Imaging device and method for detecting seams between individual packaging bags

Abstract

To provide an imaging device for a drug packaging machine. [Solution] The imaging device (100) of the drug packaging machine (300) comprises a first polarizer (101) and a second polarizer (102) between which a strip (200) of packaging bags can be positioned, a camera (103) for imaging a first surface of the strip (200) of packaging bags through the second polarizer (102), and means (104) for changing the polarization direction of the first polarizer (101) or the second polarizer (102). Furthermore, the present invention relates to a method for detecting a seam portion (203) between packaging bags (201, 202).

Description

Technical Field

[0001] The present invention relates to an imaging device and method for detecting a seam portion between sub-packaging bags according to the preamble of the appended independent claims. Furthermore, the present invention relates to a pharmaceutical sub-packaging machine.

Background Art

[0002] Various pharmaceutical sub-packaging machines for automatically dispensing medications to patients are known. Many such pharmaceutical sub-packaging machines use strips of pre-packaged sub-packaging bags, and each sub-packaging bag contains the medications to be taken by the patient at a determined date and time. The pharmaceutical sub-packaging machine separates the sub-packaging bags from the strip and dispenses them to the patient one by one.

[0003] The sub-packaging bags to be dispensed are separated from the strip of sub-packaging bags using a cutting device. The cutting device generally cuts the strip in a transverse direction at a position determined by an imaging device. The strip of sub-packaging bags should be cut along the seam portion located between the sub-packaging bags.

[0004] A problem associated with known imaging devices is that, in many cases, the position of the seam portion is not accurately detected, and as a result, the strip of sub-packaging bags is cut at an incorrect position. In the worst case, the sub-packaging bag is cut in half, the medications fall out of the sub-packaging bag, and may fall into the pharmaceutical sub-packaging machine.

Summary of the Invention

Problems to be Solved by the Invention

[0005] The main object of the present invention is to reduce and further eliminate the problems of the aforementioned related art.

[0006] An object of the present invention is to provide an imaging device for a pharmaceutical sub-packaging machine. More specifically, an object of the present invention is to provide an imaging device that enables accurate detection of the seam portion between sub-packaging bags.

[0007] Another objective of the present invention is to provide a method that enables accurate detection of seams between individual packaging bags.

[0008] Furthermore, an object of the present invention is to provide a drug packaging machine for dispensing medication to patients. [Means for solving the problem]

[0009] To achieve the above objectives, the imaging apparatus and method according to the present invention are characterized by those shown in the feature portions of the appended independent claims. Advantageous embodiments of the present invention are described in the dependent claims.

[0010] The imaging device according to the present invention comprises a first polarizer and a second polarizer, which can position a strip of a packaging bag between the first polarizer and the second polarizer; a camera for imaging a first surface of the strip of the packaging bag through the second polarizer; and means for changing the polarization direction of the first polarizer or the second polarizer.

[0011] The imaging device according to the present invention can be used in a drug packaging machine for handling strips of drug packaging bags. The strips of drug packaging bags are formed by joining several bags together, with each bag containing medication to be taken by a patient at a predetermined time. A seam separates the bags from the strip, and the strip is cut along this seam to separate the bags. The seam typically includes a heat seal. The separated bags can be dispensed to the patient one bag at a time.

[0012] The first and second polarizers are linear polarizers. A linear polarizer is an optical filter that transmits light waves of a specific polarization and blocks light waves of other polarizations. In other words, a linear polarizer works by transmitting light that vibrates in a specific direction (polarization direction) and absorbing or reflecting light that vibrates in other directions. The first and second polarizers are intended to improve the visibility of the seam (heat seal). The polarization of light in the seam is different from the polarization of other parts. The first and second polarizers are arranged parallel to each other and spaced apart. The distance between the first and second polarizers can be, for example, 10 mm to 150 mm. The strip of the packaging bag to be imaged is positioned between the first and second polarizers such that the first surface of the strip faces the first surface of the second polarizer, and the second surface of the strip faces the first surface of the first polarizer.

