the second lighting lamp 42 , and the second lighting module 46 of the first lighting module 43 . ) of the third lighting lamp 44 and the fourth lighting lamp 45 are each coupled to a single lamp fastening member.

That is, as shown in FIG. 3B , in the first illumination module 43 , the first inclined surface and the second inclined surface facing the imaging area IA are teeth continuously connected to each other along the width direction of the frame part 10 . a first lighting module-side lamp fastening member 43a installed on one side of the front side of the image sensor unit 60, a first lighting lamp 41 comprising a plurality of LED light sources coupled to the first inclined surface, respectively; It is configured to include a second lighting lamp 42 made of a plurality of LED light sources respectively coupled to the two inclined surfaces.

Similarly, although not shown in the drawings, the second lighting module 46 is also in the shape of a sawtooth in which the third and fourth inclined surfaces facing the imaging area IA are continuously connected to each other along the width direction of the frame unit 10. A second lighting module-side lamp fastening member (not shown) installed on one rear side of the image sensor unit 60, a third lighting lamp (not shown) comprising a plurality of LED light sources coupled to the third inclined surface, respectively; It is configured to include a fourth lighting lamp (not shown) composed of a plurality of LED light sources respectively coupled to the four inclined surfaces.

At this time, the configuration of the second lighting module 46 is configured to be symmetrical with the first lighting module 43 in the front and rear directions (left and right in the drawing) of the imaging area IA as described above. The drawings will be omitted.

The lighting unit according to FIG. 3B configured as described above can reduce the overall device scale because the structure of the lighting unit (specifically, the width of the first and second lighting modules) can be slim in comparison with the lighting unit according to FIG. 3A described above. There are advantages that can be

As described in the various modified examples discussed above, each of the plurality of illumination lamps 41 , 42 , 44 , and 45 according to the present invention has very different directions for irradiating light with respect to the imaging area IA. The photographed images of surface defects having various types, shapes, and directions can be remarkably distinguished, thereby greatly improving the detection reliability of various surface defects of the subject.

On the other hand, the surface defect detection apparatus using the image sensor according to the present invention configured as described above transfers the inspected object T by a predetermined unit transport distance dL, as will be described later, on the surface of the inspected object T. By configuring the image to be captured, the image capturing area was changed by the unit transport distance dL for every image capturing.

In addition, the apparatus for detecting surface defects using an image sensor according to the present invention causes any one of the plurality of illumination lamps 41 , 42 , 44 , and 45 to be turned on in a predetermined order during imaging of the image sensor unit 60 . Light is irradiated from different directions to each of the imaging areas IA that are sequentially imaged.

At this time, in order to obtain a scanned image of the entire surface of the subject when sequentially synthesizing the captured images obtained for every image capturing, the unit transport distance dL is the image sensing area IA of the image sensor unit 60 . It is preferable to set the length equal to or smaller than the length in the transport direction.

In this embodiment, as an example, the unit transport distance dL is the length of the imaging area IA with respect to the transport direction of the subject T to the first illumination module 43 and the second illumination module 46 . It was configured to be determined as a value divided by the number of included lighting lamps (four in the case of this embodiment).

Accordingly, in the present embodiment, the first to fourth illumination lamps 41, 42, 44 and 45) are sequentially turned on and the process of irradiating the imaging area IA is repeatedly performed.

The apparatus for inspecting surface defects using an image sensor according to the present invention operates the image sensor unit 60 , the lighting controller 50 , and the transfer motor 33 using the timer unit 110 to configure the operation as described above. It is configured to further include a control unit 100 for controlling the.

At this time, the control unit 100 performs an imaging operation (or imaging cycle) of the image sensor unit 60 so that an image can be captured for the imaging area IA while transporting the subject T by a unit transport distance dL. ) and the transfer operation (or transfer period) of the subject T by the transfer motor 33 are synchronized with each other and operated.

In addition, the control unit 100 controls any one of the plurality of illumination lamps 41, 42, 44, and 45 in a predetermined order for each imaging operation (or imaging cycle) of the image sensor unit 60 in the imaging area ( The operation of the lighting controller 50 is controlled to irradiate light to IA).

In addition, when imaging of the entire surface of the subject T is completed, the control unit 100 illuminates the plurality of illumination lamps 41 , 42 , 44 , 45 using the image synthesizing unit 120 , respectively. By sequentially synthesizing the captured images obtained when the lamp is turned on, a scanned image of the entire surface of the subject T is obtained, and the plurality of illumination lamps 41, 42, 44, 45 The defect analysis unit 130 determines whether a defect exists on the surface of the object T using the scan image.

