Patent ID: 6684011
Filing Date: 2004-01-27
Classification: G02B

Abstract:
A spot size converter for converting the spot size of input optical signal received from an input optical fiber and outputting the converted optical signal, said spot size converter comprising:an input optical waveguide formed on a semiconductor substrate and connected to said input optical fiber to receive input optical signal; an output optical waveguide formed on said input optical waveguide to form a double-layer structure with said input optical waveguide on said semiconductor substrate and to output the optical signal after converting the spot size of the optical signal; and a unidirectional side-tapered optical waveguide formed in the same layer as said output optical waveguide and integrated to one side of said output optical waveguide near to said input optical fiber, and having a shape tapered in one side along a given length in the longitudinal direction of said output optical waveguide, wherein the spot size of the input optical signal transferred from said input optical waveguide to said unidirectional side-tapered optical waveguide is gradually converted while the optical signal travels through the unidirectional side-tapered optical waveguide toward the output optical waveguide due to the change in the effective reflective index.