| 摘要 |
PURPOSE:To uniformize the amt. of fine glass grains to be deposited in the longitudinal direction of target member by traversing a fine glass grain generator at a specified speed in the longitudinal direction of the rotating target member. CONSTITUTION:The both ends of the target member 1 such as a glass rod are held by the chuck of a glass lathe, etc., and the member 1 is rotated on its center axis as a rotary shaft. A soot burner 2 is traversed in the longitudinal direction of the rotating member 1, and soot is deposited around the member 1 to form a columnar soot deposit 3. In this case, the traversing speed is reduced at the section between E and G on both ends of the traverse length A, hence the deposition amt. is increased at the part, the deficiency in the deposition amt. on both ends is supplied. The fluctuation in the outer diameter of the external deposit 3 is controlled in this way, and soot is uniformly deposited with high precision. As a result, when the deposit 3 is sintered, vitrified, spun and thinned to obtain an optical fiber, the cutoff wavelength of the optical fiber is uniformized in the longitudinal direction with high precision. |
