Dual level out-of-focus light source for amplification of...

Radiant energy – Photocells; circuits and apparatus – With circuit for evaluating a web – strand – strip – or sheet

Reexamination Certificate

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

C250S559400, C356S237100, C356S239100

Reexamination Certificate

active

07105848

ABSTRACT:
A web defect inspection system includes line scan cameras positioned across the width of a web and a dual-level out-of-focus light source for illuminating the web. An illumination surface of the dual-level light source has a bright portion adjacent a dark portion. One such dual-level light source is provided by covering a portion of a diffused light surface with an opaque material having a sharp edge. The pixels of each line scan camera are aligned with the dark to light transition of the light source so that each pixel has a no-defect brightness level equal to half of a relative brightness level of the bright portion of the dual-level light source. An image of a defect-free portion of the web consists of pixels having relative brightness levels within a pre-determined range of the no-defect brightness level. Images of defects on the web surface appear three-dimensional as bright and dark areas. The nature of the defect, that is, whether the defect is concave or convex, is determined based upon the orientation of the dual-level light source and the direction of movement of the web.

REFERENCES:
patent: 4606634 (1986-08-01), Bieringer
patent: 5132791 (1992-07-01), Wertz et al.
patent: 5274243 (1993-12-01), Hochgraf
patent: 5402228 (1995-03-01), Jordan et al.
patent: 5416594 (1995-05-01), Gross et al.
patent: 5471298 (1995-11-01), Moriya
patent: 5526119 (1996-06-01), Blit et al.
patent: 5544256 (1996-08-01), Brecher et al.
patent: 5684530 (1997-11-01), White
patent: 5742398 (1998-04-01), Laucoumet
patent: 5764874 (1998-06-01), White
patent: 5790247 (1998-08-01), Henley et al.
patent: 5835207 (1998-11-01), Sugiura et al.
patent: 5870204 (1999-02-01), Chiu et al.
patent: 6166393 (2000-12-01), Paul et al.
patent: 6297879 (2001-10-01), Yang et al.
patent: 6433867 (2002-08-01), Esquivel

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Dual level out-of-focus light source for amplification of... does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Dual level out-of-focus light source for amplification of..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Dual level out-of-focus light source for amplification of... will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-3526600

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.