Camera and method for detecting object moving relative to the camera

Patent metadata

Field	Value
Publication number	US-2018288317-A1
Application number	US-201815937344-A
Country	US
Kind code	A1
Filing date	Mar 27, 2018
Priority date	Mar 30, 2017
Publication date	Oct 4, 2018
Grant date	—

Abstract

A camera (10) for detecting objects (32) moving relative to the camera (10) in a conveying direction (34), comprising a light receiver (20) having a plurality of pixels (24) arranged in two lines (22a-b) in a line direction transverse to the conveying direction (34) and an evaluation unit (26) configured to generate a first and second image (40a-b) of a partial region of the object (32) by means of the two lines (22a-b), the images (40a-b) having a mutual offset in the line direction, to compute an image line of higher resolution than an original resolution from the first and second image (40a-b), and to compose an overall image from the image lines generated in the course of the movement, wherein reception optics (16) are arranged in front of the light receiver (20) for providing the mutual offset.

First claim

1 . A camera ( 10 ) for detecting objects ( 32 ) moving relative to the camera ( 10 ) in a conveying direction ( 34 ), the camera ( 10 ) comprising
a light receiver ( 20 ) having a plurality of light receiving pixels ( 24 ) arranged in at least two lines ( 22 a - b ) in a line direction transverse to the conveying direction ( 34 ) and a control and evaluation unit ( 26 ) configured to generate a first image ( 40 a ) and a second image ( 40 b ) of a partial region of the object ( 32 ) by means of the two lines ( 22 a - b ), the images ( 40 a - b ) having a mutual offset at least in the line direction, to compute an image line of higher resolution than an original resolution of the light receiver ( 20 ) from the first image ( 40 a ) and the second image ( 40 b ), and to compose an overall image from the image lines generated in the course of the movement of the objects ( 32 ), wherein reception optics ( 16 ) are arranged in front of the light receiver ( 20 ) for providing the mutual offset between the first image ( 40 a ) and the second image ( 40 b ).

2 . The camera ( 10 ) according to claim 1 ,
wherein the light receiving pixels ( 24 ) are arranged in a mutual pixel distance, and wherein the offset of the images ( 40 a - b ) corresponds to a fraction of the pixel distance.

3 . The camera ( 10 ) according to claim 1 ,
wherein the control and evaluation unit ( 26 ) is configured to generate the first image ( 40 a ) and the second image ( 40 b ) with an offset also transverse to the line direction, and to generate an overall image of higher resolution than the original resolution also in the conveying direction ( 34 ).

4 . The camera ( 10 ) according to claim 3 ,
wherein the reception optics ( 16 ) also provide the offset in the conveying direction ( 34 ).

5 . The camera ( 10 ) according to claim 3 ,
wherein the control and evaluation unit ( 26 ) is configured to generate the first image ( 40 a ) and the second image ( 40 b ) with staggered exposure time windows.

6 . The camera ( 10 ) according to claim 1 ,
wherein the reception optics ( 16 ) comprise a plurality of microlenses ( 18 ) which are, in the line direction, at least one of tilted or offset relative to a grid of the light receiving pixels ( 24 ).

7 . The camera ( 10 ) according to claim 6 ,
wherein the microlenses ( 18 ) for the one line ( 22 a - b ) are tilted or offset in a direction opposite to the microlenses ( 18 ) for the other line ( 22 b - a ).

8 . The camera ( 10 ) according to claim 1 ,
wherein the reception optics ( 16 ) comprise a plurality of microlenses ( 18 ) which are, in the conveying direction ( 34 ), at least one of tilted or offset relative to a grid of the light receiving pixels ( 24 ).

9 . The camera ( 10 ) according to claim 8 ,
wherein the microlenses ( 18 ) for the one line ( 22 a - b ) are tilted or offset in a direction opposite to the microlenses ( 18 ) for the other line ( 22 b - a ).

10 . The camera ( 10 ) according to claim 1 ,
wherein the reception optics ( 16 ) comprise a diffractive optical element.

11 . The camera ( 10 ) according to claim 1 ,
wherein the reception optics ( 16 ) comprise at least one free-form surface ( 46 ).

12 . The camera ( 10 ) according to claim 1 ,
wherein the reception optics ( 16 ) comprise at least one tilted or wedge-shaped surface ( 44 ).

13 . The camera ( 10 ) according to claim 1 ,
wherein the reception optics ( 16 ) have different color filters for the lines ( 22 a - b ).

14 . A method for detecting objects ( 32 ) by a light receiver ( 20 ) of a camera ( 10 ), the objects ( 32 ) moving relative to the camera ( 10 ) in a conveying direction ( 34 ) and the light receiver ( 20 ) comprising a plurality of light receiving pixels ( 24 ) arranged in at least two lines ( 22 a - b ) in a line direction transverse to the conveying direction ( 34 ),
wherein a first image ( 40 a ) and a second image ( 40 b ) of a partial region of the object ( 32 ) are generated by means of the two lines ( 22 a - b ), the images ( 40 a - b ) having a mutual offset at least in the line direction, wherein an image line having a higher resolution than an original resolution of the light receiver ( 20 ) is computed from the first image ( 40 a ) and the second image ( 40 b ) and an overall image is composed from the image lines generated in the course of the movement of the objects ( 32 ), and wherein the mutual offset between the first image ( 40 a ) and the second image ( 40 b ) is provided by reception optics ( 16 ) arranged in front of the light receiver ( 20 ).

Assignees

• Sick Ag

Inventors

• Nopper Richard
• Strohmeier Dirk

Classifications

• H04N23/55 Primary

  Optical parts specially adapted for electronic image sensors; Mounting thereof · CPC title

• H04N23/951

  by using two or more images to influence resolution, frame rate or aspect ratio · CPC title

• H04N23/12

  with one sensor only · CPC title

• H04N25/701

  Line sensors · CPC title

• H04N25/48

  Increasing resolution by shifting the sensor relative to the scene · CPC title