| 摘要 |
PROBLEM TO BE SOLVED: To provide the wavelength selecting device which can select wavelength irrelevantly to polarized light and generates small noise, and is small- sized and low in cost. SOLUTION: On a waveguide substrate 10, two optical waveguides 23 and 24 are formed along the length. One end of the optical waveguide 23 is an input port 14 on which input light 11 is made incident and the other end is an output port 16 where unselected wavelength light 13 is projected. The input- port-14 side of the waveguide 24 is an output part 15 where selected wavelength light 12 is projected. On the side of the input port 14, a TE/TM mode separation part 17 is provided which separates the input light 11 into signal lines of respective propagation modes. On the side of the output port 16, a TE/TM mode coupling part 21 is provided which couples signal lights of the respective propagation modes. Between the TE/TM mode separation part 17 and TE/TM mode coupling part 21, Bragg reflection parts 19 and 22 are provided which perform wavelength selection for the separated signal lights of the respective propagation modes and mode conversion for reflected light. |
