JP7411928B2 - Item photography device - Google Patents

Description

The present invention relates to an article photographing device that includes a plurality of light sources that illuminate an article and a camera that photographs the article.

Patent Document 1 discloses an apparatus for detecting defects present on the surface of an article such as a casting. This device sequentially and individually causes a plurality of light sources arranged around an article to emit light, and photographs the article with a camera each time the light is emitted, thereby acquiring a plurality of images under different photographing conditions. When a defect exists on the surface of an article, a shadow or reflection characteristic of the defect occurs. The device detects such shadows or reflections as defects.

JP2019-32268A

In the device of Patent Document 1, if a defect exists in a surface area that is a blind spot from the light source, the defect itself is included in the shadow, so no shadow or reflection due to the defect occurs. For this reason, defects existing in surface areas that are blind spots from the light source are difficult to detect.

The present invention has been made in consideration of such problems, and an object of the present invention is to provide an article photographing device that can illuminate a wide range of the surface of an article by minimizing the surface area that becomes a blind spot from the light source. shall be.

Aspects of the invention include:
An article photographing device comprising a plurality of light sources that illuminate an article, and a camera that photographs the article,
comprising a casing that surrounds an article space in which the article is placed by a light blocking member that blocks light;
At least one set of the light sources are arranged at positions facing each other across the article space.

According to the present invention, the number of surface areas that are blind spots from the light source is reduced, and the surface of the article can be illuminated over a wide range. Furthermore, variations in lighting conditions can be eliminated.

FIG. 1 is a perspective view showing a partial cross section of an article photographing device. FIG. 2 is a cross-sectional view taken along the line II--II in FIG. FIG. 3 is a cross-sectional view taken along the line III--III in FIG. FIG. 4 is a cross-sectional view taken along the line IV--IV in FIG. FIG. 5 is a diagram showing the height of the article, the radius of the container, and the radius of the support member.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The article photographing device according to the present invention will be described in detail below by citing preferred embodiments and referring to the accompanying drawings.

In the following, for convenience of explanation, two axes that are orthogonal to each other will be referred to as the X axis and the Y axis, and one axis that is orthogonal to the X axis and the Y axis will be referred to as the Z axis. The direction toward the + direction of the X-axis is defined as the X direction, and the direction toward the - direction is defined as the -X direction. Similarly, the direction towards the + direction of the Y-axis is the Y direction, the direction towards the - direction is the -Y direction, the direction towards the + direction of the Z-axis is the Z direction, and the direction towards the - direction is the -Z direction. do. In this embodiment, the Y direction is a vertically upward direction, and the -Y direction is a vertically downward direction.

[1. Configuration of article photographing device 10]
As shown in FIGS. 1 to 4, the article photographing device 10 includes a housing 12, a mirror body 14, a container 18, a support member 20, a plurality of light sources 22, and a plurality of cameras 24. . The article photographing device 10 includes an article space 30 as a position for placing an article 40 in an internal space of a casing 12, and simultaneously illuminates and photographs the article 40 placed in the article space 30 from one or more directions. Article 40 can be any object that is smaller than the interior space of container 18. The article 40 is assumed to be, for example, a vehicle part.

The casing 12 is a hexahedron assembled from plate-like members arranged in six directions (X direction, -X direction, Y direction, -Y direction, Z direction, -Z direction) with respect to the article space 30. . Each plate member is a light blocking member that blocks light, and is formed of, for example, colored resin (acrylic resin, etc.), metal, or the like. The housing 12 surrounds the container 18 with a light blocking member. A part of the housing 12, for example, a lid portion 12a (one side of a hexahedron) relatively disposed on the Y direction side, is detachable from the housing portion 12b (fifth side of a hexahedron).

The mirror bodies 14 are attached to the six inner surfaces of the housing 12. A mirror surface 14a of the mirror body 14 is directed toward the inside of the housing 12. It is preferable that the mirror body 14 covers the entire inner surface of the housing 12. The mirror body 14 scatters light incident from inside the housing 12 to the inside of the housing 12 .

