| 摘要 |
PROBLEM TO BE SOLVED: To provide a light transmission device with a large optical output, suitable for a high speed and a large capacity optical transmission system also excellent in an antireflection characteristic. SOLUTION: This light transmission device has a waveguide-type optical element emitting light, a light transmission path optically coupled to this waveguide-type optical device, and a waveguide-type optical element is composed of a light-emitting part having at least partly in it a gain coupling type diffraction grating 54, and a mode converting region integral therewith. In such a manner, it is possible to provide a light transmission system excellent in reflection returning light resistance while maintaining an optical coupling between the emitting part and the light transmission path with high efficiency. Moreover, the light transmission member realizes an optical transmission device suitable for a high speed and a large capacity optical transmission system with such a high efficiency optical coupling and excellent in a reflection resistant characteristic. |
