PHOTOREGULATION ELEMENT AND PRODUCTION METHOD THEREOF

摘要

The purpose of present inventions is to provide an optical control device having a single-mode waveguide in the optical control device having the ridge waveguide, and to stably manufacture and provide the optical control device having the single-mode waveguide with high precision even when the substrate is a thin plate with the thickness of 10 µm or less. An optical control device having a substrate 1 formed with an optical waveguide, in which the substrate is a thin plate with a thickness of 10 µm or less, at least a portions of the optical waveguide is configured as a ridge waveguide 21, a trench 20 having a width of 10 µm or less is formed on both sidles of at least portions of the ridge waveguide, and a taper waveguide section (area B) continuously changes a light propagation mode of the waveguide between a single-mode and a multi-mode by continuously changing the width or depth of the trench. Additionally, it is desirable that the taper waveguide section is disposed at least in one of a light input sections and a light output section, and light propagating through the waveguide is in the single-mode in a section in which the taper waveguide section is disposed.