| 摘要 |
PURPOSE:To decrease the crosstalk of an optical signal by extending and providing a current injection area on an optical waveguide which is selected when an input light is transmitted through. CONSTITUTION:In accordance with whether a current which is allowed to flow to a current injection area exists or not, a course of a light beam is switched spatially. In a semiconductor optical switch, a current injection area 7A is extended and provided on an optical waveguide which s selected when an input light has transmitted through. In such a way, by utilizing the quality of an InGaAsP waveguide layer which not only generates deterioration of a refractive index by injecting a current but also increases an absorption coefficient of a light beam, the current injection area 7 is expanded onto the waveguide 11 for outputting a transmission light. Therefore, the transmission light at the time of injecting a current is absorbed and attenuated in the waveguide, and a crosstalk at the time of injecting a current, namely, at the time of switching an optical path can be suppressed. |