[0013] The polarization direction of the first or second polarizer can be changed by means for changing the polarization direction. The polarization direction of the polarizer is electrically or mechanically controllable. The means for changing the polarization direction of the first or second polarizer may include an actuator that rotates the polarizer to mechanically control the polarization direction, or it may include a control unit configured to electrically control the polarization direction by changing the voltage or current supplied to the polarizer.

[0014] The camera is positioned to image the first surface of the packaging strip through a second polarizer. The camera is configured to image the strip using different polarization directions of the first or second polarizer. The imaging device may include means for processing the captured image to detect seam portions between the packaging bags. The processing means may include a processor and a memory containing computer program code, the memory and computer program code configured to process the captured image by the processor to detect seam portions between the packaging bags. Other information, such as characters printed on the packaging bags, may also be recognized from the captured image. The camera is preferably a digital camera. One or more lenses and / or mirrors may be placed in the optical path between the camera and the second polarizer.

[0015] An advantage of the imaging device according to the present invention is that it can accurately detect the seam between individual packaging bags.

[0016] According to one embodiment of the present invention, the means for changing the polarization direction of the first polarizer or the second polarizer is configured to change the polarization direction between a first polarization direction in which the polarization directions of the first polarizer and the second polarizer are perpendicular, and a second polarization direction in which the polarization directions of the first polarizer and the second polarizer are parallel.

[0017] When the polarization directions of the first and second polarizers are perpendicular, the polarizers can block the passage of light from the second face of the first polarizer to the second face of the second polarizer, provided that the polarization state of the light has not changed due to interaction with the strip of the packaging bag. The areas where the polarization has changed will appear bright in the image. When the polarization directions of the first and second polarizers are parallel, the polarizers allow light vibrating in the second polarization direction to pass from the second face of the first polarizer to the second face of the second polarizer. If the polarization state of the light has changed due to interaction with the strip of the packaging bag, these areas will appear dark in the image.

[0018] The camera is preferably configured to capture images of the packaging strip both when the polarization directions of the first and second polarizers are perpendicular and when the polarization directions of the first and second polarizers are parallel. The advantage of this configuration is that it improves the detection accuracy of the seams of the packaging.

[0019] According to one embodiment of the present invention, the imaging device includes a first light source for illuminating a second surface of a strip of packaging bag through a first polarizer. The first light source is positioned on the second surface of the first polarizer. The amount and polarization state of light incident on the camera from the first light source depend not only on the properties of the strip of packaging bag through which the light passes, but also on the polarization directions of the first and second polarizers.

[0020] The first light source is preferably positioned to provide essentially uniform light distribution to the second surface of the strip. The first light source can be a light panel positioned in contact with or spaced apart from the second surface of the first polarizer. The first light source may include one or more LEDs. The LEDs may be arranged together in an LED array or matrix. The imaging device may include a control unit configured to switch the first light source on and off.

[0021] According to one embodiment of the present invention, the imaging device includes a second light source for illuminating a first surface of the strip of the packaging bag. The second light source is preferably located in the space between a first polarizer and a second polarizer. A portion of the light emitted from the second light source is reflected from the first surface of the strip of the packaging bag, passes through the second polarizer, and enters the camera. The amount and polarization state of the light entering the camera from the second light source depend not only on the characteristics of the strip of the packaging bag but also on the polarization direction of the second polarizer.

[0022] The second light source is preferably arranged to provide essentially uniform light distribution to the first surface of the strip. The second light source may include one or more LEDs. The LEDs may be arranged together in an LED array or matrix. The imaging device may include a control unit configured to switch the second light source on and off.

[0023] According to one embodiment of the present invention, the imaging device includes a reflector for reflecting light from a second light source toward a first surface of a strip of a packaging bag, the reflector having an aperture through which the first surface of the strip of the packaging bag can be imaged. The reflector is preferably located in the space between a first polarizer and a second polarizer. The reflector is positioned such that its opening faces the first surface of the first polarizer. The reflector is preferably formed together with the second light source to provide essentially uniform light distribution to the first surface of the strip of the packaging bag. The aperture through which the strip of the packaging bag is imaged faces the first surface of the second polarizer. The shape of the aperture can be, for example, circular or rectangular. The diameter of a circular aperture can be, for example, 5 mm to 30 mm, and the length of each side of a rectangular aperture can be, for example, 5 mm to 30 mm.

