| 摘要 |
PURPOSE:To obtain the title parent material useful in continuous optical fibers for communication, having low optical loss and excellent maintenance of polarization, by forming a specific soot around the core rod by controlling the feed rates of starting gases. CONSTITUTION:A clad core rod of about 10phi is rotated at a rate of about 10rpm. A 4-layer structure burner 4 for forming the first clad is used to feed SiCl4 together with Ar carrier through the first layer, H2 through the second layer, Ar through the third layer, and O2 through the fourth layer around the rod 1 to effect flame hydrolysis and form soot 2. Then, the gas feed rates are controlled, while the rod rotates 1 round, so that the bulk density distributes in an elliptic form in the peripheral direction. Then, glass starting gases different from the buffer 4 are fed from the burner 5 to deposits soot 3 on the soot 2 to obtain soots 2, 3 of about 80phi. Then the soots 2, 3 are dehydroxylated and glassified to give a parent material of an elliptic cross section for an optical fiber for polarized beams. |
