| 摘要 |
PURPOSE:To increase the coefft. of absorption and to increase the nonlinearity per unit volume by increasing the equiv. refractive index of the optical waveguide in a region where a nonlinear optical material is formed. CONSTITUTION:This waveguide device consists of the waveguide 2 which is embedded in a substrate 1 and has an exposed front surface and the nonlinear glass waveguide 3 which is formed in the upper part thereof. The waveguide 2 is so designed that the loss at the wavelength of guided light is extremely small. On the other hand, the nonlinear glass waveguide 3 is large in absorption at the wavelength of the guided light and its refractive index is larger than the refractive indices of the substrate 1 and the waveguide 2. In addition, the length L of the nonlinear glass waveguide 3 is so designed that the loss by absorption in this part is not so much large and that the length sufficient to indicate the nonlinearity by the intensity of the guided light to be used is attained. The equiv. refractive index of the waveguide in the part where the optical nonlinear waveguide 3 and the waveguide 2 in the substrate 1 overlap is increased and the light intensity is concentrated toward the nonlinear waveguide 3 in such a case. |
