Abstract: An integrated optical pickup device for a magnetooptical recording medium (e.g. a magnetooptical recording disk) and/or an optical recording medium (e.g. an optical recording disk) in which a plurality of focusing grating couplers are formed on an optical waveguide layer manufactured on a substrate. A light reflected from a magnetooptical disk or an optical disk is guided by the focusing grating couplers into the waveguide layer to be separated and to be converged therethtough. The converged lights are detected so as to produce a tracking error signal, a focusing error signal, and an information readout signal. The plural focusing grating couplers are fabricated at an identical location on the waveguide in a superimposed fashion. This increases the utilization efficiency of reflection light per each unitary area of the focusing grating couplers and hence the signals are obtained in a stable state.

Abstract: On a substrate (1), a core layer (2) is formed such that the core layer (2) includes a rib section (2a) fabricated to be integral therewith. The core layer (2) and the rib section (2a) are formed with a liquid material to be solidified under an energy irradiation, for example, a UV-setting resin. A clad layer (3) is disposed on the core layer (2). A buffer layer (4) is formed between the core layer (2) and the substrate (1).

Abstract: On a substrate (1), a core layer (2) is formed such that the core layer (2) includes a rib section (2a) fabricated to be integral therewith. The core layer (2) and the rib section (2a) are formed with a liquid material to be solidified under an energy irradiation, for example, a UV-setting resin. A clad layer (3) is disposed on the core layer (2). A buffer layer (4) is formed between the core layer (2) and the substrate (1).

Abstract: A grating lens is disclosed in which diffraction efficiency varies in the focusing direction of light on a surface of the lens. Also disclosed is a focusing grating coupler in which the diffraction efficiency of a grating formed on an optical waveguide, which is formed on a substrate, varies in the focusing direction of light.