| 摘要 |
PURPOSE:To change not only the width but also the thickness of a waveguide layer and the numerical aperture in the lengthwise direction of a three- dimensional optical waveguide by bringing a solution containing a component, which raises the refractive index, into contact with a porous glass when this glass becomes transparent. CONSTITUTION:The porous glass like a split-phase glass subjected to etching treatment is formed, and the solution containing the component which raises the refractive index is brought into contact with the porous glass to allow this component to penetrate the porous glass when this glass becomes transparent. Thereafter, the glass is locally heated by irradiation of laser light or the like to dry or solidify said component, and the undried component is removed from the porous glass by a solvent. The whole of the glass is subjected to heat treatment to make a transparent glass of the porous glass, thereby producing the optical waveguide. At this time, only the part where said component is dried or solidified has a refractive index higher than that of the peripheral part and becomes a light propagating part. Thus, the three-dimensional optical waveguide is obtained where not only the width but also the thickness of the waveguide layer and the numerical aperture are changed on demand. |
