Design of pitch conversion component for formation of multibeam optical recording head

We describe a design of a planar lightwave circuit for parallel information processing using visible light. The circuit serves as a pitch conversion component (PCC) that can align multiple beams close together and easily composes a compact optical system that can project optical spots at a narrow pitch on a certain small plane. From the viewpoint of its application to optical recording, a PCC is designed to have over 50 waveguides according to the fabrication of waveguides for a blue-violet beam. It is analytically confirmed that a PCC contributes to the formation of a multibeam optical recording head with numerous beams.