MANUFACTURING METHOD FOR ROD LENS AND THE ROD LENS

摘要

PROBLEM TO BE SOLVED: To provide a manufacturing method for a rod lens which can precisely control a refractive index distribution and to provide the rod lens which has low loss, low wavelength dispersion, and low mode dispersion. SOLUTION: A rod lens base material 1 is manufactured by a PCVD method and drawn to a desired external diameter to manufacture a base material 2 having been drawn. Then cut pieces 3 are manufactured by cutting the drawn base material to desired length and end surfaces are polished to manufacture rod lenses 4. The rod lens base material 1 is so manufactured that one layer formed by the PCVD method decreases in thickness toward the center of the rod lens base material and the precision of the refractive index distribution of the rod lens is further improved.