JP7805255B2 - Foreign object detection device and foreign object detection method - Google Patents

Description

The present invention relates to a foreign object detection device and method for detecting foreign objects attached to a stopper member attached to a translucent container.

One example of a detection device that detects foreign objects in translucent containers is the detection device shown in Patent Document 1. The detection device in Patent Document 1 detects the quality of a vial based on the presence or absence of foreign objects in the vial while transporting it. In the detection device of Patent Document 1, to detect the lower part of the vial, light is shone on the vial from below, diagonally above, diagonally below, or from the side. To detect the upper part of the vial, light is shone on the vial from below or from the side. Then, using a camera installed according to the direction of light projection on the vial, image capture and pixel counting are processed in parallel to continuously inspect the entire vial from the top to the bottom for foreign objects.

Patent No. 3351910

However, with conventional detection devices such as those shown in Patent Document 1, when detecting foreign matter adhering to a stopper member attached to a container filled with a drug such as a freeze-dried drug, the drug that settles to the bottom of the container prevents the camera from capturing an image of the stopper member. As a result, the camera is unable to capture a clear image of the stopper member to detect foreign matter adhering to the back side of the stopper member, i.e., the surface inside the container.

Furthermore, when using conventional detection devices to detect foreign objects in a plug member with a deep back surface (for example, a plug member with a concave back surface), increasing the resolution to capture a detailed image of the back surface of the plug member using a camera results in a shallow depth of field (the depth of the front and back focus areas becomes shallow), making it impossible to capture the fine details of the back surface of the plug member. For example, if the back surface of the plug member is imaged by setting the focal position to the back part of the back surface of the plug member, the front part of the back surface of the plug member will be blurred.

As a result, there was a problem in that foreign matter adhering to the back surface of the plug member could not be accurately detected based on the image of the plug member captured by the camera.

The present invention aims to solve these problems and provide a foreign object detection device and method that can accurately detect foreign objects adhering to the back surface of a stopper member attached to a translucent container.

To achieve this object, the foreign matter detection device of the present invention is a detection device that detects foreign matter adhering to a stopper member attached to a translucent container, and includes an imaging unit that images the stopper member, and a detection unit that detects foreign matter adhering to the stopper member based on images of the stopper member captured by the imaging unit. The imaging unit images the back surface of the stopper member facing the inside of the container at multiple focal positions along the depth direction of the back surface at multiple first imaging positions formed on the bottom side of the container in a direction that forms a predetermined angle with respect to the axis of the container. The detection unit detects foreign matter adhering to the back surface of the stopper member based on the multiple images of the back surface of the stopper member captured by the imaging unit at the first imaging positions. The multiple focal positions include at least a focal position on the front side with respect to the back surface of the back surface of the stopper member and a focal position on the back side with respect to the back surface of the back surface of the stopper member. The depth between the front side and the back side with respect to the back surface of the back surface of the stopper member is deeper than the depth of field of the imaging unit .

According to the foreign object detection device of the present invention, it is preferable that the imaging unit captures images of the plug member attached to the container when the container is rotated to multiple angular positions around the axis.

According to the foreign object detection device of the present invention, it is preferable that the imaging unit images the side surface of the stopper member attached to the container at multiple second imaging positions formed in a direction forming a predetermined angle with respect to the axis of the container, and the detection unit detects foreign objects adhering to the side surface of the stopper member based on the multiple images of the side surface of the stopper member captured by the imaging unit from the multiple second imaging positions.

The foreign object detection method of the present invention is a method for detecting foreign objects adhering to a stopper member attached to a translucent container, and includes: an imaging step of imaging a back surface of the stopper member facing the inside of the container at a plurality of focal positions along the depth direction of the back surface at a plurality of first imaging positions formed on the bottom side of the container in a direction forming a predetermined angle with respect to the axis of the container; and a foreign object detection step of detecting foreign objects adhering to the back surface of the stopper member based on the plurality of images of the back surface of the stopper member imaged at the first imaging positions in the imaging step, wherein the plurality of focal positions include at least a focal position on the front side with respect to the back surface of the back surface of the stopper member and a focal position on the rear side with respect to the back surface of the back surface of the stopper member, and the depth between the front side and the rear side with respect to the back surface of the back surface of the stopper member is deeper than the depth of field of the imaging in the imaging step .

