Directional coupler type optical demultiplexer having periodic structure
Abstract
Abstract PURPOSE:To obtain an optical demultiplexer having sharp dividing characteristics and cut-off characteristics, by combining the dividing characteristics due to providing of a periodic structure region and the dividing characteristics due to a directional coupler in cascade. CONSTITUTION:An incidence region 11, a periodic region 12, and an exit region 13 are provided on a bulk medium 14 having a uniform refractive index, and two optical waveguides 15 and 16 are formed in the bulk medium 14. Optical waveguides 15 and 16 are close to and in parallel with each other across the incidence region 11 and the periodic region 12 to form an optical directional coupler 17, and the refractive index is changed periodically for the direction of light incidence in the periodic region 12 specially. In an optical demultipler having this constitution, when optical waves having plural center wavelengths are incident from an incidence port 1 of the optical waveguide 15, only the optical wave having a specific center wavelength is emitted from an exit port 2 of the optical waveguide 16.
Inventors
- 👤 Yutaka Sasaki
Bibliographic Details
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