PURPOSE: To manufacture an optical fiber retaining the plane of polarization and having different constants of optical transmission in accordance with the axial directions, by putting a quartz pipe of small diameter having a core part in the center of a quartz pipe of large diameter having a jacket part, making the pipes solid by heating, and drawing the resulting solid pipe.
CONSTITUTION: A quartz glass layer 2 having a slightly higher refractive index than a quartz pipe 1 of large diameter is formed as a jacket part on the inner wall of the pipe 1 by an MCVD method. A core part 5 made of a quartz glass layer having a high refractive index is formed on the inside of a quartz pipe 4 of small diameter for a clad part by said MCVD method, and the pipe 4 is put in the pipe 1 while leaving space 3. The pipes 1, 4 are made solid by slow heating from one side while controlling the atmospheric pressure in the space 3 between the pipes 4, 1 and that in the space 6 in the pipe 4 so as to make the cross section of the jacket 2 or the core elliptical, and the resulting solid pipe is drawn to manufacture on optical fiber retaining the plane of polarization and having different constants of optical transmission in accordance with the axial directions.
TOKUNAGA TOSHIHIDE
KAJIOKA HIROSHI
