JPH0575351B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention is applicable to the appearance of bottled products such as pharmaceuticals (vials, ambles), foods (drinking water), etc. This invention relates to an inspection illumination device for inspecting foreign matter that has a lower reflectance than the contents of a container.

[Conventional technology]

Illumination devices used for visual inspection of bottle products include, for example, Japanese Patent Application Laid-open Nos. 55-76942, 57-137844, and 57-182151. The illumination devices described in these publications all use translucent bottles and containers as objects to be inspected, and as shown in FIG. Transilluminate the bottle product 40 with a light source placed at (the direction of illumination is indicated by arrow A),
An image is taken by a camera 41 placed in front. Further, FIG. 6 is for inspecting the bottom of the bottle, and a light source 42 is placed below the bottle product 40, and an image is taken by a camera 43 from above.

On the other hand, as shown in FIG. 7, as another inspection lighting device, a reflective lighting device used for visual inspection of opaque objects to be inspected such as tablets has been proposed. (Special Application No. 1983-1983).
This illumination device uses an optical fiber bundle 47, a light receiving section 45 is arranged in front of a light source 44, and a plurality of branched light projecting sections 46 reflect and illuminate an object 48 to be inspected. Note that a diffused translucent member 49 is provided between the light projector 46 and the inspected object 48, and the image sensor 51 detects the inspected object 48 through a slit 50 provided on the upper part of the diffused translucent member 49. Take an image.

In this lighting device, the light projecting portion 46 of the optical fiber bundle 47 can be brought close to the object to be inspected 48 without being affected by heat, and as a result, the surface of the object to be inspected 48 can be illuminated with high brightness, and the branched Since the object to be inspected 48 can be illuminated from various angles by the optical fiber bundle 47, it is easy to create homogeneous illumination. moreover,
By allowing the light to pass through the diffused translucent member 49, even more uniform illumination can be achieved.

[Problem that the invention seeks to solve]

In order to perform high-speed visual inspection of products using a CCD camera, a lighting system is required that has high brightness and can provide optimal illumination according to the shape of the inspected object. In particular, when high-speed visual inspection is performed using a line sensor camera, the scanning period becomes short, and high-intensity and homogeneous illumination is required to obtain sufficient gain for inspection.

On the other hand, a device that directly illuminates the object to be inspected with an illumination lamp or the like does not provide the uniformity necessary for visual inspection. Furthermore, the light transmission type illumination device used in the bottle inspection apparatus shown in FIGS. 5 and 6 cannot perform a full surface inspection of a bottle container containing opaque contents.

On the other hand, using the light reflection type illumination device shown in FIG.
As shown in FIG. 8, when performing an appearance inspection of a bottle container 53 such as a vial containing a powdered injection drug 52, the powder 54, which is the content adhering to the wall of the bottle container 53, and defects 55 (dirt, foreign matter, etc.) are detected. There was a problem that it was difficult to tell the difference. That is, as shown in FIG. 9A, when a bottle container 53 with powder 54 and defects 55 attached to the wall surface is imaged by the image sensor 51 and image processed, a waveform as shown in FIG. 9B is obtained. The bottle 54 and the defect 55 were indistinguishable. Furthermore, since the amount of the powder injection 52 that is the content is not constant, it is difficult to distinguish between the powder injection 52 and the cavity 56 on the observed waveform when visually inspecting from the side, which is an obstacle to automating the inspection. .

In addition, in the appearance inspection of the bottle container 53, the 10th
As shown in FIG.
Powder 5 which is both opaque in the image processing waveform of Figure 0B
4 and defect 55, but since the two cannot be distinguished, the same problems as those when a light reflection type lighting device is used occur.

Such problems are not limited to pharmaceuticals such as the powder injection 52, but are common to visual inspections of all products containing contents in transparent or translucent containers.

Therefore, an object of the present invention is to be able to illuminate a product containing contents in a transparent or translucent container with high brightness and uniformly, and to eliminate defects such as powder adhering to the walls of the container. To provide an inspection illumination device that can discriminate the contents without making a mistake, and can also visually inspect the contents of the container and the cavity simultaneously without distinguishing them.

