| 摘要 |
PROBLEM TO BE SOLVED: To rapidly manufacture plural gratings, compact and low in loss. SOLUTION: Phase grating plates 21, 22 and 23 are arranged around an optical fiber 10 of a quartz system added with a Ge (germanium) element in its at least core region 11. Irradiation light rays A1, A2 and A3 are respectively made incident on these phase grating plates 21, 22 and 23 to form interference fringes along the optical axis direction of the optical fiber 10, to form the plural gratings simultaneously. |
