Identification apparatus, identification system, and resin-selecting system

Patent metadata

Field	Value
Publication number	US-11099073-B2
Application number	US-202016892017-A
Country	US
Kind code	B2
Filing date	Jun 3, 2020
Priority date	Dec 5, 2017
Publication date	Aug 24, 2021
Grant date	Aug 24, 2021

Abstract

An identification apparatus identifies the kind of an object to be conveyed by a conveyor and includes an illumination optical system illuminating the object with light from a light source, a light capturing optical system capturing Raman-scattered light from the object, a spectral element dispersing the Raman-scattered light, a light-receiving element receiving the Raman-scattered light dispersed by the spectral element, and a data-processing unit acquiring spectral data of the Raman-scattered light from the light-receiving element and performs an identification process. An optical axis of the illumination optical system and an optical axis of the light capturing optical system intersect each other. The illumination optical system is an imaging optical system that has a numerical aperture for the conveyance surface smaller than that of the light capturing optical system for the conveyance surface, or a collimator optical system that converts the light from the light source into parallel light.

First claim

What is claimed is:

1. An identification apparatus that identifies a kind of resin that is contained in an object to be conveyed by a conveyor, the identification apparatus comprising:
an illumination optical system that illuminates the object on a conveyance surface of the conveyor with light from a light source;
a light capturing optical system that captures Raman-scattered light from the object that is illuminated by the illumination optical system;
a spectral element that disperses the Raman-scattered light that is captured by the light capturing optical system;
a light-receiving element that receives the Raman-scattered light that is dispersed by the spectral element; and
a data-processing unit that acquires spectral data of the Raman-scattered light from the light-receiving element and that performs a process of identifying the object, based on the spectral data,
wherein an optical axis of the illumination optical system and an optical axis of the light capturing optical system intersect each other, and
wherein the illumination optical system is an imaging optical system that has a numerical aperture for the conveyance surface smaller than a numerical aperture of the light capturing optical system for the conveyance surface.

2. The identification apparatus according to claim 1 , further comprising:
an optical fiber that guides the Raman-scattered light that is captured by the light capturing optical system to the spectral element.

3. The identification apparatus according to claim 2 ,
wherein the numerical aperture of the light capturing optical system for the conveyance surface is larger than a numerical aperture of the light capturing optical system for the optical fiber.

4. The identification apparatus according to claim 3 ,
wherein the numerical aperture of the light capturing optical system for the optical fiber is smaller than a numerical aperture of an entrance end of the optical fiber.

5. The identification apparatus according to claim 1 ,
wherein an angle that is formed between a conveyance direction of the conveyor and a plane containing the optical axis of the illumination optical system and the optical axis of the light capturing optical system is no less than 0 degrees and no more than 15 degrees.

6. The identification apparatus according to claim 1 ,
wherein a plane containing the optical axis of the illumination optical system and the optical axis of the light capturing optical system is parallel to a conveyance direction of the conveyor.

7. The identification apparatus according to claim 1 ,
wherein an angle that is formed between the optical axis of the illumination optical system and the conveyance surface differs from an angle that is formed between the optical axis of the light capturing optical system and the conveyance surface.

8. The identification apparatus according to claim 1 ,
wherein the light capturing optical system includes a wavelength filter that shields light having at least a wavelength range in the light and allows the Raman-scattered light to pass therethrough, and
wherein the wavelength filter is disposed on a pupil surface of the light capturing optical system.

9. The identification apparatus according to claim 1 ,
wherein the illumination optical system defines an illumination region on the conveyance surface, and
wherein a width of the illumination region in a conveyance direction of the conveyor is greater than a width of the illumination region in a direction perpendicular to the conveyance direction of the conveyor.

10. The identification apparatus according to claim 1 ,
wherein the illumination optical system is a collimator optical system that converts the light from the light source into parallel light.

11. The identification apparatus according to claim 1 ,
wherein the light-receiving element is an area image sensor that includes photoelectric conversion elements that are two-dimensionally arranged.

12. The identification apparatus according to claim 1 ,
wherein the object is a crushed object.

13. An identification system comprising:
the identification apparatus according to claim 1 ; and
the conveyor.

14. A selection system comprising:
the identification apparatus according to claim 1 ;
the conveyor; and
a selection unit that is disposed nearer than the identification apparatus to a downstream side of the conveyor and that selects the object, based on an identification result of the identification apparatus.

15. An identification apparatus that identifies a kind of resin that is contained in an object to be conveyed by a conveyor, the identification apparatus comprising:
capturing units each of which includes an illumination optical system that illuminates the object on a conveyance surface of the conveyor with light from a light source, and a light capturing optical system that captures Raman-scattered light from the object that is illuminated by the illumination optical system, the capturing units facing the conveyance surface of the conveyor and being arranged at different positions in a traverse direction of conveyance intersecting a conveyance direction of the conveyor;
an optical fiber bundle that includes optical fibers that guide the Raman-scattered light that is captured by the capturing units, the optical fibers being bundled near an exit end of the optical fiber bundle;
a spectral element that disperses a collection of the Raman-scattered light that is guided by the optical fiber bundle;
a light-receiving element that receives the collection of the Raman-scattered light that is dispersed by the spectral element; and
a data-processing unit that acquires spectral data of the collection of the Raman-scattered light from the light-receiving element and that performs an identification process,
wherein in each of the capturing units, an optical axis of the illumination optical system and an optical axis of the light capturing optical system intersect each other.

16. The identification apparatus according to claim 15 ,
wherein in each of the capturing units, the illumination optical system is an imaging optical system that has a numerical aperture for the conveyance surface smaller than a numerical aperture of the light capturing optical system for the conveyance surface.

17. The identification apparatus according to claim 15 ,
wherein the illumination optical system is a collimator optical system that converts the light from the light source into parallel light.

18. The identification apparatus according to claim 15 ,
wherein exit ends of the optical fibers are arranged in a line in the traverse direction of conveyance.

19. The identification apparatus according to claim 15 ,
wherein the capturing units are arranged at different positions in the traverse direction of conveyance.

20. The identification apparatus according to claim 15 ,
wherein the capturing units are arranged at different positions in the conveyance direction.

21. The identification apparatus according to claim 15 ,
wherein the capturing units partly overlap when viewed in the traverse direction of conveyance.

22. The identification apparatus according to claim 15 ,
wherein in each of the capturing units, an angle that is formed between the conveyance direction of the conveyor and a plane containing the optical axis of the illumination optical system and the optical axis of the light capturing optical system is no less than 0 degrees and no more than 15 degrees.

Assignees

• Canon Kk

Inventors

• Yonetani Yuki
• Ichihara Shigeru
• Sekine Yasuhiro
• Yamamoto Akira

Classifications

• G01N21/65

  Raman scattering · CPC title

• G01J3/44 Primary

  Raman spectrometry; Scattering spectrometry {; Fluorescence spectrometry} · CPC title

• B29B17/00

  Recovery of plastics or other constituents of waste material containing plastics; ({volume reduction of waste plastics, e.g. by mechanical compacting or melting disposal of solid waste B09B;} chemical recovery C08J11/00) · CPC title

• G01N2021/845

  Objects on a conveyor · CPC title

• G01J3/0218

  using optical fibers · CPC title