| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for efficiently inspecting presence/absence of a crack of a penetration hole.SOLUTION: A method comprises: a step S110 for preparing a glass substrate which is an object to be inspected; a step S120 for acquiring images of respective penetration holes of the glass substrate; a step S130 for calculating an apparent diameter D of each penetration hole; a step S140 for creating a frequency distribution indicating a relationship between the apparent diameter D and frequency I, drawing a horizontal line L1 indicating predetermined frequency Ion the frequency distribution, then determining the diameter D closest to a maximum frequency value Dand larger than the maximum frequency value Din which maximum frequency Iis acquired, as a threshold D, of cross points between the horizontal line L1 and the frequency distribution, in which the predetermined frequency Iis selected from a range of 0.01-0.1% of the maximum frequency I; and a step S150 for selecting the respective penetration holes whose diameter D is equal to or more than the threshold Das penetration holes which are objects to be inspected, and evaluating presence/absence of a crack on the penetration holes which are the object to be inspected.SELECTED DRAWING: Figure 1 |