[Means for solving problems]

The inspection illumination device of the present invention is an inspection illumination device for inspecting foreign matter having a reflectance different from the contents in a translucent container as an object to be inspected, and has a light projecting section, and includes: an optical fiber bundle for reflected illumination, which bright-field illuminates the side of the container from the imaging side surface with a light projecting section to generate reflected light of the contents; an optical fiber bundle for transmitted illumination, which is disposed on the side and transmits through the cavity of the container to produce transmitted light having the same amount of light as the reflected light on the imaging side; Dark-field illumination is performed from both opposite sides, and the amount of light directed from the boundary toward the imaging side is adjusted from the boundary to the imaging side among the light from the optical fiber bundle for reflected illumination and the optical fiber bundle for transmitted illumination. An optical fiber bundle for auxiliary illumination is provided so that the amount of light directed toward the cavity is the same as the amount of light transmitted through the cavity.

[Effect]

According to the configuration of this invention, the following effects are achieved.

(a) The object to be inspected is bright-field illuminated from the imaging side and transmitted-illuminated from the opposite side to the imaging side, so that the amount of light reflected from the contents by bright-field illumination and the amount of light reflected from the imaging side of the transmitted-illumination are the same; When an image processing waveform is created using
Defects such as foreign matter that have a different reflectance than the contents will appear at a different level than the surroundings, so even if some of the powdery contents in the bottle are attached to the wall of the container, foreign matter etc. It becomes possible to distinguish between defects and contents such as powder.

(b) Using an optical fiber bundle for auxiliary illumination, dark-field illumination of the boundary of the contents in the container from both the imaging side and the opposite side is performed to determine the amount of light directed from the boundary towards the imaging side and for reflected illumination. Since the sum of the amount of light from the optical fiber bundle and the optical fiber bundle for transmitted illumination that goes from the boundary toward the imaging side is the same as the amount of transmitted light of the optical fiber for transmitted illumination, the image processing waveform Regarding the level, since the level of the boundary between the cavity of the container and the contents can be made the same as the level of the cavity, defects such as foreign objects can be easily inspected. In other words, the periphery of the boundary rises along the container toward the cavity and is not flush with the center of the boundary, so the amount of light decreases at the boundary and creates a shadow, but the auxiliary lighting light Fiber bundles can eliminate such shadows. Therefore, uniform illumination can be achieved regardless of the amount of contents in the container, making it possible to inspect the entire surface of the object to be inspected.

(c) The light projecting portion of each optical fiber bundle can be brought close to the object to be inspected to the extent that the illumination balance of the object to be inspected is not disrupted, and the surface of the object to be inspected can be illuminated with high brightness.

(d) The optical fiber bundle can be branched to form a plurality of light projecting parts, and the object to be inspected can be illuminated over a wide area, making it easier to obtain uniformity.

(e) Since the light source that sends light to the optical fiber bundle is separated from the object to be inspected via the optical fiber bundle, the object to be inspected is not affected by the heat from the light source.

〔Example〕

An embodiment of the present invention will be described based on FIGS. 1 to 4. FIG. 1 is an explanatory view showing one embodiment of the present invention, and FIGS. 2 and 3 are a side view and a plan view showing the three-dimensional arrangement of an optical fiber bundle.

As shown in FIG. 1, the object 1 to be inspected is placed on an inspection table 8. As shown in FIG. The object to be inspected 1 is a bottle container 4 containing a powder substance 2 such as a powder injection.
Some powder 2 and foreign matter 3 are attached to the upper wall surface of this bottle container 1.

