Title:
SYSTEM AND METHOD FOR DETECTING DEFECT ON SPECULAR SURFACE WITH VISION SYSTEM
Document Type and Number:
Japanese Patent JP2017111121
Kind Code:
A
Abstract:
PROBLEM TO BE SOLVED: To provide a system and method for detecting a specular surface defect on a specular surface using a knife edge technique, and photographing the specular surface defect thereon.SOLUTION: A camera aperture or external device is set so as to form a physical knife edge structure in an optical path. The knife edge structure is configured to effectively block a reflected light ray from an illuminated specular surface of a predetermined inclination degree and allow the light ray deflected with a different inclination to reach an image sensor S of a vision system camera 120. Light reflected from a flat portion of a surface is almost blocked by a knife edge. Light reflected from an inclination part of a defect is mostly reflected into an incident aperture. An illumination beam is inclined with respect to an optical axis of a camera to provide an appropriate angle of incidence with respect to the surface under examination. The surface may be stationary or move relatively move with respect to the camera.SELECTED DRAWING: Figure 1
Inventors:
FARIBORZ ROSTAMI
JOHN F FILHABER
QIAN FENG
JOHN F FILHABER
QIAN FENG
Application Number:
JP2016221074A
Publication Date:
June 22, 2017
Filing Date:
November 12, 2016
Export Citation:
Assignee:
COGNEX CORP
International Classes:
G01B11/30; G01N21/89; G01N21/896
Domestic Patent References:
| JP2009092426A | 2009-04-30 | |||
| JPH03115844A | 1991-05-16 | |||
| JPS61176805A | 1986-08-08 |
Attorney, Agent or Firm:
Hiroyuki Kurihara