The container 18 is a hollow sphere, and is made of a translucent member, such as resin (acrylic resin, etc.). Translucent here means that a part of the light incident from one side of the member is transmitted to the other side, but the shape of an object on one side of the member cannot be clearly seen from the other side. Transparency. A spherical space including an article space 30 is formed inside the container 18 . That is, the container 18 surrounds the article space 30 with a translucent member. The container 18 is placed on a transparent base 16 attached to the mirror body 14 on the −Y direction side. The center of the container 18 and the center of the housing 12 coincide. A part of the container 18, for example, an upper half body 18a disposed on the Y direction side is detachable from a lower half body 18b disposed on the −Y direction side.

The support member 20 is formed of a transparent plate-like member, for example, resin (acrylic resin, etc.). The outer peripheral shape of the support member 20 matches the inner peripheral shape of the container 18. When the inner circumferential shape of the container 18 is circular, the outer circumferential shape of the support member 20 is also circular. The support member 20 is housed inside the container 18 in a horizontal state. The support member 20 is held at an appropriate height inside the container 18 by the outer peripheral portion of the support member 20 coming into contact with the inner peripheral portion of the container 18 . The support member 20 supports the article 40 from the -Y direction side (lower side). The radius r of the support member 20 is set according to the height of the article 40. In this embodiment, in order to appropriately adjust the center position of the article 40, a plurality of support members 20 according to the height of the article 40, specifically a plurality of support members 20 with different radii r, are prepared in advance. .

The light source 22 is an LED that illuminates the article 40 placed in the article space 30. Each light source 22 is arranged between the housing 12 and the container 18. In this embodiment, the light source 22 is attached to the center position of each of the six mirror surfaces 14a. That is, the light source 22 attached to the mirror surface 14a on the X direction side and the light source 22 attached to the mirror surface 14a on the −X direction side face each other with the article space 30 in between. The light source 22 attached to the mirror surface 14a on the Y direction side and the light source 22 attached to the mirror surface 14a on the −Y direction side face each other with the article space 30 in between. The light source 22 attached to the mirror surface 14a on the Z direction side and the light source 22 attached to the mirror surface 14a on the −Z direction side face each other with the article space 30 in between. Each light source 22 is electrically connected to a lighting circuit (not shown).

Camera 24 is placed inside container 18 . In this embodiment, a plurality of cameras 24 are attached to the inner peripheral surface of the container 18 with their optical axes directed toward the article space 30. For example, as shown in FIG. 2, in an XY coordinate system whose origin is the center position of the container 18, one camera is placed at each of four positions on the inner peripheral surface of the container 18 where the elevation angle is 45 degrees. 24 is attached. In addition, as shown in FIG. 3, in the ZY coordinate system with the origin at the center position of the container 18, one camera is placed at each of four positions on the inner peripheral surface of the container 18 where the elevation angle is 45 degrees. 24 is attached. In addition, as shown in FIG. 4, in the XZ coordinate system with the center position of the container 18 as the origin, one camera is placed at each of four positions on the inner peripheral surface of the container 18 where the elevation angle is 45 degrees. 24 is attached. Each camera 24 is electrically connected to a control circuit (not shown).

[2. Photographing of article 40 - flow of inspection]
Before starting photographing, the lid 12a of the housing 12 is removed from the housing section 12b, and the upper half 18a of the container 18 is further removed from the lower half 18b. In this state, the interiors of the casing 12 and container 18 are opened. Next, a support member 20 suitable for the height of the article 40 to be photographed (inspected) is selected.

As shown in FIG. 5, if the height of the article 40 is H and the radius of the inner circumference of the container 18 is R, then the radius r of the support member 20 that allows the center of the article 40 to coincide with the center of the container 18 is r. is calculated by the following equation (1).

The support member 20 whose radius r is closest to the calculation result of the above equation (1) is selected. The selected support member 20 is held inside the container 18 with its outer peripheral portion abutting against the inner peripheral portion of the container 18 . The article 40 is placed at the center of the article space 30, that is, the upper surface of the support member 20. At this time, since an appropriate support member 20 has been selected, the center of the article 40 and the centers of the container 18 and the casing 12 generally coincide. Thereafter, the upper half 18a of the container 18 is attached to the lower half 18b, and the lid 12a of the housing 12 is attached to the accommodating section 12b.

