JP-7856457-B2 - Inspection equipment, inspection method, and program

Inventors

• 森 千夏

Assignees

• 株式会社東芝

Dates

Publication Date

20260511

Application Date

20220323

Claims (11)

1. An imaging unit including a polarizing camera positioned above the object to be inspected, The system includes a processing unit that controls the imaging unit and processes an image of the surface of the object to be inspected , which is illuminated by the illumination unit and captured by the imaging unit, The surface of the object to be inspected includes a repeating pattern in which a plurality of regions, including a first region, are arranged in an array on a plane, The illumination unit includes a first illumination that illuminates the surface from a first direction, and a second illumination that illuminates the surface from a second direction opposite to the first direction when viewed from above . The imaging unit acquires imaging data including information of a first image of the plurality of regions illuminated by the first illumination and the second illumination , and information of a second image of the plurality of regions illuminated by the first illumination and the second illumination. The aforementioned processing unit, Based on the first region image of the first region based on the first captured image and the second region image of the first region based on the second captured image, a first difference image corresponding to the difference between the first region image and the second region image is calculated. Based on the first difference image, the defective region in the first region is determined . The first illumination emits first illumination light polarized in a first polarization direction, The second illumination emits a second illumination light polarized in a second polarization direction, The first captured image is an image of light polarized in the first polarization direction, The second captured image is an image of light polarized in the second polarization direction, An inspection apparatus in which the first image and the second image are created from imaging data obtained by a single imaging operation under the condition that the first illumination light is irradiated onto the surface from the first illumination and the second illumination light is irradiated onto the surface from the second illumination .
2. The aforementioned multiple regions include a second region, The inspection apparatus according to claim 1, wherein the processing unit determines a defective area in the second region based on a difference image corresponding to the difference between a region image of the second region based on the first captured image and a region image of the second region based on the second captured image .
3. An imaging unit including a camera positioned above the object to be inspected, The system includes a processing unit that controls the imaging unit and processes an image of the surface of the object to be inspected, which is illuminated by the illumination unit and captured by the imaging unit, The surface of the object to be inspected includes a plurality of regions, including the first region. The illumination unit includes a first illumination that illuminates the surface from a first direction, and a second illumination that illuminates the surface from a second direction opposite to the first direction when viewed from above. The imaging unit acquires imaging data including information of a first image of the plurality of regions illuminated by the first illumination and information of a second image of the plurality of regions illuminated by the second illumination. The aforementioned processing unit, Based on the first region image of the first region based on the first captured image and the second region image of the first region based on the second captured image, a first difference image corresponding to the difference between the first region image and the second region image is calculated. Based on the first difference image, the defective region in the first region is determined. The first image is an image of the surface irradiated by the first illumination, captured under the first imaging conditions. The inspection apparatus wherein the second image is an image of the surface irradiated by the second illumination, captured under second imaging conditions different from the first imaging conditions.
4. The aforementioned multiple regions include a second region, The imaging unit acquires a third image obtained by imaging the surface irradiated by the first illumination under imaging conditions different from the first imaging conditions, and a fourth image obtained by imaging the surface irradiated by the second illumination under imaging conditions different from the second imaging conditions. The aforementioned processing unit, Based on the third region image of the second region based on the third captured image and the fourth region image of the second region based on the fourth captured image, a second difference image corresponding to the difference between the third region image and the fourth region image is calculated. The inspection apparatus according to claim 3 , which determines a defect region in the second region based on the second difference image.
5. The processing unit calculates a first polarization image, which is an image of the first illumination light, based on the first captured image. The inspection apparatus according to claim 1, wherein the processing unit divides one of the first captured image and the first polarized image into a plurality of regions, corrects the brightness of the plurality of regions so that the contrast of the plurality of regions is equal to that of the plurality of regions, and calculates a first region image based on the corrected one of the first captured image and the first polarized image.