The foreign object detection device and foreign object detection method of the present invention can accurately detect foreign objects adhering to the back surface of a plug member from an image of the back surface of the plug member captured by the imaging unit.

1 is a schematic diagram showing the overall configuration of a foreign object detection device according to an embodiment of the present invention; 10 is a diagram showing an image of the back surface of the rubber stopper captured by the camera of the detection device. FIG. 10 is a diagram showing an image of the back surface of the rubber stopper captured by the camera of the detection device. FIG. 10 is a diagram showing the positional relationship between the camera of the detection device and the container (rubber stopper) when the camera captures an image of the back surface of the rubber stopper. FIG. 10 is a diagram showing the positional relationship between the camera of the detection device and the container (rubber stopper) when the camera captures an image of the side of the rubber stopper. FIG. 10 is a flowchart showing a method for detecting foreign matter adhering to the back surface of a rubber plug using the detection device. 10 is a flowchart showing a method for detecting foreign matter adhering to the side surface of a rubber stopper using the detection device.

The foreign object detection device and foreign object detection method according to the embodiment will be described below with reference to the drawings.

As shown in FIG. 1, the detection device 10 in this embodiment is a device that detects foreign matter G (see FIGS. 2A and 2B) adhering to a rubber stopper 91 (an example of a "stopper member") attached to a container 90. The container 90 to which the rubber stopper 91 is attached is a cylindrical container that is translucent. The container 90 is made of, for example, glass. The container 90 is filled with a drug such as a freeze-dried agent, leaving a space near the rubber stopper 91.

The rubber stopper 91 is attached to the mouth 90a of the container 90. The rubber stopper 91 comprises a main body 92 that closes the opening at the top of the mouth 90a, and a leg 93 that is formed integrally with the main body 92 and inserted into the mouth 90a. The main body 92 is formed in the shape of a circular plate. The leg 93 is formed in a cylindrical shape.

The tip surface of the leg 93 forms the back surface 93a of the rubber stopper 91. The side surface of the leg 93 forms the side surface 93B of the rubber stopper 91. The back surface 93a of the rubber stopper 91 is the surface formed at the bottom end of the leg 93 when the leg 93 is inserted into the mouth 90a of the container 90. The side surface 93B of the rubber stopper 91 is the surface that faces the inner wall surface of the mouth 90a of the container 90 and is pressed against the inner wall surface when the leg 93 is inserted into the mouth 90a of the container 90. While the leg 93 is formed cylindrically, the back surface 93A of the rubber stopper 91, including the back surface 93a, is formed concavely toward the back side (interior) of the rubber stopper 91. In other words, the back surface 93A of the rubber stopper 91 has depth. The back surface portion 93A, including the back surface 93a of the rubber stopper 91, is the portion that is formed toward the inside of the container 90 when the leg portion 93 is inserted into the mouth portion 90a of the container 90.

The detection device 10 mainly comprises a camera 11 (an example of an "imaging unit") that captures an image of the container 90, a holding device 12 that holds the container 90, and a control device 20 that controls the entire detection device 10. The detection device 10 detects foreign matter G (see Figures 2A and 2B) adhering to the rubber stopper 91 based on the image of the container 90 (rubber stopper 91) captured by the camera 11.

The camera 11 is configured, for example, as a CCD camera. The camera 11 is fixed to a predetermined position on the detection device 10. The camera 11 is positioned so that its optical axis K is tilted upward at a predetermined angle θ with respect to the horizontal. The camera 11 captures images of the back surface 93A, including the back surface 93a, of the rubber stopper 91 attached to the container 90, and the side surface 93B of the rubber stopper 91 attached to the container 90.

