Patent · US Expired

Optical inspection method and apparatus

US6175645A · kind A · utility

107Cited by
7References
55Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 22, 1998
Grant dateJan 16, 2001
Priority date
Expiry dateJan 22, 2018

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N21/8806
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A method and an apparatus for an optical inspection of an object, having upper and lower faces, so as to detect defects existing on the object. First and second beams of an incident radiation are produced and directed onto the object. A light component of the first incident beam, which is reflected from one face of the object, and a light component of the second incident beam, which is transmitted through the upper and lower faces of the object, are simultaneously sensed. First and second images, formed, respectively by reflected and transmitted light components are acquired and analyzed so as to provide data indicative of the defects.

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