WO2011071035A1 - Appearance inspection device - Google Patents

Abstract

Provided is an appearance inspection device capable of accurately inspecting the pattern of even an object having projections and recesses on the surface thereof. The appearance inspection device is provided with a surface shape inspection means and a surface pattern inspection means which are disposed near a transfer path for transferring an object to be inspected (K). The surface shape inspection means is provided with a slit light image capturing unit (21, 51) for capturing an image formed by applying band-shaped slit light to the object to be inspected (K), and a shape determination unit for determining the acceptance or nonacceptance of the surface shape on the basis of the captured image. The surface pattern inspection means is provided with a gray-scale image capturing unit (41, 71) for capturing a gray-scale image by applying diffusion light to the object to be inspected (K), and a pattern determination unit for determining the acceptance or nonacceptance of the surface pattern on the basis of the captured gray-scale image. The pattern determination unit receives, from the shape determination unit, information relating to a region in which at least a portion having projections and recesses of the surface of the object to be inspected (K) is present, sets the received region to a non-inspection region, and determines the acceptance or nonacceptance of the pattern.

Description

Appearance inspection device

The present invention relates to an apparatus for inspecting the appearance of medicines (tablets, capsules, etc.), food, machine parts, electronic parts, etc. (hereinafter referred to as “inspection object”).

Conventionally, as an apparatus for inspecting the appearance of the surface of an inspection object, for example, apparatuses disclosed in Japanese Patent Application Laid-Open No. 63-53452 (Conventional Example 1) and Japanese Patent Application Laid-Open No. 2004-317126 (Conventional Example 2) are known. ing.

The inspection apparatus according to Conventional Example 1 exists on the surface of the inspection object by irradiating the surface of the inspection object with diffused light, appropriately imaging the surface with an imaging apparatus, and analyzing the obtained grayscale image. It detects smudges and printed parts and determines their suitability.

In this inspection apparatus, the surface of the object to be inspected is irradiated with diffused light so that the surface is uniformly illuminated from all directions, thereby eliminating irregularities existing on the surface, that is, generation of shadows due to the irregularities. It is possible to obtain a grayscale image that is suppressed and the surface pattern (dirt or printed portion) is emphasized.

On the other hand, the inspection apparatus according to Conventional Example 2 irradiates the surface of the inspection object with laser slit light, appropriately captures an image of the irradiated laser slit light, and analyzes the obtained image according to a light cutting method. To obtain information on the height of the surface of the inspection object, and based on the obtained height information, detect scratches or chips present on the surface of the inspection object, and determine the volume of the inspection object. It is to calculate.

Japanese Unexamined Patent Publication No. 63-53452 JP 2004-317126 A

However, among the inspection apparatuses according to the conventional example described above, the inspection apparatus according to the conventional example 1 has a problem as described below.

That is, as described above, the inspection apparatus according to Conventional Example 1 irradiates the surface of the inspection object with diffused light, thereby suppressing the occurrence of shadows due to the unevenness existing on the surface, and the pattern ( However, when there is a large unevenness on the surface, for example, a deep mark, there is a problem that the shadow cannot be completely erased.

In the case of a deep stamp, it is difficult to illuminate the inner surface of the stamp, especially the bottom, to the same extent as the surface, and as a result, a shadow image is generated on the bottom, and a dark and shaded image is captured. It is determined that the product is inferior although it has been given a simple stamp.

In particular, in the case of the above-mentioned pharmaceuticals, characters and the like are constantly stamped on the surface thereof, but the apparatus according to Conventional Example 1 cannot perform an accurate inspection.

On the other hand, since pharmaceuticals require a high level of assurance, it would be extremely useful if the inspection of the stamped portion and the surface stains could be accurately detected.

The present invention has been made in view of the above circumstances, and even if the surface has deep unevenness, the appearance inspection can accurately inspect defects such as the suitability of the unevenness and the stain on the surface. The purpose is to provide a device.

To achieve the above object, the present invention provides:
Transport means for transporting the inspection object along a predetermined transport path;
Surface shape inspection means for inspecting the surface shape of the inspection object conveyed by the conveyance means;
Similarly, an appearance inspection apparatus comprising a surface pattern inspection means for inspecting a surface pattern of the inspection object conveyed by the conveyance means,
The surface shape inspection means is disposed in the vicinity of the conveyance path, and irradiates the inspection object surface with a strip-shaped slit light so that an irradiation line thereof is orthogonal to the conveyance direction of the inspection object, and imaging light. An image when the slit light is irradiated onto the inspection object is taken from a direction whose axis is along the conveyance direction of the inspection object and intersects the optical axis of the slit light irradiated onto the inspection object. A slit light image capturing unit; and a shape determining unit that recognizes the shape characteristics of the surface of the inspection object based on the image captured by the slit light image capturing unit and determines suitability for the shape;
The surface pattern inspection means is disposed in the vicinity of the transport path upstream or downstream of the slit light image capturing unit, irradiates the surface of the inspection object with diffused light, and is illuminated with the diffused light. A grayscale image capturing unit that captures a grayscale image on the surface of the object, and a pattern for recognizing the pattern characteristics of the surface of the inspection object and determining whether the pattern is appropriate based on the grayscale image captured by the grayscale image capturing unit A determination unit,
Further, the pattern determination unit receives at least information on a region where the uneven portion on the surface of the inspection object exists from the shape determination unit, and the received region is inspected in a non-inspection region or other region where no inspection is performed. The present invention relates to an appearance inspection apparatus configured to set a low-sensitivity inspection region in which inspection is performed with a sensitivity lower than the sensitivity, and to determine suitability for the pattern.

According to the appearance inspection apparatus of the present invention, the surface shape of the inspection object conveyed by the conveying means is inspected by the surface shape inspecting means. That is, in the slit light image capturing unit, the surface of the inspection object is irradiated with a band-shaped slit light, and the reflected light is imaged. In the shape determination unit, the inspection target is obtained by, for example, a light cutting method based on the captured image. Data relating to the three-dimensional shape of the object surface is calculated, the feature of the surface shape is recognized from the calculated data, and the suitability is determined.

