| 摘要 |
In a pattern testing device, a pattern (50) to be tested is scanned by a photoelectric transducer (51). The electrical output signals of the transducer are split by a splitting circuit (52) into picture element signals which are processed further as binary coded output signals. Several window areas can be set within the field of vision of the photoelectric transducer (51). The binary output signals are used as a basis for the measurement of particular feature variables of the pattern to be tested in each window area. A primary decision circuit (56) decides that the pattern is good in a window area when the relevant feature variable is within a predetermined threshold range. Otherwise, the pattern in this area is poor. A secondary decision circuit (57) compares the results of the primary decision with a table formed in advance in order to make a go/no-go decision. If necessary, a correlation with subsequent correlation decisions is carried out in a primary correlation decision circuit (61) and a secondary correlation decision circuit (62), using the feature variables of adjacent window areas. <IMAGE>
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