Patent · US Expired

Inspection apparatus

US4172666A · kind A · utility

18Cited by
3References
3Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 21, 1977
Grant dateOct 30, 1979
Priority date
Expiry dateNov 21, 1997

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N21/89
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

To distinguish between different types of fault detected by laser scanning of a moving web two or more detectors are arranged to collect light reflected in different ranges of angles in direction of web motion. By combining outputs of these in a logical way representing increases or decreases in the sums and differences of the signals they produce, the faults can be classified as absorbing, scattering, or their opposites, or deflecting.

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