On the other hand, the surface of the inspection object is inspected by the surface pattern inspection means, the pattern characteristics of the surface are recognized based on the grayscale image captured by the grayscale image capturing unit, and its suitability is determined. For example, if there is dirt on the surface, the dirt is detected as a pattern, and as a result, it is determined to be defective, and if characters or the like are printed on the surface, this print part is detected as a pattern and the printing state The suitability is determined.

At that time, the pattern determination unit receives information from the shape determination unit about at least the region where the uneven portion on the surface of the inspection object exists, sets the received region as a non-inspection region or a low-sensitivity inspection region, Judgment of suitability for

When there are large irregularities on the surface, for example, a deeply engraved mark, it is difficult to illuminate the inner surface of the engraved mark, particularly the bottom, to the same extent as the surface even if the inspection surface is illuminated to some extent by diffuse illumination.

For this reason, a shadow is generated at the bottom, and the gray image capturing unit captures a gray image that is a relatively dark portion of the same, but as a result, a high-sensitivity inspection is performed in the pattern determination unit, for example, The threshold for determining whether or not it is a dark spot or the like based on the degree of dark color is set on the light color side, and even if a relatively light dark color portion exists, an inspection is performed to determine that this is a dark spot or the like In spite of the fact that the proper stamp is given, this is mistaken as a spot or the like and it is determined that the pattern is abnormal.

Therefore, in the present invention, the pattern determination unit relates to a region where at least uneven portions on the surface of the inspection object exist from the shape determination unit of the surface shape inspection means that can accurately determine the shape of the surface of the inspection object. Information is received, the received area is set as a non-inspection area or a low-sensitivity inspection area, and the suitability for the pattern on the surface of the inspection object is determined.

That is, if the region where the uneven portion is present is made a non-inspection region where the pattern inspection is not performed, it is possible to prevent the uneven portion from being erroneously determined as a spot or the like, and the pattern on the surface of the inspection object can be accurately determined. It becomes possible to inspect.

On the other hand, the inspection of the region where the uneven portion exists is inspected with a sensitivity lower than the inspection sensitivity in the other region, for example, the threshold value for determining whether it is a dark spot or the like from the degree of dark color is set to the dark side Even if it is a low-sensitivity test such that if there is a very dark part, the dark part will be distinguished from the uneven part and the dark part due to the spot. It is possible to accurately inspect the pattern on the surface of the inspection object. Further, in this way, when there is a very dark spot or the like in the uneven portion, it can be detected and selected, and the inspection accuracy can be improved compared to the case of non-inspection. .

In the present invention, any of the slit light image capturing unit and the gray image capturing unit may be provided on the upstream side, but considering the speed of processing in the pattern determining unit, the slit light image capturing unit is It is preferable to provide the process upstream of the shape determination unit before the process of the pattern determination unit, because the standby time does not occur in the process of the pattern determination unit.

Further, in the present invention, the slit light image capturing unit irradiates the slit light in a vertical direction, captures images from two directions on the upstream side and the downstream side in the transport direction of the inspection object, and determines the shape. The unit is configured to synthesize the two images captured by the slit light image capturing unit, and to recognize the shape feature of the surface of the inspection object based on the combined image and determine suitability for the shape. It is preferable.

When the imaging direction in the slit light image capturing unit is one direction, an image is not obtained for a surface existing at a position that is a blind spot with respect to the imaging direction, and the suitability of the three-dimensional shape for the surface is not obtained. However, if imaging is performed from two opposite directions, such blind spots can be minimized, and the suitability of the three-dimensional shape can be determined for substantially the entire surface.

As described above, according to the present invention, even if the object to be inspected is an object having irregularities on the surface, particularly an object having a deep marking, the surface pattern can be inspected accurately.

It is the front view which showed the whole appearance inspection apparatus which concerns on one Embodiment of this invention. FIG. 2 is a partial cross-sectional view in the direction of arrow AA in FIG. 1. It is explanatory drawing for demonstrating schematic structure of an A surface slit light image imaging part and a B surface slit light image imaging part. It is explanatory drawing for demonstrating schematic structure of an A surface grayscale image imaging part and a B surface grayscale image imaging part. It is a block diagram for demonstrating the structure of an inspection selection process part. It is explanatory drawing for demonstrating the irradiation state of the slit light in an A surface slit light image imaging part and a B surface slit light image imaging part. It is explanatory drawing for demonstrating the aspect of the image pick-up in an A surface slit optical image imaging part and a B surface slit optical image imaging part. It is explanatory drawing for demonstrating the aspect of the image pick-up in an A surface slit optical image imaging part and a B surface slit optical image imaging part. It is explanatory drawing for demonstrating the image imaged by the A surface slit light image imaging part and the B surface slit light image imaging part. It is explanatory drawing for demonstrating the process in A surface luminance data conversion process part and B surface luminance data conversion process part. It is explanatory drawing for demonstrating the process in an A surface 2 image composition process part and a B surface 2 image composition process part. It is explanatory drawing for demonstrating the process in an A surface shape feature extraction process part and a B surface shape feature extraction process part. It is explanatory drawing for demonstrating the process in an A surface shape determination process part and a B surface shape determination process part. It is explanatory drawing for demonstrating the problem of the blind spot in A surface slit light image imaging part and B surface slit light image imaging part. It is the front view which showed the whole external appearance inspection apparatus which concerns on other embodiment of this invention. It is a block diagram for demonstrating the structure of the test selection process part which concerns on other embodiment of this invention. It is explanatory drawing for demonstrating schematic structure of the gray image imaging part which concerns on other embodiment of this invention. It is explanatory drawing for demonstrating the process in the shape feature extraction process part and pattern determination process part which concern on other embodiment of this invention. It is explanatory drawing for demonstrating the process in the shape feature extraction process part and pattern determination process part which concern on other embodiment of this invention. It is explanatory drawing for demonstrating the process in the shape feature extraction process part and pattern determination process part which concern on other embodiment of this invention.

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

As shown in FIG. 1, the appearance inspection apparatus 1 of this example includes a supply unit 3 that supplies the inspection object K in an aligned manner, a first linear conveyance unit 10 that linearly conveys the supplied inspection object K, and a second one. Arranged in the vicinity of the conveying path of the A-side slit light image capturing unit 21 and the A-side gray image capturing unit 41 and the second linear conveying unit 15 arranged in the vicinity of the conveying path of the linear conveying unit 15 and the first linear conveying unit 10. The B surface slit light image capturing unit 51, the B surface grayscale image capturing unit 71, the inspection sorting processing unit 20, and the sorting unit 90 are provided.