On the imaging side of the inspected object 1, an optical fiber bundle 5 for reflected illumination and an optical fiber bundle 14 for auxiliary illumination are provided.
Further, on the opposite side, an optical fiber bundle 6 for transmitted illumination and an optical fiber bundle 15 for auxiliary illumination are provided, respectively. Further, a diffusely transparent member 9' is interposed between the optical fiber bundle 5 for reflected illumination and the object 1 to be inspected, and a diffusely transparent member 9' is also interposed between the optical fiber bundle 6 for transmitted illumination and the object 1 to be inspected. A photosensitive member 9 is interposed (see FIG. 3). These diffused and translucent members 9 and 9' are ordinary type paper, translucent plastic sheets, films, etc., and diffuse the light emitted from the optical fiber bundles 5 and 6, illuminating the object 1 to be inspected. It has the effect of making it more homogenized. Here, the diffused translucent member 9' interposed between the inspected object 1 and the reflected illumination optical fiber bundle 5 is not necessarily required, and may be omitted; It is preferable to provide such a diffused light-transmitting member 9' in order to prevent glare due to diffused reflection from the light source 1 and contribute to high-intensity illumination and uniform illumination per unit area.

The reflected illumination optical fiber bundle 5 includes a light receiving section 51
is arranged in front of the light source 10 and has two branched light projecting parts 5a, 5a, and these light projecting parts 5
At points a and 5a, bright-field illumination is applied to the powdery substance 2, which is the content, by directly illuminating the imaging side surface of the object 1 in parallel to the imaging direction. The optical fiber bundle 14 for auxiliary illumination on the imaging side shares the same light receiving section 51 and is branched from the optical fiber bundle 5 for reflected illumination, but it is connected to the hollow part of the bottle container 4 and the powdery object 2 such as a powder injection. The boundaries of the area are obliquely illuminated, that is, dark-field illuminated.

On the other hand, the optical fiber bundle 6 for transmitted illumination is connected to the light receiving section 11.
is placed in front of the light source 10'. Then, an image sensor detects the amount of light reflected from the injection agent by the optical fiber bundle 5 for reflected illumination, which enters the image sensor 13 on the imaging side, and the transmitted light transmitted through the cavity of the bottle container 4 by the optical fiber bundle 6 for transmitted illumination. The light source 10' and the light projecting section 6 are arranged so that the amount of light incident on the light source 13 is the same.
The position of a is adjusted. Further, the auxiliary illumination optical fiber bundle 15 shares the same light receiving section 11 and is branched from the transmitted illumination optical fiber bundle 6. This auxiliary illumination optical fiber bundle 15 also obliquely illuminates the boundary portion of the powdery material 2 of the object 1 with dark field illumination. Then, at the boundary part, transmitted light by the optical fiber bundle 6 for transmitted illumination,
The total amount of light incident on the image sensor 13 of the light reflected by the optical fiber bundle 5 for reflected illumination and the light reflected by the optical fiber bundles 14 and 15 for auxiliary illumination is transmitted through the cavity by the optical fiber bundle 6 for transmitted illumination. The optical fiber bundles 14, 1 for auxiliary illumination are arranged so that the amount of light incident on the image sensor 13 of transmitted light is the same as the amount of light incident on the image sensor 13.
The positions of the light projecting sections 14a and 15a of No. 5 are adjusted.

A mirror 12 is arranged in front of the object 1 on the imaging side, and an image sensor 1 is placed above the mirror 12.
3 is provided, and the inspected object 1 reflected by the mirror 12
image.

FIGS. 2 and 3 are a side view and a plan view, respectively, showing the three-dimensional arrangement of the optical fiber bundles 5, 6, 14, and 15 in this embodiment. As shown in these figures, the surface of the object to be inspected 1 on the imaging side is illuminated with bright field illumination by the light projecting parts 5a, 5a of the optical fiber bundle 5 for reflected illumination, and on both sides there are optical fiber bundles 14 for auxiliary illumination. , 14 light projecting units 14a are located. Also, on the opposite side of the object to be inspected 1, a third
As shown in the figure, the light projecting portion 6a of the optical fiber bundle 6 for transmitted illumination is located at a position linearly facing the imaging slit 17 provided in the diffusive translucent member 9' on the imaging side with the object 1 to be inspected in between. is provided, and each light projecting section 15a of the auxiliary illumination optical fiber bundles 15, 15 is located on both sides thereof.