To increase the resolution and capture detailed images of the back surface 93A and side surface 93B of the rubber stopper 91, the camera 11 increases its focal length and also enlarges the object (the back surface 93A and side surface 93B of the rubber stopper 91) (shortens the working distance) to capture the image. However, when the camera 11 increases its focal length and shortens the working distance to capture images of the back surface 93A and side surface 93B of the rubber stopper 91, the depth of field of the camera 11 becomes shallow (the depth of the front and rear focus areas becomes shallow), and it becomes impossible to capture detailed images of the back surface 93A and side surface 93B, including the back surface 93a of the rubber stopper 91.

In particular, the back surface 93A of the rubber stopper 91 has a depth that is concave toward the rear (interior) side due to its cylindrical shape, etc. The depth between the front and rear sides of the back surface 93a is greater than the depth of field of the camera 11. Therefore, when the camera 11 sets the first focal position 80a further back than the back surface 93a of the rubber stopper 91 and captures the back surface 93a of the rubber stopper 91, as shown in the first image 80 of Figure 2A, the back surface 93a of the rubber stopper 91 is captured blurred. Note that in the first image 80 and the second image 81, the light-colored lines indicate out-of-focus (blurred) areas, and the dark-colored areas indicate in-focus areas. Therefore, the camera 11 cannot increase the resolution to capture foreign matter G adhering to the back surface 93a of the rubber stopper 91 using only the first focal position 80a. Therefore, foreign matter G adhering to the back surface 93a of the rubber stopper 91 cannot be detected based on the first image 80 of the inner side of the back surface 93a of the rubber stopper 91 captured by the camera 11.

The camera 11 therefore sets multiple (two) focal positions (first focal position 80a, second focal position 81a) to capture an image of the back surface 93a of the rubber stopper 91. Specifically, as in the first image 80 of FIG. 2A, the camera 11 sets the first focal position 80a further back than the back surface 93a of the rubber stopper 91 to capture an image of the back surface 93a of the rubber stopper 91. Furthermore, as in the second image 81 of FIG. 2B, the camera 11 sets the second focal position 81a at the back surface 93a of the rubber stopper 91 to capture an image of the back surface 93a of the rubber stopper 91. In this way, by setting the focal position of the camera 11 to two (multiple) focal positions, the first focal position 80a and the second focal position 81a, the camera 11 can capture an image of the back surface 93A of the rubber stopper 91, which is located deep within, with increased resolution.

As shown in FIG. 1, the holding device 12 mainly comprises a gripping unit 13, an arm 14, and a drive unit 15. The gripping unit 13 grips the rubber stopper 91 attached to the container 90. The gripping unit 13 is provided at the tip of the arm 14 and grips the main body 92 of the rubber stopper 91. The arm 14 is an arm for moving and rotating the gripping unit 13. When the arm 14 moves or rotates the gripping unit 13 while gripping the rubber stopper 91 with the gripping unit 13, the container 90 to which the rubber stopper 91 is attached moves or rotates. The drive unit 15 comprises a motor (not shown). The drive unit 15 operates the arm 14 by driving the motor. The drive unit 15 is connected to the control device 20. The drive unit 15 drives the motor in response to a signal from the control device 20.

In the detection device 10, the camera 11 is fixed at a predetermined position on the detection device 10, so the holding device 12 moves the container 90 based on the fixed camera 11, thereby setting the imaging position of the camera 11 on the rubber stopper 91.

Specifically, as shown in FIG. 3, the holding device 12 (see FIG. 1) moves the container 90 to a first position P1, thereby setting the imaging position of the camera 11 relative to the rubber stopper 91 as a first imaging position T1 for imaging the back surface 93A of the rubber stopper 91. Here, the first position P1 is the position at which the holding device 12 holds the container 90 so that the camera 11 can image the back surface 93A of the rubber stopper 91 as the focal position.

The holding device 12 (see Figure 1) holds the container 90 so that the axis S of the container 90 is vertical, and moves the container 90 to a first position P1. By the holding device 12 moving the container 90 to the first position P1 in this manner, the first imaging position T1 of the camera 11 is formed on the bottom 90b side of the container 90, in a direction that forms a predetermined angle θ1 with respect to the axis S (vertical direction) of the container 90. In other words, the first imaging position T1 of the camera 11 is formed diagonally below the container 90, whose axis S is vertical.

