Optical plane circuit with an optical coupler and a method for manufacturing the same

摘要

An optical plane circuit has a transparent substrate such as a glass plate and a synthetic resin plate, an optical waveguide, and a graded index type lens to serve as an optical coupler which improves the input and/or output efficiency of a light beam in and/or from the optical waveguide. The optical plane circuit does not require troublesome precision registration between the optical waveguide and the optical coupler, and an overall compact circuit may be achieved. Connection loss due to connection between the optical waveguide and the optical coupler is small. The coupling efficiency is not degraded even if the cross- sectional shape of the optical waveguide expands along the plane of the substrate. Input and/or output of a light beam into and/or from the optical waveguide may be performed with excellent efficiency and reliability. A method for manufacturing this optical plane circuit is also provided.