Patent ID: 7327912
Filing Date: 2008-02-05
Classification: G02B

Abstract:
1. A wavelength division multiplexer/demultiplexer comprising: a first sub-waveguide having a width that gradually increases in a progressing direction of an optical signal; and a second sub-waveguide having a width that gradually decreases in the progressing direction of the optical signal passing through the first sub-waveguide, wherein a shape of the second sub-waveguide is defined by the Equation 9, wherein, z 2 denotes a distance from the end of the first sub-waveguide to a position of a progressing optical signal, W 2 is a width of the second sub-waveguide at the position of the progressing optical signal, W i2 is a width of the second sub-waveguide at the contact point of the first and second sub-waveguides, λ g denotes an effective wavelength of the optical signal, and denotes a coupling coefficient of the fundamental and higher modes of the optical signal.