In addition, as the inspection target K in this example, pharmaceuticals (tablets, capsules, etc.), foods, mechanical parts, electronic parts, and the like can be exemplified, but are not limited to these.

The details of each of the above parts will be described below.

The supply unit 3 includes a hopper 4 into which a large number of inspection objects K are loaded, a vibration feeder 5 that imparts vibration to the inspection object K that is discharged from the lower end of the hopper 4, and a conveyance end of the vibration feeder 5. Chute 6 that slides down the inspection object K discharged from the table, horizontally rotates, the alignment table 7 that discharges the inspection object K supplied from the chute 6 in a line, and a disk-shaped member that rotates in a vertical plane And a rotary conveyance unit 8 that adsorbs and conveys the inspection object K discharged from the alignment table 7 to the outer peripheral surface of the disk-shaped member, and aligns a large number of inspection objects K in a line. Then, the paper is sequentially transferred to the first linear conveyance unit 10.

The first linear conveyance unit 10 and the second linear conveyance unit 15 have the same structure, and the second linear conveyance unit 15 is disposed in an upside down state with respect to the first linear conveyance unit 10, and the first linear conveyance unit 10 has a transport path in the upper part thereof, and the second linear transport unit 15 has a transport path in the lower part thereof.

FIG. 2 is a partial cross-sectional view in the direction of arrows AA in FIG. 1 and shows the structure of the first linear transport unit 10. The reference numerals in parentheses correspond to the second linear transport unit 15. The member which carried out is shown.

As shown in FIG. 2, the first linear transport unit 10 is guided by side plates 11 and 12 arranged to face each other at a predetermined interval, and guide grooves formed on the upper surfaces of the side plates 11 and 12. And endless round belts 13 and 14 that run along the guide grooves. The space sandwiched between the side plates 11 and 12 is closed by the side plates 11 and 12 and other members (not shown) so that the upper portions thereof are opened, and maintained at a negative pressure by a vacuum pump (not shown).

Thus, when the space is maintained at a negative pressure, a suction force due to a negative pressure is generated between the round belts 13 and 14 traveling along the guide groove, and the inspection object K is moved to the round belts 13 and 14. When placed on the belt, it is sucked and sucked onto the round belts 13 and 14 by the suction force, and is transported in the running direction as the round belts 13 and 14 run.

The second linear transport unit 15 is the same, and includes side plates 16 and 17 and endless round belts 18 and 19, and the space between the side plates 16 and 17 is maintained at a negative pressure so that a round pressure is maintained. A suction force due to a negative pressure is generated between the belts 18 and 19, and the inspection object K is sucked and sucked by the round belts 18 and 19, and is conveyed in the traveling direction along with the traveling.

The conveyance start end of the first linear conveyance unit 10 is connected to the conveyance termination of the rotary conveyance unit 8, the conveyance termination end of the first linear conveyance unit 10 is connected to the conveyance start end of the second linear conveyance unit 15, and the first straight line The conveyance unit 10 sequentially receives the inspection object K from the rotary conveyance unit 8, sucks the lower surface (B surface), conveys it to the conveyance end, and delivers it to the second linear conveyance unit 15. Similarly, the 2nd linear conveyance part 15 receives the test object K sequentially from the 1st linear conveyance part 10, adsorb | sucks the upper surface (A surface), and conveys it to a conveyance termination | terminus.

The sorting unit 90 is provided at the transfer end of the second linear transport unit 15, and includes a sorting and collecting mechanism, a non-defective product collecting chamber, and a defective product collecting chamber (not shown), and according to a command from the inspection sorting processing unit 20 The sorting and collecting mechanism is driven, and the non-defective product is collected in the non-defective product collecting chamber and the defective product is collected in the defective product collecting chamber among the inspection object K transported to the transport end of the second linear transport unit 15.

As shown in FIG. 3, the A-side slit light image capturing unit 21 irradiates a camera 22 disposed above the transport path of the first linear transport unit 10 and slit light irradiation that irradiates a strip-shaped slit light L _1. a vessel 23, guides the slit beam L ₁ emitted from the slit beam irradiator 23 directly under the direction of the camera 22, a mirror 24, 25 to be irradiated on the transport path of the first linear conveyance unit 10, the conveying path The reflected light L ₂ of the irradiated slit light L ₁ is received from the upstream side in the transport direction (arrow direction) of the first linear transport unit 10 and guided to the camera 22, and the reflected light L ₃ and mirrors 28 and 29 for receiving the light ₃ from the downstream side in the transport direction and introducing it into the camera 22.

As shown in FIG. 6, the slit light irradiator 23 and the mirrors 24 and 25 divide the slit light L ₁ in the transport direction (arrows) of the inspection target K whose irradiation line is transported by the first linear transport unit 10. Irradiate vertically downward so as to be orthogonal to the indicated direction.

Then, the camera 22, as shown in FIG. 7, when the slit beam L ₁ is irradiated on the inspection object K being conveyed by the first linear conveyance unit 10, the reflected light L ₂ of the slit beam L ₁ , it received from the transfer direction (arrow direction) upstream of the inspection object K, capturing each image by receiving the reflected light L ₃ from the downstream side. When macroscopic from the two directions, but as shown in FIG. 8 (a) and (b), the camera 22 captures an image of the irradiation line of the slit light L ₁ as seen from the two directions. FIG. 7 shows the imaging form of the camera 22 in FIG. 3 as a simple and equivalent form that is easy to understand.

The camera 22 is an area sensor composed of elements arranged in double rows and double columns, and receives the reflected lights L ₂ and L ₃ to generate image data consisting of double row and double column pixels each having luminance data. To do.

An example of an image obtained by imaging one reflected light (for example, reflected light L ₂ ) is shown in FIG. As shown in the drawing, in the captured image, a part L _s corresponding to the surface of the inspection object K corresponds to a base part L _b where X is a direction orthogonal to the transport direction and Y is a transport direction. Is shifted to the Y direction (see also FIG. 8).