The optical fiber bundle 5 for reflected illumination bright-field illuminates defects such as powdery substances 1 and foreign substances on the object 1 to be inspected from the imaging side by the image sensor 13, and the optical fiber bundle 6 for transmitted illumination illuminates the bottle container 2 from the opposite side. Trans-illumination of the cavity. At this time, by setting the amount of reflected light and the amount of transmitted light of the non-defective inspected object 1 equal, and by performing image processing on the imaged inspected object 1, a non-defective item cannot distinguish between the transmitted light and reflected light around it, but a non-defective item The presence of defects (dirt, foreign matter, etc.) that have a lower reflectance and therefore differ in brightness can be detected because the amount of reflected light is smaller than the amount of surrounding transmitted light. Therefore, even if powder, which is part of the contents of the object to be inspected 1, is attached to the container, it is easy to distinguish between the defect and the powder. In particular, by using the optical fiber bundles 5 and 6, the light projecting parts 5a and 6a can be brought close to each other to the extent that the illumination balance of the inspected object 1 is not disturbed, and the inspected object 1 can be illuminated with high brightness. , furthermore, the reflected illumination optical fiber bundle 5 has a plurality of branched light projecting parts 5.
a, 5a, and for reflected illumination from multiple directions,
Provides homogeneous resistance.

Further, the optical fiber bundles 14 and 15 for auxiliary illumination arranged on the imaging side of the object 1 to be inspected and the opposite side are connected to the imaging side and the opposite side of the object 1, as shown by arrows in FIG. They are arranged so that dark field illumination is applied to the boundary portions of the powdery material 2. Thereby, the total amount of light received by the image sensor 13 from the boundary can be adjusted to be the same as the amount of light transmitted through the cavity of the bottle container 4, so that the shadow of the boundary does not appear in the image processing waveform. Therefore, by illuminating the front surface of the object to be inspected 1 on the imaging side from the front and back, it is possible to uniformly illuminate the object 1 without causing shadows, regardless of the amount of contents. Therefore, it becomes possible to simultaneously inspect defects existing in the part of the inspection object 1 where the powdery substance 2 has entered.

In addition, since the optical fiber bundles 14 and 15 for auxiliary illumination are oblique illumination, there is no need to interpose a diffused light-transmitting member.

4A and 4B each show the relationship between the inspected object 1 and observed waveforms obtained by imaging and image processing the inspected object 1. FIG. In Fig. A, there are defects 3 in the part of the bottle container 4 containing the powdery substance 2 and in the cavity. At this time, the powdery substance 2 adheres to the wall surface of the cavity. In this state, Figure 1~
When the inspected object 1 is illuminated with the inspection illumination device shown in FIG. 3 and imaged with the image sensor 13 for visual inspection, the obtained waveform is as shown in FIG. 3B. In other words, the level of the waveform corresponding to the cavity part is due to the optical fiber bundle 6 for transmitted illumination, and the level of the waveform corresponding to the part where the powdery substance 2 has entered is due to the optical fiber bundle 5 for reflective illumination. It can be seen that both levels are the same. In addition, at the boundary of the part where the powdery material 2 is contained, a shadow will be created using only the optical fiber bundle 6 for transmitted illumination and the optical fiber bundle 5 for reflective illumination, that is, the level will be lowered, but the optical fiber bundles 14 and 15 for auxiliary illumination will cause a shadow. The boundaries are not visible because they are at the same level. In other words, the obtained waveform is uniform regardless of the amount of the powdery substance 2, which is the content, and cannot be distinguished because each particle of the powdery substance is at the same level, and only the presence 20 of the defect 3 is clearly shown. can be detected.

Note that this method can be applied not only when the reflectance of a defect such as a foreign object is smaller than the reflectance of the contents but also when the reflectance is larger. Further, the object 1 to be inspected is intermittently conveyed while rotating toward the inspection position, and is imaged and inspected over its entire circumference at the inspection position shown in FIG.

〔Effect of the invention〕

According to the configuration of the present invention, there are the following effects.