[0024] According to one embodiment of the present invention, the reflector is a tunnel-shaped reflector. The strip of the packaging bag can be transported inside the tunnel-shaped reflector.

[0025] According to one embodiment of the present invention, a second light source is mounted in an opening of the reflector. Preferably, the second light source is mounted in an opening of the reflector such that most of the light emitted from the second light source is directed toward the reflective surface of the reflector, and the light is reflected from that reflective surface toward the first surface of the packaging bag strip.

[0026] According to one embodiment of the present invention, the imaging device includes a transparent panel for supporting a strip of sub-packaging bags. The transparent panel is disposed in the space between the first polarizer and the second polarizer and supports the second surface of the strip of sub-packaging bags. The transparent panel can be made of glass or acrylic.

[0027] Furthermore, the present invention relates to a medicine sub-packaging machine for dispensing medicine to a patient. The medicine sub-packaging machine includes at least one imaging device according to the present invention.

[0028] The medicine sub-packaging machine may include a chamber into which a strip of sub-packaging bags can be inserted. The strip of sub-packaging bags is conveyed from the chamber to the outlet of the medicine sub-packaging machine using one or more conveying devices such as a pair of rollers rotated in opposite directions by a motor. The medicine sub-packaging machine separates the sub-packaging bags from the strip and dispenses them to the patient one by one. For this purpose, the medicine sub-packaging machine may include a cutting device configured to separate the sub-packaging bags from the strip of sub-packaging bags by cutting the strip in a transverse direction along the seam portion between the sub-packaging bags. The separated sub-packaging bags can be conveyed to the outlet, and the patient can take out the sub-packaging bags from there.

[0029] Also, the present invention relates to a method for detecting a seam portion between sub-packaging bags using an imaging device including a camera, a first polarizer, and a second polarizer. The second polarizer is disposed between the camera and the first polarizer. The method according to the present invention includes disposing a strip of sub-packaging bags between the first polarizer and the second polarizer, capturing a first image of the first surface of the strip of sub-packaging bags with the camera, changing the polarization direction of the first polarizer or the second polarizer, capturing a second image of the first surface of the strip of sub-packaging bags with the camera, combining the first image and the second image into a false-color image, and processing the false-color image to detect the seam portion.

[0030] In the method according to the present invention, a camera captures a first image and a second image of the first surface of a strip of a packaging bag through a second polarizer. The polarization direction of the first or second polarizer is changed between the time the first image is captured and the time the second image is captured. Due to the polarization effect and birefringence, the seam area is highlighted in different ways in the first and second images. In the method according to the present invention, the first and second images are combined to form a false color image. This is done by combining the first and second images using two different color channels. If the first and second images are not monochrome images, they are converted to monochrome images before being combined into a false color image. The false color image can be a false color RG (red-green), false color RB (red-blue), or false color GB (green-blue). The false color image is processed to detect the seam area.

[0031] The method according to the present invention can be used in a drug packaging machine to detect the seam between two packaging bags. After the seam between two packaging bags is detected, the strip can be cut transversely at the seam using a cutting device.

[0032] An advantage of the method according to the present invention is that it can accurately detect the seam between individual packaging bags.

[0033] According to one embodiment of the present invention, when one of the first image and the second image is captured, the polarization directions of the first polarizer and the second polarizer are perpendicular, and when the other of the first image and the second image is captured, the polarization directions of the first polarizer and the second polarizer are parallel.

[0034] According to one embodiment of the present invention, the method includes illuminating a second surface of the packaging bag strip through a first polarizer when a first image and a second image are being captured. The imaging device may include a first light source for illuminating the second surface of the packaging bag strip and a control unit configured to switch the first light source on and off.

[0035] According to one embodiment of the present invention, the method includes capturing a third image of a first surface of a strip of a packaging bag with a camera, illuminating the first surface of the strip of the packaging bag when the third image is captured, combining the first image, the second image and the third image to form a false color image instead of combining the first image and the second image to form a false color image, and processing the false color image to detect seam portions.