As shown in FIG. 7, this is caused by the fact that the imaging direction intersects with the irradiation direction of the slit light and is called a so-called light cutting method. For example, the image L _S corresponding to the surface of the inspection object K Looking at the pixel (X _i , Y _i ), the height of the surface of the inspection object K corresponding to the pixel (X _i ) from the base surface is the pixel (Y _j ) of the image L _b corresponding to the base surface. and based on the difference between the pixel (Y _i) of the image L _S, it can be calculated by geometric calculation techniques. In this example, the height of the surface of the inspection object K is not directly calculated, but the image captured by the camera 22 includes height information based on such a light cutting method.

Then, the image data captured in this way is transmitted from the camera 22 to the inspection selection processing unit 20. At that time, the camera 22 does not transmit all the image data in which all pixel positions (X _i , Y _i ) (i = 0 to n) and their luminance data are associated, as shown in FIG. The position data (X _i , Y _i ) composed of the pixel position (X _i ) in the X direction and the pixel position (Y _i ) having the maximum luminance in the column is transmitted to the inspection / selection processing unit 20 as image data. By doing so, the amount of data to be transmitted is reduced, the transmission speed and the processing speed in the inspection / sorting processing unit 20 can be increased, and rapid processing can be performed.

Further, the camera 22 captures the images in the two directions at a predetermined shutter speed, and at least the image data while the laser beam is irradiated on the upper surface of the inspection object K is used as a frame image obtained for each shutter. It transmits to the said inspection selection process part 20.

Thus, the A-side slit light image capturing unit 21 captures an image including height information of the upper surface (surface A) of the inspection object K, and transmits the image to the inspection / sorting processing unit 20.

The B-side slit light image capturing unit 51 includes a camera 52, a slit light irradiator 53, mirrors 54, 55, 56, 57, 58, 59 having the same configuration as the A-side slit light image capturing unit 21, and the A The surface slit light image capturing unit 21 is disposed in the vicinity of the second linear transport unit 15 in an inverted state. In FIG. 3, reference numerals in parentheses indicate corresponding members of the B-side slit light image capturing unit 51.

Thus, in the B-side slit light image capturing unit 51, similarly, the camera 52 irradiates the lower surface (B surface) of the inspection object K conveyed by the second linear conveyance unit 15. ₁ reflected light is received from two directions upstream and downstream of the conveyance direction of the inspection object K, and the image data (pixel position (X _i ) in the X direction) and has the maximum luminance in the column. Position data (X _i , Y _i )) consisting of pixel positions (Y _i ) is generated, and at least the image data while the lower surface of the inspection object K is irradiated with laser light is used as the frame image to perform the inspection selection. It transmits to the processing unit 20.

The A surface grayscale image capturing unit 41 is disposed on the downstream side in the transport direction from the A surface slit light image capturing unit 21, and as shown in FIG. 4, above the transport path of the first linear transport unit 10. A hemispherical diffusing member 44 that covers the conveying path and is disposed so that the inspection object K can pass therethrough, and is disposed outside the diffusing member 44, and irradiates light toward the inside of the diffusing member 44. A plurality of lamps 43 and a camera 42 provided above the diffusing member 44 and imaging the inside of the diffusing member 44 through an opening 44 a provided at the top of the diffusing member 44.

The light emitted from the lamp 43 is diffused when passing through the diffusing member 44, and becomes scattered light (diffused light) having no directivity to illuminate the space covered by the diffusing member 44. The upper surface (A surface) of the inspection object K carried into the diffusing member 44 by the first linear transport unit 10 is uniformly illuminated by the diffused light. And by uniformly illuminating the upper surface (A surface) in this way, even if the upper surface (A surface) is uneven, the entire surface is illuminated uniformly, and the upper surface is in a state in which the shading is emphasized. .

The camera 42 is composed of a line sensor or an area sensor, picks up a grayscale image of the upper surface (A surface) of the inspection object K carried into the diffusion member 44 by the first linear transport unit 10 at a predetermined shutter speed, The obtained image of at least the entire upper surface (A surface) is transmitted to the examination selection processing unit 20 as a frame image captured for each shutter.

Thus, in the A-side gray image capturing unit 41, the upper surface (A surface) of the inspection object K in a state where the light is uniformly illuminated by the diffused light and the gray level is more emphasized is captured and captured by the camera 42. The grayscale image is transmitted to the inspection selection processing unit 20.

The B-side gray image capturing unit 71 is disposed downstream of the B-side slit light image capturing unit 51 in the transport direction, and has the same configuration as the A-side gray image capturing unit 41, a diffusion member 74, a plurality of lamps 73, and a camera. 72 and is disposed in the vicinity of the second linear conveyance unit 15 in a state in which the upper and lower sides thereof are inverted with respect to the A-surface grayscale image capturing unit 41. In FIG. 4, reference numerals in parentheses indicate corresponding members of the B-side gray image capturing unit 71.

Thus, in the B-side gray image capturing unit 71, similarly, the lower surface (B surface) of the inspection object K conveyed by the second linear conveying unit 15 is diffused by the action of the lamp 73 and the diffusing member 74. The lower surface (B surface) in a state where the light is uniformly illuminated by light and the shade is more emphasized by the uniform illumination is imaged by the camera 72 through the opening 74a of the diffusing member 74, and at least the entire lower surface (B surface) imaged. These images are transmitted to the examination selection processing unit 20 as frame images captured for each shutter.

As shown in FIG. 5, the inspection / selection processing unit 20 includes an A-side shape determination unit 30, an A-side pattern determination unit 45, a B-side shape determination unit 60, a B-side pattern determination unit 75, and a selection control unit 91.

As shown in FIG. 5, the A-surface shape determination unit 30 includes an A-surface slit light image storage unit 31, an A-surface luminance data conversion processing unit 32, an A-surface 2 image composition processing unit 33, and an A-surface shape feature extraction process. Part 34 and A surface shape determination processing part 35.

The A-side slit light image storage unit 31 stores the bi-directional image data (frame images) received from the A-side slit light image capturing unit 21.

The A-plane luminance data conversion processing unit 32 reads out the two-direction frame images stored in the A-side slit light image storage unit 31 and performs the following processing to obtain the position data derived from the height component as its height. The image data is converted into luminance data set according to the component, and new image data in which the height component is expressed by the luminance data is generated.