Next, a method of inspecting the surface defect of the subject T using the surface defect inspection apparatus using the image sensor according to the present invention described above with reference to FIG. 7 will be described.

First, the control unit 100 controls the transfer motor 33 to transfer the subject T along the transfer path by a predetermined unit transfer distance dL as described above (S10). As described above, the unit transport distance dL may be set to 1/4 of the length of the imaging area IA with respect to the transport direction of the object T.

In addition, when the step S10 is completed, the controller 100 controls the lighting controller 50 to light any one of the plurality of lighting lamps to irradiate the light to the imaging area IA (S20), In this case, the lighting controller 50 illuminates any one of the plurality of lighting lamps 41 , 42 , 44 , and 45 according to the order stored in advance in the memory to irradiate the light to the imaging area IA.

In this embodiment, as an example, as shown in FIG. 6 , the first illumination lamp 41 , the second illumination lamp 42 , the third illumination lamp 44 , and the fourth illumination lamp 45 are sequentially sequenced for every imaging. Light is irradiated to the imaging area IA.

In addition, when the step S30 is completed, the control unit 100 controls the image sensor unit 60 to capture the imaging area IA where light is irradiated from the upper portion of the subject T to obtain a captured image. (S30).

In addition, when the step S30 is completed, the control unit 100 determines whether the scan of the entire surface of the subject T is completed (that is, whether the imaging is completed) (S40), and the determination result of the step S40 If the scan is not completed, steps S10 and lower are repeatedly performed.

On the other hand, if it is determined in step S40 that the scan of the entire surface of the subject T is completed, the control unit 100 uses the captured images obtained in steps S10 to S40 to control the plurality of illumination lamps 41 , 42, 44, 45), a scan image of the entire surface of the subject T is obtained by sequentially synthesizing the captured images obtained when the corresponding illumination lamp is turned on (S50).

At this time, the scanned image for each lighting lamp may be made by the image synthesis unit 120, and on the right side of FIG. 8, each lighting lamp is actually inspected by the surface defect inspection apparatus and inspection method using the image sensor according to the present invention. The scanned image obtained for , is shown as an example.

In addition, when the step S50 is completed, the control unit 100 determines whether a defect exists on the surface of the inspected object T by using the scan image by the defect analysis unit 130 (S60), and if the defect is If it is determined that there is, the subject T is treated as defective (S70).

On the other hand, if it is determined that there is no defect as a result of the determination in step S60, the control unit 100 treats the subject T as a good product (S80).

At this time, the defect analysis unit 130 compares the scan image obtained by the image synthesis unit 120 with the scan image of the good product stored in advance for each of the lighting lamps 41, 42, 44, 45 as an example. It may be determined whether a defect exists on the surface of the object T.

As described above, the surface inspection apparatus and inspection method using an image sensor according to the present invention acquires a scanned image of the entire surface of the inspected object by imaging the surface of the inspected object with an image sensor while transferring the inspected object, Any one of a plurality of illumination lamps having different light irradiation directions is lit according to a predetermined sequence during imaging and is configured to irradiate light to an imaging area imaged by the image sensor, so that the corresponding illumination lamp is turned on for each of the plurality of illumination lamps Since it is possible to obtain a scan image of the entire surface of the inspected object at the time of being inspected, it is possible to improve the detection accuracy of defects having various types, shapes, or directions.

In addition, the surface inspection apparatus and inspection method using an image sensor according to the present invention is to light any one of a plurality of illumination lamps having different light irradiation directions in a predetermined order every time the image sensor scans the entire surface of the object to be imaged. Unlike the prior art of performing redundant scans on a plurality of light sources by being configured in this way, it is possible to obtain the scan images for each of a plurality of lighting lamps with different light irradiation directions with only one scan, so that the complete inspection like a secondary battery for a vehicle It can significantly reduce the time required for surface inspection of large-area objects.

