| 摘要 |
PURPOSE:To provide the illuminating device which facilitates taking out of guided light over a relatively long distance and with which linear luminous fluxes are obtainable. CONSTITUTION:This wire-shaped illuminating device D1 is constituted by successively laminating a glass substrate 4, an optical waveguide 3, a thin film 2 and gratings 1 by the following methods: The optical waveguide 3 is first formed by an ion exchange method, etc., on the surface of the rectangular glass substrate 4. A thin film 2 having the refractive index lower than the refractive index of the optical waveguide 3 part is then formed by vapor deposition or sputtering on the surface of the optical waveguide 3. The surface of thin film 2 is then patterned with the gratings 1 by etching or periodic loading of another thin films, etc. The guided light is taken out over a long distance when the thin film 2 is formed thickly to some extent. |
