| 摘要 |
PROBLEM TO BE SOLVED: To provide a manufacturing method of a grating that enables reduction of a ripple width in transmission characteristics of a grating.SOLUTION: A manufacturing method of a grating includes the steps of: disposing cylindrical lenses 31 and an optical fiber 2 so that the optical fiber 2 is present closer to a cylindrical lens 31 side than a back focal position of the cylindrical lenses 31 and also disposing a phase mask 41 between the cylindrical lenses 31 and the optical fiber 2; and then irradiating the optical fiber 2 with a laser beam emitted from a laser light source 11 via the cylindrical lenses 31 and the phase mask 41 and writing a grating in the optical fiber 2. |
