Apparatus and method for inspecting transparent cylindrical containers containing a milky product, particularly for medical applications

Abstract

The invention relates to an apparatus for inspecting a transparent cylindrical container, comprising: a support and / or gripping device for the cylindrical container, adapted to support the cylindrical container and to rotate it about a vertical rotation axis; a video camera, directed to frame and capture a pixel image of a window of the lateral wall of the cylindrical container; a first collimated lighting device, oriented to illuminate said window; a second lighting device, collimated and oriented to illuminate said window in opposition to said first lighting device in a symmetrical position with respect to said window; a control unit, operatively connected to the support and / or gripping device, to the video camera and to the first and second lighting devices and programmed to: capture images of said window at constant angular intervals, alternately activating the first and second lighting devices for each angular range until the cylindrical container is completely rotated 360°, process the images obtained in order to register the internal or external position of any contaminant with respect to the lateral wall of the cylindrical container.

Description

Technical Field

[0001] This invention relates to an apparatus and method for examining a transparent cylindrical container containing emulsions, particularly for medical applications. Background Technology

[0002] As is well known in the medical field, it is essential to analyze the transparent containers of medical substances to detect the presence of any impurities within them. In the event of a positive result, the container must obviously be discarded, as any type of contamination in the medical substance is unacceptable.

[0003] The systems used in this field are optical systems that utilize cameras to scan each container to detect any contaminants. However, known systems have some drawbacks.

[0004] In reality, while known optical systems can detect the presence of contaminants / impurities, they cannot reliably distinguish whether the contaminant is located inside or outside the container. Therefore, it is clear that the container should only be discarded if the contaminant is inside, i.e., in contact with the medical material contained therein.

[0005] For safety reasons, the calibration of known systems is obviously more "conservative," resulting in a higher positive scrap rate. To at least partially compensate for this deficiency, the inspection time for containers could be extended. However, this approach, while aiming to reduce erroneous scrap, would unacceptably extend inspection time and increase costs.

[0006] It should be remembered that inspection time is a cost factor that cannot be ignored, as the batch to be inspected may contain tens of thousands of containers.

[0007] Therefore, known solutions do not allow for the simultaneous achievement of a low positive scrap rate and a short inspection time. Summary of the Invention

[0008] In view of this, it is necessary to address the defects and limitations existing in the above-mentioned prior art.

[0009] To achieve the above objectives, the present invention relates to an apparatus, particularly for medical applications, for examining a transparent cylindrical container containing a milky product, comprising: a support and / or clamping device for the cylindrical container, adapted to support the cylindrical container and provided with a mechanism for rotating it about a vertical axis of rotation, the vertical axis of rotation coinciding with the cylindrical axis of symmetry of the cylindrical container; a camera, guided to frame and capture pixel-like images of a window on the side wall of the cylindrical container; a collimating first illumination device, guided to illuminate the window; a second illumination device, collimated and oriented to illuminate the window symmetrically opposite the first illumination device about the window; and a control unit, operatively connected to the support and / or clamping device, the camera, and the first and second illumination devices and programmed to: A first and second partial image of the capture window are captured at a constant angular spacing. The first and second illumination devices are alternately activated for each angular spacing until the cylindrical container is completely rotated 360°. The first and second partial images obtained by alternately activating the first illumination device to obtain a first aggregated image of the cylindrical container and activating the second illumination device to obtain a second aggregated image of the cylindrical container are continuously correlated. The presence of potentially irregular pixels with color differences corresponding to contaminants is identified within each aggregated image. If at least one irregular pixel is identified, a control image is derived based on the difference between the first and second aggregated images, and the position of the contaminant relative to the sidewall of the cylindrical container is recorded based on the control image.