(a) The object to be inspected is bright-field illuminated from the imaging side and transmitted-illuminated from the opposite side to the imaging side, so that the amount of light reflected from the contents by bright-field illumination and the amount of light reflected from the imaging side of the transmitted-illumination are the same; When an image processing waveform is created using
Defects such as foreign matter that have a different reflectance than the contents will appear at a different level than the surroundings, so even if some of the powdery contents in the bottle are attached to the wall of the container, foreign matter etc. It becomes possible to distinguish between defects and contents such as powder.

(b) Using an optical fiber bundle for auxiliary illumination, dark-field illumination of the boundary of the contents in the container from both the imaging side and the opposite side is performed to determine the amount of light directed from the boundary towards the imaging side and for reflected illumination. Since the sum of the amount of light from the optical fiber bundle and the optical fiber bundle for transmitted illumination that goes from the boundary toward the imaging side is the same as the amount of transmitted light of the optical fiber for transmitted illumination, the image processing waveform Regarding the level, since the level of the boundary between the cavity of the container and the contents can be made the same as the level of the cavity, defects such as foreign objects can be easily inspected. In other words, the periphery of the boundary rises along the container toward the cavity and is not flush with the center of the boundary, so the amount of light decreases at the boundary and creates a shadow, but the auxiliary lighting light Fiber bundles can eliminate such shadows. Therefore, uniform illumination can be achieved regardless of the amount of contents in the container, making it possible to inspect the entire surface of the object to be inspected.

(c) The light projecting portion of each optical fiber bundle can be brought close to the object to be inspected to the extent that the illumination balance of the object to be inspected is not disrupted, and the surface of the object to be inspected can be illuminated with high brightness.

(d) The optical fiber bundle can be branched to form a plurality of light projecting parts, and the object to be inspected can be illuminated over a wide area, making it easier to obtain uniformity.

(e) Since the light source that sends light to the optical fiber bundle is separated from the object to be inspected via the optical fiber bundle, the object to be inspected is not affected by the heat from the light source.

(f) Since this inspection lighting device has a simple structure, it has the advantage that it can be manufactured easily and at low cost.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of one embodiment of the present invention, Figs. 2 and 3 are side and plan views showing the three-dimensional arrangement of the optical fiber bundle, and Figs. 4 A and B are the object to be inspected and its observed waveform. 5 is an explanatory diagram showing a conventional method for inspecting the body of a bottle, FIG. 6 is an explanatory diagram showing a conventional method for inspecting the bottom of a bottle, and FIG. 7 is an explanatory diagram showing a conventional method for inspecting the bottom of a bottle. Explanatory diagram of inspection lighting device, No. 8
The figure is an explanatory diagram showing the state in which the apparatus of Figure 7 is applied to the inspection of bottles and containers; Figures 9A and B are explanatory diagrams showing the inspected object and its observed waveform in the inspection apparatus shown in Figure 8; The figure shows the transmitted illumination of the object to be inspected and is an explanatory diagram of the observed waveform. 1...Object to be inspected, 5...Optical fiber bundle for reflected illumination,
6... Optical fiber bundle for transmitted illumination, 14, 15... Optical fiber bundle for auxiliary illumination.

Claims (1)

[Scope of Claims] 1. An inspection illumination device for inspecting foreign matter having a reflectance different from the contents in a translucent container as an object to be inspected, comprising a light projecting section and an optical fiber bundle for reflected illumination, which bright-field illuminates the side of the container from the imaging side surface in a light section to generate reflected light of the contents; and a light projecting section on the side opposite to the imaging side of the object to be inspected. an optical fiber bundle for transmitted illumination, which transmits through the cavity of the container and produces transmitted light having the same amount of light as the reflected light on the imaging side; Dark-field illumination is performed from both sides, and the amount of light traveling from the boundary toward the imaging side is the amount of light traveling from the boundary toward the imaging side among the light from the optical fiber bundle for reflected illumination and the optical fiber bundle for transmitted illumination. and an optical fiber bundle for auxiliary illumination, the amount of which is the same as the amount of light transmitted through the cavity. 2. The inspection illumination device according to claim 1, wherein a diffused translucent member is interposed between the container and the optical fiber bundle for transmitted illumination.