Here, the predetermined angle θ1 is the angle of the optical axis K of the camera 11 relative to the axis S of the container 90. The predetermined angle θ1 is set at an angle that can be formed so that the optical axis K of the camera 11 is directed toward the back surface 93A of the rubber stopper 91, avoiding the bottom 90b of the container 90 (the lowest position of the container 90 in the vertical direction).

In this way, the first imaging position T1 of the camera 11 is formed diagonally below the container 90 held by the holding device 12. Therefore, even if a drug such as a lyophilized agent settles to the bottom 90b of the container 90, the camera 11 can capture an image of the back surface 93A of the rubber stopper 91 without being affected by the drug.

Also, as shown in FIG. 4, the holding device 12 (see FIG. 1) moves the container 90 to a second position P2, changing the imaging position of the camera 11 relative to the rubber stopper 91 to a second imaging position T2 for imaging the side surface 93B of the rubber stopper 91. Here, the second position P2 is a position where the holding device 12 holds the container 90 in an inclined state so that the camera 11 can image the side surface 93B of the rubber stopper 91 as the focal position.

The holding device 12 moves the container 90 to the second position P2 while holding the container 90 at an angle so that the axis S of the container 90 is perpendicular to the optical axis K of the camera 11. By the holding device 12 moving the container 90 to the second position P2 in this manner, the imaging direction of the camera 11 at the second imaging position T2 is formed in a direction perpendicular to the axis S of the container 90. In other words, the second imaging position T2 of the camera 11 is formed to the side of the container 90, which is tilted so as to be perpendicular to the optical axis K of the camera 11.

Furthermore, the holding device 12 rotates the container 90 around the axis S while gripping the rubber stopper 91 with the gripping portion 13 at the first position P1 and the second position P2, thereby changing the phase of the container 90 relative to the camera 11. In other words, by the holding device 12 rotating the container 90 around the axis S at the first position P1 and the second position P2, the camera 11 captures images of the rubber stopper 91 in multiple phases, i.e., at multiple positions along the circumferential direction of the rubber stopper 91.

Here, because the camera 11 captures an image of the rubber stopper 91 attached to the cylindrical container 90, it may not be possible to capture a clear image of the rubber stopper 91 if light reflected from curved portions of the container 90, for example, enters the imaging area. As a result, it may not be possible to identify foreign matter G from the image of the rubber stopper 91 captured by the camera 11. Therefore, the detection device 10 is configured to rotate the container 90 around the axis S to change the phase of the container 90 relative to the camera 11, so that the portions of the container 90 where light is reflected are imaged at a different phase. Therefore, it is possible to capture an image of the entire back surface 93A, including the back surface 93a, and the entire side surface 93B of the rubber stopper 91.

Furthermore, the camera 11 images the back surface 93A of the rubber stopper 91 from diagonally below the cylindrical container 90. As a result, a portion of the back surface 93A of the rubber stopper 91 is shaded by the camera 11 and cannot be imaged (a blind spot for the camera 11). Therefore, the camera 11 cannot image the entire back surface 93A of the rubber stopper 91 with a single imaging process at the first imaging position T1. Therefore, the detection device 10 is configured to rotate the container 90 around the axis S to change the phase of the container 90 relative to the camera 11, thereby enabling the back surface 93A of the rubber stopper 91 to be imaged at multiple phases, i.e., rotation angles. Therefore, even portions that are shaded by the camera 11 and cannot be imaged can be imaged at any of the phases.

Furthermore, camera 11 captures an image of side surface 93B of rubber stopper 91 from one side of cylindrical container 90. Therefore, side surface 93B on the other side of rubber stopper 91 (the side opposite to the camera 11's imaging position) is in shadow of camera 11 and cannot be imaged (a blind spot of camera 11). Therefore, camera 11 cannot image the entire side surface 93B of rubber stopper 91 with a single imaging process at second imaging position T2. Therefore, detection device 10 is configured to rotate container 90 around axis S to change the phase of container 90 relative to camera 11, thereby enabling the side surface 93B of rubber stopper 91 to be imaged at multiple phases. Therefore, even the portion that is in shadow of camera 11 and cannot be imaged can be imaged at any phase.