[0010] The present invention also relates to a method, particularly for medical applications, for examining a transparent cylindrical container containing an emulsion, comprising the steps of: providing a transparent cylindrical container containing the emulsion, supported for rotation about a vertical axis of rotation coinciding with the axis of symmetry of the container itself; providing a camera, guided to frame and capture pixel-wise images of a window on the sidewall of the cylindrical container; providing a collimating first illumination device, guided to illuminate the window; providing a second illumination device, collimated and oriented to illuminate the window opposite the first illumination device at a symmetrical position about the window; and capturing a first partial image and a second partial image of the window at a constant angular spacing, for each angle... The first and second lighting devices are alternately activated until the cylindrical container is fully rotated 360°; the individual local images obtained by alternately activating the first lighting device to obtain a first aggregated image of the cylindrical container and activating the second lighting device to obtain a second aggregated image of the cylindrical container are continuously correlated; the presence of potentially irregular pixels with color differences corresponding to contaminants is identified within each aggregated image; if at least one irregular pixel is identified, a control image is derived based on the difference between the first and second aggregated images, and the position of the contaminant relative to the sidewall of the cylindrical container is recorded based on the control image. Attached Figure Description

[0011] Further features and advantages of the invention will become clearer from the following description of preferred, non-limiting embodiments, as shown in the figures:

[0012] Figures 1a to 1b and Figures 2a to 2b A top view schematic diagram depicting an apparatus for inspecting a transparent cylindrical container containing an emulsion product according to an embodiment of the present invention;

[0013] Figure 3a A top view schematic diagram of the inspection device according to the present invention during the continuous inspection phase is shown;

[0014] Figure 3b Depicting succession Figure 3a An unfolded view of the side surface image of the container obtained after the corresponding inspection stage;

[0015] Figures 4a to 4d A schematic diagram illustrating the processing of images captured by the detection device according to the present invention is provided.

[0016] Figure 5 A detailed diagram depicting the identification of external contaminants in a container analyzed according to the apparatus and inspection method of the present invention;

[0017] Figure 6 A detailed diagram depicting the identification of internal contaminants in a container analyzed by the apparatus and inspection method according to the present invention.

[0018] Common elements or element portions in the embodiments described below will be labeled with the same reference numerals. Detailed Implementation

[0019] Referring to the accompanying drawings, reference numeral 4 is used to generally indicate an apparatus, particularly for medical applications, for examining a transparent cylindrical container 8 containing an emulsion product.

[0020] It should be noted that the cylindrical container 8 is transparent to allow the substance contained therein to be seen from the outside, preferably an emulsion. It should be noted that a "milk" is a highly turbid solution. Turbidity is the ratio of the intensity of light diffused by the solution in the direction perpendicular to the incident light beam to the intensity of the light beam itself (measured using a turbidimeter). Turbidity can also be defined as related to optical transparency, i.e., the ratio of the intensity of light transmitted in the same direction as the incident light to the intensity of the incident light (measured using a turbidimeter).

[0021] Therefore, the cylindrical container 8 is preferably made of glass or plastic, such as plexiglass.

[0022] Furthermore, the cylindrical containers 8 have an axis of axial symmetry XX; in other words, they are rotating entities about the axis of axial symmetry XX.

[0023] The inspection device 4 includes a support and / or clamping device (not shown) for a cylindrical container 8, which is adapted to support the cylindrical container and is provided with a motor mechanism for rotating it about a vertical rotation axis YY, which coincides with the cylindrical axis of symmetry XX of the cylindrical container 8.

[0024] For the purposes of this invention, multiple support and / or clamping devices can be used for the cylindrical container 8; care must be taken to ensure that the support and / or clamping devices do not obstruct the observation and inspection of any impurities on the cylindrical container 8. For this purpose, support and / or clamping devices that clamp the container via its support base or otherwise pull the container to rotate are preferred. Various clamping devices / methods suitable for the above purposes exist. For example, the bottle bottom cap can be clamped or a clamp can be used at the bottle neck. The key point is that these devices allow the bottle to rotate about its main axis.

[0025] Device 4 also includes a camera 12, which is guided to frame and capture pixel-wise images of the window 16 of the sidewall 20 of the cylindrical container 8. Clearly, since the cylindrical container 8 is transparent, the camera 12 can capture images not only of the sidewall 20 of the cylindrical container 8 but also of its contents (preferably a milky liquid). In fact, the purpose of this invention is to detect the presence of impurities and then distinguish whether these possible impurities are on the outside (i.e., on the outer surface 22 of the sidewall 20) or on the inside (i.e., on the inner surface 23 of the sidewall 20 of the cylindrical container 8). If the impurity is on the inner surface 23, the impurity will be in direct contact with the liquid contained in the cylindrical container 8 and needs to be discarded.

