| 摘要 |
PROBLEM TO BE SOLVED: To make obtainable an excellent filter characteristic, by reducing a side robe occurring when incident light is mode-converted when wavelength multiplexed signal light is divided, and a noise light component in the signal light is removed. SOLUTION: This device is constituted so that an optical waveguide 2 is formed on a substrate 1 having an electrooptic effect, and a pair of electrode parts 4, 5 so as to apply a periodical electric field over the prescribed range of the optical waveguide 2 is formed on it, and light of a required wavelength is mode-converted according to the characteristic of the electric field applied by a pair of electrode parts 4, 5 to be emitted. In such a case, a periodical electric field intensity applied to an optical waveguide position in the vicinity of the ends of a pair of electrode parts 4, 5 becomes smaller than the periodical electric field intensity applied to the optical waveguide position in the vicinity of the central parts of a pair of electrode parts 4, 5. |
