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Hitachi Ltd
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Hitachi Ltd
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Application filed by Hitachi LtdfiledCriticalHitachi Ltd
Priority to JP3554375ApriorityCriticalpatent/JPS51111350A/en
Publication of JPS51111350ApublicationCriticalpatent/JPS51111350A/en
PURPOSE: To raise the surveying speed of a surface-defect detecting device for paterns of the semiconductor element etc., without increasing the clock frequency.