6. A method for inspecting the surface of an object to be inspected , which includes a repeating pattern in which multiple regions, including a first region, are arranged in an array on a plane , A first image of the plurality of regions illuminated by a first illumination that shines on the surface from a first direction and a second illumination that shines on the surface from a second direction opposite to the first direction when viewed from above , and a second image of the plurality of regions illuminated by the first illumination and the second illumination are acquired. Based on the first region image of the first region based on the first captured image and the second region image of the first region based on the second captured image, a first difference image corresponding to the difference between the first region image and the second region image is calculated. Based on the first difference image, the defective region in the first region is determined . The first illumination emits first illumination light polarized in a first polarization direction, The second illumination emits a second illumination light polarized in a second polarization direction, The first captured image is an image of light polarized in the first polarization direction, The second captured image is an image of light polarized in the second polarization direction, An inspection method in which the first image and the second image are obtained by taking images in a single imaging operation under the condition that the first illumination light is irradiated onto the surface from the first illumination and the second illumination light is irradiated onto the surface from the second illumination .
7. A method for inspecting the surface of an object to be inspected, which includes a plurality of regions including a first region, A first image of the plurality of regions illuminated by a first illumination from a first direction, and a second image of the plurality of regions illuminated by a second illumination from a second direction opposite to the first direction when viewed from above, are acquired. Based on the first region image of the first region based on the first captured image and the second region image of the first region based on the second captured image, a first difference image corresponding to the difference between the first region image and the second region image is calculated. Based on the first difference image, the defective region in the first region is determined. The first image is an image of the surface irradiated by the first illumination, captured under the first imaging conditions. An inspection method wherein the second image is an image of the surface irradiated by the second illumination, captured under second imaging conditions different from the first imaging conditions.
8. The aforementioned multiple regions include a second region, A third image is obtained by capturing the surface irradiated by the first illumination under imaging conditions different from the first imaging conditions, and a fourth image is obtained by capturing the surface irradiated by the second illumination under imaging conditions different from the second imaging conditions. Based on the third region image of the second region based on the third captured image and the fourth region image of the second region based on the fourth captured image, a second difference image corresponding to the difference between the third region image and the fourth region image is calculated. The inspection method according to claim 7 , wherein a defect region in the second region is determined based on the second difference image.
9. Based on the first captured image, a first polarized image, which is an image of the first illumination light, is calculated. The inspection method according to claim 6, comprising dividing one of the first captured image and the first polarized image into a plurality of regions, correcting the brightness of the plurality of regions so that the contrast of the plurality of regions is equal to that of the plurality of regions, and calculating a first region image based on the corrected one of the first captured image and the first polarized image.
10. A program for inspecting the surface of an object to be inspected , which includes a repeating pattern in which multiple regions, including a first region, are arranged in an array on a plane , On the computer, Based on a first region image of the first region, which is based on first captured images of the plurality of regions illuminated by a first illumination that illuminates the surface from a first direction and a second illumination that illuminates the surface from a second direction opposite to the first direction when viewed from above, and a second region image of the first region, which is based on second captured images of the plurality of regions illuminated by the first illumination and the second illumination, a first difference image corresponding to the difference between the first region image and the second region image is calculated. This is a program that determines the defect region in the first region based on the first difference image. The first illumination emits first illumination light polarized in a first polarization direction, The second illumination emits a second illumination light polarized in a second polarization direction, The first captured image is an image of light polarized in the first polarization direction, The second captured image is an image of light polarized in the second polarization direction, The first captured image and the second captured image are obtained by a single imaging operation in which the first illumination light is shone onto the surface from the first illumination and the second illumination light is shone onto the surface from the second illumination .
11. A program for inspecting the surface of an object to be inspected, which includes multiple regions including a first region, On the computer, Based on a first region image of the first region, which is based on first captured images of the plurality of regions illuminated by a first illumination from a first direction, and a second region image of the first region, which is based on second captured images of the plurality of regions illuminated by a second illumination from a second direction opposite to the first direction when viewed from above, a first difference image corresponding to the difference between the first region image and the second region image is calculated. This is a program that determines the defect region in the first region based on the first difference image. The first image is an image of the surface irradiated by the first illumination, captured under the first imaging conditions. The program provides a second image, which is an image of the surface illuminated by the second illumination, captured under second imaging conditions different from the first imaging conditions.

