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EP-4396567-B1 - IMAGE ACQUISITION APPARATUS, INSPECTION APPARATUS, AND IMAGE ACQUISITION METHOD

EP4396567B1EP 4396567 B1EP4396567 B1EP 4396567B1EP-4396567-B1

Inventors

  • MASUDA, KOJI
  • HINO, MAKOTO
  • HIRAKAWA, MAKOTO

Dates

Publication Date
20260513
Application Date
20220805

Claims (8)

  1. An inspection apparatus comprising: an image acquisition apparatus comprising: a light emitting unit (31) configured to emit light to a sealing portion (52) of a package (50) including a light energy absorbing material (51), the light having a wavelength absorbed by the light absorbing material (51); a light receiving unit (32) configured to receive thermal radiation from the sealing portion (52) as thermal information; and an image acquisition unit (402) configured to acquire two-dimensional thermal information on the sealing portion (52) as a two-dimensional image through the light receiving unit (32), wherein the package (50) is disposed between the light emitting unit (31) and the light receiving unit (32), characterised in that : the two-dimensional image acquisition unit (402) acquires at least one two-dimensional image at a time t satisfying a condition below: 0 < t < T where 0 is a time when the light emitting unit (31) emits the light to one side of the sealing portion (52) and T is a time when surface temperature of the other side of sealing portion (52) reaches peak temperature,; and a pass-or-fail determination unit (403) configured to determine whether the sealing portion (52) is pass or fail through the two-dimensional image acquired by the image acquisition unit (402), wherein the pass-or-fail determination unit (403) controls the image acquisition unit (402) to acquire at least one two-dimensional image at a time t satisfying a condition below: 0 < t < T / 2 .
  2. The inspection apparatus according to claim 1, wherein the light receiving unit (32) is arranged not to directly receive the light emitted from the light emitting unit (31) and passed through the sealing portion (52) and the light emitted from the light emitting unit (31) and reflected the sealing portion (52).
  3. The inspection apparatus according to claim 1 or 2, wherein the light emitting unit (31) emits light to the sealing portion (52) as one shot, and the light receiving unit (32) receives thermal radiation form the sealing portion (52) as one shot.
  4. The inspection apparatus according to any preceding claim, wherein the light emitting unit (31) is an area light source in which point light sources are arranged in vertical and horizontal directions.
  5. The inspection apparatus according to any preceding claim, wherein the two-dimensional image includes multiple two-dimensional images.
  6. The inspection apparatus according to claim 5, wherein the multiple two-dimensional images are consecutive multiple two-dimensional images acquired by the image acquisition unit (402) at a certain interval.
  7. The inspection apparatus according to any preceding claim, wherein the pass-or-fail determination unit (403) controls the image acquisition unit (402) to acquire at least one two-dimensional image at a time t satisfying a condition below: t < 0 and executes a noise removing process on the at least one two-dimensional image acquired at the time t.
  8. An image acquiring and inspecting method comprising: emitting light by a light emitting unit (31) to a sealing portion (52) of a package (50) including a light energy absorbing material (51), the light having a wavelength absorbed by the light energy absorbing material (51); receiving thermal radiation from the sealing portion (52) by a light receiving unit (32) as thermal information; and acquiring two-dimensional thermal information on the sealing portion (52) as a two-dimensional image through the light receiving unit (32), wherein the package is disposed between the light emitting unit (31) and the light receiving unit (32), characterised in that : the acquiring includes acquiring at least one two-dimensional image at a time t satisfying a condition below: 0 < t < T where 0 is a time when the light emitting unit (31) emits light to one side of the sealing portion (52), and T is a time when surface temperature of the other side of sealing portion (52) reaches a peak temperature, determining by a pass-or-fail determination unit (403) whether the sealing portion (52) is pass or fail through the two-dimensional image acquired by the image acquisition unit (402), wherein the pass-or-fail determination unit (403) controls the image acquisition unit (402) to acquire at least one two-dimensional image at a time t satisfying a condition below: 0 < t < T / 2 .

