Patent · US Expired

Method and apparatus for appearance inspection

US4410278A · kind A · utility

44Cited by
4References
15Claims
0Family size

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Inventors

Key dates

Filing dateJul 18, 1980
Grant dateOct 18, 1983
Priority date
Expiry dateJul 18, 2000

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N21/952
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

An apparatus for inspecting the outer peripheral surface of a cylindrical object is disclosed, in which the light in slit form is radiated on the surface of an object such as a nuclear fuel pellet at an angle thereto, the light regularly reflected on the surface is detected by a detector, the detected image signal is quantized at threshold values higher and lower than an average level, and the binary signals are used to detect surface losses separately from an unground part and a metal inclusion as a first detection process. The diffused light is radiated onto the surface of the nuclear fuel pellet at an angle thereto, parallel light rays are radiated onto the surface from the direction perpendicular thereto, the light reflected from the surface of the object is detected by a detector from the direction perpendicular to the surface, the detected image signal is quantized at a threshold level lower than an average level of the image signal for the normal surface, and the binary signal is used to detect, as a second detection process, a crack and a pit separately from a chip, said crack, pit or chip included in surface missing defects detected in said first detection process. The sur…

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