Patent · US Expired

Pinhole inspection device and method

US5555315A · kind A · utility

10Cited by
11References
16Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 2, 1994
Grant dateSep 10, 1996
Priority date
Expiry dateFeb 2, 2014

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06T2207/30164
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

An inspection device and method that closely approximates a visual inspection technique for evaluating the quality of a sample. A mask image generation section generates a master image from an image signal of a known good sample. The image signal is used to a first mask image. A plurality of second mask images are generated by magnifying a pattern area of the first mask image by different magnification ratios. A discrimination surface area threshold is set for each mask image. An image under inspection generation section generates a binary image of an unknown sample. A discrimination section takes the logical AND of the binary images of the unknown sample and each mask image, calculates surface areas of pinhole flaws existing in a background area of the binary image under inspection, compares the calculated surface areas and the threshold corresponding to the mask images, and performs a pass/fail judgement of the unknown sample based on the result of this comparison.

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