VERTICALLY COUPLED WAVELENGTH VARIABLE OPTICAL FIBER HAVING DOUBLE LATTICE STRUCTURE

摘要

PURPOSE: A vertically coupled wavelength variable optical fiber having double lattice structure is provided to have a double lattice structure where an interval between two lattices is spatially different at a center portion and both ends of a filter. CONSTITUTION: An n-type InP buffer layer is formed an n-type InP substrate(21), and the first waveguide layer(22) is formed on the n-type InP buffer layer. The first waveguide layer(22) is spatially limited so as to have a width of 1-3 micrometers and a length of 3-10nm. An n-type InGaAsP lattice layer(23) is formed on the first waveguide layer(22), and is spatially limited so as to have a double lattice period of 20 to 60 micrometers. A distance between two lattices forming the double lattice is limited spatially. An n-type InP(24) is deposited on the n-type InGaAsP lattice layer, and the second optical waveguide layer(25) of a p-type InGaAsP is deposited on the n-type InP(24). The second optical waveguide layer(25) is spatially limited so as to have a width of 1 to 5 micrometer and a length of 3 to 10mm. A p-type InP clad layer(26) is deposited on the second optical waveguide layer.