Specifically, the A-plane luminance data conversion processing unit 32 first sequentially reads out the frame image data on one side, and based on the pixel position (X _i , Y _i ), as shown in FIG. The pixel position (Y _i ) corresponding to the depth component is converted into 256-gradation luminance data, image data composed of the pixel position (X _i ) and luminance data is generated, and sequentially converted for all frame images, New image data (image data composed of two-dimensional plane position data and luminance data representing height information at each position, hereinafter referred to as “luminance image data”) is generated. The luminance image data is generated in the same manner for the other side image data.

The A-side two-image composition processing unit 33 performs data conversion by the A-side luminance data conversion processing unit 32, and synthesizes newly generated two-direction luminance image data into one luminance image data. As can be seen from FIG. 7, when the inspection object K is imaged from an obliquely upper side on the upstream side in the transport direction, the reflected light at the front part of the inspection object K is weak, and when imaged from an obliquely upper side on the downstream side in the transport direction. Since the reflected light at the rear part of the inspection object K becomes weak, the image data for these parts becomes inaccurate.

FIG. 11A shows an image obtained by imaging the inspection object K of FIG. 7 from the upstream side in the transport direction by the A-surface luminance data conversion processing unit 32. Similarly, the downstream side in the transport direction FIG. 11B shows a converted image of the image captured from FIG. In FIG. 11A, the upper part of the image (the part surrounded by the white line) is inaccurate, and in FIG. 11B, the lower part of the image (the part surrounded by the white line) is inaccurate. Therefore, by combining these two images, for example, when data is missing between each other, the data that is present is applied, and when there is data between each other, the average value thereof is applied, whereby FIG. As shown in (c), an image in which the entire upper surface (A surface) of the inspection object K is accurately represented can be obtained.

Depending on the shape of the inspection object K surface, only than captured from one direction, but can not be completely receiving the reflected light of the laser beam L ₁ is about where the blind spot of the imaging direction, two directions By picking up an image from the above, it is possible to pick up such a blind spot portion from other directions, and in this sense, it is meaningful to pick up images from two directions.

For example, as shown in FIG. 14, when there is a missing portion 100 on the surface of the inspection object K, when the camera 22 captures an image from the direction indicated by the solid line, a blind spot portion 100 a is generated, but the opposite direction (in a two-dot chain line) If the image is taken from the direction shown), the blind spot 100a can be imaged.

The A-surface shape feature extraction unit 34 performs a process of extracting shape features based on the composite image generated by the A-surface two-image composition processing unit 33. Specifically, the synthesized image is smoothed by a so-called smoothing filter, and feature image data is generated by taking a difference between the obtained smoothed image data and the synthesized image data.

The synthesized image is obtained by converting the height component into luminance data, and the luminance represents the height of the upper surface (A surface) of the inspection object K. The upper surface is obtained by subtracting the averaged image from the synthesized image. An image in which a large amount of change in the height direction of (A surface) is emphasized can be obtained. For example, as shown in FIG. 12, by subtracting the smoothed image (FIG. 12B) from the composite image (FIG. 12A), as shown in FIG. And the number “678” stamped on the upper surface (A surface) are emphasized as dark portions. The A-surface shape feature extraction unit 34 transmits the feature image data generated in this way to the A-surface shape determination processing unit 35.

Further, the A-surface shape feature extraction unit 34 analyzes the generated feature image data, recognizes a region where the uneven portion exists in the image, and information on the recognized region will be described later. Send to.

The A-surface shape determination processing unit 35 compares this with data related to the appropriate surface shape based on the feature image related to the surface shape generated by the A-surface shape feature extraction unit 34, and determines whether or not the stamp is appropriate. Whether or not there is a chip or the like is determined.

The A-side pattern determination unit 45 stores the A-side grayscale image storage unit 46 that stores the grayscale image of the A-side received from the A-side grayscale image capturing unit 41 and the A-side grayscale image storage unit 46. An A surface grayscale image binarization processing unit 47 that binarizes the A surface grayscale image with a predetermined reference value, and an image portion corresponding to the upper surface (A surface) of the inspection object K from the binarized image. An A-side target part extraction processing unit 48 to extract, an A-side pattern feature extraction processing unit 49 to extract a black part (pattern part) in the extracted image, and the extracted black part (pattern part) as a predetermined reference It comprises an A-side pattern determination processing unit 50 that determines whether the pattern is good or bad.

The grayscale image captured by the A plane grayscale image capturing unit 41 and stored in the A plane grayscale image storage unit 46 is a multi-valued image, and this multivalued image is binarized with a predetermined reference value. An image portion corresponding to the upper surface (A surface) of the inspection object K is extracted from the binarized image, and a black portion (pattern portion) in the extracted image is further extracted to obtain a black portion (pattern portion). ) Is compared with a predetermined reference pattern, and the quality is determined.

For example, if there is no pattern such as printed characters on the upper surface (A surface) of the appropriate inspection object K, if there is an extracted black portion, it is determined that the spot is defective, and the printed characters are printed on the surface. If a pattern such as is attached, the extracted black part (pattern part) is compared with an appropriate pattern, and pass / fail is determined from the degree of adaptation.

At that time, the A-side pattern determination processing unit 50 receives information about the area where the uneven portion exists from the A-side shape feature extraction processing unit 34, and the feature image generated by the A-side pattern feature extraction unit 49. Of these, a region corresponding to the region where the uneven portion is present is set as a non-inspection region, and the quality determination is performed.

Even if the surface of the inspection object K has large unevenness, for example, a deep marking, even if the surface of the inspection object K can be illuminated to some extent by diffuse illumination using the lamp 43 and the diffusion member 44. Therefore, it is difficult to illuminate the inner surface of the engraving, particularly the bottom, to the same extent as the surface. Therefore, a shadow image is generated on the bottom, and the gray image where the same portion is dark is captured by the A-surface gray image capturing unit 41. Is done.