Specifically, while gripping the rubber stopper 91 with the gripping portion 13, the holding device 12 intermittently rotates the container 90 around the axis S at predetermined angle intervals, thereby intermittently changing the phase of the container 90 relative to the camera 11. For example, the holding device 12 intermittently rotates the container 90 around the axis S by 60 degrees, thereby changing the phase of the container 90 relative to the camera 11 six times. That is, the camera 11 captures images of the back side of the rubber stopper 91 rotating around the axis S of the container 90 at six phases at the first imaging position T1. The camera 11 also captures images of the side surface 93B of the rubber stopper 91 rotating around the axis S of the container 90 at six phases at the second imaging position T2.

As shown in FIG. 1, the control device 20 is connected to the camera 11 and the holding device 12. The control device 20 controls the camera 11 to capture an image of the container 90. The control device 20 controls the holding device 12 to change the position and rotate the container 90. The control device 20 is mainly composed of a control unit 21, a memory unit 23, and a display unit 24.

The control unit 21 is a CPU (Central Processing Unit) or MPU (Micro-processing Unit), and executes various processes in the detection device 10 according to programs stored in the memory unit 23. The control unit 21 includes a detection unit 22 that detects foreign matter G adhering to the rubber stopper 91 based on an image of the rubber stopper 91 captured by the camera 11.

The detection unit 22 detects foreign matter G adhering to the back surface 93A of the rubber stopper 91 based on an image of the back surface 93A, including the back surface 93a, of the rubber stopper 91 captured by the camera 11. The detection unit 22 detects foreign matter G adhering to the side surface 93B of the rubber stopper 91 based on an image of the side surface 93B of the rubber stopper 91 captured by the camera 11.

The storage unit 23 is a flash memory, RAM (Random Access Memory), or the like, and stores programs executed by the control unit 21 and data generated by the execution of programs by the control unit 21.

The display unit 24 displays various information in the detection device 10. The display unit 24 is composed of, for example, a monitor, a touch panel, etc.

Next, we will explain how the detection device 10 detects foreign matter G adhering to the rubber stopper 91.

The detection device 10 detects foreign matter G adhering to the back surface 93A of the rubber stopper 91 and foreign matter G adhering to the side surface 93B of the rubber stopper 91 in different processes. First, we will explain how the detection device 10 detects foreign matter G adhering to the back surface 93a of the rubber stopper 91.

As shown in FIG. 5, the holding device 12 moves the container 90 to the first position P1 shown in FIG. 3 (S1). At this time, the holding device 12 holds the container 90 so that the axis S of the container 90 is vertical. As a result, the shooting position (first imaging position T1) of the camera 11 is formed on the bottom 90b side of the container 90, in a direction that forms a predetermined angle θ1 with the axis S of the container 90 (vertical direction).

When the container 90 is moved to the first position P1 (S1), the camera 11 sets a focal position (first focal position 80a (see FIG. 2A)) on the back surface 93A of the rubber stopper 91, further back than the back surface 93a (S2). After setting the focal position (S2), the camera 11 captures an image of the back surface 93A of the rubber stopper 91 (S3).

When the camera 11 captures an image of the back surface 93A of the rubber stopper 91 (S3), the holding device 12 rotates the container 90 by a predetermined angle (e.g., 60 degrees) around the axis S of the container 90 (S4). Once the container 90 has been rotated by the predetermined angle (S4), the camera 11 further captures an image of the back surface 93A of the rubber stopper 91 (S5). Once the camera 11 captures an image of the back surface 93A of the rubber stopper 91 (S5), the control unit 21 determines whether the holding device 12 has rotated the container 90 once (S6). If the control unit 21 determines that the container 90 has not rotated once (S6-No), the holding device 12 further rotates the container 90 around the axis S by a predetermined angle (S4). The camera 11 then further captures an image of the back surface 93A of the rubber stopper 91 (S5). That is, the rotation of the container 90 by the holding device 12 (S4) and the image capture of the back surface 93A of the rubber stopper 91 by the camera 11 (S5) are alternately repeated until the holding device 12 rotates the container 90 once.

