The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 12, 1989
Filed:
Aug. 15, 1986
Klaus Weber, Konigsbronn, DE;
Erwin Sick GmbH Optik-Elektronik, Waldkirch, DE;
Abstract
The sharply bounded entry pupil (13) of an optical web monitoring apparatus is imaged by the system after passage through or reflection at the material web onto a dark field stop (16). This stop is provided at its periphery with light receiving surfaces having a relatively small area relative to the extent of the dark field stop (16). These light receiving surfaces conduct the received light to a photoconverter arrangement which is connected to an electronic processing circuit. In this way material faults are detected which bring about only small angular deviations of the scanning beam. In order to detect faults with greater light scattering a multiplier (23) is additionally mounted behind this receiver arrangement and receives light deflected beyond the light receiving surfaces.