When a photographer operates a photographing switch (not shown) of the article photographing device 10, current is supplied to the illumination circuit, and the plurality of light sources 22 emit light simultaneously and instantaneously. Furthermore, a photographing signal is output from the control circuit, and the plurality of cameras 24 simultaneously photograph the article 40. Each camera 24 outputs image data acquired through photography to a storage device (not shown).

After the photographing is completed, the lid part 12a of the housing 12 is removed from the housing part 12b, and the upper half 18a of the container 18 is further removed from the lower half 18b. In this state, the interiors of the casing 12 and container 18 are opened. Article 40 is removed from article space 30.

An inspection device (not shown) reads the photographed image data of the article 40 from the storage device, performs image recognition on the surface of the article 40, and determines the presence or absence of defects (scratches, dents, etc.).

[3. Illumination of article 40]
One set of light sources 22 illuminates the article 40 from two opposing directions (X direction side and -X direction side, Y direction side and -Y direction side, Z direction side and -Z direction side). can illuminate a wide area.

A portion of the light emitted from the light source 22 (referred to as first light) passes through the container 18 from the outer circumferential side to the inner circumferential side and enters the article 40 . Further, a part of the light emitted from the light source 22 (referred to as second light) is incident on one of the mirror surfaces 14a. Further, a part of the light emitted from the light source 22 (referred to as third light) is scattered on the outer peripheral surface of the container 18, or after passing through the container 18 from the outer peripheral side to the inner peripheral side, from the inner peripheral side to the outer peripheral side. and enters one of the mirror surfaces 14a. The light (second light and third light) incident on the mirror surface 14a is scattered. A portion of the scattered light passes through the container 18 from the outer circumferential side to the inner circumferential side and enters the article 40 . Further, a part of the scattered light enters one of the mirror surfaces 14a and is scattered again. In this way, the article 40 is illuminated by direct light (first light) emitted from the light source 22 and indirect light (second light and third light) scattered by the mirror surface 14a. Furthermore, since the light source 22 and the mirror surface 14a are arranged in all directions of the article 40, the entire surface of the article 40 is illuminated.

Since the housing 12 is formed of a light blocking member, environmental light outside the housing 12 does not pass into the interior of the housing 12. Further, the light emitted from the light source 22 does not pass through the outside of the housing 12 .

[4. Modified example]
The embodiments described above can be modified in various ways. For example, the lid portion 12a of the housing 12 may be openable and closable instead of being detachable from the housing portion 12b. Similarly, the upper half 18a of the container 18 may be openable and closable instead of being detachable from the lower half 18b.

The shape of the container 18 does not have to be spherical. For example, the container 18 may be a regular polyhedron made of a plurality of polygons. Alternatively, the number of faces of the regular polyhedron and the number of cameras 24 may match, and the cameras 24 may be attached to each face. Alternatively, the number of vertices of the regular polyhedron and the number of cameras 24 may match, and the cameras 24 may be attached to each vertex.

The number and arrangement of light sources 22 are not limited to the form described above. The light source 22 may be attached to a position other than the center position of the mirror surface 14a. However, at least two light sources 22 are required, and at least one set of light sources 22 must be arranged at positions facing each other with the article space 30 in between. Further, the light source 22 may be attached to the outer peripheral surface of the container 18 instead of being attached to the mirror surface 14a. Further, the light source 22 may be a xenon lamp instead of an LED.

The number and arrangement of cameras 24 are not limited to the form described above. The camera 24 only needs to be placed in front of the portion of the article 40 to be photographed. Alternatively, the main body of the camera 24 may be attached to the outer peripheral surface of the container 18, and the lens of the camera 24 may be inserted into a hole penetrating the container 18. The number of cameras 24 may be one. Furthermore, the camera 24 may be placed at a position other than between the pair of light sources 22 so that the camera 24 does not block the light (direct light) that directly enters the article 40 from the light sources 22 .

The base 16 may not be provided. In this case, the container 18 is held in a fixed position inside the casing 12 by having its outer peripheral surface abut against six surrounding mirror surfaces 14a.

[5. Invention obtained from embodiment]
The invention that can be understood from the above embodiments will be described below.

In an aspect of the invention,
An article photographing device 10 including a plurality of light sources 22 that illuminate an article 40 and a camera 24 that photographs the article 40,
A casing 12 that surrounds an article space 30 in which the article 40 is placed by a light blocking member that blocks light,
At least one set of the light sources 22 are arranged at positions facing each other with the article space 30 in between.

