Patent · US Expired

Optical inspection system and method

US6407809B1 · kind B1 · utility

20Cited by
9References
28Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 10, 2000
Grant dateJun 18, 2002
Priority date
Expiry dateFeb 10, 2020

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N2201/0635
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

An optical inspection system is presented, aimed at detecting defects on a substantially flat workpiece having an axis of symmetry. The workpiece is supported on a stage so as to be in an inspection plane, the stage being mounted for rotation in a plane parallel to the inspection plane. A scanning apparatus is accommodated above the workpiece, and comprises an illumination assembly, a plurality of optical assemblies, and a plurality of area sensors. The illumination assembly produces a plurality of incident radiation components for illuminating a strip on the workpiece extending parallel to the axis symmetry between two opposite sides thereof. The optical assemblies are aligned along the axis of symmetry in a spaced-apart parallel relationship, and are mounted for reciprocating movement within a plane parallel to an inspection area that covers substantially a half of the workpiece. The area sensors are arranged in a predetermined manner, each area sensor being associated with a corresponding one of the optical assemblies for receiving a component of returned radiation and generating data representative thereof. The half of the workpiece is strip-by-strip inspected, then the stage w…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.