Inspection apparatus, inspection method, and program

Patent metadata

Field	Value
Publication number	US-9689806-B2
Application number	US-201615290020-A
Country	US
Kind code	B2
Filing date	Oct 11, 2016
Priority date	Jun 9, 2014
Publication date	Jun 27, 2017
Grant date	Jun 27, 2017

Abstract

To facilitate adjusting of a distance from an inspection target to an illumination section by providing a movable illumination section that is movable independently of the imaging section. An illumination apparatus has a plurality of LEDs arranged in a substantially annular form, a light diffusion member for diffusing light emitted from the plurality of LEDs, and a lighting control part for lighting the plurality of light sources in accordance with a predetermined lighting pattern when designated to start lighting. In particular, the illumination apparatus moves independently of a camera to adjust a distance to a workpiece.

First claim

What is claimed is:

1. An inspection apparatus comprising:
an imaging section for capturing an image of an inspection target;
an illumination section which has a plurality of light segments arranged in a substantially annular form to illuminate the inspection target from three or more illumination directions, a storage part to store a lighting data including order information indicating order of lighting the light segments and interval information indicating a lighting interval of the plurality of light segments, and a lighting control part for lighting the plurality of light segments in accordance with the order information and the interval information stored in the storage part when designated to start lighting, and which moves independently of the imaging section to adjust a distance to the inspection target;
an inspection image generating section for synthesizing a plurality of luminance images, acquired by the imaging section, by a photometric stereo method to generate an inspection image having a plurality of pixel values in accordance with inclination or a reflectance of a surface of the inspection target; and
a determination section for determining defectiveness/non-defectiveness of the inspection target by using the inspection image.

2. The inspection apparatus according to claim 1 , wherein the illumination section has a first substrate on which the plurality of light sources of light segments are mounted, and a second substrate on which the lighting control part is mounted.

3. The inspection apparatus according to claim 1 , wherein the storage part stores lighting pattern information, wherein each lighting pattern information includes a plurality of lighting patterns.

4. The inspection apparatus according to claim 3 , wherein the lighting patterns includes a first lighting pattern which illuminates the inspection target from four directions sequentially and a second lighting pattern which illuminates the inspection target with lighting all light segments simultaneously.

5. The inspection apparatus according to claim 2 , wherein
the plurality of light sources are connected in series, and
a switch capable of being switched on/off by the lighting control part is connected in parallel to each of the plurality of light sources.

6. The inspection apparatus according to claim 2 , further comprising
a variable power source for supplying a voltage to the plurality of light sources;
a variable constant current source for adjusting a current that flows through the plurality of light sources; and
a main switch for switching on/off of the variable constant current source,
wherein, after a voltage supplied by the variable power source becomes sufficiently high, the lighting control part switches a switch that is connected in parallel to each of the plurality of light sources in accordance with the lighting pattern, and switches on the main switch, to light any of the plurality of light sources in accordance with the lighting pattern.

7. The inspection apparatus according to claim 6 , wherein the lighting control part controls a voltage of the variable power source in accordance with a voltage value that is fed back from the variable constant current source such that an overvoltage is not applied to the variable constant current source.

8. The inspection apparatus according to claim 1 , further comprising:
a setting section for setting a flaw inspection region for the inspection image; and
a flaw inspecting section for inspecting a flaw in the flaw inspection region,
wherein the determination section determines defectiveness/non-defectiveness of the inspection target based on a result of inspection by using the inspection image by the flaw inspecting section.

9. The inspection apparatus according to claim 1 , further comprising:
a setting section for setting a character recognition region for the inspection image; and
a character recognizing section for recognizing a character in the character recognition region,
wherein the determination section determines defectiveness/non-defectiveness of the inspection target based on a result of recognition by using the inspection image by the character recognizing section.

10. The inspection apparatus according to claim 1 , further comprising
an adjustment section for adjusting a characteristic size which is a parameter that is required at the time of creating the inspection image.

11. The inspection apparatus according to claim 10 , wherein the inspection image generating section generates a plurality of inspection images based on respectively different characteristic sizes designated by the adjustment section.

12. The inspection apparatus according to claim 1 , wherein the inspection image generating section generates, as the inspection image, a surface shape image based on a normal vector of the surface of the inspection target or a texture image based on a reflectance of the surface of the inspection target.

Assignees

• Keyence Co Ltd

Inventors

• Matsuda Hajime

Classifications

• G01N21/8806 Primary

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• G06K9/2027

  Physics · mapped topic

• G01N2021/845

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• G06T7/0004

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• G01N2201/062

  LED's · CPC title