| 摘要 |
A wavelength-selective optical switch device according to the present invention comprises: a light operation element that has polarization-dependent characteristics which output light input from any one of the light input-output ports toward another light input-output port; a condensing lens system that is disposed between the light input-output ports and the light operation element, and that optically couples the light input-output ports and the light operation element; a light dispersion element that is disposed between the light input-output port and the condensing lens system, and that separates light that has been input in a light dispersion direction; a polarization operation element that is disposed between the condensing lens system and the light dispersion element, and that can output two light beams, which have mutually orthogonal polarization states and which are included in the light that has been input, in directions which mutually form an angle in a plane parallel to an optical switch direction; and a polarization rotation element, disposed between the polarization operation element and the light operation element, whereby the two lights beams having mutually orthogonal polarization states output from the polarization operation element are made to have the same polarization direction. Thus it is possible to provide a wavelength-selective optical switch device which has a small footprint, is inexpensive, and has excellent insertion loss characteristics. |