[0026] The device 4 also includes a first lighting device 24 collimated and oriented to illuminate the window 16 and a second lighting device 28 collimated and oriented to illuminate the window 16.

[0027] The second lighting device 28 is positioned symmetrically to the first lighting device 24 about the window 16.

[0028] Device 4 also includes a control unit 32, operably connected to the support and / or clamping device, camera 12, and the first lighting device 24 and the second lighting device 28, and programmed to: capture a first partial image 36' and a second partial image 36" of the window 16 at a constant angular interval, alternately activating the first lighting device 24 and the second lighting device 28 for each angular interval until the cylindrical container has rotated a full 360°. Figures 3a to 3b Specifically, camera 12 captures a first partial image 36' during the activation of the first lighting device 24 and a second partial image 36' during the activation of the second lighting device 28.

[0029] Therefore, the control unit 32 is programmed to continuously associate the various partial images 36', 36'' obtained by alternately activating the first lighting device 24 to obtain the first aggregated image 40' of the cylindrical container 8 and activating the second lighting device 28 to obtain the second aggregated image 40' of the cylindrical container 8. Figures 4c to 4d ).

[0030] Therefore, the control unit performs the following steps: identifying the presence of any irregular pixel 48 within each aggregated image, the irregular pixel 48 having a color difference corresponding to the contaminant.

[0031] If at least one of the irregular pixels 48 is identified, a control image 52 is derived based on the difference between the first aggregated image 40' and the second aggregated image 40', and the position of the contaminant relative to the sidewall 20 of the cylindrical container 8 is recorded based on the control image 52.

[0032] Specifically, in order to identify the location, according to a feasible embodiment, the control unit 32 is programmed to: if the control image 52 includes at least one irregular pixel 48 ( Figure 5 If the contaminant is located outside the side wall 20 of the cylindrical container 8, then the control image 52 is classified as being outside the side wall 20 of the cylindrical container 8 if it does not include at least one irregular pixel 48. Figure 6 If the pollutant is located inside the side wall 20 of the cylindrical container 8, then the pollutant will be classified as being inside the side wall 20 of the cylindrical container 8.

[0033] Obviously, if the contaminants are classified as being inside the cylindrical container 8, the container will be discarded.

[0034] It is understandable that in order to accurately detect and classify pollutants, it is necessary to precisely photograph window 16 by alternately activating the first lighting device 24 and the second lighting device 28.

[0035] Therefore, according to one feasible embodiment, the support and / or clamping device is provided with a rotary encoder to measure the rotation of the cylindrical container 8; preferably, the rotary encoder is operatively connected to the control unit 32 to alternately activate the first lighting device 24 and the second lighting device 28.

[0036] The angular spacing of the linear camera scanning container 8 depends on the resolution desired to be applied in the extension direction of the container. These angular ranges can be, for example, 0.044 degrees, which is obtained by dividing the 360° rotation of the container by 8192 encoder pulses (360° / 8192).

[0037] Regular angular spacing is, for example, angular spacing of 0.05 degrees (sexagenary).

[0038] According to one feasible embodiment, in order to avoid resolution loss, the image acquisition of the sidewall 20 of the cylindrical container 8, especially its window 16, is doubled (2 times) oversampled, so that the resolution in the lateral extension direction is doubled, thus obtaining two final images with the correct resolution.

[0039] The operation of the inspection device according to the present invention will now be described.

[0040] Specifically, the basic principle of the present invention begins with the assumption that contaminants attached to the outer surface 22 of the sidewall 20, when irradiated by collimated, non-orthogonal incident light, will cast a shadow on the emulsion liquid, wherein it is assumed that the distance of the light to the liquid is equal to the thickness of the (transparent) sidewall of the container 8. Figures 1a to 1b On the other hand, objects or contaminants adhering to the inner surface 23 of the cylindrical container 8 will come into contact with the liquid, thus structurally preventing any shadows from being cast on the liquid in direct contact with it. Figures 2a to 2b ).

[0041] Detecting the projected shadow of a contaminant can determine whether the contaminant is inside or outside the cylindrical container 8. Therefore, the problem shifts from identifying a thin layer of contaminant to identifying the object's shadow. To this end, stereo lighting is introduced into the method.

