| 摘要 |
PURPOSE:To obtain a total reflection type optical waveguide switch reduced in its crosstalk and loss by constituting an impurity area of a material having a composition capable of correcting the lowering of a refractive index based upon the doping of impurities. CONSTITUTION:the impurity area 19 formed on the partial area of an upper clad layer 16 is constituted of the material with the high refractive index composition capable of offsetting the lowering of the refractive index due to the doping of the impurities. Thereby, the equivalent refractive index of an optical waveguide part including the impurity area 19 is a high value as compared with a case having no arrangement of the material. Therefore, a difference from the equivalent refractive index of the optical waveguide part including the upper clad layer 16 in an area to which the impurities are not doped is reduced, so that the reflection of light on the reflection face of the impurity area in a light through state is reduced. Consequently, crosstalk in the light through state can be reduced and the total reflection type optical switch with a low loss can be obtained. |
