OPTICAL PARTS, OPTICAL MODULE, OPTICAL AMPLIFIER AND OPTICAL COMMUNICATION SYSTEM

摘要

PROBLEM TO BE SOLVED: To provide an optical part which has an optical waveguide type diffrac tion grating element in which a grating is formed on the optical waveguide is formed and with which parts a fine adjustment of a reflection spectrum or a loss spectrum is easily performed. SOLUTION: A compressive stress or a tensile stress is given to the optical waveguide type diffraction grating element 160 fixed on a flexible member 150 as a result of the deflection of the flexible member 150 due to the action of solenoids 120 and 130. The grating cycle is varied by the stress and the optical characteristic (reflection spectrum or loss spectrum) of the optical waveguide type diffraction grating element 160 is varied.