Patent · US Expired

Inspection method using area of interest (AOI) analysis

US5369713A · kind A · utility

48Cited by
9References
4Claims
0Family size

Inventors

Key dates

Filing dateJun 28, 1993
Grant dateNov 29, 1994
Priority date
Expiry dateJun 28, 2013

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N21/9027
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A technique for detecting defects in stationary products or in products moving on a production line (102, FIG. 1) by analyzing area of interest (AOls) of their modified images uses a matrix or linescan camera (104, FIG. 1) for taking images of products (102). The product's dimensions are measured with accuracy, and the existence and alignment of caps and seals is determined. The technique is much faster and more accurate than current techniques and is based up on an analysis of the AOls and their discontinuities. (209 FIG. 1). Carefully selected AOls of the modified image (2 to 8, FIG. 2) are saved in the memory of a computer (106, FIG. 1). The method also includes loading look-up tables to modify the gray levels of the products; saving AOls in memory to be analyzed (FIG. 1); analyzing AOl data, counting pixel discontinuities, etc. The results can be used to measure product ovality, check caps and seals on products, and check changes of fluid or content levels in containers.

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