Therefore, in the image generated by the A-side pattern feature extraction processing unit 49 through the processing of the A-side grayscale image binarization processing unit 47 and the A-side target part extraction processing unit 48, the same bottom portion is black. An image is generated. FIG. 13A shows an image generated by the A-surface pattern feature extraction processing unit 49 when the surface of the inspection object K has a number stamp “678”. Note that black circles in the image are stigma on the surface of the inspection object K.

Therefore, when such an inscription exists on the surface of the inspection object K, the image data generated by the A-side pattern feature extraction processing unit 49 is used as it is, and the quality determination of the surface pattern is performed. Even a normally normal one is determined to be a pattern abnormality.

Therefore, in the present example, as described above, information about the area where the concavo-convex portion exists is received from the A-surface shape feature extraction processing unit 34, and the feature relating to the surface pattern generated by the A-surface pattern feature extraction unit 49 is received. In the image, an area corresponding to the area where the uneven portion is present is set as a non-inspection area, and the quality of the pattern is determined.

For example, when the feature image generated by the A-side pattern feature extraction processing unit 49 is as shown in FIG. 13A, the feature relating to the surface shape generated by the A-side shape feature extraction processing unit 34 If the image is an image as shown in FIG. 13B, the A-side pattern determination processing unit 50 determines that the area where the number “678” of the stamped part exists is a non-inspection area as shown in FIG. 13C. As shown in FIG. 13D, only black circles are inspected, and the quality is determined. In this example, the black circles are determined as bad spots.

Thus, the suitability of the pattern on the surface of the inspection object K can be accurately inspected by setting the uneven portion present on the surface of the inspection object K as the non-inspection area.

As shown in FIG. 5, the B surface shape determination unit 60 includes a B surface slit light image storage unit 61, a B surface luminance data conversion processing unit 62, a B surface 2 image composition processing unit 63, and a B surface shape feature extraction processing unit. 64 and B surface shape determination processing unit 65. The B-side slit light image storage unit 61 is the A-side slit light image storage unit 31, the B-side luminance data conversion processing unit 62 is the A-side luminance data conversion processing unit 32, and the B-side two image composition processing unit 63. Are the A-side 2 image composition processing unit 33, the B-side shape feature extraction processing unit 64 is the A-side shape feature extraction processing unit 34, and the B-side shape determination processing unit 65 is the A-side shape determination processing unit 35, respectively. It has the same configuration and performs the same processing. Thus, the B-side shape determining unit 60 detects the feature related to the shape of the lower surface (B-side) of the inspection object K, and determines its quality.

As shown in FIG. 5, the B surface pattern determination unit 75 includes a B surface gray image storage unit 76, a B surface gray image binarization processing unit 77, a B surface target part extraction processing unit 78, and a B surface pattern feature extraction. A processing unit 79 and a B-side pattern determination processing unit 80 are included. The B surface gray image storage unit 76 is the A surface gray image storage unit 46, the B surface gray image binarization processing unit 77 is the A surface gray image binarization processing unit 47, and the B surface target part extraction processing unit 78. Are the A-side target part extraction processing unit 48, the B-side pattern feature extraction processing unit 79 is the A-side pattern feature extraction processing unit 49, and the B-side pattern determination processing unit 80 is the A-side pattern determination processing unit 50, respectively. It has the same configuration and performs the same processing. Thus, the B-side pattern determining unit 75 detects the feature related to the pattern on the lower surface (B-side) of the inspection object K, and determines its quality.

The selection control unit 91 receives determination results from the A surface shape determination processing unit 35, the A surface pattern determination processing unit 50, the B surface shape determination processing unit 65, and the B surface pattern determination processing unit 80, respectively. When a failure determination result is received from at least one of the processing units, a sorting signal is transmitted to the sorting unit 90 at a timing when the inspection object K determined to be defective reaches the sorting unit 90. When receiving the sorting signal, the sorting unit 90 collects the inspection object K in the defective product collection chamber, and collects the conveyed inspection object K in the non-defective product collection chamber when the sorting signal is not received.

As described above in detail, according to the appearance inspection apparatus 1 of this example, the A surface is based on the image captured by the A surface slit light image capturing unit 21 while being transported by the first linear transport unit 10. The shape determination unit 30 inspects whether or not the shape of the upper surface (A surface) of the inspection object K is appropriate, and the A surface pattern determination unit 45 uses the same upper surface based on the image captured by the A surface grayscale image capturing unit 41. Appropriateness regarding the pattern of (A surface) is inspected, and then, while being transported by the second linear transport unit 15, the B surface shape determining unit 60 is based on the image captured by the B surface slit light image capturing unit 51. In FIG. 5, the suitability of the shape of the lower surface (B surface) of the inspection object K is inspected, and the lower surface (B surface) is determined by the B surface pattern determination unit 75 based on the image captured by the B surface grayscale image capturing unit 71. Suitable for the pattern of There is examined, and the upper and lower surfaces of the shape and pattern of the inspection object K is automatically inspected.

Then, when the A-side pattern determining unit 45 and the B-side pattern determining unit 75 extract the features related to the pattern and determine the suitability of the pattern, the A-side pattern determining unit 30 and the B-side pattern determining unit 60 Since the information about the area where the uneven portion exists is received, the area corresponding to the area where the uneven portion exists is set as the non-inspection area, and the quality of the pattern is determined. Even when uneven parts such as engravings are present on the front and back surfaces of the object K, the patterns on the upper and lower surfaces can be accurately inspected.

In addition, the A-side slit light image capturing unit 21 and the B-side slit light image capturing unit 51 capture images from two directions on the upstream side and the downstream side in the transport direction of the inspection target K, and the A-side shape determination unit 30 and B The surface shape determination unit 60 combines the two obtained images to generate one image, and determines whether the shape of the upper and lower surfaces of the inspection target K is appropriate based on the generated combined image. An image having as few blind spots as possible can be obtained, and the shape of the entire upper and lower surfaces can be accurately inspected.

In this example, the A-surface slit light image capturing unit 21 is provided upstream of the A-surface light / dark image capturing unit 41, so the A-surface slit light image storage unit 31 includes the A-surface light / dark image storage unit 46. Prior to this, data for the same inspection object K1 is stored. Therefore, the processes of the A plane luminance data conversion processing unit 32 to the A plane shape determination processing unit 35 are executed prior to the processes of the A plane gray image binarization processing unit 47 to the A plane pattern determination processing unit 50, and the A plane The pattern determination processing unit 50 can perform processing with reference to data from the A-surface shape feature extraction processing unit 34 without causing a waiting time, and can perform rapid processing.