[0036] The first, second, and third images are combined into a false-color image using three different color channels. If the first, second, and third images are not monochrome, they are converted to monochrome before being combined into the false-color image. The false-color image can be a false-color RGB (red, green, blue) image. The false-color image is processed to detect seams.

[0037] The imaging device may include a second light source for illuminating a first surface of the packaging strip and a control unit configured to switch the second light source on and off. The second light source is preferably turned off when the first and second images are being captured.

[0038] If the imaging device includes a first light source for illuminating a second surface of the packaging bag strip through a first polarizer, the first light source is preferably turned off when a third image is being captured.

[0039] According to one embodiment of the present invention, the method includes recognizing text in a third image using neural network-based optical character recognition. The text in the third image may include patient information and drug-related information, which may include a patient identifier (e.g., name and / or identification number) as well as the date and time of drug dispensing. The text may be printed in a specific layout directly on the surface of the dispensing bag or on a label affixed to the dispensing bag.

[0040] According to one embodiment of the present invention, false-color images are processed using a neural network. The neural network can be trained on a large number of images in which seam areas have been manually labeled. The neural network creates a heatmap indicating the location of the seam areas. Based on the heatmap, the cutting of the strips of the packaging bag is determined.

[0041] According to one embodiment of the present invention, the method includes a step of reducing the resolution of a false-color image before the step of processing the false-color image to detect seam areas. The image resolution is reduced to reduce the computational load on the neural network.

[0042] The exemplary embodiments of the invention presented herein should not be construed as limiting the scope of the appended claims. In this document, the verb “comprise” is used as an open limitation, not excluding the existence of features not described herein. Features described in the dependent claims may be freely combined with each other unless otherwise specified.

[0043] The exemplary embodiments and their advantages presented herein are related to the relevant parts of the imaging apparatus and method according to the present invention, even if not specifically mentioned. [Brief explanation of the drawing]

[0044] [Figure 1] This shows an imaging device according to a first embodiment of the present invention. [Figure 2] An imaging device according to a second embodiment of the present invention is shown. [Figure 3] This shows a drug packaging machine according to one embodiment of the present invention. [Figure 4] A flowchart of the method according to one embodiment of the present invention is shown. [Modes for carrying out the invention]

[0045] In different embodiments, the same reference numerals are used for identical or similar components.

[0046] Figure 1 shows an imaging device according to a first embodiment of the present invention. The imaging device 100 is used to image a strip 200 of a packaging bag. The strip 200 shown in Figure 1 consists of two packaging bags 201 and 202. Between the packaging bags 201 and 202 is a seam portion 203 from which the strip 200 should be cut to separate the packaging bags 201 and 202 from each other.

[0047] The imaging device 100 includes two polarizers 101 and 102 between which a strip 200 is positioned, and a camera 103 that images the underside of the strip 200 through polarizer 102. The imaging device 100 also includes a control unit 104 connected to polarizer 101 and configured to change the polarization direction of polarizer 101 between a first polarization direction in which the polarization directions of polarizers 101 and 102 are perpendicular, and a second polarization direction in which the polarization directions of polarizers 101 and 102 are parallel.

[0048] The imaging device 100 includes a light source 105 positioned spaced apart from the upper surface of the polarizer 101. The light source 105 is used to illuminate the upper surface of the strip 200 through the polarizer 101. The amount and polarization state of light incident on the camera 103 from the light source 105 depend not only on the properties of the strip 200 through which the light passes, but also on the polarization directions of the polarizers 101 and 102. The imaging device 100 includes a control unit 106 connected to the light source 105 and configured to switch the light source 105 on and off.

[0049] The imaging device 100 includes a reflector 107 positioned in the space between polarizers 101 and 102, with its aperture 108 facing the lower surface of the strip 200, and a light source 109 attached to the aperture 108 of the reflector 107. The reflector 107 is used to reflect light from the light source 109 toward the lower surface of the strip 200. Some of the light is reflected from the lower surface of the strip 200, passes through the polarizer 102, and enters the camera 103. The reflector 107 is equipped with an aperture (not shown in Figure 1), through which the lower surface of the strip 200 is imaged. The amount and polarization state of light incident from the light source 109 to the camera 103 depend not only on the characteristics of the strip 200 but also on the polarization direction of the polarizer 102. A control unit 106 is connected to the light source 109 and is configured to switch the light source 109 on and off.