Description

[Technical Field] The present disclosure relates to an image acquisition apparatus, an inspection apparatus, and an image acquisition method. [Background Art] A package inspection apparatus for inspecting a package including a content such as food inside the package by sealing the package is known The inspection apparatus inspects a sealing portion of the package to check whether the sealing portion is correctly sealed or not. For example, an apparatus for inspecting a sealing failure of a package is disclosed in PLT1. The configuration of the apparatus includes an inspection means for detecting a failure of a sealing portion based on temperature of the package by heating the package using a heat means. [Citation List] [Patent Literature] [PTL 1] Japanese Unexamined Patent Application Publication No. 2020-041840. WO-A-2015/140797 discloses methods and systems for determining integrity of a package. US-A-2008/302707 discloses an automatic process and machine for inspecting and sorting non-metallic objects. JP-A-2017067549 discloses an article inspection device capable of inspecting an entire seal area of an object under inspection. [Summary of Invention] [Technical Problem] However, in the conventional inspection apparatus for a package, since a heat source is used to increase the temperature of the package, handling of the heat source is complicated in terms of safety, and heat generated from the heat source adversely affects peripheral members. An aim of the present invention is to acquire a high-quality thermal image without causing adverse thermal effects on the peripheral members. [Solution to Problem] The invention is set out in independent apparatus claim 1 and corresponding method claim 8. Further embodiments are defined by the dependent claims. [Advantageous Effects of Invention] According to the embodiments of the present invention, a high-quality thermal image can be acquired without causing adverse thermal effects on the peripheral members. [Brief Description of Drawings] The accompanying drawings are intended to depict example embodiments of the present invention and should not be interpreted to limit the scope thereof. The accompanying drawings are not to be considered as drawn to scale unless explicitly noted. Also, identical or similar reference numerals designate identical or similar components throughout the several views. [FIG. 1] FIG. 1 is a diagram of a configuration of an inspection apparatus according to an embodiment:[FIG. 2] FIG. 2 is a diagram of a package to be inspected by the inspection apparatus;[FIG. 3] FIG. 3 is a diagram of a configuration of the package material;[FIG. 4] FIG. 4 is a graph of the absorbance of aluminum;[FIG. 5] FIG. 5 is a diagram of a point light source to emit light on the package being conveyed;[FIG. 6] FIG. 6 is a diagram of a point light source to emit light on the package being stopped;[FIG. 7] FIG. 7 is a diagram of a line light source to emit light on the package being conveyed;[FIG. 8] FIG. 8 is a diagram of a line light source to emit light on the package being stopped;[FIG. 9] FIG. 9 is a diagram of an area light source to emit light on the package being conveyed;[FIG. 10] FIG. 10 is a diagram of an area light source to emit light on the package being stopped;[FIG. 11] FIG. 11 is a diagram of a point light receiving element to receive thermal radiation from the package being conveyed;[FIG. 12] FIG. 12 is a diagram of a point light receiving element to receive thermal radiation from the package being stopped;[FIG. 13] FIG. 13 is a diagram of a line light receiving element to receive thermal radiation from the package being conveyed;[FIG. 14] FIG. 14 is a diagram of a line light receiving element to receive thermal radiation from the package being stopped;[FIG. 15] FIG. 15 is a diagram of an area light receiving element to receive thermal radiation from the package being conveyed;[FIG. 16] FIG. 16 is a diagram of an area light receiving element to receive thermal radiation from the package being stopped;[FIG. 17] FIG. 17 is a diagram of a first layout of the light emitting unit and the light receiving unit;[FIG. 18] FIG. 18 is a diagram of a second layout of the light emitting unit and the light receiving unit;[FIG. 19] FIG. 19 is a diagram of a third layout of the light emitting unit and the light receiving unit;[FIG. 20] FIG. 20 is a block diagram of a hardware configuration of the control device;[FIG. 21] FIG. 21 is a functional block diagram of the functions of the control device;[FIG. 22] FIG. 22 is a graph of change in surface temperature between a position in a normal state and a position in an anomaly state;[FIG. 23] FIG. 23 is a two-dimensional image related to determination of pass-or-fail for the sealing portion.[FIG. 24] FIG. 24 is a graph of a differential value of the surface temperature over time; and[FIG. 25] FIG. 25 is an illustration of a two-dimensional image processed by using multiple images related to determination of the pass o