When the control unit 21 determines that the container 90 has rotated once (S6-Yes), the camera 11 sets the focal position (second focal position 81a (see Figure 2B)) on the near side of the back surface 93A of the rubber stopper 91, for example, on the back surface 93a (S7). After setting the focal position (S7), the camera 11 captures an image of the back surface 93a of the rubber stopper 91 (S8).

When the camera 11 captures an image of the back surface 93a of the rubber stopper 91 (S8), the holding device 12 rotates the container 90 by a predetermined angle around the axis S (S9). Once the container 90 has been rotated by the predetermined angle (S9), the camera 11 further captures an image of the back surface 93a of the rubber stopper 91 (S10). Once the camera 11 captures an image of the back surface 93a of the rubber stopper 91 (S10), the control unit 21 determines whether the holding device 12 has rotated the container 90 once (S11). If the control unit 21 determines that the container 90 has not rotated once (S11-No), the holding device 12 further rotates the container 90 by a predetermined angle around the axis S (S9). The camera 11 then captures an image of the back surface 93a of the rubber stopper 91 (S10). That is, the rotation of the container 90 by the holding device 12 (S9) and the image capture of the back surface 93a of the rubber stopper 91 by the camera 11 (S10) are alternately repeated until the holding device 12 rotates the container 90 once (imaging process).

When the control unit 21 determines that the container 90 has rotated once (S11-Yes), the detection unit 22 determines whether or not a foreign object G is present in the image of the back surface 93a of the rubber stopper 91 captured by the camera 11 (S12, foreign object detection process). That is, the detection unit 22 detects whether or not a foreign object G is attached to the back surface 93a of the rubber stopper 91 based on the image of the back surface 93a of the rubber stopper 91 captured by the camera 11.

When the detection unit 22 determines that a foreign object G is present in the image of the back surface 93a of the rubber stopper 91 captured by the camera 11 (S12-Yes), it determines that a foreign object G is attached to the back surface 93a of the rubber stopper 91 (S13). On the other hand, when the detection unit 22 determines that a foreign object G is not present in the image of the back surface 93a of the rubber stopper 91 captured by the camera 11 (S12-No), it determines that a foreign object G is not attached to the back surface 93a of the rubber stopper 91 (S13).

Next, we will explain how the detection device 10 detects foreign matter G adhering to the side surface 93B of the rubber stopper 91.

As shown in FIG. 6, the holding device 12 moves the container 90 to the second position P2 (S21). At this time, as shown in FIG. 4, the holding device 12 holds the container 90 so that the axis S of the container 90 is perpendicular to the optical axis K of the camera 11. As a result, the shooting position of the camera 11 (second shooting position T2) is formed on the side of the container 90, which is tilted so as to be perpendicular to the optical axis K of the camera 11.

When the container 90 is moved to the second position P2 (S21), the camera 11 captures an image of the side surface 93B of the rubber stopper 91 (S22). When the camera 11 captures an image of the side surface 93b of the rubber stopper 91 (S22), the holding device 12 rotates the container 90 by a predetermined angle (e.g., 60 degrees) around the axis S (S23). When the container 90 is rotated by the predetermined angle (S23), the camera 11 further captures an image of the side surface 93B of the rubber stopper 91 (S24).

When the camera 11 captures an image of the side surface 93B of the rubber stopper 91 (S24), the control unit 21 determines whether the holding device 12 has rotated the container 90 once (S25). If the control unit 21 determines that the container 90 has not rotated once (S25-No), the holding device 12 further rotates the container 90 a predetermined angle around the axis S (S23). The camera 11 then further captures an image of the side surface 93B of the rubber stopper 91 (S24). In other words, the rotation of the container 90 by the holding device 12 (S23) and the image of the side surface 93B of the rubber stopper 91 by the camera 11 (S24) are alternately repeated until the holding device 12 rotates the container 90 once.

