| 摘要 |
PURPOSE:To mass-produce optical waveguides and to facilitate control over the refractive index and thickness of a glass film with a high refractive index by depositing the glass film with the high refractive index on an internal wall and making it into a flat plate in one manufacture process. CONSTITUTION:A glass film 2 with high refractive index is deposited on the internal wall of a quartz glass tube 1. A cut is made in part of this glass tube in a longitudinal direction. The tube 1 with the cut is expanded and drawn while heating (or has the surface pressed by a carbon plate, etc.) into the flat plate, obtaining a glass film 2' with high refractive index on the flat quartz glass 1'. The film 2' confines light, so an optical waveguide with the film 2' as a light propagation path is obtained. When the tube 1 is expanded into the flat plate, the tube is cut into two along a plane containing the tube axis to press semicircular tubes by the carbon plate, etc., into flat plates while heating. |