[0050] Camera 103 is configured to capture images of the strip 200 using different polarization directions of the polarizer 101 and different settings of the light sources 105 and 109. The imaging device 100 includes a processing unit 110 connected to camera 103 and configured to process the captured images in order to determine patient information and drug-related information of the packaging bags 201 and 202.

[0051] Figure 2 shows an imaging device according to a second embodiment of the present invention. The imaging device 100 is used to image a strip 200 of a packaging bag. The strip 200 shown in Figure 2 consists of two packaging bags 201 and 202. Between the packaging bags 201 and 202 is a seam portion 203 from which the strip 200 should be cut to separate the packaging bags 201 and 202 from each other. The strip 200 is placed on a transparent panel 111.

[0052] The imaging device 100 includes two polarizers 101 and 102 between which a strip 200 is positioned, and a camera 103 that images the upper surface of the strip 200 through the polarizer 102. The imaging device 100 also includes a control unit 104 connected to the polarizer 102 and configured to change the polarization direction of the polarizer 102 between a first polarization direction in which the polarization directions of polarizers 101 and 102 are perpendicular, and a second polarization direction in which the polarization directions of polarizers 101 and 102 are parallel.

[0053] The imaging device 100 includes a light source 105 positioned in contact with the underside of the polarizer 101. The light source 105 is used to illuminate the underside of the strip 200 through the polarizer 101. The amount and polarization state of light incident from the light source 105 to the camera 103 depend on the properties of the strip 200 and the transparent panel 111 through which the light passes, as well as the polarization directions of the polarizers 101 and 102. The imaging device 100 includes a control unit 106 connected to the light source 105 and configured to switch the light source 105 on and off.

[0054] The imaging device 100 includes a reflector 107 positioned in the space between polarizers 101 and 102, with its aperture 108 facing the upper surface of the strip 200, and a light source 109 attached to the aperture 108 of the reflector 107. The reflector 107 is used to reflect light from the light source 109 toward the upper surface of the strip 200. Some of the light is reflected from the upper surface of the strip 200, passes through the polarizer 102, and enters the camera 103. The reflector 107 is equipped with an aperture 112 through which the upper surface of the strip 200 is imaged. The amount and polarization state of light incident from the light source 109 to the camera 103 depend not only on the characteristics of the strip 200 but also on the polarization direction of the polarizer 102. A control unit 106 is connected to the light source 109 and is configured to switch the light source 109 on and off.

[0055] Camera 103 is configured to capture images of the strip 200 using different polarization directions of the polarizer 102 and different settings of the light sources 105 and 109. The imaging device 100 is connected to camera 103 and includes a processing unit 110 configured to process the captured images in order to detect the position of the seam portion 203 between the packaging bags 201 and 202 and to recognize the text printed on the top surfaces of the packaging bags 201 and 202.

[0056] Figure 3 shows a drug packaging machine according to one embodiment of the present invention for dispensing medication to a patient. The drug packaging machine 300 comprises a chamber 301 into which strips 200 of packaging bags are inserted. The strips 200 are made up of packaging bags 201 joined together. Each packaging bag 201 contains medication that the patient is to take at a predetermined time. The packaging bags 201 are transported from the chamber 301 to the outlet 302 of the drug packaging machine 300 using a pair of rollers 303 that are rotated in opposite directions by an electric motor 304.

[0057] The drug packaging machine 300 includes the imaging device 100 shown in Figure 2. The imaging device 100 is shown in a rectangular shape in Figure 3. The imaging device 100 is used to detect the seam portion 203 between the packaging bags 201 and to recognize text printed on the packaging bags 201. The text is, for example, the date and time of prescription of the drug.

[0058] The drug packaging machine 300 includes a cutting device 305 configured to cut the strip 200 transversely at the seam portion 203 detected by the imaging device 100. The separated packaging bags 201 are transported to an outlet 302, from which the patient can remove the packaging bags 201.

