Dynamic lighting system for specular surface inspection

Ralph Seulin; Fred Merienne; Patrick Gorria

doi:10.1117/12.420913

4 April 2001 Dynamic lighting system for specular surface inspection

Ralph Seulin, Fred Merienne, Patrick Gorria

Proceedings Volume 4301, Machine Vision Applications in Industrial Inspection IX; (2001) https://doi.org/10.1117/12.420913
Event: Photonics West 2001 - Electronic Imaging, 2001, San Jose, CA, United States

Abstract

Specular surfaces inspection is a problem met frequently within the automatic control of metallic products. A tried technique to reveal the aspect defects is the imaging of the reflection of a structured lighting as Dark Field Illumination through the surface. In order to inspect the whole surface, an element of the lighting structure has to scan every part of the surface. In the case of important surface curvature gradients, entire scanning is not ensured if the object is moving in front of the static lighting. To overcome this limitation, an inverse process is proposed: the lighting structure is dynamic while the object is static. The scanning of the surface by the various lighting configurations enables the aspect control. A modeling of the surface to be inspected and defects to be detected is made. Inverse ray tracing is used to analyze the reflection of the lighting through the surface. This modeling enables to ensure the revealing of defects by respecting the chosen criteria of detection. A relation binding the physical size of defects and its size on the image is established. A metrological approach of the problem is then performed.

Citation Download Citation

Ralph Seulin, Fred Merienne, and Patrick Gorria "Dynamic lighting system for specular surface inspection", Proc. SPIE 4301, Machine Vision Applications in Industrial Inspection IX, (4 April 2001); https://doi.org/10.1117/12.420913

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available