Identifying defects in transparent containers

• US 10,422,755 B2
• Filed: 12/07/2016
• Issued: 09/24/2019
• Est. Priority Date: 12/07/2016
• Status: Active Grant

• Current Assignee: Applied Vision Corporation (Antares Vision S.p.A.)
• Original Assignee: Applied Vision Corporation (Antares Vision S.p.A.)
• Inventors: Sones, Richard A., Kress, Michael Leo, Brumbaugh, Kris, Reusser, Kellen
• Primary Examiner(s): Harvey, David E
• Application Number:
  US15/372,047
• Publication Number:
  US 20180156740A1
• Time in Patent Office: 1,021 Days
• CPC Class Codes: G01N 2021/8845 Multiple wavelengths of illumination or detection
• CPC Class Codes: G01N 21/90 in a container or its contents G01N21/91 takes precedence
• CPC Class Codes: G01N 21/9036 using arrays of emitters or receivers
• CPC Class Codes: G01N 2201/0627 Use of several LED's for spectral resolution

Abstract

Described herein are various technologies related to inspecting transparent containers for both opaque and transparent defects. An emitter is configured to direct a color gradient through a sidewall of a transparent container, such that color of light that passes through the sidewall varies across the sidewall. A camera is configured to capture an image of the sidewall of the transparent container while the color gradient passes through the sidewall of the container. A computing system receives the image and determines whether the sidewall of the container includes either an opaque or a transparent defect based upon the image.

Claims

1. A system that is configured to detect a defect in a transparent container, the system comprising:

an emitter that directs light through a sidewall of the transparent container, wherein the light comprises a color gradient such that color of the light across the sidewall of the transparent container varies across the sidewall of the transparent container, and further wherein intensity of the light across the sidewall of the container is approximately uniform across an entirety of the sidewall of the container;

a camera that is configured to capture an image of the sidewall of the transparent container while the light including the color gradient has approximately uniform intensity across the sidewall of the transparent container; and

a computing system that is in communication with the camera, the computing system comprising a processor and memory that stores instructions that, when executed by the processor, cause the processor to perform acts comprising;

detecting a defect in the transparent container based upon the light including the color gradient having approximately uniform intensity across the sidewall of the container as represented in the image; and

outputting an indication that the transparent container includes the defect based upon the image of the sidewall of the container.

2. The system of claim 1, wherein the emitter comprises a first light emitter that emits light of a first color, a second light emitter that emits light of a second color, and a third light emitter that emits light of a third color.

3. The system of claim 2, wherein the first light emitter is a light emitting diode (LED) that emits red light, the second light emitter is an LED that emits green light, and the third light emitter is an LED that emits blue light.

4. The system of claim 2, wherein the emitter comprises a diffusing material positioned between the first light emitter, the second light emitter, and the third light emitter and the transparent container.

5. The system of claim 1, wherein the emitter is a backlight.

6. The system of claim 1, wherein the computing system is configured to detect the defect in the transparent container when the defect is a transparent defect.

7. The system of claim 6, wherein the defect is a blister.

8. The system of claim 1, wherein a conveyor transports the transparent container through an examination region of the system, and wherein the camera is configured to capture the image when the transparent container is in the examination region.

9. The system of claim 1, wherein the computing system is further configured to identify a type of the defect in the transparent container based upon the image, and further wherein the computing system is configured to output an indication of the type of the defect in response to identifying the type of the defect.

10. A method comprising:

emitting, by a backlight, a color gradient, such that the color gradient passes through a sidewall of a transparent container that is under inspection, wherein intensity of the color gradient across the sidewall of the container is approximately uniform across an entirety of the sidewall of the container;

while the intensity of the color gradient is approximately uniform across the entirety of the sidewall of the container, capturing an image of the sidewall of the container;

identifying a defect in the sidewall of the container based upon the color gradient and the intensity of the color gradient being approximately uniform across the entirety of the sidewall of the container as represented in the image; and

responsive to identifying the defect, outputting an indication that the sidewall of the container includes the defect.

11. The method of claim 10, wherein identifying the defect in the sidewall of the container comprises:

generating a gradient image based upon the image of the sidewall of the container;

identifying an edge in the gradient image;

comparing characteristics of the edge in the gradient image to a signature for the defect; and

identifying the defect based upon the comparing of the characteristics of the edge in the gradient image to the signature for the defect.

12. The method of claim 10, wherein the backlight comprises a plurality of light emitting diodes (LEDs), and further wherein the LEDs comprise first LEDs that emit red light, second LEDs that emit blue light, and third LEDs that emit green light.

13. The method of claim 10, wherein the transparent container is tinted.

14. The method of claim 10, further comprising:

identifying a type of the defect from amongst a plurality of possible types, wherein the type of the defect is identified based upon the image of the sidewall of the container.

15. The method of claim 14, wherein the type of the defect is an opaque defect.

16. The method of claim 14, wherein the type of the defect is a transparent defect.

17. The method of claim 10, wherein the container is transported on a conveyor, the method further comprising:

detecting that the container has entered an inspection region;

responsive to detecting that the container has entered the inspection region, capturing the image of the sidewall of the container.

18. The method of claim 10, further comprising:

identifying a second defect in the sidewall of the container based upon the image of the sidewall of the container, wherein the defect is a first type of defect, and wherein the second defect is a second type of defect; and

responsive to identifying the second defect, outputting an indication that the sidewall of the container includes the second defect.

19. A container inspection system that is configured to inspect transparent containers, the container inspection system comprising:

means for directing a color gradient through a sidewall of a transparent container, wherein intensity of the color gradient across the sidewall of the transparent container is approximately uniform across an entirety of the sidewall of the transparent container;

means for generating an image of the sidewall of the container while the color gradient is of approximately uniform intensity across the sidewall of the container; and

a computing system that is configured to receive the image, detect a defect in the sidewall of the container based upon the color gradient being of approximately uniform intensity across the sidewall of the container as represented in the image, and output an indication that the sidewall of the container includes the defect.

20. The transparent container inspection system of claim 19, wherein the means for directing the color gradient comprises:

first light emitting means for emitting light of a first color;

second light emitting means for emitting light of a second color; and

third light emitting means for emitting light of a third color.