| 摘要 |
PURPOSE:To obtain a titled filter which retains highly stable characteristics even after lapse of a long period of time by laminating rutile films and silica films alternately in optional number of layers on a glass substrate then annealing the films. CONSTITUTION:Rutile (TiO2) films 2 and silica (SiO2) films 3 are laminated on an optical glass substrate 1, which is polished to have a flat surface, by vacuum deposition alternately respectively at suitable thicknesses at about 2Angstrom /sec and 10Angstrom /sec, rates of vapor deposition respectively while the substrate is kept at about 350 deg.C. The substrate is then heated at 100-350 deg.C in air or an oxidative atmosphere to anneal the films. The filter of the multilayered dielectric films which has highly stable characteristics and high reliability, retains the initial characteristics even after lapse of a long period of time and is useful for basic elements such as branching filters for optical communication is obtained. |
