Optical waveguide having low optical damage

摘要

An optical waveguide produced from a lithium niobate single crystal substrate diffused thereon titanium is claimed, wherein, as the substrate is used a single crystal of lithium niobate having an optical absorbance coefficient of 0.03 cm-1 or less for a light 420 nm in wavelength. The optical waveguide according to the present invention shows improved resistance against optical damage as compared with prior art waveguides, and is therefore suitable for devices subjected to incidence beam of higher intensity.