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Hitachi Ltd
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Hitachi Ltd
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Application filed by Hitachi LtdfiledCriticalHitachi Ltd
Priority to JP13404776ApriorityCriticalpatent/JPS5359453A/en
Publication of JPS5359453ApublicationCriticalpatent/JPS5359453A/en
PURPOSE: To perform the measurement of movement amounts of less errors by limiting the counting of a counter owing to the vibration of a moving stage in an apparatus of neasuring the movement amounts through the interference of laser light.