| 摘要 |
PURPOSE:To enable the execution of the phase adjustment of exit signal light and the adjustment of a so-called operating point without using a DC electric field for control by delicately changing the refractive index of an optical waveguide by the strain generated in the waveguide. CONSTITUTION:The optical waveguide 2 is so formed in the prescribed part of a substrate 1 having a surface parallel with a direction X so as to have a thickness in a direction Z, This waveguide 2 is formed of a ferroelectric material having a photoelastic effect and is formed by diffusing, for example, titanium into Z-cut LiNbO3. A material different from the material forming the optical waveguide, for example, SiO2, is deposited on the substrate 1 having the optical waveguide 2, by which a deposited film layer 3 is formed. The internal stress is generated in this deposited film layer 3 and the laminate obtd. by this internal stress is warped and deformed to an arc shape. The strain parallel with the axial direction of the optical waveguide 2, i.e., the direction X, is generated in the optical waveguide by this warpage and deformation. The adjustment of the operating point of the optical element chip is executed by adjusting the strain quantity of the optical waveguide 2 to adjust the delay of the phase. |