According to the above configuration, since the article 40 is illuminated by a pair of light sources 22 arranged opposite to each other, a shadow generated on the surface of the article 40 due to illumination from one side can be offset by illumination from the other side. . Therefore, the surface area that becomes a blind spot from the light source 22 is reduced, and the surface of the article 40 can be illuminated over a wide range. Further, the article 40 can be effectively illuminated with a minimum number of light sources 22. Further, according to the above configuration, since the casing 12 is formed of a light blocking member, the article 40 can be illuminated without being affected by environmental light outside the casing 12. In other words, variations in lighting conditions can be eliminated.

In an aspect of the invention,
A mirror body 14 that scatters incident light is provided inside the housing 12,
The mirror surface 14a of the mirror body 14 may be directed toward the article space 30.

According to the above configuration, the article 40 is not only directly illuminated by the light source 22 but also indirectly illuminated by the mirror body 14, so that the surface of the article 40 can be illuminated over a wider area, and the surface of the article 40 can be illuminated more widely. Shadows can be canceled over a wide range. Therefore, there are fewer surface areas that are blind spots from the light source 22, and the surface of the article 40 can be illuminated over a wider area.

In an aspect of the invention,
a container 18 surrounding the article space 30 and holding the camera 24 with the optical axis of the camera 24 directed toward the article space 30;
The housing 12 may surround the container 18 with the light blocking member.

In an aspect of the invention,
The container 18 may be spherical or polyhedral.

According to the above configuration, since the container 18 is a sphere or a polyhedron, it is easy to specify the relative position of the camera 24 with respect to an arbitrary position inside the container 18 (for example, the center position of the container 18).

In an aspect of the invention,
The container 18 may be translucent.

According to the above configuration, since the container 18 is translucent, light from outside the container 18 can be transmitted toward the article space 30 inside the container 18. It is possible to prevent the camera from being photographed.

In an aspect of the invention,
The container 18 may hold a plurality of cameras 24.

According to the above configuration, it is possible to obtain images of the article 40 taken from various directions, and further, by using the mutually adjacent cameras 24 as stereo cameras, it is possible to obtain a three-dimensional image of the article 40. .

In an aspect of the invention,
The apparatus may further include a transparent support member 20 that supports the article 40 from below and is movable in the height direction.

According to the above configuration, since the height position of the article 40 can be adjusted, the center of the article 40 and the center of the article space 30 can be made to substantially coincide regardless of the size of the article 40. Further, according to the above configuration, since the support member 20 is transparent, the article 40 can be photographed from all directions.

In an aspect of the invention,
The housing 12 is cubic,
Each side of the housing 12 may hold at least one of the light sources 22.

According to the above configuration, six sides of the article 40 can be illuminated, so that shadows are less likely to occur on the surface of the article 40.

Note that the article photographing device according to the present invention is not limited to the above-described embodiments, and can of course take various configurations without departing from the gist of the present invention.

12... Housing 14... Mirror body 18... Container 20... Support member 22... Light source 24... Camera 30... Article space 40... Article

Claims (6)

An article photographing device comprising a plurality of light sources that illuminate an article, and a camera that photographs the article,
a translucent container surrounding the article and holding the camera with the optical axis of the camera directed toward the article;
a casing that surrounds the article and the container with a light blocking member that blocks light ;
Equipped with
the camera is located inside the container;
each of the light sources is disposed between the housing and the container;
The at least two light sources are arranged at positions facing each other with the article in between. The article photographing device according to claim 1,
A mirror body that scatters incident light is provided between the housing and the container ,
A mirror surface of the mirror body is directed toward the inside of the container. The article photographing device according to claim 1 or 2 ,
The article photographing device, wherein the container is a sphere or a polyhedron. The article photographing device according to any one of claims 1 to 3 ,
The container is an article photographing device that holds a plurality of the cameras. The article photographing device according to any one of claims 1 to 4 ,
An article photographing device further comprising a transparent support member that supports the article from below and is movable in a height direction. The article photographing device according to any one of claims 1 to 5 ,
The casing is cubic,
Each surface of the housing holds at least one of the light sources.

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