Similarly, data for the same inspection object K1 is stored in the B-side slit light image storage unit 61 prior to the B-side grayscale image storage unit 76, and the B-side pattern determination processing unit 80 receives the waiting time. The processing can be performed with reference to the data from the B-surface shape feature extraction processing unit 64 without causing occurrence, and a quick processing can be performed.

However, when such a rapid process is not necessary, data for the same inspection object K1 is stored in the A-side slit light image storage unit 31 and the A-side gray image storage unit 46, respectively, and then the A-side The processing of the luminance data conversion processing unit 32 to the A surface shape determination processing unit 35 and the processing of the A surface grayscale image binarization processing unit 47 to the A surface pattern determination processing unit 50 may be executed simultaneously in parallel. Further, after the data for the same inspection object K1 is stored in the B-side slit light image storage unit 61 and the B-side gray image storage unit 76, the B-side luminance data conversion processing unit 62 to the B-side shape determination processing unit. The process of 65 and the processes of the B surface grayscale image binarization processing unit 77 to the B surface pattern determination processing unit 80 may be executed simultaneously in parallel.

In this case, the A-side gray image capturing unit 41 is disposed upstream of the A-side slit light image capturing unit 21, and the B-side gray image capturing unit 71 is disposed upstream of the B-side slit light image capturing unit 51. May be installed.

As mentioned above, although one embodiment of the present invention was described, the specific mode which can be taken by the present invention is not limited to this, and other modes can be taken without departing from the gist of the present invention.

For example, in the present invention, the significance of the surface that is the inspection target surface of the inspection target K is not limited to the upper surface (A surface) and the lower surface (B surface) shown in the above example, but the outer peripheral surface (side surface) thereof. It means the entire surface including.

Hereinafter, based on FIG. 15 to FIG. 20, it is configured to perform shape inspection and pattern inspection on the upper surface of the inspection object K, and side surface inspection viewed from the left and right sides in the conveyance direction of the inspection object K. The appearance inspection apparatus 100 will be described.

As shown in FIG. 15, the appearance inspection apparatus 100 includes a supply unit 3, a first linear conveyance unit 10, an A-side slit light image capturing unit 21 and a selection unit 90 having the same configuration as the above example, and an A-side slit light. The grayscale image pickup unit 130 disposed on the downstream side of the image pickup unit 21, and the inspection selection processing unit 110 that receives the image data from the A-side slit light image pickup unit 21 and the grayscale image pickup unit 130 and performs the inspection selection process. And.

The sorting unit 90 is provided at the transport downstream end of the first linear transport unit 10, and the inspection object K transported by the first straight transport unit 10 is in accordance with a command from the test sorting processing unit 110. Sort into good and defective products.

As shown in FIG. 17, the gray image capturing unit 130 has a configuration in which cameras 131 and 132 are newly provided in the A-side gray image capturing unit 41 of the above example. The camera 131 is disposed on the left side in the conveyance direction of the inspection object K, that is, on the paper surface, and the inspection object located in the diffusion member 44 through the opening 44b provided on the left side of the diffusion member 44. A grayscale image of the left side of K is captured. On the other hand, the camera 132 is disposed on the right side of the paper surface, and transmits a grayscale image of the right side surface of the inspection object K located in the diffusion member 44 through the opening 44c provided on the right side of the diffusion member 44. Take an image.

Thus, the grayscale image of the upper surface (A surface) of the inspection object K imaged by the camera 42, the grayscale image of the left side surface of the inspection object K imaged by the camera 131, and the inspection object imaged by the camera 132. The grayscale image on the right side of the object K is transmitted to the inspection sorting processor 110, respectively.

As shown in FIG. 16, the inspection / selection processing unit 110 includes an A-side shape determination unit 30, an A-side pattern determination unit 45, and a selection control unit 91, and a left side pattern determination newly provided in addition thereto. Unit 111 and right side surface pattern determination unit 120.

The left side pattern determination unit 111 includes a left side gradation image storage unit 112, a left side gradation image binarization processing unit 113, a left side target part extraction processing unit 114, a left side pattern feature extraction processing unit 115, and a left side pattern determination. Similarly, the right side pattern determination unit 120 includes a right side gray image storage unit 121, a right side gray image binarization processing unit 122, a right side target part extraction processing unit 123, and a right side pattern feature. An extraction processing unit 124 and a right side surface pattern determination processing unit 125 are included.

The left side gray image storage unit 112 and the right side gray image storage unit 121 are the A side gray image storage unit 46, the left side gray image binarization processing unit 113, and the right side gray image binarization processing unit 122 are the above. The A side grayscale image binarization processing unit 47, the left side target part extraction processing unit 114, and the right side target part extraction processing unit 123 are the A side target part extraction processing unit 48, the left side pattern feature extraction processing unit 115, and the right side. The surface pattern feature extraction processing unit 124 is a functional unit that performs the same processing as the A surface pattern feature extraction processing unit 49. Therefore, detailed description thereof is omitted here.

The A-surface shape feature extraction processing unit 34 of this aspect is present on the A-surface as a result of the analysis in addition to the above-described processing for analyzing the feature image data and recognizing the region where the uneven portion in the image exists. When it is determined that the uneven portion extends to the left side surface and / or the right side surface, in the image of the left side surface and / or right side surface imaged as described above, an area where the uneven portion is present Information on the calculated area is transmitted to the left side pattern determination processing unit 116 and / or the right side pattern determination processing unit 125.

For example, as shown in FIG. 18, when a dividing line G that opens to the outer peripheral surface is imprinted on the upper surface (A surface) of the inspection target K, the left side imaged by the camera 131 from the arrow C direction. In the surface image, as shown in FIG. 19, there is a possibility that the portion corresponding to the secant line G may be a dark color portion. Similarly, the image on the right side imaged by the camera 132 from the arrow D direction is displayed. However, there is a possibility that a dark color portion corresponding to the dividing line G as shown in FIG.

