Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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NEC Corp
Original Assignee
NEC Corp
Nippon Electric Co Ltd
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Filing date
Publication date
Application filed by NEC Corp, Nippon Electric Co LtdfiledCriticalNEC Corp
Priority to JP14054776ApriorityCriticalpatent/JPS5365750A/en
Publication of JPS5365750ApublicationCriticalpatent/JPS5365750A/en
PURPOSE: To make possible easy measurement of fiber lengths even with fibers of large transmission loss and long fibers by measuring the differential frequency of the input signal frequency and output signal frequency of the fiber to be measured through the use of the frequency-modulated sine wave signal.