[0042] When an object on the outer surface 22 of the cylindrical container 8 is illuminated by two collimating illuminators (i.e., the first illuminator 24 and the second illuminator 28), its light cuts into the outer surface 22 at a symmetrical angle, casting two symmetrically opposite shadows.

[0043] During the rotation of cylindrical container 8 ( Figures 3a to 3b The camera 12 captures multiple lines, for example, by using a rotary encoder at a constant angular spacing Δθ, which is connected to a motor that causes the cylindrical container 8 to rotate. In this way, the camera 12 will produce a continuous extension of the side surface 20 of the cylindrical container 8.

[0044] During row acquisition, the symmetrical first illumination device 24 and second illumination device 28 are activated in an alternating mode. Then, during the acquisition of even-numbered rows, only the first illumination device 24 is activated while the second illumination device 28 remains off. The sum of these even-numbered rows, i.e., the sum of the first partial images 36' captured during the activation of the first illumination device 24, constitutes the first aggregated image 40'. Figures 4a to 4d ).

[0045] The first aggregated image 40' will be an extension of the entire sidewall 20 of the cylindrical container 8 obtained by activating only the first lighting device 24.

[0046] Symmetrically, during the acquisition of odd-numbered rows, only the second lighting device 28 is activated while the first lighting device 24 remains off.

[0047] The sum of the odd-numbered rows, that is, the sum of the second partial images 36” captured during the activation of the second lighting device 28, constitutes the second aggregated image 40”. Figures 4a to 4d ).

[0048] The first aggregated image 40” will be an extension of the entire sidewall 20 of the cylindrical container 8 obtained by activating only the first lighting device 28.

[0049] The number of rows in the first aggregated image 40' and the second aggregated image 40" will be half the number of rows in the overall captured image.

[0050] As shown in the figure, in order to avoid the impact of resolution loss, the captured image will be doubled oversampled, thus doubling the resolution in the extension direction of the sidewall 20. This will result in two final images with the correct resolution.

[0051] At this point, the so-called control image 52 is calculated as the difference between the first aggregated image 40' and the second aggregated image 40'", highlighting only the irregular pixels 48, i.e., pixels where the grayscale changes. This is simply due to the presence of shadows at different points in the first aggregated image 40' relative to the second aggregated image 40'. Contaminants (if present) will not appear in different locations; only their shadows will change. Therefore, it should be understood that, in the presence of the difference, the object generating this difference will be located on the outside and between the two shadows ( Figure 5 The object will also be positioned at a precise distance from these two shadows, proportional to the thickness of the sidewall 20 of the cylindrical container 8 and the angle of incident light. The object will ultimately be excluded from the contaminants inside the bottle.

[0052] As can be seen from the above, the equipment and inspection method according to the present invention can overcome the defects existing in the prior art.

[0053] In particular, the present invention is able to detect contaminants present inside the container (which are unacceptable for testing purposes) and distinguish them from contaminants present outside the container (which are instead considered acceptable).

[0054] This implies a significant reduction in false positive scrap rates caused by detecting dirt, fibers, and other objects outside the container that are not in contact with the medicine.

[0055] The "spin & stop" method is typical for particle analysis of transparent, aqueous products. This method is unsuitable because centrifugation is not allowed, and contaminants must be held to the outer wall. If contaminants migrate away from the wall, even by only a few tenths of a millimeter, they will be invisible. Visual methods (i.e., through continuous rotation and rotating image acquisition) can detect the contaminants present.

[0056] This process can distinguish between external and internal locations of contaminants, allowing for the use of visual methods to analyze containers containing emulsions, thereby significantly reducing false rejection rates caused by external contamination.

[0057] Those skilled in the art may make various modifications and alterations to the above-described equipment and inspection methods to meet occasional specific needs, but all of these are within the scope of the invention as defined in the appended claims.