When the control unit 21 determines that the container 90 has rotated once (S25-Yes), the detection unit 22 determines whether or not a foreign object G is present in the image of the side surface 93B of the rubber stopper 91 captured by the camera 11 (S26). That is, the detection unit 22 detects whether or not a foreign object G is attached to the side surface 93B of the rubber stopper 91 based on the image of the side surface 93B of the rubber stopper 91 captured by the camera 11.

When the detection unit 22 determines that a foreign object G is present in the image of the side surface 93B of the rubber stopper 91 captured by the camera 11 (S26-Yes), it determines that a foreign object G is attached to the side surface 93B of the rubber stopper 91 (S27). On the other hand, when the detection unit 22 determines that a foreign object G is not present in the image of the side surface 93B of the rubber stopper 91 captured by the camera 11 (S26-No), it determines that a foreign object G is not attached to the side surface 93B of the rubber stopper 91 (S28).

As described above, according to this embodiment, as shown in FIG. 3 , images of the back surface 93a of the rubber stopper 91 are captured from multiple first imaging positions T1 formed on the bottom 90b side of the container 90 in a direction that forms a predetermined angle θ1 with respect to the axis S of the container 90. Therefore, the back surface 93A of the rubber stopper 91 can be imaged using light rays along an optical axis that passes through the side of the container 90 without passing through the bottom 90b of the container 90. Therefore, even if a drug such as a lyophilized drug settles on the bottom 90b of the container 90, an image of the back surface 93A of the rubber stopper 91 can be captured while avoiding the drug. Therefore, foreign matter adhering to the back surface 93A of the rubber stopper 91 can be accurately detected from the image of the back surface 93A of the rubber stopper 91 captured by the camera 11, without being affected by the drug inside the container 90.

In addition, according to this embodiment, images of the back surface 93A of the rubber stopper 91 are captured at multiple focal positions (first focal position 80a, second focal position 81a) from the first imaging position T1. Therefore, even when detecting foreign matter G in a rubber stopper 91 with depth in the back surface 93A, the camera 11 can capture images of the finer details of the back surface 93A of the rubber stopper 91 at multiple focal positions (first focal position 80a, second focal position 81a). Therefore, regardless of the shape of the back surface 93A of the rubber stopper 91, foreign matter G adhering to the back surface 93A of the rubber stopper 91 can be accurately detected from the images of the back surface 93A of the rubber stopper 91 captured by the camera 11.

As shown in Figures 3 and 4, the camera 11 captures an image of a rubber stopper 91 attached to a cylindrical container 90. If light reflected from a curved portion of the container 90 or the like enters the imaging area, it may not be possible to capture a clear image of the rubber stopper 91. However, in this embodiment, the container 90 is rotated around the axis S to change the phase of the container 90 relative to the camera 11, so that the portion of the container 90 from which light is reflected is imaged at a different phase. Therefore, it is possible to capture an image of the entire back surface 93A, including the back surface 93a, of the rubber stopper 91, as well as the entire side surface 93B.

As shown in Figure 3, when detecting foreign matter G attached to the back surface 93A of the rubber stopper 91 attached to the top opening of the container 90 by imaging the back surface 93A on the inside of the container 90 from diagonally below the container 90, there is a possibility that a shadowed portion will occur on the back surface 93A. However, in this embodiment, the container 90 is rotated around the axis S to change the phase of the container 90 relative to the camera 11, so that the shadowed portion can be imaged at any phase. As a result, the entire back surface 93A of the rubber stopper 91 can be evenly imaged, making it possible to detect the presence of foreign matter G.

As shown in Figure 4, when imaging the side surface 91c of the rubber stopper 91 from the side of the container 90, the portion of the rubber stopper 91 opposite the imaging side in the circumferential direction is in shadow and cannot be imaged. However, in this embodiment, the container 90 is rotated around the axis S to change the phase of the container 90 relative to the camera 11, so that the portion that would be in shadow can be imaged in either phase. As a result, the entire circumference of the side surface 91c of the rubber stopper 91 can be evenly imaged, making it possible to detect the presence of foreign matter G.

