PURPOSE: To obtain an end face having good accuracy without deformation during polishing by subjecting a plastic fiber to a heat treatment at the glass transition temp. of the plastic constituting the core of said fiber or above then polishing the end face in the terminal part of the fiber.
CONSTITUTION: The cut terminal part of a plastic fiber of which a core material 1 consists of PMMA and a clad 2 consists of a copolymer of vinylidene fluoride and tetrafluoroethylene is heat-treated for 30 seconds at 120°C and thereafter the terminal part of the plastic fiber is so fixed as to project the cut face 3 in the terminal part of the plastic fiber by about 0.5mm from the end face of a polishing jig 4. The projecting face 3 of the plastic fiber is then brought into contant with the surface of an abrasive material under rotation, by which said face is polished. The scattering loss at the end face of the plastic fiber formed freshly by the polishing is 0W0.2dB.
NISHIKAWA MITSURU
UEHA YOSHINOBU