Claims

1. A device (4) for examining a transparent cylindrical container (8) containing an emulsion product for medical applications, comprising: - A support and / or clamping device for a cylindrical container (8), adapted to support the cylindrical container (8) and provided with a mechanism for rotating it about a vertical axis of rotation, the vertical axis of rotation coinciding with the cylindrical axis of symmetry of the cylindrical container (8); - Camera (12), guided to frame and capture pixel-like images of the window (16) of the side wall (20) of the cylindrical container (8); - A collimating first lighting device (24) is guided to illuminate the window (16); - A second lighting device (28) is collimated to illuminate the window (16) opposite the first lighting device (24) at a position symmetrical about the window (16). - A control unit (32), operably connected to the support and / or clamping device, the camera (12), and the first lighting device (24) and the second lighting device (28) and programmed to: - Capture a first partial image (36') and a second partial image (36'') of the window (16) at a constant angular spacing, and alternately activate the first lighting device (24) and the second lighting device (28) for each angular spacing until the cylindrical container (8) has rotated 360° completely. - The first partial image (36') and the second partial image (36'') are obtained by continuously linking the first aggregated image (40') of the cylindrical container (8) obtained by alternately activating the first lighting device (24) and activating the second lighting device (28) to obtain the second aggregated image (40'') of the cylindrical container (8). - Identify the presence of potentially irregular pixels (48) within each aggregated image (40', 40''), said irregular pixels (48) having color differences corresponding to contaminants, - In the case of identifying at least one of the irregular pixels (48), a control image (52) is derived based on the difference between the first aggregated image (40') and the second aggregated image (40''), and the position of the contaminant relative to the sidewall (20) of the cylindrical container (8) is recorded based on the control image (52).

2. The device (4) according to claim 1, wherein, The control unit (32) is programmed as follows: - If the control image (52) includes at least one irregular pixel (48), the contaminant is classified as being outside the sidewall (20) of the cylindrical container (8). - If the control image (52) does not include at least one irregular pixel (48), the contaminant is classified as being inside the sidewall (20) of the cylindrical container (8).

3. The device (4) according to claim 1 or 2, wherein, The support and / or clamping device is provided with a rotary encoder to measure the rotation of the cylindrical container (8), the rotary encoder being operatively connected to the control unit (32) to alternately activate the first lighting device (24) and the second lighting device (28).

4. The device (4) according to claim 1 or 2, wherein, In order to avoid loss of resolution, the image acquisition of the sidewall (20) of the cylindrical container (8) is doubled by oversampling, thereby doubling the resolution in the surface extension direction.

5. The device (4) according to claim 1 or 2, wherein, The constant angular spacing is 0.05 degrees.

6. A method for examining a transparent cylindrical container (8) containing an emulsion product for medical applications, comprising the following steps: - Provides a transparent cylindrical container (8) containing an emulsion product, which supports rotation about a vertical axis of rotation that coincides with the axis of symmetry of the container (8) itself; - Provide a camera (12) to frame and capture pixel-like images of the window (16) of the sidewall (20) of the cylindrical container (8); - Provides a collimating first lighting device (24) to guide the illumination of the window (16); - Provide a second lighting device (28) collimated to illuminate the window (16) opposite the first lighting device (24) at a position symmetrical about the window (16); - Capture a first partial image (36') and a second partial image (36'') of the window (16) at a constant angular spacing, and alternately activate the first lighting device (24) and the second lighting device (28) for each angular spacing until the cylindrical container (8) is completely rotated 360°; - The individual partial images (36', 36'') are continuously associated by alternately activating the first lighting device (24) to obtain a first aggregated image (40') of the cylindrical container (8) and activating the second lighting device (28) to obtain a second aggregated image (40'') of the cylindrical container (8); - Identify the presence of potentially irregular pixels (48) within each aggregated image (40', 40''), the irregular pixels (48) having a color difference corresponding to the contaminant; - In the case of identifying at least one of the irregular pixels (48), a control image (52) is derived based on the difference between the first aggregated image (40') and the second aggregated image (40''), and the position of the contaminant relative to the sidewall (20) of the cylindrical container (8) is recorded based on the control image (52).

7. The method according to claim 6, comprising the following steps: - If the control image (52) includes at least one irregular pixel (48), the contaminant is classified as being outside the sidewall (20) of the cylindrical container (8); - If the control image (52) does not include irregular pixels (48), the contaminant is classified as being inside the sidewall (20) of the cylindrical container (8).

8. The method according to claim 6 or 7, comprising the following steps: Double oversampling of the image acquisition of the sidewall (20) of the cylindrical container (8) doubles the resolution in the surface extension direction.

9. The method according to claim 6 or 7, wherein, The constant angular spacing is 0.05 degrees.

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