In this embodiment, the back surface 93A of the rubber stopper 91 is imaged while the container 90 is held so that the axis S is vertical, but this is not limited to this. As long as the optical axis K of the camera 11 can be set to avoid the lowest vertical position of the container 90, the back surface 93A of the rubber stopper 91 may be imaged while the container 90 is held so that the axis S is at a predetermined angle to the vertical.

In this embodiment, the container 90 is rotated around the axis S to change the phase of the container 90 relative to the camera 11, thereby enabling the entire back surface 93A and side surface 93B of the rubber stopper 91 to be captured evenly, but this is not limited to this. For example, the first imaging position T1 and second imaging position T2 of the camera 11 may be changed by rotating the camera 11 around the axis S of the container 90.

In this embodiment, the focal positions of the camera 11 relative to the back surface 93a of the rubber stopper 91 are set in the order from the rear side relative to the back surface 93a of the rubber stopper 91 (first focal position 80a) to the front side relative to the back surface 93a of the rubber stopper 91 (second focal position 81a). However, this is not limited to this, and the focal positions may be set in the order from the front side relative to the back surface 93a of the rubber stopper 91 (second focal position 81a) to the rear side relative to the back surface 93a of the rubber stopper 91 (first focal position 80a).

In this embodiment, the container 90 is rotated around the axis S in 60-degree increments to capture images, but this is not limited to this. For example, the container 90 may be rotated in 45-degree increments to capture images, or may be rotated at any combination of angles to capture images.

10 Detector 11 Camera (imaging unit)
22 Detection unit 80 First image (image)
80a First focal position (focal position)
81 Second image (image)
81b Second focal position (focal position)
90 Container 90b Bottom of container 91 Rubber stopper (stopper member)
93A Back surface of rubber stopper 93a Back surface of rubber stopper 93B Side surface of rubber stopper G Foreign matter S Axis center of container T1 First imaging position T2 Second imaging position

Claims (4)

A foreign matter detection device for detecting foreign matter adhering to a plug member attached to a translucent container,
an imaging unit that images the plug member;
a detection unit that detects foreign matter adhering to the plug member based on an image of the plug member captured by the imaging unit;
Equipped with
the imaging unit images a back surface of the plug member facing the inside of the container at a plurality of focal positions along a depth direction of the back surface at a plurality of first imaging positions formed on the bottom side of the container in a direction forming a predetermined angle with respect to an axis of the container,
the detection unit detects foreign matter adhering to the back surface of the plug member based on a plurality of images of the back surface of the plug member captured by the imaging unit from the first imaging position ;
the plurality of focal positions include at least a focal position on a near side relative to the back surface of the back surface portion of the plug member and a focal position on a far side relative to the back surface of the back surface portion of the plug member,
A foreign object detection device , wherein a depth between a front side and a back side of the rear surface portion of the plug member relative to the rear surface is greater than a depth of field of the imaging unit . 2. The foreign object detecting device according to claim 1, wherein the imaging unit captures images of the plug member attached to the container when the container is rotated to a plurality of angular positions around an axis. the imaging unit images the side surface of the plug member attached to the container at a plurality of second imaging positions formed in a direction forming a predetermined angle with respect to an axis of the container,
3. The foreign object detection device according to claim 1, wherein the detection unit detects foreign objects adhering to the side surface of the plug member based on a plurality of images of the side surface of the plug member captured by the imaging unit from the plurality of second imaging positions. A foreign matter detection method for detecting foreign matter adhering to a plug member attached to a translucent container, comprising:
an imaging step of imaging a back surface of the plug member facing the inside of the container at a plurality of focal positions along a depth direction of the back surface at a plurality of first imaging positions formed on the bottom side of the container in a direction forming a predetermined angle with respect to the axis of the container;
a foreign matter detection step of detecting foreign matter adhering to the back surface of the plug member based on a plurality of images of the back surface of the plug member captured at the first imaging position in the imaging step;
Including,
the plurality of focal positions include at least a focal position on a near side relative to the back surface of the back surface portion of the plug member and a focal position on a far side relative to the back surface of the back surface portion of the plug member,
a depth between a front side and a back side of the rear surface portion of the plug member relative to the rear surface is greater than a depth of field of imaging in the imaging step .