10: frame part 31: feed shaft
32: transfer plate 33: transfer motor
43: first lighting module 46: second lighting module
50: lighting controller 60: image sensor unit
100: control unit 110: timer unit
120: image synthesis unit 130: image analysis unit

Claims (6)

a frame unit providing a transport path of the subject along a longitudinal direction parallel to the ground;
an optical module support installed on one side of the frame part in the middle of the transport path;
a transfer unit installed at one side of the frame unit to transfer the subject along the transfer path;
an image sensor unit installed in the middle of the transport path to image the surface of the inspected object from an upper portion of the transferred object;
and a plurality of illumination lamps irradiating light in different directions to an imaging area, which is an area imaged by the image sensor unit, among the surface of the object, and is fixedly installed on the optical module support in the middle of the transfer path lighting unit; and
A control unit for controlling the operation of the transfer unit and the image sensor unit so that the imaging area changes by the unit transfer distance for every imaging by imaging the surface of the subject while moving the subject by a predetermined unit transfer distance,
The transfer unit includes a screw-shaped transfer shaft installed in the center of the upper surface of the frame part, a transfer plate in which a coupling part on one side of the lower surface is coupled to the transfer shaft through a central coupling hole and the object to be inspected is seated on the upper surface, and the transfer shaft rotates including a transfer motor;
The optical module support is made of a 'C' shape in which the upper ends of the vertical supports perpendicular to both sides are connected by a horizontal support, and each end of the vertical support is fixed to both ends in the width direction of the upper surface of the frame part,
The illumination unit includes a first illumination module including a plurality of illumination lamps irradiating light to the imaging region from the front of the image sensor unit, and a plurality of illumination lamps irradiating light to the imaging region from the rear of the image sensor unit a second lighting module, a pair of connecting plates connecting both ends of the first and second lighting modules to each other, respectively, and a pair of supports for fixing the connecting plates to a vertical support of the optical module support, respectively Surface defect inspection apparatus using an image sensor, characterized in that it comprises a plate. In claim 1,
The first lighting module has a sawtooth shape in which a first inclined surface and a second inclined surface facing the imaging area are continuously connected to each other along the width direction of the frame part, and a first lighting module side lamp fastening member installed on a front side of the image sensor part; A first lighting lamp comprising a plurality of LED light sources respectively coupled to the first inclined surface, and a second lighting lamp comprising a plurality of LED light sources respectively coupled to the second inclined surface,
The second lighting module has a sawtooth shape in which a third inclined surface and a fourth inclined surface facing the imaging area are continuously connected to each other along the width direction of the frame part, and a second lighting module side lamp fastening member installed on a rear side of the image sensor part; Surface defects using an image sensor, characterized in that it comprises a third lighting lamp comprising a plurality of LED light sources respectively coupled to the third inclined surface, and a fourth lighting lamp comprising a plurality of LED light sources respectively coupled to the fourth inclined surface inspection device. In claim 1,
The first lighting module has a sawtooth shape in which a first inclined surface and a second inclined surface facing the imaging area are continuously connected to each other along the width direction of the frame part, and a first lamp fastening member installed on a front side of the image sensor part, the first A second lamp fastening member configured to have the same structure as the lamp fastening member and installed to be spaced apart from the first lamp fastening member on one front side of the image sensor unit, and a plurality of LED light sources coupled to the first inclined surface of the first lamp fastening member, respectively. a first lighting lamp made of
The second lighting module has a sawtooth shape in which a third inclined surface and a fourth inclined surface facing the imaging area are continuously connected to each other along the width direction of the frame part, and a third lamp fastening member installed on a rear side of the image sensor part, the third A fourth lamp fastening member configured to have the same structure as a lamp fastening member and installed to be spaced apart from the third lamp fastening member on one rear side of the image sensor unit, and a plurality of LED light sources coupled to a third inclined surface of the third lamp fastening member, respectively A surface defect inspection apparatus using an image sensor, comprising: a third lighting lamp made of In any one of claims 1 to 3,
The control unit controls the operation of the illumination unit so that any one of the plurality of illumination lamps is turned on according to a predetermined sequence during imaging by the image sensor unit, so that light is irradiated from different directions to each of the imaging areas continuously imaged with each other. A surface defect inspection device using an image sensor. In claim 4,
The unit transport distance is determined by dividing the length of the imaging area with respect to the transport direction of the subject by the number of lighting lamps included in the first and second lighting modules. Surface defects using an image sensor inspection device. In claim 5,
The control unit sequentially synthesizes the captured images obtained when the corresponding lighting lamp is turned on for each of the plurality of lighting lamps to obtain a scanned image of the entire surface of the subject, and the obtained for each of the plurality of lighting lamps A surface defect inspection apparatus using an image sensor, characterized in that it is determined whether a defect exists on the surface of the inspected object by using a scan image.

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