Therefore, the A-surface shape feature extraction processing unit 34 analyzes the feature image data and, for example, as shown in FIG. 18, the dividing line G that appears in the image on the left side with reference to the front end portion in the transport direction of the inspection object K. The position (l _a1 and l _a2 ) and the depth h _a thereof are calculated, and the position (l _b1 and l _b2 ) and the depth h _b of the secant line G appearing in the image on the right side are calculated. Information (l _a1 , l _a2 , h _a ) related to the left side pattern determination processing unit 116 and information related to the right side surface (l _b1 , l _b2 , h _b ) to the right side pattern determination processing unit 125. Send.

When the left side pattern determination processing unit 116 receives such information, as shown in FIG. 19, the area where the secant line G exists, that is, the area surrounded by the upper surface of the inspection object K and the two-point difference line. Is set as a non-inspection area, and the quality of the pattern as in the above example is determined.

Similarly, when the right side pattern determination processing unit 125 receives the above information, as shown in FIG. 20, the right side pattern determination processing unit 125 is surrounded by a region where the secant line G exists, that is, the upper surface of the inspection target K and a two-point difference line. The area is set as a non-inspection area, and the quality of the pattern is determined.

Thus, a defect determination result is received from any one of the A-surface shape determination processing unit 35, the A-surface pattern determination processing unit 50, the left-side pattern determination processing unit 116, and the right-side pattern determination processing unit 125. When output, a sorting signal is transmitted from the sorting control unit 91, and the inspection object K determined to be defective is collected by the sorting unit 90 in the defective product collection chamber.

As described above, according to the appearance inspection apparatus 100 of the present embodiment, when the unevenness existing on the upper surface of the inspection object K extends to the side surface, the information obtained from the shape inspection result of the upper surface is displayed on the side surface pattern. By using it for the inspection, it is possible to prevent erroneous determination due to the unevenness in the pattern inspection, and it is possible to increase the inspection accuracy on the side surface.

In addition, as a matter of course, the appearance inspection apparatus 100 according to the present embodiment can be configured to inspect the lower surface of the inspection object K in the same manner as the appearance inspection apparatus 1 described above.

In the above-described two examples, the pattern inspection in the inspection / separation processing units 20 and 110 is performed by setting the region where the uneven portion is present as the non-inspection region. However, the present invention is not limited to this. Absent.

For example, in the inspection selection processing units 20 and 110, the grayscale image binarization processing units 47, 77, 113, and 122 are deleted and processed as multi-valued images, and the pattern feature extraction processing units 49, 79, In 115 and 124, the region where the uneven portion is present is inspected at a sensitivity lower than the inspection sensitivity in the other regions. For example, the threshold value for determining whether it is a dark spot or the like from the degree of dark color is set to the dark side. The low-sensitivity inspection may be set such that a dark spot is determined if an extremely dark portion is present.

In this way, if there is a very dark spot or the like on the uneven portion, it can be detected and sorted, and the inspection accuracy can be improved compared to the case of non-inspection.

In the pattern inspection, the corners (edge portions) of images picked up by the gray image pickup units 41 and 71 may be unclear depending on the shape of the inspection object K. In this case, it may happen that the non-defective product is erroneously determined as a defective product in each of the pattern determination units 45 and 75.

Therefore, in order to solve such a problem, each of the pattern feature extraction processing units 49 and 79 analyzes the feature image to detect a region whose shape changes extremely, such as an edge portion of the inspection object K, Information regarding such areas may be transmitted to the pattern determination processing sections 50 and 80, and the pattern determination processing sections 50 and 80 may set such areas as non-inspection areas to perform pattern inspection.

DESCRIPTION OF SYMBOLS 1 Appearance inspection apparatus 10 1st linear conveyance part 15 2nd linear conveyance part 20 Inspection selection process part 21 A surface slit light image imaging part 30 A surface shape determination part 41 A surface grayscale image imaging part 45 A surface pattern determination part 51 B Surface slit light image capturing unit 60 B surface shape determining unit 71 B surface gray image capturing unit 75 B surface pattern determining unit 100 Appearance inspection device 110 Inspection selection processing unit 111 Left side surface pattern determining unit 120 Right side surface pattern determining unit 130 Gray image capturing Part

Claims (2)

Transport means for transporting the inspection object along a predetermined transport path;
Surface shape inspection means for inspecting the surface shape of the inspection object conveyed by the conveyance means;
Similarly, an appearance inspection apparatus comprising a surface pattern inspection means for inspecting a surface pattern of the inspection object conveyed by the conveyance means,
The surface shape inspection means is disposed in the vicinity of the conveyance path, and irradiates the inspection object surface with a strip-shaped slit light so that an irradiation line thereof is orthogonal to the conveyance direction of the inspection object, and imaging light. An image when the slit light is irradiated onto the inspection object is taken from a direction whose axis is along the conveyance direction of the inspection object and intersects the optical axis of the slit light irradiated onto the inspection object. A slit light image capturing unit; and a shape determining unit that recognizes the shape characteristics of the surface of the inspection object based on the image captured by the slit light image capturing unit and determines suitability for the shape;
The surface pattern inspection means is disposed in the vicinity of the transport path upstream or downstream of the slit light image capturing unit, irradiates the surface of the inspection object with diffused light, and is illuminated with the diffused light. A grayscale image capturing unit that captures a grayscale image on the surface of the object, and a pattern for recognizing the pattern characteristics of the surface of the inspection object and determining whether the pattern is appropriate based on the grayscale image captured by the grayscale image capturing unit A determination unit,
Further, the pattern determination unit receives at least information on a region where the uneven portion on the surface of the inspection object exists from the shape determination unit, and the received region is inspected in a non-inspection region or other region where no inspection is performed. An appearance inspection apparatus configured to determine whether or not the pattern is appropriate by setting in a low-sensitivity inspection region in which inspection is performed with a sensitivity lower than the sensitivity. The slit light image capturing unit irradiates the slit light in the vertical direction, and captures images from two directions on the upstream side and the downstream side in the transport direction of the inspection object,
The shape determining unit combines the two images captured by the slit light image capturing unit, and recognizes the shape feature of the surface of the inspection object based on the combined image to determine suitability for the shape. The visual inspection apparatus according to claim 1, wherein the visual inspection apparatus is configured as follows.

Images