| 摘要 |
PURPOSE:To attenuate an unnecessary polarized wave and to obtain a splitter of a high quenching ratio by constituting the splitter so that in two emitting ports of a coupler, as for one of them, a slow axis is allowed to coincide with a transmission axis of an optical fiber type polarizer, and the other is allowed to be orthogonal to the transmission axis. CONSTITUTION:When a light beam which is polarized in the long axis direction of an elliptical jacket 12 is made incident on an incident port 4 of a direction coupler 1, since the polarized wave of an output port 6 of transmission side coincides with a transmission axis of a polarizer 2, it passes it through at a low loss, and emitted from an emitting port end 8. On the other hand, a polarized wave of an emitting port 7 of a coupling side coincides with a jacket short axis and goes to orthogonal to the transmission axis, therefore, attenuated and not emitted from an emitting end 9. In the same way, when a light beam which is polarized in the short axis direction of the jacket 12 is made incident on the port 4, it is not emitted from the output end 8 but emitted from the output end 9 without being attenuated. In such a way, an unnecessary polarized wave from the emitting port is attenuated and a polarization beam splitter of a high quenching ratio is obtained. |