Description

Embodiments of the present invention relate to an inspection apparatus, an inspection method, and a program. For example, there are inspection devices, inspection methods, and programs for inspecting the appearance of objects such as circuit boards. The inspection detects defects such as surface irregularities in the object being inspected. Japanese Patent Publication No. 2017-156212 This is a schematic diagram illustrating an inspection apparatus according to the first embodiment.This is a schematic plan view illustrating an example of an object to be inspected.This is a schematic plan view illustrating a part of the inspection apparatus according to the first embodiment.This is a flowchart illustrating an inspection method in the inspection apparatus according to the first embodiment.This is a flowchart illustrating the process of determining a defective area in the inspection apparatus according to the first embodiment.Figures 6(a) to 6(e) are schematic diagrams illustrating images in the inspection apparatus according to the first embodiment.This is a schematic diagram illustrating an image in the inspection apparatus according to the first embodiment.This is a flowchart illustrating the process of calculating multiple region images in an inspection apparatus according to the first embodiment.Figures 9(a) to 9(c) are schematic diagrams illustrating the process of detecting multiple region images in an inspection apparatus according to the first embodiment.Figures 10(a) to 10(c) are schematic diagrams illustrating the process of correcting brightness in an inspection apparatus according to the first embodiment.This is a flowchart illustrating an inspection method in the inspection apparatus according to the first embodiment.This is a schematic diagram illustrating an inspection apparatus according to the second embodiment.This is a schematic diagram illustrating an image captured in an inspection apparatus according to the second embodiment.This table illustrates combinations of captured images in the inspection apparatus according to the second embodiment. Each embodiment of the present invention will be described below with reference to the drawings. Drawings are schematic or conceptual, and the relationships between the thickness and width of each part, as well as the ratios of the sizes of different parts, are not necessarily identical to those of reality. Even when representing the same part, the dimensions and ratios may be depicted differently in different drawings. In this specification and in each figure, elements similar to those already described are denoted by the same reference numerals, and detailed explanations are omitted as appropriate. (First embodiment) Figure 1 is a schematic diagram illustrating an inspection apparatus according to the first embodiment. The inspection apparatus 100 (inspection system) according to this embodiment includes a processing unit 30. The inspection apparatus 100 may further include an imaging unit 10, an illumination unit 20, and an output unit 40. The inspection device 100 acquires an image of the surface of the object to be inspected W (workpiece) and detects surface shape defects such as irregularities on the surface of the object to be inspected W based on the obtained image. The illumination unit 20 illuminates the surface Wf of the object W being inspected. As shown in Figure 1, the illumination unit 20 is positioned, for example, diagonally above the surface Wf, and irradiates the surface Wf with illumination light L from an oblique angle. The illumination unit 20 is, for example, a low-angle illumination. As will be described later, in this example, the illumination light L is polarized. The imaging unit 10 images the surface Wf of the object W to be inspected. For example, the imaging unit 10 is a camera positioned above the object W to be inspected. As will be described later, in this example, the imaging unit 10 is a polarizing camera. The processing unit 30 processes the image captured by the imaging unit 10. The processing unit 30 includes, for example, a computing device such as a computer. The processing unit 30 includes a communication interface and is connected to the imaging unit 10 and the illumination unit 20 by wired or wireless means, and is capable of communicating with the imaging unit 10 and the illumination unit 20. For example, the processing unit 30 can control the operation of the imaging unit 10 and the illumination unit 20. However, in this embodiment, the operation of the imaging unit 10 and the illumination unit 20 does not necessarily have to be controlled by the processing unit 30. The processing unit 30 includes a storage unit 31 and an arithmetic unit 32. The image (imaging data) captured by the imaging unit 10 is input to the processing unit 30 and processed by the arithmetic unit 32. Specifically, the arithmetic unit 32 includes electronic circuits such as a CPU (Central Processing Unit). The storage unit 31 stores a p