Distribution coupling type period branching filter

Abstract

Abstract PURPOSE:To provide the distribution coupling type period branching filter of low losses which do not produce any characteristic degradation owing to aging by so working two eccentric core optical fibers that when their worked faces are mated they assume a nearly circular section then fusion bonding the same. CONSTITUTION:The side faces of a large thickness of the clad parts 41, 42 of optical fibers in which the centers of cores 31, 32 deviate from the centers of the optical fibers are worked flat over the specified length, whereby their sectional shapes are made nearly semicircular. These are so formed that the sectional shape 4' obtained by mutually fusion bonding the flat parts of the semicircular optical fibers in which the sectional shapes of the two fibers are nearly semicircular is nearly circular in which the two cores 31', 32' are contained. Hence, the change in the sectional shape after the fusion bonding is less and the deformation of the cores is slight and therefore the losses are low and the characteristic change owing to aging does not occur.

Inventors

• 👤 Takao Itanami
• 👤 Nobuo Nakajima
• 👤 Tadashi Takano
• 👤 Takaichi Watanabe

Bibliographic Details