Patent · US Expired

Method for inspection of surfaces

US4972493A · kind A · utility

21Cited by
4References
9Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 4, 1988
Grant dateNov 20, 1990
Priority date—
Expiry dateJan 4, 2008

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06T2207/30148
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

An automatic system for the inspection of surfaces of an object employing computer vision. The system examines the uniformity of the surface and adds it to the negative of an ideal mask, and then thresholds the result to determine if the object is defective or not. A binary image showing only the defects is generated by the system. The system ignores surface features, such as locating notches or markings that are intentional, by "fitting" them with their morphological negatives. Small electronic packages, such as integrated circuit plastic packages (e.g. dual-in-line packages or DIPs), can be accurately inspected by the system. The system provides an objective, fast and economical method of inspecting objects.

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