| 摘要 |
PURPOSE:To improve reflectivity by laminating a dummy layer on a waveguide near the end face of the waveguide to be optically coupled to a semiconductor laser, then depositing an antireflection film on the end face of the above- mentioned waveguide. CONSTITUTION:The dummy layer 6 consisting of, the example, SiO2 is laminated by an EB vapor deposition method or sputtering method on the waveguide 3 at the end face to be optically coupled to the semiconductor laser in the state of disposing a shielding plate 5 on a grating 4. The side end part to be optically coupled to the semiconductor laser is then removed and flatted by cleavage or cutting and polishing. The antireflection film 7 consisting of, for example, MgF2 is thereafter deposited by an EB vapor deposition method on the end face of the waveguide 3. Finally, the semiconductor laser 8 is disposed to the end face of the waveguide 3 and is optically coupled to the waveguide 3. The reflectivity of the end face is 0.0243% according to a theoretical calculation and is greatly improved as compared to 9.93% reflectivity in case of not forming the antireflection film 7. |
