Pg. Zhang et D. Irvinehalliday, MEASUREMENT OF THE BEAT LENGTH IN HIGH-BIREFRINGENT OPTICAL-FIBER BY WAY OF MAGNETOOPTIC MODULATION, Journal of lightwave technology, 12(4), 1994, pp. 597-602
One of the most important parameters about high-birefringent optical f
iber is the beat length. Because of its shortness and periodicity, the
measurement of the beat length is very critical. Here, a highly accur
ate measurement method that relies on magnetooptic modulation techniqu
es is proposed, and the theoretical analysis and discussion about the
measurement theories and the instrument construction are given in deta
il. Finally, the construction of the beat length measurement instrumen
t based on this novel method is described and several kinds of high-bi
refringent optical fiber samples are measured. The beat-length resolut
ion of this instrument is better than 0.01 mm, and the final measuring
results are not influenced by the external interference on the fiber
or the status of the placement of the optical fiber.