| 摘要 |
PURPOSE:To propagate a propagation light beam in the light waveguide line which has been embedded in the substrate, without making it scatter on the surface of the substrate, by forming the maximum part of the refractive index in the internal part of the substrate. CONSTITUTION:On the surface of the substrate 1 is made to adhere a substance 2 consisting of a metal which is diffused in the substrate 1 and increases a refractive index of the substrate 1, or a compound of the metal concerned, and subsequently, is made to adhere a substance 3 consisting of a simple substance containing a metallic ion which is diffused in the substrate 1 and lowers its refractive index. When necessary, a film 4 of a semiconductor or a insulating material is formed between the substance 2 and the substance 3, in order to control the diffusion of the sub stance 3. After that, an area 5 where the refractive index in the substance has increased, and an area 6 where the substance 3 has diffused in the substrate and the refractive index has slightly decreased are formed by applying a DC electric field and simultaneously diffusing a metallic ion in the film 2 and the film 3 to the substrate 1. |