[0059] The drug packaging machine 300 includes an electric motor 304, an imaging device 100, and a cutting device 305, and a control unit 306 configured to control their operation.

[0060] Figure 4 shows a flowchart of a method according to one embodiment of the present invention for detecting seams between dispensing bags. In step 401, a strip of dispensing bags is placed between a first polarizer and a second polarizer. In step 402, a first image of a first surface of the strip of dispensing bags is captured by a camera. The camera is positioned to capture the strip of dispensing bags through a second polarizer. In step 403, the polarization direction of either the first or second polarizer is changed. In step 404, a second image of the first surface of the strip of dispensing bags is captured by the camera. In step 405, the first and second images are combined to form a false-color image. In step 406, the false-color image is processed to detect seams.

[0061] The drawings depict only advantageous exemplary embodiments of the present invention. It will be apparent to those skilled in the art that the present invention is not limited to the examples described above and can be modified within the scope of the claims presented below. While several possible embodiments of the present invention are described in the dependent claims, they should not be construed as limiting the scope of protection of the present invention.

Claims

1. A first polarizer and a second polarizer that can be positioned between the strips of the packaging bag, A camera for imaging the first surface of the strip of the packaging bag through the second polarizer, Means for changing the polarization direction of the first polarizer or the second polarizer An imaging device characterized by comprising:

2. The imaging apparatus according to claim 1, characterized in that the means for changing the polarization direction of the first polarizer or the second polarizer is configured to change the polarization direction between a first polarization direction in which the polarization directions of the first polarizer and the second polarizer are perpendicular and a second polarization direction in which the polarization directions of the first polarizer and the second polarizer are parallel.

3. The imaging device according to claim 1 or 2, further comprising a first light source for illuminating the second surface of the strip of the packaging bag through the first polarizer.

4. The imaging device according to any one of claims 1 to 3, characterized in that the imaging device comprises a second light source for illuminating the first surface of the strip of the packaging bag.

5. The imaging device according to claim 4, further comprising a reflector for reflecting light from the second light source toward the first surface of the strip of the packaging bag, wherein the reflector has an aperture, and the first surface of the strip of the packaging bag can be imaged through the aperture.

6. The imaging device according to claim 5, characterized in that the reflector is a tunnel-type reflector.

7. The imaging apparatus according to claim 5 or 6, characterized in that the second light source is attached to the opening of the reflector.

8. The imaging device according to any one of claims 1 to 7, characterized in that it comprises a transparent panel for supporting the strip of the packaging bag.

9. A drug packaging machine characterized by comprising at least one imaging device as described in any one of claims 1 to 8.

10. A method for detecting seam portions between dispensing bags using an imaging device comprising a camera, a first polarizer, and a second polarizer, wherein the second polarizer is positioned between the camera and the first polarizer, and the method is The strip of the packaging bag is placed between the first polarizer and the second polarizer, The camera captures a first image of the first surface of the strip of the aforementioned packaging bag, Changing the polarization direction of the first polarizer or the second polarizer, The camera captures a second image of the first surface of the strip of the packaging bag, The first image and the second image are combined to form a false-color image, Processing the false color image in order to detect the seam portion. A method characterized by including the following.

11. The method according to 10, characterized in that when one of the first and second images is captured, the polarization directions of the first polarizer and the second polarizer are perpendicular, and when the other of the first and second images is captured, the polarization directions of the first polarizer and the second polarizer are parallel.

12. The method according to 10 or 11, characterized in that when the first image and the second image are captured, the second surface of the strip of the packaging bag is illuminated through the first polarizer.

13. The method described above is The camera captures a third image of the first surface of the strip of the packaging bag, When the third image is captured, the first surface of the strip of the packaging bag is illuminated, Instead of combining the first image and the second image to create a false color image, the first image, the second image, and the third image are combined to create a false color image. Processing the false color image in order to detect the seam portion. A method according to any one of claims 10 to 12, characterized by including the following:

14. The method according to 13, characterized in that it includes recognizing text in the third image using neural network-based optical character recognition.

15. The method according to any one of claims 10 to 14, characterized in that the false color image is processed using a neural network.

Images