Method and inspection apparatus for inspecting an object, in particular a bottle

摘要

A method of and apparatus for inspecting an object, in particular a bottle, which is irradiated by a radiation that is received and converted into an electrical videosignal which is converted into a digital signal, points of fault in the object being established by alterations in intensity between the digital signals from two adjacent image spots, characterized in that: (1) only alterations in intensity which exceed a definite threshold level are recorded as the start of a point of fault and the end of a point of fault; (2) for each of these points of fault certain characteristic quantities such, e.g., as mean relative blackening, maximum relative blackening, width of the point of fault and/or overall extent of the point of fault, are determined; (3) the characteristic quantities are divided up into different classes corresponding with their magnitudes; (4) the frequency distribution of the occurrence of the characteristic quantities in the different classes is established by adding; and (5) the frequency distribution established is correlated with predetermined frequency distributions in order to decide about the quality of the object.