| 摘要 |
PURPOSE:To eliminate dependence on the direction of the plane of polarization by providing a stripe-like optical demultiplexing area by forming integrally so that clad areas of one side of a first and a second stripe-like optical waveguides are constituted of core areas of a first and a second stripe-like optical waveguides, respectively, and placing a diffraction grating in the vicinity of this optical waveguide. CONSTITUTION:A stripe-like optical demultiplexing area 5 is provided by forming integrally so that a clad area of one side of a first stripe-like optical waveguide 3 is constituted of a core area of a second strip-like optical waveguide 4, and also, a clad area of one side of a second stripe-like optical waveguide 4 is constituted of a core area of a first stripe-like optical waveguide 3. Also, diffraction gratings 6, 7 having a period given by a function of an equivalent refractive index, respectively are placed in the vicinity of a first and a second stripe-like optical waveguides. In such a way, the dependence on the direction of the plane of polarization is eliminated, and the selected wavelength can be made variable. |
