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Hitachi Ltd
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Hitachi Ltd
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Publication date
Application filed by Hitachi LtdfiledCriticalHitachi Ltd
Priority to JP15056175ApriorityCriticalpatent/JPS5275169A/en
Publication of JPS5275169ApublicationCriticalpatent/JPS5275169A/en
PURPOSE: To reduce the number of assembling process and component parts as well as to shield the electronic beam by omitting both electron shield and electron shield holder.